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1.
Sci China Life Sci ; 2022 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-35524910

RESUMO

Autologous fat-derived stromal vascular fraction (SVF) is a mixed cell population that has been used for many years in regenerative plastic surgery. In terms of animal and clinical research, this concise review was performed to evaluate the efficacy of SVF in knee degenerative joint disease (KDJD), which could cause pain, disability and severely affect patients' lives. Thirteen studies retrieved and screened from the databases were included, including six animal studies and seven clinical trials. The meta-analysis of clinical research shows that intra-articular injection of SVF, in combination with adjuvant surgery, could alleviate pain and improve early functional recovery for patients with KDJD at Kellgren-Lawrence (KL) grades II-III.

2.
Front Genet ; 13: 864383, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35571068

RESUMO

In recent years, methylation modification regulators have been found to have essential roles in various tumor mechanisms. However, the relationships between N6-methyladenosine (m6A) and 5-methylcytosine (m5C) regulators and clear cell renal cell carcinoma (ccRCC) remain unknown. This study investigated these relationships using the data from The Cancer Genome Atlas database. We calculated risk scores using a Lasso regression analysis and divided the patient samples into two risk groups (tumor vs. normal tissues). Furthermore, we used univariate and multivariate Cox analyses to determine independent prognostic indicators and explore correlations between the regulatory factors and immune infiltrating cell characteristics. Finally, quantitative reverse transcriptase-polymerase chain reaction (PCR) and The Human Protein Atlas were used to verify signature-related gene expression in clinical samples. We identified expression differences in 35 regulatory factors between the tumor and normal tissue groups. Next, we constructed a five-gene risk score signature (NOP2 nucleolar protein [NOP2], methyltransferase 14, N6-adenosine-methyltransferase subunit [METTL14], NOP2/Sun RNA methyltransferase 5 [NSUN5], heterogeneous nuclear ribonucleoprotein A2/B1 [HNRNPA2B1], and zinc finger CCCH-type containing 13 [ZC3H13]) using the screening criteria (p < 0.01), and then divided the cases into high- and low-risk groups based on their median risk score. We also screened for independent prognostic factors related to age, tumor grade, and risk score. Furthermore, we constructed a Norman diagram prognostic model by combining two clinicopathological characteristics, which demonstrated good prediction efficiency with prognostic markers. Then, we used a single-sample gene set enrichment analysis and the cell-type identification by estimating relative subsets of RNA transcripts (CIBERSORT) method to evaluate the tumor microenvironment of the regulatory factor prognostic characteristics. Moreover, we evaluated five risk subgroups with different genetic signatures for personalized prognoses. Finally, we analyzed the immunotherapy and immune infiltration response and demonstrated that the high-risk group was more sensitive to immunotherapy than the low-risk group. The PCR results showed that NSUN5 and HNRNPA2B1 expression was higher in tumor tissues than in normal tissues. In conclusion, we identified five m6A and m5C regulatory factors that might be promising biomarkers for future research.

3.
Pathol Res Pract ; 235: 153943, 2022 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-35576836

RESUMO

OBJECTIVE: Breast cancer (BC) is the most commonly diagnosed cancer among females and has a poor prognosis, breast invasive ductal carcinoma is the most common histological type. The occurrence and development of BC is closely related to aberrant glucose metabolism. In the hyperglycemic environment caused by abnormal glucose metabolism, hypoxia-inducible factor-1 alpha (HIF-1α) enables tumor cells to absorb large amounts of glucose and enhance glycolysis by inducing the expression of glucose transporter type1 (GLUT1) and glycolysis genes, thus promoting tumor cell proliferation and metastasis. Mitochondrial Sirtuin5 (SIRT5) plays a role in the rewiring of glucose metabolism during the progression of cancers. Thus, we aimed to elucidate whether SIRT5 promotes BC proliferation and metastasis by facilitating aerobic glycolysis in BC. METHODS: The expression of SIRT5 in breast carcinoma tissue and cells was evaluated using immunohistochemical staining, western blot and quantitative reverse transcription-polymerase chain reaction (qRT-PCR) analysis to confirm the biological role of SIRT5 in breast carcinoma. We established a stable cell line with SIRT5 knockdown using lentiviral transduction in T47D cells to reduce SIRT5 expression and then evaluated the effect of SIRT5 on cells cultured in the presence of high glucose (4500 mg/L) and normal glucose (2000 mg/L) concentrations. Cell proliferation was detected using the CCK-8 assay, the cell cycle and cell apoptosis were measured using flow cytometry and Annexin V staining, and cell migration was tested by performing Celigo scratch and Transwell assays. The expression of PKM2, HK2, mTOR and HIF-1α, which play roles in aerobic glycolysis, was investigated using western blot. RESULTS: SIRT5 was overexpressed in BC tissues compared with paired normal tissues. Prognostic and OS analyses showed that the SIRT5 expression level was an individual prognostic factor for patients with BC. SIRT5 knockdown inhibited proliferation and metastasis and slightly increased apoptosis in T47D cells under high-glucose conditions. Furthermore, the downregulation of HK2 and HIF-1α caused by SIRT5 knockdown was a high glucose-dependent process, while the downregulation of PKM2 was mediated by a high glucose-independent process. CONCLUSIONS: SIRT5 is an independent prognostic factor for BC and contributes to cell proliferation and metastasis in a high glucose-dependent manner to some degree, which might be mediated by promoting aerobic glycolysis.

4.
J Transl Med ; 20(1): 214, 2022 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-35562754

RESUMO

In recent years, 5-methylcytosine (m5C) RNA modification has emerged as a key player in regulating RNA metabolism and function through coding as well as non-coding RNAs. Accumulating evidence has shown that m5C modulates the stability, translation, transcription, nuclear export, and cleavage of RNAs to mediate cell proliferation, differentiation, apoptosis, stress responses, and other biological functions. In humans, m5C RNA modification is catalyzed by the NOL1/NOP2/sun (NSUN) family and DNA methyltransferase 2 (DNMT2). These RNA modifiers regulate the expression of multiple oncogenes such as fizzy-related-1, forkhead box protein C2, Grb associated-binding protein 2, and TEA domain transcription factor 1, facilitating the pathogenesis and progression of cancers. Furthermore, the aberrant expression of methyltransferases have been identified in various cancers and used to predict the prognosis of patients. In this review, we present a comprehensive overview of m5C RNA methyltransferases. We specifically highlight the potential mechanism of action of m5C in cancer. Finally, we discuss the prospect of m5C-relative studies.

5.
Nano Lett ; 2022 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-35536749

RESUMO

Monolayer hexagonal boron nitride (hBN) has attracted interest as an ultrathin tunnel barrier or environmental protection layer. Recently, wafer-scale hBN growth on Cu(111) was developed for semiconductor chip applications. For basic research and technology, understanding how hBN perturbs underlying electronically active layers is critical. Encouragingly, hBN/Cu(111) has been shown to preserve the Cu(111) surface state (SS), but it was unknown how tunneling into this SS through hBN varies spatially. Here, we demonstrate that the Cu(111) SS under wafer-scale hBN is homogeneous in energy and spectral weight over nanometer length scales and across atomic terraces. In contrast, a new spectral feature─not seen on bare Cu(111)─varies with atomic registry and shares the spatial periodicity of the hBN/Cu(111) moiré. This work demonstrates that, for some 2D electron systems, an hBN overlayer can act as a protective yet remarkably transparent window on fragile low-energy electronic structure below.

6.
Entropy (Basel) ; 24(4)2022 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-35455120

RESUMO

This work proposes a new computational framework for learning a structured generative model for real-world datasets. In particular, we propose to learn a Closed-loop Transcriptionbetween a multi-class, multi-dimensional data distribution and a Linear discriminative representation (CTRL) in the feature space that consists of multiple independent multi-dimensional linear subspaces. In particular, we argue that the optimal encoding and decoding mappings sought can be formulated as a two-player minimax game between the encoder and decoderfor the learned representation. A natural utility function for this game is the so-called rate reduction, a simple information-theoretic measure for distances between mixtures of subspace-like Gaussians in the feature space. Our formulation draws inspiration from closed-loop error feedback from control systems and avoids expensive evaluating and minimizing of approximated distances between arbitrary distributions in either the data space or the feature space. To a large extent, this new formulation unifies the concepts and benefits of Auto-Encoding and GAN and naturally extends them to the settings of learning a both discriminative and generative representation for multi-class and multi-dimensional real-world data. Our extensive experiments on many benchmark imagery datasets demonstrate tremendous potential of this new closed-loop formulation: under fair comparison, visual quality of the learned decoder and classification performance of the encoder is competitive and arguably better than existing methods based on GAN, VAE, or a combination of both. Unlike existing generative models, the so-learned features of the multiple classes are structured instead of hidden: different classes are explicitly mapped onto corresponding independent principal subspaces in the feature space, and diverse visual attributes within each class are modeled by the independent principal components within each subspace.

7.
Nutrients ; 14(8)2022 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-35458236

RESUMO

BACKGROUND: Iron overload is drawing attention in the development of knee osteoarthritis (OA). To identify the modifiable risk factors for iron-related pathological conditions, we examined the association between iron intake and the risk of knee OA progression. METHODS: A total of 1912 participants in the Osteoarthritis Initiative (OAI), aged 45-79 years and with at least one knee radiographic OA at baseline, were identified and were followed up to 6 years. The iron and other nutrient intake was measured by the validated Block Brief 2000 Food Frequency Questionnaire. The outcome measures were by radiographic progression on the basis of the Kellgren-Lawrence (KL) grade and the joint-space-narrowing (JSN) score. The association between the iron intake and the knee OA progression was examined by Cox proportional hazards models and restricted cubic spline (RCS) regression. RESULTS: Among the study participants, 409 participants experienced KL-grade progression, and 684 participants experienced JSN-score progression within 6 years. Overall, the association between iron intake and the risk of KL-grade progression followed a U shape (p for nonlinearity < 0.001). The risk of KL-grade progression was significantly lower in participants with iron intakes of <16.5 mg/day (per mg/day: adjusted hazard ratio (HR), 0.75; 95% CI (confidence interval), 0.64-0.89), and it was higher in those with iron intakes ≥16.5 mg/day (per mg/day: HR, 1.20; 95% CI, 1.04-1.38). Consistently, when the iron intake was assessed as deciles, compared to those in Deciles 3-5 (10.9-23.3 mg/day), the risk of KL-grade progression was higher for Deciles 1-2 (≤10.9 mg/day: HR, 1.57; 95% CI, 1.17-2.10) and for Deciles 6-10 (>23.3 mg/day: adjusted HR, 1.60; 95% CI, 1.19-2.16). Similar U-shaped relations were found for iron intake with the risk of JSN-score progression (p for nonlinearity = 0.035). CONCLUSIONS: There was a U-shaped association between the iron intake and the progression of knee OA, with an inflection point at about 16.5 mg/day, and minimal risk from 10.9 to 23.3 mg/day of iron intake. An appropriate iron intake was advisable for knee OA, whereas excessive or deficient iron intake increased the risk of knee OA progression.


Assuntos
Osteoartrite do Joelho , Progressão da Doença , Humanos , Ferro , Articulação do Joelho/diagnóstico por imagem , Articulação do Joelho/patologia , Osteoartrite do Joelho/diagnóstico por imagem , Osteoartrite do Joelho/etiologia , Osteoartrite do Joelho/patologia , Fatores de Risco
8.
Artigo em Inglês | MEDLINE | ID: mdl-35409966

RESUMO

Volume-based drug purchasing by China's health insurance system currently represents the largest group purchasing organization worldwide. After exchanging the market that accounted for nearly half of the volume of the healthcare system for the ultra-low-price supply of limited drugs, what are the effects on patient and funding burdens, drug accessibility, and clinical efficacy? We aimed to verify the effectiveness of the policy, explore the reasons behind the problem and identify regulatory priorities and collaborative measures. We used literature and reported data from 2019 to 2021 to conduct a stakeholder analysis and health impact assessment, presenting the benefit and risk share for various dimensions. The analysis method was a multidimensional scaling model, which visualized problematic associations. Seventy-nine papers (61 publications and 18 other resources) were included in the study, with 22 effects and 36 problems identified. The results indicated favorable affordability and poor accessibility of drugs, as well as high risk of reduced drug quality and drug-use rationality. The drug-use demand of patients was guaranteed; the prescription rights of doctors regarding clinical drug use were limited; unreasonable evaluation indicators limited the transformation of public hospitals to value- and service-oriented organizations; the sustainability of health insurance funds and policy promotion were at risk; and innovation by pharmaceutical companies was accelerated. The problems associated with high co-occurrence frequencies were divided into the following clusters: cost control, drug accessibility, system rationality, policy fairness, drug quality, and moral hazards. These findings suggested that China has achieved short-term success in reducing the burden on patients and reducing fund expenditure. However, there were still deficiencies in guaranteed supply, quality control, and efficacy tracking. The study offers critical lessons for China and other low- and middle-income countries.


Assuntos
Comportamento do Consumidor , Gastos em Saúde , China , Controle de Custos , Humanos , Seguro Saúde
9.
J Healthc Eng ; 2022: 8508943, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35469227

RESUMO

To evaluate the efficacy and safety of endoscopic retrograde cholangiopancreatography (ERCP) in the treatment of patients with symptomatic pancreas divisum (PD) and to discuss the possible risk factors of endoscopic reintervention for symptomatic PD. A total of 50 patients with symptomatic PD who underwent ERCP from January 2010 to December 2019 were finally brought into study. All patients were divided into the nonage and the adult group according to their ages. Meanwhile, all patients were also divided into the intervention and the reintervention group according to times of ERCP. The long-term outcome of each patient was collected during the follow-up by phone call. The total success rate of ERCP was 94.7% (89/93), and the effective rate of first ERCP was 58% (29/50). There were no statistical differences on the outcomes of ERCP treatment between the adult and nonage group. There were 17 patients with complete pancreas divisum and 19 patients with chronic pancreatitis in the reintervention group, which were more than 6 patients and 8 patients in the intervention group (P < 0.05). In bivariate regression analysis, chronic pancreatitis and complete pancreas divisum might be significant risk factors for endoscopic reintervention for patients with symptomatic PD (OR, 8.010, 95% CI, 1.483-43.276, P=0.016; OR, 8.869, 95% CI, 1.450-54.254, P=0.018, respectively). ERCP in treating adult and nonage patients with symptomatic PD are effective and safe. But, many patients may need endoscopic reintervention. Complete pancreas divisum and chronic pancreatitis may be risk factors of ERCP reintervention for patients with symptomatic PD.


Assuntos
Pâncreas , Pancreatite Crônica , Adulto , Colangiopancreatografia Retrógrada Endoscópica/efeitos adversos , Humanos , Pâncreas/diagnóstico por imagem , Pâncreas/cirurgia , Pancreatite Crônica/etiologia , Pancreatite Crônica/cirurgia
10.
Foods ; 11(7)2022 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-35407089

RESUMO

Tamarix ramosissima has been widely used as barbecue skewers for the good taste and unique flavor it gives to the meat, but the effects of T. ramosissima on heterocyclic amine (HA) formation in roast lamb are unknown. The influence of T. ramosissima extract (TRE) on HA formation, precursors' consumption, and free radicals' generation in roast lamb patties were elucidated by UPLC-MS, HPLC, and electron spin resonance (ESR) analysis, respectively. Six HAs were identified and compared with the control group; the total and polar HAs decreased by 30.51% and 56.92% with TRE addition at 0.30 g/kg. The highest inhibitory effect was found against 2-amino-1-methyl-6-phenylimidazo[4,5-f]pyridine (PhIP) formation (70.83%) at 0.45 g/kg. The addition of TRE retarded the consumption of HA precursors, resulting in fewer HAs formed. The typical signal intensity of free radicals in roast lamb patties significantly decreased with TRE addition versus the control group (p < 0.05), and the higher the levels of the TRE, the greater the decrease in signal intensity. We propose that the inhibitory effects of TRE on HA formation, especially on polar HAs, were probably achieved by retarding the consumption of precursors and preventing free radicals from being generated in roast lamb patties. These findings provide valuable information concerning TRE's effectiveness in preventing HA formation through both the precursor consumption and free radical scavenging mechanisms.

12.
Front Immunol ; 13: 840755, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35296088

RESUMO

Psoriasis is a chronic skin disorder associated with multiple sequelae, such as psoriatic arthritis and cardiovascular diseases. Increasing evidence has shown that γδ T cells, as sources of IL-17A, play critical roles in psoriatic inflammations. However, there still lack effective ways to manipulate these pathogenic γδ T cells, which are less well studied than αß T cells. The present study aims to characterize the phenotype of γδ T cells and evaluate the impact of D-mannose (a C-2 epimer of glucose) on γδ T cell-mediated psoriasis. We found that skin-draining LN γδ T cells underwent robust proliferation and acquired an IL-17-producing phenotype during psoriasis. The transcriptomic profiles of these psoriatic γδ T cells had elevated glycolytic signatures. Importantly, D-mannose treatment suppressed the γδ T cell reaction and successfully alleviated the local and systematic inflammation induced by imiquimod. The decreased AKT/mTOR/HIF-1α signaling and glycolytic ability may contribute to the suppression of γδ T cells achieved by D-mannose. Our study increased understanding of γδ T cells in psoriasis and promoted D-mannose utilization as a potential clinical application for autoimmune diseases driven by γδ T cells.


Assuntos
Linfócitos Intraepiteliais , Psoríase , Animais , Imiquimode/farmacologia , Inflamação , Manose , Camundongos , Pele
13.
Pathol Res Pract ; 232: 153841, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35303522

RESUMO

BACKGROUND: Esophageal squamous cell carcinoma (ESCC) is a multifactorial disease and the sixth leading cause of death from cancer worldwide. Patients with ESCC usually have a short survival period due to the late stage at diagnosis. Incidence rates of ESCC remain high among the elderly. With recent advances, it has been demonstrated that ESCC tumors display a unique genetic profile. This study aimed to examine the possible function of OTX1 in ESCC. METHODS: We collected paraffin-embedded tumor tissues from 107 patients originally diagnosed with ESCC at Xijing Hospital and fresh-harvested and paired adjacent normal esophageal tissues from 15 ESCC patients undergoing curative resection. The expression level of OTX1 was evaluated through immunohistochemistry and western blot. Prognostic and survival analyses were conducted using univariate/multivariate analysis and log-rank analysis with SPSS 23.0. Cell models and xenograft models were used to examine the overexpression of OTX1 in vivo and in vitro. RESULTS: OTX1 was overexpressed in ESCC tissues compared with normal esophageal tissues. Both the mRNA expression level and protein level of OTX1 were higher than they were in paired normal tissue. Prognostic and OS analyses showed that the OTX1 expression level was an individual prognostic factor in ESCC patients. Cell viability was significantly promoted when OTX1 was overexpressed in ESCC cell, Furthermore, downregulating OTX1 in EC109 cell significantly attenuated the cell proliferation migration and invasion. Flow cytometric detection showed that cells overexpressing OTX1 were predominantly in the S and G2&M phases. In the xenograft model, both tumor size and weight in the OTX1 overexpression group were significantly larger than those in the control group. CONCLUSION: OTX1 is an independent prognostic factor of ESCC and contributes to tumorigenesis both in vivo and in vitro.


Assuntos
Carcinoma de Células Escamosas , Neoplasias Esofágicas , Carcinoma de Células Escamosas do Esôfago , Idoso , Biomarcadores Tumorais/metabolismo , Carcinogênese/genética , Carcinoma de Células Escamosas/patologia , Linhagem Celular Tumoral , Proliferação de Células/genética , Neoplasias Esofágicas/patologia , Carcinoma de Células Escamosas do Esôfago/patologia , Regulação Neoplásica da Expressão Gênica , Humanos , Fatores de Transcrição Otx/genética , Fatores de Transcrição Otx/metabolismo , Prognóstico
14.
Cancers (Basel) ; 14(5)2022 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-35267472

RESUMO

Thyroid carcinoma is the most prevalent endocrine cancer globally and the primary cause of cancer-related mortality. Epigenetic modifications are progressively being linked to metastasis. This study aimed to examine whole-genome DNA methylation patterns and the gene expression profiles in thyroid cancer tissue samples using a MethylationEPIC BeadChip (850K), RNA sequencing, and a targeted bisulfite sequencing assay. The results of the Illumina Infinium human methylation kit (850K) analyses identified differentially methylated CpG locations (DMPs) and differentially methylated CpG regions (DMRs) encompassing nearly the entire genome with high resolution and depth. Gene ontology and KEGG pathway analyses revealed that the genes associated with DMRs belonged to various domain-specific ontologies, including cell adhesion, molecule binding, and proliferation. The RNA-Seq study found 1627 differentially expressed genes, 1174 of which that were up-regulated and 453 of which that were down-regulated. The targeted bisulfite sequencing assay revealed that CHST2, DPP4, DUSP6, ITGA2, SLC1A5, TIAM1, TNIK, and ABTB2 methylation levels were dramatically lowered in thyroid cancer patients when compared to the controls, but GALNTL6, HTR7, SPOCD1, and GRM5 methylation levels were significantly raised. Our study revealed that the whole-genome DNA methylation patterns and gene expression profiles in thyroid cancer shed new light on the tumorigenesis of thyroid cancer.

15.
Microbiol Spectr ; 10(2): e0105221, 2022 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-35311572

RESUMO

The CD2-like (CD2V) protein is a crucial antigen of African swine fever virus (ASFV). CD2V interacts with the cellular AP-1 protein, participates in intracellular transport of virus, and induces neutralizing antibodies to partly protect swine from virus attack. In this study, a specific CD2V dimeric protein was designed to enhance antigenicity and immunogenicity, expressed in a Bac-to-Bac baculovirus expression vector system and purified by Ni-affinity chromatography. After animal immunization, five monoclonal antibodies (mAbs) (7E12, 22B3, 18A3, 13G11, and 43C2) against CD2V were developed. The variable regions of heavy chains and light chains of the mAbs were sequenced to prove that the five mAbs differed from one another. The mAbs of CD2V could combine with ASFV by immunoperoxidase monolayer assay (IPMA). B cell epitopes of CD2V were screened using the five mAbs by indirect enzyme-linked immunosorbent assay (ELISA) and Dot-ELISA. Therefore, three B cell epitopes (147FVKYT151, 157EYNWN161, and 195SSNY198) were identified. This is the first time that mAbs of the ASFV CD2V protein have been developed and the sequencing of heavy chains and light chains of mAbs has been completed. Linear B cell epitopes, which were core targets of immunoprotection of the CD2V protein, were identified by mAbs for the first time. This study provides efficient epitopes for the development of ASFV subunit vaccines. IMPORTANCE The ASFV CD2V protein is a crucial antigen on the outer envelopes of virus particles. A modified ASFV CD2V dimeric protein was expressed in the Bac-to-Bac baculovirus expression vector system. Five monoclonal antibodies (mAbs) against CD2V were developed, sequenced, and applied to identify CD2V protein B cell epitopes. Three B cell epitopes, 147FVKYT151, 157EYNWN161, and 195SSNY198, were identified. This is the first time CD2V mAbs have been developed, the sequencing of heavy chains and light chains of CD2V mAbs have been completed, and CD2V B cell epitopes have been identified by using scanning peptide method and bioinformatics methods.


Assuntos
Vírus da Febre Suína Africana , Febre Suína Africana , Febre Suína Africana/prevenção & controle , Vírus da Febre Suína Africana/genética , Vírus da Febre Suína Africana/metabolismo , Animais , Anticorpos Monoclonais , Anticorpos Antivirais , Antígenos Virais , Epitopos de Linfócito B/genética , Epitopos de Linfócito B/metabolismo , Suínos
16.
J Am Chem Soc ; 144(12): 5247-5252, 2022 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-35298886

RESUMO

Understanding the structural nature of the active sites in electrocatalysis is central to discovering general design rules for better catalysts in fuel cells and electrolyzers. Nanostructures are widely used as electrocatalysts, but the location and structure of the active sites within the nanostructure are often unknown. This information is hidden in conventional bulk measurements due to ensemble averaging, hindering direct structure-activity correlation. Herein, we use a single-entity electrochemical approach to reveal the heterogeneity in electrocatalysts via scanning electrochemical cell microscopy (SECCM). Using hematite (α-Fe2O3) nanorods as the model catalyst for oxygen evolution reaction (OER), the electrocatalytic activity is measured at individual nanorods. Finer mapping within a single nanorod shows that the OER activity is consistently higher at the body portion vs the tip of the nanorod. Our results directly suggest the benefit of synthesizing longer hematite nanorods for better OER performance. The origin of the enhanced local activity is explained by the larger fraction of {001} facet exposed on the body compared to the tip. The finding goes beyond OER on hematite nanorods, highlighting the critical role of single-entity activity mapping and colocalized structural characterization in revealing active sites in electrocatalysis.

17.
Pathol Res Pract ; 232: 153838, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35278816

RESUMO

BACKGROUND: The main pathological change causing carotid artery stenosis is atherosclerosis, and studies suggest that tumor necrosis factor-stimulated gene-6 (TSG-6) has an anti-atherogenic effect and may be a new target for the diagnosis of carotid artery stenosis disease. We hypothesized that serum TSG-6 levels might also be associated with carotid artery stenosis. The aim of this study was to evaluate the diagnostic significance and potential predictive value of serum TSG-6 levels in patients with severe carotid artery stenosis and symptomatic stenosis. METHODS: Serum TSG-6 levels were measured in 96 patients with carotid stenosis and 40 sex and age matched control healthy subjects. The expression of TSG-6 in carotid plaques (4 severe stenoses, 4 moderate stenoses, and 4 mild stenoses) and 4 superficial temporal artery vascular tissues of 12 patients with carotid stenosis who underwent endarterectomy at our hospital were detected by Western blot. Histological analysis of carotid plaque and superficial temporal artery tissues was also performed. RESULTS: Compared with controls, serum TSG-6 levels were higher in patients with carotid stenosis, TSG-6 expression was increased in tissues with moderate and severe stenosis, and TSG-6 expression was significantly higher in the fibrous cap component of the plaque than in the non-fibrous cap component. Serum TSG-6 levels were higher in patients with symptomatic stenosis than in patients with asymptomatic stenosis. Tissue TSG-6 staining levels and serum TSG-6 levels were positively correlated (r = 0.694, p < 0.05) and tissue TSG-6 staining levels were positively correlated with macrophage staining levels (r = 0.932, p < 0.05). Logistic regression analysis showed that serum TSG-6 was an independent factor for the presence of severe carotid stenosis and symptomatic stenosis in patients (p < 0.001). Serum TSG-6 levels were more diagnostically efficient than other indices in identifying severe and symptomatic carotid stenosis (p < 0.05), especially in identifying symptomatic stenosis (p < 0.01). We further significantly increased the diagnostic power of symptomatic stenosis using a combined model of serum TSG-6 and homocysteine (p < 0.05). CONCLUSIONS: Serum TSG-6 may serve as a new non-invasive and easily measured biomarker to better screen people with severe and symptomatic carotid stenosis in clinical practice.


Assuntos
Estenose das Carótidas , Moléculas de Adesão Celular , Placa Aterosclerótica , Biomarcadores , Artérias Carótidas/patologia , Estenose das Carótidas/complicações , Estenose das Carótidas/diagnóstico , Estenose das Carótidas/patologia , Moléculas de Adesão Celular/sangue , Humanos , Placa Aterosclerótica/diagnóstico , Placa Aterosclerótica/patologia , Fatores de Necrose Tumoral
18.
Arthroscopy ; 2022 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-35157969

RESUMO

PURPOSE: To evaluate various radiofrequency ablation (RFA) treatments for knee osteoarthritis (OA) and determine the best modality, target, number of electrodes, and image guidance for improving knee pain and function. METHODS: Electronic databases were searched for randomized controlled trials (RCTs) comparing the efficacy of RFA treatments for knee OA from inception up to September 30, 2021. The primary outcome was the visual analog scale (VAS), and the secondary outcome was the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC). Bayesian network meta-analysis was performed to synthesize the mean difference (MD) and rank the comparative effectiveness of treatments. RESULTS: A total of 21 eligible RCTs (from 2011 to 2021, involving 1,818 patients) with 8 RFA treatments, 6 intra-articular injections, NSAIDS, exercise, and placebo were assessed. Conventional bipolar genicular nerve RFA (GNRFA) had the greatest net benefit on the VAS at 6 months (MD, -5.5; 95% confidence interval [CI], -4.3 to -6.7; SUCRA, .98). And cooled monopolar GNRFA had the greatest net benefit on the WOMAC at 6 months (MD, -33; 95% CI, -37 to -29; SUCRA, .99). In conventional and pulsed modalities, bipolar RFA was associated with a significant decrease in VAS and WOMAC than monopolar RFA. Combining pulsed intra-articular RFA and platelet-rich plasma injection had no additional positive effects on VAS or WOMAC at 3 months. CONCLUSIONS: RFA is effective in improving both knee pain and function in patients with OA, at least in the short term (6 months). Patients respond better to the cooled modality than the conventional and pulsed modalities. Bipolar is more effective than monopolar for improving pain and function in conventional and pulsed modalities. Fluoroscopy and ultrasound guidance showed no differences in improving pain and function. The effectiveness of RFA in cooled modality using bipolar or in combination with various intra-articular injections remains to be compared. LEVEL OF EVIDENCE: II, systematic review and meta-analysis of Level I and II studies.

19.
Dalton Trans ; 51(11): 4414-4422, 2022 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-35195129

RESUMO

With the increasing demand for new inorganic functional materials, more and more attention is paid to rare earth ion doped luminescent materials. In this work, an Eu2+ doped Ba4La6O(SiO4)6 phosphor was synthesized by the high temperature solid-phase method. In the phosphor, two Ba2+ sites could be occupied by Eu2+ cations to provide two different kinds of coordination environments, resulting in broad emitting bands in the range of 450-630 nm and ultra-wide excitation bands in the range of 250-500 nm. The presence of two different Eu2+ emitting centers is verified by measuring the photoluminescence spectra and decay curves in Ba4La6O(SiO4)6 phosphors. The temperature dependence of emission intensity and full width at half maximum of Eu2+ in the range of 293-453 K were investigated systematically. The substitution of Ba2+ by Sr2+ can adjust the crystal field; thus, the luminous intensity was improved by 2.07 times and T50 was increased from 380 K to 453 K. Due to the Sr2+ ion doping, some of the Eu3+ ions cannot be reduced and remain in the trivalent state. In addition, by integrating the as-prepared Ba1.42Sr2.5La6O(SiO4)6:Eu phosphor, commercial blue and red phosphors, and a 385 nm LED chip, a white-LED lamp was made, which realized an applicable color rendering index (Ra = 94.6). For the Ba0.42Sr3.5La6O(SiO4)6 phosphor, the emission can be shifted from yellow to green and to yellow by excitation wavelength variation from 250 to 360 and 480 nm, which proves that the phosphor is a promising candidate for anti-counterfeiting applications.

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