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1.
Biochim Biophys Acta Gen Subj ; 1868(11): 130710, 2024 Sep 06.
Artículo en Inglés | MEDLINE | ID: mdl-39245149

RESUMEN

A prokaryotic resistance-based directed evolution system leveraging protein-fragment complementation assay (PCA) was devised, and its proficiency in detecting protein-protein interactions and discriminating varying degrees of binding affinity was demonstrated by two well-characterized protein pairs. Furthermore, we constructed a random mutant library based on the GBPR36K/E45K mutant, characterized by almost no affinity towards EGFP. This library was subjected to PCA-based prokaryotic directed evolution, resulting in the isolation of back-mutated variants. In summary, we have established an expedited, cost-effective, and structural information-independent PCA-based prokaryotic directed evolution platform for nanobody affinity maturation, featuring tunable screening stringency via modulation of antibiotic concentrations.

2.
JAMA Oncol ; 2024 Sep 12.
Artículo en Inglés | MEDLINE | ID: mdl-39264607

RESUMEN

Importance: Disparity in overall survival (OS) and differences in the frequency of driver gene variants by race and ethnicity have been separately observed in patients with colorectal cancer; however, how these differences contribute to survival disparity is unknown. Objective: To quantify the association of molecular, socioeconomic, and clinical covariates with racial and ethnic disparities in overall survival among patients with colorectal cancer. Design, Setting, and Participants: This single-center cohort study was conducted at a tertiary-level cancer center using relevant data on all patients diagnosed with colorectal cancer from January 1, 1973, to March 1, 2023. The relative contribution of variables to the disparity was determined using mediation analysis with sequential multivariate Cox regression models. Main Outcome: OS, from diagnosis date and from start of first-line chemotherapy. Results: The study population of 47 178 patients (median [IQR] age, 57.0 [49-66] years; 20 465 [43.4%] females and 26 713 [56.6%] males; 3.0% Asian, 8.7% Black, 8.8% Hispanic, and 79.4% White individuals) had a median (IQR) follow-up from initial diagnosis of 124 (174) months and OS of 55 (145) months. Compared with White patients, Black patients had worse OS (hazard ratio [HR], 1.16; 95% CI, 1.09-1.24; P <.001), whereas Asian and Hispanic patients had better OS (HR, 0.66; 95% CI, 0.59-0.74; P <.001; and 0.86; 95% CI, 0.81-0.92; P <.001, respectively). When restricted to patients with metastatic disease, the greatest disparity was between Black patients compared with White patients (HR, 1.2; 95% CI, 1.06-1.37; P <.001). Evaluating changes in OS disparity over 20 years showed disparity decreasing among Asian, Hispanic, and White patients, but increasing between Black patients and White patients (HRs, 1.18; 95% CI, 1.07-1.31 for 2008-2012; 1.24, 95% CI, 1.08-1.42 for 2013-2017; and 1.50; 95% CI, 1.20-1.87 for 2018-2023). Survival outcomes for first-line chemotherapy were worse for Black patients compared with White patients (median OS, 18 vs 26 months; HR, 1.30; 95% CI, 1.01-1.70). Among 7628 patients who had clinical molecular testing, APC, KRAS, and PIK3CA showed higher variant frequency in Black patients (false discovery rate [FDR], 0.01; < 0.001; and 0.01, respectively), whereas BRAF and KIT were higher among White patients (FDR, 0.001 and 0.01). Mediation analysis identified neighborhood socioeconomic status as the greatest contributor to OS disparity (29%), followed by molecular characteristics (microsatellite instability status, KRAS variation and BRAF variation, 10%), and tumor sidedness (9%). Conclusions: This single-center cohort study identified substantial OS disparity and differing frequencies of driver gene variations by race and ethnicity. Socioeconomic status had the largest contribution but accounted for less than one-third of the disparity, with substantial contribution from tumor molecular features. Further study of the associations of genetic ancestry and the molecular pathogenesis of colorectal cancer with chemotherapy response is needed.

3.
medRxiv ; 2024 Sep 04.
Artículo en Inglés | MEDLINE | ID: mdl-39281768

RESUMEN

We performed large-scale genome-wide gene-sleep interaction analyses of lipid levels to identify novel genetic variants underpinning the biomolecular pathways of sleep-associated lipid disturbances and to suggest possible druggable targets. We collected data from 55 cohorts with a combined sample size of 732,564 participants (87% European ancestry) with data on lipid traits (high-density lipoprotein [HDL-c] and low-density lipoprotein [LDL-c] cholesterol and triglycerides [TG]). Short (STST) and long (LTST) total sleep time were defined by the extreme 20% of the age- and sex-standardized values within each cohort. Based on cohort-level summary statistics data, we performed meta-analyses for the one-degree of freedom tests of interaction and two-degree of freedom joint tests of the main and interaction effect. In the cross-population meta-analyses, the one-degree of freedom variant-sleep interaction test identified 10 loci (P int <5.0e-9) not previously observed for lipids. Of interest, the ASPH locus (TG, LTST) is a target for aspartic and succinic acid metabolism previously shown to improve sleep and cardiovascular risk. The two-degree of freedom analyses identified an additional 7 loci that showed evidence for variant-sleep interaction (P joint <5.0e-9 in combination with P int <6.6e-6). Of these, the SLC8A1 locus (TG, STST) has been considered a potential treatment target for reduction of ischemic damage after acute myocardial infarction. Collectively, the 17 (9 with STST; 8 with LTST) loci identified in this large-scale initiative provides evidence into the biomolecular mechanisms underpinning sleep-duration-associated changes in lipid levels. The identified druggable targets may contribute to the development of novel therapies for dyslipidemia in people with sleep disturbances.

4.
Artículo en Inglés | MEDLINE | ID: mdl-39259318

RESUMEN

BACKGROUND: Oncocytic thyroid carcinoma (OTC) is a rare subtype of thyroid cancer known for its distinctive morphology and high likelihood of recurrence, setting it apart from follicular thyroid carcinoma (FTC). Despite this, there is limited research comparing the clinicopathological characteristics and outcomes of OTC and FTC. METHODS: We retrospectively searched through the Surveillance, Epidemiology, and End-Results (SEER) database (2004-2015) for histologically diagnosed OTC and FTC patients. Kaplan-Meier analysis, propensity score matching (PSM), univariate Cox proportional risk regression model, and subgroup analysis were employed to investigate the prognostic effect of clinicopathological features and treatment regimens on survival outcomes of OTC and FTC patients. RESULTS: 2329 OTC patients and 5679 FTC patients were included in the study. OTC patients were prone to older age, white race, lymph node metastasis, distal metastasis, extension and multiple primary tumors compared with FTC patients. After using a 1:1 PSM matching ratio, there were no significant differences in demographic and clinicopathological characteristics between the matched groups. Further Cox regression analysis showed that OTC patients had lower overall survival (OS) and cancer-specific survival (CSS) in contrast with FTC patients. Subgroup survival analysis suggested that the OTC patients were related to lower OS in subgroups including those over 55 years old, male sex, white ethnicity, extrathyroidal extension, single primary tumor, surgery and without chemotherapy compared with the FTC patients in these subgroups. In addition, the OTC patients were connected with lower CSS in subgroups including male sex, white ethnicity, married status, tumor size is less than 20 mm or more than 40 mm, N0 stage, localized stage, single primary tumor, surgery, radiotherapy, and without chemotherapy compared with the FTC patients in these subgroups. Meanwhile, the OTC patients had lower CSS compared to FTC patients regardless of age and extrathyroidal extension. CONCLUSIONS: The results suggested that OTC patients have unique clinical features and poorer prognoses compared to FTC patients. Surgical resection and radioactive iodine therapy are recommended for OTC patients and FTC patients. It is worth noting that the prognosis of OTC relies largely on the selection of treatment strategies. Therefore, our results highlighted the clinical significance of the early distinguishment and the correct choice of treatment in OTC patients.

5.
Artículo en Inglés | MEDLINE | ID: mdl-39087944

RESUMEN

BACKGROUND: Thyroid differentiation score (TDS), calculated based on mRNA expression levels of 16 genes controlling thyroid metabolism and function, has been proposed as a measure to quantify differentiation in PTC. The objective of this study is to determine whether TDS is associated with survival outcomes across patient cohorts. METHODS: Two independent cohorts of PTC patients were used: 1) the Cancer Genome Atlas (TCGA) thyroid cancer study (N=372), 2) MD Anderson Cancer Center (MDACC) cohort (N=111). The primary survival outcome of interest was progression-free interval (PFI). Association with overall survival (OS) was also explored. The Kaplan-Meier method and Cox proportional hazards models were used for survival analyses. RESULTS: In both cohorts, TDS was associated with tumor and nodal stage at diagnosis as well as tumor driver mutation status. High TDS was associated with longer PFI on univariable analyses across cohorts. After adjusting for overall stage, TDS remained significantly associated with PFI in the MDACC cohort only (aHR 0.67, 95%CI 0.52-0.85). In subgroup analyses stratified by tumor driver mutation status, higher TDS was most consistently associated with longer PFI in BRAFV600E-mutated tumors across cohorts after adjusting for overall stage (TCGA: aHR 0.60, 95% CI: 0.33-1.07; MDACC: aHR 0.59, 95% CI: 0.42-0.82). For OS, increasing TDS was associated with longer OS in the overall MDACC cohort (aHR=0.78, 95% CI:0.63-0.96), where the median duration of follow-up was 12.9 years. CONCLUSION: TDS quantifies the spectrum of differentiation status in PTC and may serve as a potential prognostic biomarker in PTC, mostly promisingly in BRAFV600E-mutated tumors.

6.
Discov Oncol ; 15(1): 359, 2024 Aug 19.
Artículo en Inglés | MEDLINE | ID: mdl-39160379

RESUMEN

OBJECTIVE: Bibliometrics was employed in this study to determine the research trends in the worldwide application of 3D printing technology to treat bone tumors over the previous 10 years. METHODS: Published from 2013 to 2022, the papers related to bone tumors treated with 3D printing were located in Web of Science Core Collection (WoSCC), PubMed, and Scopus. The screened articles were included in this bibliometric study. From these papers in WoSCC, information on annual publications, journals, keywords, countries, authors, institutions, and cited references were extracted and visualized with CiteSpace (version 6.1.R6) software to investigate the state of bone tumor treatment using 3D printing as well as research hotspots. The Carrot2 online visualization tool and Vosviewer software (version 1.6.20) were employed to visualize the publications from PubMed and Scopus, respectively, in order to ascertain the most popular research topics from both databases. RESULTS: A total of 606, 233, and 364 publications were obtained from WoSCC, PubMed, and Scopus, respectively, between the years 2013 and 2022. In WoSCC, the peak number of publications was found in 2021, with 145 publications published. Acta Biomaterialia (11 publications) and World Neurosurgery (10 publications) were the most prolific journals, and Biomaterials was the journal cited the most (244 times). Yong Zhou was the most productive author with 14 publications, while Kwok-Chuen Wong (69 citations) and William F Enneking, (69 citations) possessed the most citations. The country with the largest quantity of publications was China (207). Among all institutions, Shanghai Jiao Tong University produced the most publications (29). Rapid prototyping was the keyword with the strongest citation burst (4.73). 'Reconstruction', 'surgery', 'resection', and 'design' caught the significant attention of researchers. 3D-printed materials, pelvic reconstruction, mandibular reconstruction, computer-assisted surgical techniques, photothermal therapy, and in vitro experiments were recognized as hot subjects and trends in current research. The most frequently occurring topics in Scopus are not significantly different from those found in WoSCC. The most prevalent research areas in PubMed encompass implant, patient-specific, bioceramic, models, and pelvic.

7.
Sensors (Basel) ; 24(13)2024 Jun 30.
Artículo en Inglés | MEDLINE | ID: mdl-39001036

RESUMEN

Gear fault detection and remaining useful life estimation are important tasks for monitoring the health of rotating machinery. In this study, a new benchmark for endurance gear vibration signals is presented and made publicly available. The new dataset was used in the HUMS 2023 conference data challenge to test anomaly detection algorithms. A survey of the suggested techniques is provided, demonstrating that traditional signal processing techniques interestingly outperform deep learning algorithms in this case. Of the 11 participating groups, only those that used traditional approaches achieved good results on most of the channels. Additionally, we introduce a signal processing anomaly detection algorithm and meticulously compare it to a standard deep learning anomaly detection algorithm using data from the HUMS 2023 challenge and simulated signals. The signal processing algorithm surpasses the deep learning algorithm on all tested channels and also on simulated data where there is an abundance of training data. Finally, we present a new digital twin that enables the estimation of the remaining useful life of the tested gear from the HUMS 2023 challenge.


Asunto(s)
Algoritmos , Procesamiento de Señales Asistido por Computador , Humanos , Vibración , Aprendizaje Profundo
8.
bioRxiv ; 2024 Jul 05.
Artículo en Inglés | MEDLINE | ID: mdl-39005348

RESUMEN

Intra-tumor heterogeneity is an important driver of tumor evolution and therapy response. Advances in precision cancer treatment will require understanding of mutation clonality and subclonal architecture. Currently the slow computational speed of subclonal reconstruction hinders large cohort studies. To overcome this bottleneck, we developed Clonal structure identification through Pairwise Penalization, or CliPP, which clusters subclonal mutations using a regularized likelihood model. CliPP reliably processed whole-genome and whole-exome sequencing data from over 12,000 tumor samples within 24 hours, thus enabling large-scale downstream association analyses between subclonal structures and clinical outcomes. Through a pan-cancer investigation of 7,827 tumors from 32 cancer types, we found that high subclonal mutational load (sML), a measure of latency time in tumor evolution, was significantly associated with better patient outcomes in 16 cancer types with low to moderate tumor mutation burden (TMB). In a cohort of prostate cancer patients participating in an immunotherapy clinical trial, high sML was indicative of favorable response to immune checkpoint blockade. This comprehensive study using CliPP underscores sML as a key feature of cancer. sML may be essential for linking mutation dynamics with immunotherapy response in the large population of non-high TMB cancers.

9.
medRxiv ; 2024 Jul 10.
Artículo en Inglés | MEDLINE | ID: mdl-39040185

RESUMEN

Purpose: Current clinical guidelines for genetic testing for Li-Fraumeni Syndrome (LFS) have many limitations, primarily the criteria don't consider detailed personal and family history information and may miss many individuals with LFS. A personalized risk assessment tool, LFSPRO, was created to estimate a proband's risk for LFS based on personal and family history information. The purpose of this study is to compare LFSPRO to existing clinical criteria to determine if LFSPRO can outperform these tools. Additionally, we gauged genetic counselors' (GCs) experience using LFSPRO for their patients. Methods: Between December 2021 and March 2024, GCs identified patients concerning for LFS based on the patients' personal and family history information. This information was entered into LFSPRO to predict the risk to have a pathogenic/pathogenic (LP/P) germline TP53 variant. Sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) was compared between LFSPRO and Chompret criteria. Select GCs were asked to fill out surveys regarding their experience using LFSPRO following their genetic counseling appointments. Results: LFSPRO's sensitivity and specificity were 0.529 and 0.781 compared to Chompret's respective 0.235 and 0.677. Additionally, LFSPRO had a positive predictive value (PPV) of 0.30 compared to Chompret's 0.114. LFSPRO's risk prediction was concordant with genetic testing results in 75% of probands. Eighty-one percent of GC surveys reported LFSPRO being concordant with the GC's expectations and 75% would feel comfortable sharing the results with patients. Conclusion: LFSPRO showed improved sensitivity and specificity compared to Chompret criteria and GCs report a positive experience with LFSPRO. LFSPRO can be used to increase access to genetic testing for patients at risk for LFS and could help healthcare providers give more direct risk assessments regarding LFS testing and management for patients.

10.
Res Sq ; 2024 Jul 17.
Artículo en Inglés | MEDLINE | ID: mdl-39070651

RESUMEN

Although both short and long sleep duration are associated with elevated hypertension risk, our understanding of their interplay with biological pathways governing blood pressure remains limited. To address this, we carried out genome-wide cross-population gene-by-short-sleep and long-sleep duration interaction analyses for three blood pressure traits (systolic, diastolic, and pulse pressure) in 811,405 individuals from diverse population groups. We discover 22 novel gene-sleep duration interaction loci for blood pressure, mapped to 23 genes. Investigating these genes' functional implications shed light on neurological, thyroidal, bone metabolism, and hematopoietic pathways that necessitate future investigation for blood pressure management that caters to sleep health lifestyle. Non-overlap between short sleep (12) and long sleep (10) interactions underscores the plausible nature of distinct influences of both sleep duration extremes in cardiovascular health. Several of our loci are specific towards a particular population background or sex, emphasizing the importance of addressing heterogeneity entangled in gene-environment interactions, when considering precision medicine design approaches for blood pressure management.

11.
New Phytol ; 243(6): 2214-2234, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39039772

RESUMEN

Ultraviolet (UV) radiation influences development and genome stability in organisms; however, its impact on meiosis, a special cell division essential for the delivery of genetic information across generations in eukaryotes, has not yet been elucidated. In this study, by performing cytogenetic studies, we reported that UV radiation does not damage meiotic chromosome integrity but attenuates centromere-mediated chromosome stability and induces unreduced gametes in Arabidopsis thaliana. We showed that functional centromere-specific histone 3 (CENH3) is required for obligate crossover formation and plays a role in the protection of sister chromatid cohesion under UV stress. Moreover, we found that UV specifically alters the orientation and organization of spindles and phragmoplasts at meiosis II, resulting in meiotic restitution and unreduced gametes. We determined that UV-induced meiotic restitution does not rely on the UV Resistance Locus8-mediated UV perception and the Tapetal Development and Function1- and Aborted Microspores-dependent tapetum development, but possibly occurs via altered JASON function and downregulated Parallel Spindle1. This study provides evidence that UV radiation influences meiotic genome stability and gametophytic ploidy consistency in flowering plants.


Asunto(s)
Arabidopsis , Centrómero , Inestabilidad Genómica , Meiosis , Ploidias , Rayos Ultravioleta , Meiosis/efectos de la radiación , Meiosis/genética , Centrómero/genética , Centrómero/efectos de la radiación , Inestabilidad Genómica/efectos de la radiación , Arabidopsis/genética , Arabidopsis/efectos de la radiación , Arabidopsis/crecimiento & desarrollo , Arabidopsis/fisiología , Células Germinativas de las Plantas/efectos de la radiación , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Histonas/metabolismo , Huso Acromático/efectos de la radiación
12.
Carbohydr Polym ; 339: 122262, 2024 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-38823926

RESUMEN

Chitosan has been widely used in biomedical fields due to its good antibacterial properties, excellent biocompatibility, and biodegradability. In this study, a pH-responsive and self-healing hydrogel was synthesized from 3-carboxyphenylboronic acid grafted with chitosan (CS-BA) and polyvinyl alcohol (PVA). The dynamic boronic ester bonds and intermolecular hydrogen bonds are responsible for the hydrogel formation. By changing the mass ratio of CS-BA and PVA, the tensile stress and compressive stress of hydrogel can controlled in the range of 0.61 kPa - 0.74 kPa and 295.28 kPa - 1108.1 kPa, respectively. After doping with tannic acid (TA)/iron nanocomplex (TAFe), the hydrogel successful killed tumor cells through the near infrared laser-induced photothermal conversion and the TAFe-triggered reactive oxygen species generation. Moreover, the photothermal conversion of the hydrogel and the antibacterial effect of CS and TA give the hydrogel a good antibacterial effect. The CS-BA/PVA/TAFe hydrogel exhibit good in vivo and in vitro anti-tumor recurrence and antibacterial ability, and therefore has the potential to be used as a powerful tool for the prevention of local tumor recurrence and bacterial infection after surgery.


Asunto(s)
Antibacterianos , Quitosano , Hidrogeles , Recurrencia Local de Neoplasia , Alcohol Polivinílico , Taninos , Quitosano/química , Quitosano/farmacología , Hidrogeles/química , Hidrogeles/farmacología , Concentración de Iones de Hidrógeno , Animales , Antibacterianos/farmacología , Antibacterianos/química , Alcohol Polivinílico/química , Ratones , Recurrencia Local de Neoplasia/prevención & control , Taninos/química , Taninos/farmacología , Humanos , Staphylococcus aureus/efectos de los fármacos , Ácidos Borónicos/química , Escherichia coli/efectos de los fármacos , Línea Celular Tumoral , Especies Reactivas de Oxígeno/metabolismo , Hierro/química , Infección de la Herida Quirúrgica/prevención & control
13.
ACS Omega ; 9(23): 24948-24958, 2024 Jun 11.
Artículo en Inglés | MEDLINE | ID: mdl-38882107

RESUMEN

Measuring the physicochemical properties of molecules is an iterative but integral process in the drug development process. A strategy to overcome the challenges in maximizing assay throughput relies on the usage of in silico machine learning (ML) prediction models trained on experimental data. Consequently, the performance of these in silico models are dependent on the quality of the utilized experimental data. To improve the data quality, we have designed and implemented an automated robotic system to prepare and run physicochemical property assays (Automated Robotic Interface for Assays, ARIA) with an increase in sample throughput of 6 to10-fold. Through this process, we overcame major challenges and achieved consistent reproducible assay data compared to semiautomated assay preparation.

15.
Light Sci Appl ; 13(1): 125, 2024 May 29.
Artículo en Inglés | MEDLINE | ID: mdl-38806501

RESUMEN

Structured illumination microscopy (SIM) has emerged as a promising super-resolution fluorescence imaging technique, offering diverse configurations and computational strategies to mitigate phototoxicity during real-time imaging of biological specimens. Traditional efforts to enhance system frame rates have concentrated on processing algorithms, like rolling reconstruction or reduced frame reconstruction, or on investments in costly sCMOS cameras with accelerated row readout rates. In this article, we introduce an approach to elevate SIM frame rates and region of interest (ROI) coverage at the hardware level, without necessitating an upsurge in camera expenses or intricate algorithms. Here, parallel acquisition-readout SIM (PAR-SIM) achieves the highest imaging speed for fluorescence imaging at currently available detector sensitivity. By using the full frame-width of the detector through synchronizing the pattern generation and image exposure-readout process, we have achieved a fundamentally stupendous information spatial-temporal flux of 132.9 MPixels · s-1, 9.6-fold that of the latest techniques, with the lowest SNR of -2.11 dB and 100 nm resolution. PAR-SIM demonstrates its proficiency in successfully reconstructing diverse cellular organelles in dual excitations, even under conditions of low signal due to ultra-short exposure times. Notably, mitochondrial dynamic tubulation and ongoing membrane fusion processes have been captured in live COS-7 cell, recorded with PAR-SIM at an impressive 408 Hz. We posit that this novel parallel exposure-readout mode not only augments SIM pattern modulation for superior frame rates but also holds the potential to benefit other complex imaging systems with a strategic controlling approach.

16.
Front Pharmacol ; 15: 1345070, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38799165

RESUMEN

Background: Vandetanib is a small-molecule tyrosine kinase inhibitor. It exerts its therapeutic effects primarily in a range of lung cancers by inhibiting the vascular endothelial growth factor receptor 2. However, it remains unclear whether vandetanib has therapeutic benefits in other lung diseases, particularly asthma. The present study investigated the pioneering use of vandetanib in the treatment of asthma. Methods: In vivo experiments including establishment of an asthma model, measurement of airway resistance measurement and histological analysis were used primarily to confirm the anticontractile and anti-inflammatory effects of vandetanib, while in vitro experiments, including measurement of muscle tension and whole-cell patch-clamp recording, were used to explore the underlying molecular mechanism. Results: In vivo experiments in an asthmatic mouse model showed that vandetanib could significantly alleviate systemic inflammation and a range of airway pathological changes including hypersensitivity, hypersecretion and remodeling. Subsequent in vitro experiments showed that vandetanib was able to relax the precontracted rings of the mouse trachea via calcium mobilization which was regulated by specific ion channels including VDLCC, NSCC, NCX and K+ channels. Conclusions: Taken together, our study demonstrated that vandetanib has both anticontractile and anti-inflammatory properties in the treatment of asthma, which also suggests the feasibility of using vandetanib in the treatment of asthma by reducing abnormal airway contraction and systemic inflammation.

17.
Angew Chem Int Ed Engl ; 63(32): e202403023, 2024 Aug 05.
Artículo en Inglés | MEDLINE | ID: mdl-38763905

RESUMEN

The efficient electrosynthesis of hydrogen peroxide (H2O2) via two-electron oxygen reduction reaction (2e- ORR) in neutral media is undoubtedly a practical route, but the limited comprehension of electrocatalysts has hindered the system advancement. Herein, we present the design of model catalysts comprising mesoporous carbon spheres-supported Pd nanoparticles for H2O2 electrosynthesis at near-zero overpotential with approximately 95 % selectivity in a neutral electrolyte. Impressively, the optimized Pd/MCS-8 electrocatalyst in a flow cell device achieves an exceptional H2O2 yield of 15.77 mol gcatalyst -1 h-1, generating a neutral H2O2 solution with an accumulated concentration of 6.43 wt %, a level sufficiently high for medical disinfection. Finite element simulation and experimental results suggest that mesoporous carbon carriers promote O2 enrichment and localized pH elevation, establishing a favorable microenvironment for 2e- ORR in neutral media. Density functional theory calculations reveal that the robust interaction between Pd nanoparticles and the carbon carriers optimized the adsorption of OOH* at the carbon edge, ensuring high active 2e- process. These findings offer new insights into carbon-loaded electrocatalysts for efficient 2e- ORR in neutral media, emphasizing the role of carrier engineering in constructing favorable microenvironments and synergizing active sites.

18.
Anal Biochem ; 691: 115556, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38705226

RESUMEN

we developed an effective protein precipitation method for determination of levamlodipine in human plasma using LC-MS/MS. Sample extraction was carried out by using liquid-liquid extraction in 96-well plate format. (S)-Amlodipine-d4 was used as internal standard (IS). The chromatographic separation was achieved using Philomen Chiral MX (2) column (3 µm, 2.1 × 100 mm). Mobile phase A was comprised of Acetonitrile (ACN), Mono ethanol amine (MEA) and Iso-Propyl alcohol (IPA) (1000:1:10, v/v/v), Mobile phase B was IPA-ACN (2:1, v/v). The flow rate was 0.4 mL/min. The total run time of each sample was 4.0 min with gradient elution. LC-MS/MS spectra were generated in positive ion mode, and multiple reaction monitoring (MRM) was used to detect the following transitions: m/z 409.20 â†’ 238.15 for levamlodipine and 415.25 â†’ 240.20 for (S)-Amlodipine-d4 (the IS). The method was linear from 50 to 10000 pg/mL(R2=0.9988489),and the lower limit of quantification (LLOQ) was 50 pg/mL. This method was applied to a bioequivalence study of levamlodipine.


Asunto(s)
Niacina , Humanos , Amlodipino/sangre , Amlodipino/farmacocinética , Dihidropiridinas/sangre , Dihidropiridinas/farmacocinética , Dihidropiridinas/química , Límite de Detección , Cromatografía Líquida con Espectrometría de Masas , Extracción Líquido-Líquido , Niacina/análogos & derivados , Niacina/sangre , Espectrometría de Masas en Tándem/métodos
19.
Neurol Res ; 46(6): 525-537, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38563325

RESUMEN

BACKGROUND: Vascular dementia (VD) is the second most common type of dementia worldwide. Previous studies have proven that transcranial direct current stimulation (tDCS) has potential applications in relieving cognitive impairment in VD animal models. The purpose of this study was to probe the mechanism by which tDCS combined with swimming exercise improves the learning and memory abilities of VD model rats. METHOD: The VD rat model was induced using the permanent bilateral common carotid artery occlusion (2-VO) method; tDCS was applied to the rats and then they took part in swimming exercises. Rat memory, platform crossing time, and platform crossing frequency were analyzed via a water maze experiment. Nerve damage in the cortex and hippocampal CA1 area of the rats was observed using Nissl staining. Western blotting, immunohistochemistry, immunofluorescence staining and reverse transcription quantitative polymerase chain reaction (RT - qPCR) were used to determine the expression of related proteins and genes. The levels of oxidative stress were detected by kits. RESULTS: We demonstrated that VD model rats treated with tDCS combined with swimming exercise exhibited significant improvement in memory, and VD model rats exhibited significantly reduced neuronal loss in the hippocampus, and reduced microglial activation and M1 polarization. tDCS combined with swimming exercise protects VD model rats from oxidative stress through the miR-223-3p/protein arginine methyltransferase 8 (PRMT8) axis and inhibits the activation of the TLR4/NF-κB signaling pathway. CONCLUSION: Our results suggest that tDCS combined with swimming exercise improved the learning and memory ability of VD model rats by regulating the expression of PRMT8 through miR-223-3p to affect microglial activation and M1 polarization.


Asunto(s)
Demencia Vascular , Memoria , MicroARNs , Microglía , Natación , Estimulación Transcraneal de Corriente Directa , Animales , MicroARNs/metabolismo , MicroARNs/genética , Masculino , Microglía/metabolismo , Demencia Vascular/terapia , Ratas , Estimulación Transcraneal de Corriente Directa/métodos , Memoria/fisiología , Ratas Sprague-Dawley , Condicionamiento Físico Animal/fisiología , Condicionamiento Físico Animal/métodos , Modelos Animales de Enfermedad , Aprendizaje por Laberinto/fisiología
20.
Aging (Albany NY) ; 16(8): 7188-7216, 2024 04 19.
Artículo en Inglés | MEDLINE | ID: mdl-38643462

RESUMEN

BACKGROUND: This study aims to identify the essential cell cycle-related genes associated with prognosis in breast cancer (BRCA), and to verify the relationship between the central gene and immune infiltration, so as to provide detailed and comprehensive information for the treatment of BRCA. MATERIALS AND METHODS: Gene expression profiles (GSE10780, GSE21422, GSE61304) and the Cancer Genome Atlas (TCGA) BRCA data were used to identify differentially expressed genes (DEGs) and further functional enrichment analysis. STRING and Cytoscape were employed for the protein-protein interaction (PPI) network construction. TPX2 was viewed as the crucial prognostic gene by the Survival and Cox analysis. Furthermore, the connection between TPX2 expression and immune infiltrating cells and immune checkpoints in BRCA was also performed by the TIMER online database and R software. RESULTS: A total of 18 cell cycle-related DEGs were identified in this study. Subsequently, an intersection analysis based on TCGA-BRCA prognostic genes and the above DEGs identified three genes (TPX2, UBE2C, CCNE2) as crucial prognostic candidate biomarkers. Moreover, we also demonstrated that TPX2 is closely associated with immune infiltration in BRCA and a positive relation between TPX2 and PD-L1 expression was firstly detected. CONCLUSIONS: These results revealed that TPX2 is a potential prognostic biomarker and closely correlated with immune infiltration in BRCA, which could provide powerful and efficient strategies for breast cancer immunotherapy.


Asunto(s)
Biomarcadores de Tumor , Neoplasias de la Mama , Proteínas de Ciclo Celular , Regulación Neoplásica de la Expresión Génica , Proteínas Asociadas a Microtúbulos , Humanos , Neoplasias de la Mama/genética , Neoplasias de la Mama/inmunología , Neoplasias de la Mama/mortalidad , Femenino , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Biomarcadores de Tumor/genética , Pronóstico , Proteínas Asociadas a Microtúbulos/genética , Mapas de Interacción de Proteínas/genética , Perfilación de la Expresión Génica , Ciclo Celular/genética , Bases de Datos Genéticas
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