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1.
Neural Regen Res ; 18(1): 226-232, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35799547

RESUMO

Previous studies have shown that berberine has neuroprotective effects against Alzheimer's disease, including antagonizing tau phosphorylation, and inhibiting acetylcholinesterase activity and neural cell apoptosis. However, its low bioavailability and adverse reactions with conventional administration limit its clinical application. In this study, we prepared berberine nanoliposomes using liposomes characterized by low toxicity, high entrapment efficiency, and biodegradability, and modified them with lactoferrin. Lactoferrin-modified berberine nanoliposomes had uniform particle size and high entrapment efficiency. We used the lactoferrin-modified berberine nanoliposomes to treat a mouse model of Alzheimer's disease established by injection of amyloid-beta 1-42 into the lateral ventricle. Lactoferrin-modified berberine nanoliposomes inhibited acetylcholinesterase activity and apoptosis in the hippocampus, reduced tau over-phosphorylation in the cerebral cortex, and improved mouse behavior. These findings suggest that modification with lactoferrin can enhance the neuroprotective effects of berberine nanoliposomes in Alzheimer's disease.

2.
Bioact Mater ; 20: 259-270, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35702611

RESUMO

Rationale: Hypoxia in tumor microenvironment (TME) represents an obstacle to the efficacy of immunotherapy for pancreatic ductal adenocarcinoma (PDAC) through several aspects such as increasing the expression of immune checkpoints or promoting fibrosis. Reversing hypoxic TME is a potential strategy to improve the validity of immune checkpoint blockade (ICB). Methods: Here, we synthesized polydopamine-nanoparticle-stabilized oxygen microcapsules with excellent stabilization, bioavailability, and biocompatibility for direct oxygen delivery into tumor sites by interfacial polymerization. Results: We observed oxygen microcapsules enhanced the oxygen concentration in the hypoxia environment and maintained the oxygen concentration for a long period both in vitro and in vivo. We found that oxygen microcapsules could significantly improve the efficiency of ICB against PDAC in vivo. Mechanismly, combined treatments using oxygen microcapsules and ICB could reduce the infiltration of tumor-associated macrophages (TAMs) and polarized pro-tumor M2 macrophages into anti-tumor M1 macrophages. In addition, combined treatments could elevate the proportion of T helper subtype 1 cells (Th1 cells) and cytotoxic T lymphocytes cells (CTLs) to mediate anti-tumor immune response in TME. Conclusion: In summary, this pre-clinical study indicated that reversing hypoxia in TME by using oxygen microcapsules was an effective strategy to improve the performances of ICB on PDAC, which holds great potential for treating PDAC in the future.

5.
Adv Mater ; : e2205217, 2022 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-35921550

RESUMO

Metal halide perovskites combine excellent electronic and optical properties such as defect tolerance and high photoluminescence efficiency with the benefits of low-cost, large area, solution-based processing. Composition- and dimension-tunable properties of perovskites have already been utilized in bright and efficient light-emitting diodes (LEDs). At the same time, there are still great challenges ahead to achieve operational and spectral stability of these devices. In this review, we consider the origins of instability of perovskite materials, and reasons for their degradation in LEDs. We then review the strategies on improving the stability of perovskite materials such as compositional engineering, dimensionality control, defect passivation, suitable encapsulation matrices, and fabrication of core/shell perovskite nanocrystals. For improvement of the operational stability of perovskite LEDs, we consider use of inorganic charge transport layers, optimization of charge balance, and proper thermal management. We conclude this review with a detailed account of the current challenges and a perspective on the key approaches and opportunities on how to reach the goal of stable, bright and efficient perovskite LEDs. This article is protected by copyright. All rights reserved.

6.
J Clin Sleep Med ; 2022 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-35912683

RESUMO

STUDY OBJECTIVES: To investigate the association of 24-hour urinary potassium excretion with subjective sleep quality in the general population. METHODS: In this cross-sectional study, a population of patients aged 18 years or older was randomly selected from Xinjiang, China in 2019, 24-hour urine samples collected, and Pittsburgh Sleep Quality Index (PSQI) questionnaires assessed. Participants were divided into two groups (upper and lower median of 24-hour urinary potassium excretion [24.8 µmol/L]). Poor sleep quality was defined as PSQI global score ≥ 6. Associations between 24-hour urinary potassium excretion and sleep quality were assessed by multiple logistic regression analysis in total participants and those stratified by sex. RESULTS: In total, 24-hour urine samples were collected from 1,147 participants, of whom data for those with complete urine samples and PSQI data were analyzed (N = 727; mean age = 48.7 years; percentage of women = 62%). Compared with the upper median group for 24-hour urinary potassium excretion, the lower median group showed a significantly higher PSQI global score (6 vs 5, P=0.011), and prevalence of poor sleep quality (51.7% vs 42.2%, P=0.011). In a fully-adjusted model of multivariate logistic regression, the lower median group showed 1.50-fold increased odds for presence of poor sleep quality (95% confidence interval:1.01-2.24, P=0.045). Sex-specific analyses translated these results to women, but not to men. CONCLUSIONS: These results suggest that low potassium intake, indicated by lower potassium excretion, is associated with poor sleep quality in the general population, especially among women. Therefore, additional research is necessary to clarify the effect of increasing potassium intake to improve sleep quality.

7.
Diagn Cytopathol ; 2022 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-35912779

RESUMO

BACKGROUND: To investigate the clinical value of the ThinPrep cytologic test (TCT) with the E6/E7 mRNA test for cervical cancer screening in disease diagnosis. METHODS: A total of 405 samples from Dazhou Central Hospital from April 2017 to July 2020 were collected, and we conducted a comparative analysis of the diagnostic performance of several test methods both individually andcombination. RESULTS: The sensitivity, specificity, positive predictive value, negative predictive value, accuracy, and area under the curve (AUC) were compared by single TCT, E6/E7 mRNA test, and combination methods. The TCT+E6/E7mRNA test was confirmed to have a relatively higher specificity of 80.32% (95% CI: 75.40%-84.48%, both P < 0.001), and AUC value (0.78, 95% CI: 0.73-0.83, and P < 0.001). CONCLUSION: The relative diagnostic value may be further improved by the combined detection of TCT and E6/E7 mRNA test. The combined detection of TCT and the E6/E7 mRNA test is expected to become a potential indicator for cervical lesions.

8.
Mikrochim Acta ; 189(9): 323, 2022 08 06.
Artigo em Inglês | MEDLINE | ID: mdl-35933502

RESUMO

A new strategy is proposed for ultrasensitive detection of chlorogenic acid (CGA) by fabricating an electrochemiluminescence resonance energy transfer (ECL-RET) sensing platform. The novel system designed by introducing ruthenium-based 2D metal-organic framework nanosheets (Ru@Zn-MOF) as ECL acceptor and L-cysteine capped CdS quantum dots (L-CdS QDs) as ECL donor, exhibited good ECL response. The possible mechanism of the modified electrode surface reaction was discussed. Modifying of the electrode surface by application of L-CdS QDs directly on ultrathin MOF nanosheets greatly shortened the electron-transfer distance and reduce energy loss, therefore significantly improving the ECL efficiency. The prepared sensor demonstrated good stability and highly selective detection of the target molecule. Under optimal conditions, the constructed sensor for the detection of CGA exhibited a wide linear range from 1.0 × 10-10 to 1.0 × 10-4 mol·L-1 and a low detection limit of 3.2 × 10-11 mol·L-1 with a correction coefficient of 0.995. The recovery for spiked samples was calculated to be 94.4-109% and the RSD was 1.07-1.72% in real samples. The obtained sensor is considered to be a promising platform for CGA detection. Electrochemiluminescence resonance energy transfer (ECL-RET) sensing platform is used for the detection for chlorogenic acid.


Assuntos
Técnicas Biossensoriais , Pontos Quânticos , Rutênio , Ácido Clorogênico , Técnicas Eletroquímicas , Transferência de Energia , Medições Luminescentes
9.
Research (Wash D C) ; 2022: 9767651, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35935140

RESUMO

Most van der Waals two-dimensional (2D) materials without surface dangling bonds show limited surface activities except for their edge sites. Ultrathin Bi2Se3, a topological insulator that behaves metal-like under ambient conditions, has been overlooked on its surface activities. Herein, through a topochemical conversion process, ultrathin nanoporous Bi2Se3 layers were epitaxially deposited on BiOCl nanosheets with strong electronic coupling, leading to hybrid electronic states with further bandgap narrowing. Such oriented nanoporous Bi2Se3 layers possessed largely exposed active edge sites, along with improved surface roughness and film forming ability even on inkjet-printed flexible electrodes. Superior room-temperature NO2 sensing performance was achieved compared to other 2D materials under bent conditions. Our work demonstrates that creating nanoscale features in 2D materials through topochemical heteroepitaxy is promising to achieve both favorable electronic properties and surface activity toward practical applications.

10.
Front Med (Lausanne) ; 9: 905902, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35935790

RESUMO

Port-wine stains (PWSs) are a congenital capillary malformed disorder and are caused by a number of somatic mutations that disrupt vascular development. However, the underlying genetic mutations in the pathogenesis of PWS have not yet been fully elucidated. To understand PWS genetic variations and investigate novel genetic mutations, we extracted genomic DNA from four sporadic PWS patients and then performed whole-genome sequencing (WGS). Using Sorting Intolerant from Tolerant (SIFT), PolyPhen2, Mutation Assessor, MetaSVM to identify candidate genetic mutations and whole-exome sequencing (WES) to confirm the identified variants. We found a previously reported G protein subunit alpha q (GNAQ) mutation c.548G > A, p.Arg183Gln in one case, whereas no such mutation was found in the other three samples. Moreover, six novel somatic mutations in three genes, including KCNJ12, SLC25A5, POTEE, were found in these four samples. Importantly, WES also verified the KCNJ12 (c.433G > A, p.Gly145Ser) and SLC25A5 (c.413G > A, p.Arg138His) mutations in other five sporadic PWS patients, with the frequency of 60% (3 of 5) and 40% (2 of 5), respectively. Thus, we reveal in this study two novel somatic mutations, KCNJ12 and SLC25A5, in the sporadic PWS patients for the first time. These findings highlight the genetic polymorphism of PWS and provide potential clinical prediction targets for this disease.

11.
Front Immunol ; 13: 948630, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35936006

RESUMO

N1-methyladenosine (m1A) is ubiquitous in eukaryotic RNA and regulates mRNA translation. However, little is known about its regulatory role in glioma. Here, we identified 4 m1A modification-related patterns based on m1A regulators in the TCGA (The Cancer Genome Atlas) and CGGA (Chinese Glioma Genome Atlas) cohorts. The differences in survival prognosis between different clusters were striking. In addition, stemness, genomic heterogeneity, tumor microenvironment (TME), and immune cell infiltration were also significantly different between the poor and best prognostic clusters. To reveal the underlying mechanism, differentially expressed genes (DEGs) between the poor and best prognostic clusters were identified, and then were integrated for weighted correlation network analysis (WGCNA). After Univariate Cox-LASSO-Multivariate Cox analyses, DEGs PLEK2 and ABCC3 were screened as the risk-hub genes and were selected to construct an m1A-related signature. Moreover, ABCC3 exacerbated glioma proliferation and was associated with temozolomide (TMZ) resistance. Overall, our study provided new insights into the function and potential therapeutic role of m1A in glioma.


Assuntos
Neoplasias Encefálicas , Glioma , Regulação Neoplásica da Expressão Gênica , Humanos , Metilação , RNA , Microambiente Tumoral/genética
12.
Biomaterials ; 287: 121638, 2022 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-35921729

RESUMO

Silk sericin, a natural protein extracted from silkworm cocoons, has been extensively studied and utilized in the biomedical field because of its superior biological activities and controllable chemical-physical properties. Sericin is biocompatible and naturally cell adhesive, enabling cell attachment, proliferation, and differentiation in sericin-based materials. Moreover, its abundant functional groups from variable amino acids composition allow sericin to be chemically modified and cross-linked to form versatile constructs serving as alternative matrixes for biomedical applications. Recently, sericin has been constructed into various types of biomaterials for tissue engineering and regenerative medicine, including various bulk constructions (films, hydrogels, scaffolds, conduits, and devices) and micro-nano formulations. In this review, we systemically summarize the properties of silk sericin, introduce its different forms, and demonstrate their newly-developed as well as potential biomedical applications.

14.
Plants (Basel) ; 11(15)2022 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-35956465

RESUMO

Many geometries of plant organs can be described by the Gielis equation, a polar coordinate equation extended from the superellipse equation, r=a|cosm4φ|n2+|1ksinm4φ|n3-1/n1. Here, r is the polar radius corresponding to the polar angle φ; m is a positive integer that determines the number of angles of the Gielis curve when φ ∈ [0 to 2π); and the rest of the symbols are parameters to be estimated. The pentagonal radial symmetry of calyxes and corolla tubes in top view is a common feature in the flowers of many eudicots. However, prior studies have not tested whether the Gielis equation can depict the shapes of corolla tubes. We sampled randomly 366 flowers of Vinca major L., among which 360 had five petals and pentagonal corolla tubes, and six had four petals and quadrangular corolla tubes. We extracted the planar coordinates of the outer rims of corolla tubes (in top view) (ORCTs), and then fitted the data with two simplified versions of the Gielis equation with k = 1 and m = 5: r=acos54φn2+sin54φn3-1/n1 (Model 1), and r=acos54φn2+sin54φn2-1/n1 (Model 2). The adjusted root mean square error (RMSEadj) was used to evaluate the goodness of fit of each model. In addition, to test whether ORCTs are radially symmetrical, we correlated the estimates of n2 and n3 in Model 1 on a log-log scale. The results validated the two simplified Gielis equations. The RMSEadj values for all corolla tubes were smaller than 0.05 for both models. The numerical values of n2 and n3 were demonstrated to be statistically equal based on the regression analysis, which suggested that the ORCTs of V. major are radially symmetrical. It suggests that Model 1 can be replaced by the simpler Model 2 for fitting the ORCT in this species. This work indicates that the pentagonal or quadrangular corolla tubes (in top view) can both be modeled by the Gielis equation and demonstrates that the pentagonal or quadrangular corolla tubes of plants tend to form radial symmetrical geometries during their development and growth.

15.
Polymers (Basel) ; 14(15)2022 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-35956674

RESUMO

To improve the dispersion stability of phenol-formaldehyde resin (PFR) particles in simulated oilfield injection water and their propagation ability in petroleum reservoir, a hydrophobically associating polymer (HAP) was employed as a stabilizer in this paper. The dispersion stability of PFR in the injection water was studied by measuring turbidity as a function of time. In addition, the migration property of the PFR/HAP dispersion was evaluated by both cellulose membrane filtration and sand packs-flooding experiments. The results show that HAP can stabilize the PFR dispersion prepared with the simulated injection water by forming PFR/HAP complex molecular aggregates. These aggregates can migrate in sand packs with strong flow resistance due to deformation or disaggregation of the aggregates when passing through the pore throat. Oil recovery was improved by up to 21.1% on the basis of water flooding, and the higher the concentration of PFR/HAP dispersion system, the better the oil recovery effect. Moreover, the cycle of log-jamming/dispersion of the aggregates leads to their penetrations through the bigger pores in the sand packs with a higher flow resistance than water. This process can improve the conformance of water in high permeability sand packs on a micro/macro scale and thus divert more water into low permeability sand packs. Therefore, more oil could be recovered from the low permeability sand packs. Moreover, the bigger the sand pack's permeability ratio, the lower the oil recovery rate by waterflood, and the more the incremental oil can be recovered by the PFR/HAP flood.

16.
Front Plant Sci ; 13: 964109, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35958212

RESUMO

Soil eutrophication from atmospheric deposition and fertilization threatens biodiversity and the functioning of terrestrial ecosystems worldwide. Increases in soil nitrogen (N) and phosphorus (P) content can alter the biomass and structure of plant communities in grassland ecosystems; however, the impact of these changes on plant-pollinator interactions is not yet clear. In this study, we tested how changes in flowering plant diversity and composition due to N and P enrichment affected pollinator communities and pollination interactions. Our experiments, conducted in a Tibetan alpine grassland, included four fertilization treatments: N (10 g N m-2 year-1), P (5 g P m-2 year-1), a combination of N and P (N + P), and control. We found that changes in flowering plant composition and diversity under the N and P treatments did not alter the pollinator richness or abundance. The N and P treatments also had limited effects on the plant-pollinator interactions, including the interaction numbers, visit numbers, plant and pollinator species dissimilarity, plant-pollinator interaction dissimilarity, average number of pollinator species attracted by each plant species (vulnerability), and average number of plant species visited by each pollinator species (generality). However, the N + P treatment increased the species and interaction dissimilarity in flowering plant and pollinator communities and decreased the generality in plant-pollinator interactions. These data highlight that changes in flowering plants caused by N + P enrichment alter pollination interactions between flowering plants and pollinators. Owing to changes in flowering plant communities, the plant-pollinator interactions could be sensitive to the changing environment in alpine regions.

17.
Front Cardiovasc Med ; 9: 944459, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35958417

RESUMO

Introduction: Desmin myopathy is a novel desmin (DES) indel mutation that causes severe atypical cardiomyopathy as well as atrioventricular block and skeletal myopathy. The mutation of the gene of the nodal tail causes myocardial injury. Rarely does desmin myopathy cause bilateral ventricular changes. Case presentation: We present a case of a 48-year-old man admitted with dyspnea and edema of both lower extremities. Due to bilateral lower limb weakness and calf muscle atrophy, gene sequencing was performed. The results showed that there was a pure missense mutation in the 8th exon region of the DES gene (c.1366G>A), encoding amino acid p.G456R (glycine>arginine). Supplementary examination suggests a high possibility of heart failure, atrial flutter, and desmin myopathy. Atrial flutter was treated by radiofrequency ablation. The clinical symptoms were stable after oral administration of rivaroxaban, coenzyme Q10, and ARNI. Conclusion: In our case, mutation results are the gold standard for the diagnosis of nodular myopathy. Cardiac magnetic resonance can define the extent and degree of cardiomyopathy and quantitatively evaluate cardiac function. At present, there is a lack of specific treatment for proteolytic myopathy. Therefore, the treatment for heart failure proves effective. Due to the multiple systems involved, early diagnosis and multidisciplinary management are critical to improving patient outcomes.

18.
Regen Biomater ; 9: rbac050, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35958518

RESUMO

Hydroxyapatite nanoparticles (HANPs) have been increasingly regarded and reported due to their potential anti-tumor ability. Previously, we found that the rod-like HANPs had good application potential for cutaneous melanoma (CMM). To satisfy the actual requirements in repairing post-operative skin defects and inhibiting CMM recurrence after tumorectomy, we constructed a novel chitosan/alginate (CS/Alg) hydrogel containing the aforementioned HANPs. The in vitro cell experiments confirmed that activated mitochondrial-dependent apoptosis was tightly related to the anti-tumor ability of HANPs. Specifically, we further discovered several target proteins might be involved in abnormal activating Wnt, proteoglycans in cancer, oxidative phosphorylation and p53 signaling pathways. The in vivo animal experiments demonstrated that the HANPs-loaded CS/Alg hydrogel (CS/Alg/HANPs) had a similar effect on inhibiting tumor growth as HANPs, and CS/Alg hydrogel as well as phosphate buffered saline (PBS) group (control) not showed any effect, proving the key role of HANPs. The immunohistochemical staining demonstrated a tumor inhibition via the mitochondria-mediated apoptosis pathway, consistent with the in vitro evaluation. Moreover, CS/Alg/HANPs exhibited no additional biosafety risk to the functions of major organs. Overall, this CS/Alg/HANPs hydrogel has substantial application potential for treating CMM.

19.
Front Hum Neurosci ; 16: 906123, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35959240

RESUMO

Research showed that action real-time strategy gaming (ARSG) experience is related to cognitive and neural plasticity, including visual selective attention and working memory, executive control, and information processing. This study explored the relationship between ARSG experience and information transmission in the auditory channel. Using an auditory, two-choice, go/no-go task and lateralized readiness potential (LRP) as the index to partial information transmission, this study examined information transmission patterns in ARSG experts and amateurs. Results showed that experts had a higher accuracy rate than amateurs. More importantly, experts had a smaller stimulus-locked LRP component (250 - 450 ms) than amateurs on no-go trials, while the response-locked LRP component (0 - 300 ms) on go trials did not differ between groups. Thus, whereas amateurs used an asynchronous information transmission pattern, experts used a reduced asynchronous information transmission pattern or a synchronous pattern where most of processing occurred prior to response execution - an information transmission pattern that supports rapid, error-free performance. Thus, experts and amateurs may use different information transmission patterns in auditory processing. In addition, the information transmission pattern used by experts is typically observed only after long-term auditory training according to past research. This study supports the relationship between ARSG experience and the development of information processing patterns.

20.
Nat Commun ; 13(1): 4615, 2022 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-35941158

RESUMO

Understanding the impact of age on vaccinations is essential for the design and delivery of vaccines against SARS-CoV-2. Here, we present findings from a comprehensive analysis of multiple compartments of the memory immune response in 312 individuals vaccinated with the BNT162b2 SARS-CoV-2 mRNA vaccine. Two vaccine doses induce high antibody and T cell responses in most individuals. However, antibody recognition of the Spike protein of the Delta and Omicron variants is less efficient than that of the ancestral Wuhan strain. Age-stratified analyses identify a group of low antibody responders where individuals ≥60 years are overrepresented. Waning of the antibody and cellular responses is observed in 30% of the vaccinees after 6 months. However, age does not influence the waning of these responses. Taken together, while individuals ≥60 years old take longer to acquire vaccine-induced immunity, they develop more sustained acquired immunity at 6 months post-vaccination. A third dose strongly boosts the low antibody responses in the older individuals against the ancestral Wuhan strain, Delta and Omicron variants.


Assuntos
COVID-19 , Vacinas Virais , Idoso , Anticorpos Antivirais , Formação de Anticorpos , Vacina BNT162 , COVID-19/prevenção & controle , Vacinas contra COVID-19 , Humanos , Pessoa de Meia-Idade , SARS-CoV-2 , Vacinação , Vacinas Sintéticas , Vacinas de mRNA
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