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1.
Nat Immunol ; 25(3): 525-536, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38356061

RESUMO

Regulatory T (Treg) cells are critical for immune tolerance but also form a barrier to antitumor immunity. As therapeutic strategies involving Treg cell depletion are limited by concurrent autoimmune disorders, identification of intratumoral Treg cell-specific regulatory mechanisms is needed for selective targeting. Epigenetic modulators can be targeted with small compounds, but intratumoral Treg cell-specific epigenetic regulators have been unexplored. Here, we show that JMJD1C, a histone demethylase upregulated by cytokines in the tumor microenvironment, is essential for tumor Treg cell fitness but dispensable for systemic immune homeostasis. JMJD1C deletion enhanced AKT signals in a manner dependent on histone H3 lysine 9 dimethylation (H3K9me2) demethylase and STAT3 signals independently of H3K9me2 demethylase, leading to robust interferon-γ production and tumor Treg cell fragility. We have also developed an oral JMJD1C inhibitor that suppresses tumor growth by targeting intratumoral Treg cells. Overall, this study identifies JMJD1C as an epigenetic hub that can integrate signals to establish tumor Treg cell fitness, and we present a specific JMJD1C inhibitor that can target tumor Treg cells without affecting systemic immune homeostasis.


Assuntos
Doenças Autoimunes , Humanos , Citocinas , Epigenômica , Histona Desmetilases , Homeostase , Oxirredutases N-Desmetilantes , Histona Desmetilases com o Domínio Jumonji/genética
2.
Emerg Infect Dis ; 30(6): 1218-1222, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38640498

RESUMO

We characterized the evolution and molecular characteristics of avian influenza A(H7N9) viruses isolated in China during 2021-2023. We systematically analyzed the 10-year evolution of the hemagglutinin gene to determine the evolutionary branch. Our results showed recent antigenic drift, providing crucial clues for updating the H7N9 vaccine and disease prevention and control.


Assuntos
Antígenos Virais , Evolução Molecular , Glicoproteínas de Hemaglutininação de Vírus da Influenza , Subtipo H7N9 do Vírus da Influenza A , Influenza Aviária , Influenza Humana , Filogenia , Subtipo H7N9 do Vírus da Influenza A/genética , Subtipo H7N9 do Vírus da Influenza A/imunologia , China/epidemiologia , Animais , Influenza Aviária/virologia , Influenza Aviária/epidemiologia , Glicoproteínas de Hemaglutininação de Vírus da Influenza/genética , Glicoproteínas de Hemaglutininação de Vírus da Influenza/imunologia , Humanos , Influenza Humana/epidemiologia , Influenza Humana/virologia , Influenza Humana/imunologia , Antígenos Virais/imunologia , Antígenos Virais/genética , Aves/virologia , Variação Antigênica
3.
FASEB J ; 37(11): e23227, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37792678

RESUMO

Lipophagy is a subset of selective autophagy that specifically degrades lipid droplets and plays an important role in obesity. Leflunomide treatment in rheumatoid arthritis (RA) patients has been associated with weight loss and decreased blood glucose levels, which cannot be attributed to its known side effects. Our prior studies showed that A77 1726, the active metabolite of leflunomide, acts as an inhibitor of S6K1 to sensitize the insulin receptor and control hyperglycemia. Whether the anti-obesity effect of leflunomide is mediated by targeting S6K1 and its underlying mechanisms remain unclear. Here, we report that A77 1726 induced LC3 lipidation and increased the formation of autophagosomes and lipoautolysosomes in 3T3-L1 adipocytes by activating TGF-ß-activated kinase 1 (TAK1), AMP-activated kinase (AMPK), and Unc-51 like autophagy-activated kinase 1 (ULK1). A77 1726 reduced the content of lipid droplets in 3T3-L1 adipocytes, which was blocked by bafilomycin or by beclin-1 knockdown. Similar observations were made in murine adipocytes differentiated from S6K1-/- embryonic fibroblasts (MEFs). Leflunomide treatment restricted bodyweight gains in ob/ob mice and reduced the visceral fat deposit and the size of adipocytes. Leflunomide treatment induced autophagy in adipose and liver tissues and reduced hepatic lipid contents. Consistently, S6K1 knockout increased the levels of LC3 lipidation in the liver, muscle, and fat of S6K-/- mice. Leflunomide treatment and S6K1 deficiency both induced TAK1, AMPK, and ULK1 phosphorylation in these tissues. These observations collectively suggest that leflunomide controls obesity in part by activating AMPK and inducing lipophagy. Our study provides insights into the mechanisms of leflunomide-mediated anti-obesity activity.


Assuntos
Proteínas Quinases Ativadas por AMP , Autofagia , Camundongos , Humanos , Animais , Leflunomida/farmacologia , Proteínas Quinases Ativadas por AMP/metabolismo , Obesidade/tratamento farmacológico
4.
Am J Bot ; : e16355, 2024 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-38831659

RESUMO

PREMISE: Theories of plant-herbivore interactions hold that seedlings are more vulnerable to herbivory in warmer and more stable climates at lower elevations. Hypotheses of plant apparency, resource concentration, and resource availability have been proposed to explain variability in leaf herbivory. However, seasonal differences in the effects of these hypotheses on leaf herbivory on seedlings remain unclear. METHODS: We evaluated the three herbivory hypotheses by comparing the percentage and frequency of leaf herbivory in understory broadleaf seedlings in a subtropical forest in May (spring) and October (autumn) along an elevational gradient (290-1370 m a.s.l.). In total, we measured 2890 leaves across 696 seedlings belonging to 95 species and used beta regressions to test the effects of plant apparency (e.g., leaf area, seedling height), resource concentration (e.g., plant species diversity), and resource availability (e.g., canopy openness, soil available N and P) on leaf herbivory. RESULTS: Seedlings exhibited unimodal patterns of leaf herbivory along elevation, with drivers of leaf herbivory varying by the month. Variation in the frequency of leaf herbivory was best explained by the resource concentration hypothesis (e.g., plant species diversity) in both months, and herbivory was lower on seedlings in sites with higher plant diversity. Plant apparency hypothesis (e.g., leaf area, seedling height) was weakly supported only in spring, and the evidence for resource availability hypothesis (e.g., canopy openness, soil nutrients) was mixed. CONCLUSIONS: This study supports the resource concentration hypothesis and reveals the importance of seasonal difference on understanding leaf herbivory patterns and the drivers of plant diversity in subtropical forests.

5.
Inorg Chem ; 63(3): 1642-1651, 2024 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-38198689

RESUMO

Advanced energetic materials (EMs) play a crucial role in the advancement of microenergetic systems as actuation parts, igniters, propulsion units, and power. The sustainable electrosynthesis of EMs has gained momentum and achieved substantial improvements in the past decade. This study presents the facile synthesis of a new type of high-performance CuN3@CuCl hybrids via a co-electrodeposition methodology utilizing porous Cu as the sacrificial template. The composition, morphology, and energetic characteristics of the CuN3@CuCl hybrids can be easily tuned by adjusting the deposition times. The resulting hybrids demonstrate remarkable energy output (1120 J·g-1) and good laser-induced initiating ability. As compared with porous CuN3, the uniform doping of inert CuCl enhances the electrostatic safety of the hybridized material without compromising its overall energetic characteristics. Notably, the special oxidizing behavior of CuCl gradually lowers the susceptibility of the hybrid material to laser and electrostatic stimulation. This has significant implications for the passivation or self-destruction of highly sensitive EMs. Overall, this study pioneers a new path for the development of MEMS-compatible EMs, facilitating further microenergetic applications.

6.
Environ Sci Technol ; 58(16): 7020-7031, 2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38608167

RESUMO

Adjusting the electronic state of noble metal catalysts on a nanoscale is crucial for optimizing the performance of nanocatalysts in many important environmental catalytic reactions, particularly in volatile organic compound (VOC) combustion. This study reports a novel strategy for optimizing Pt catalysts by modifying their electronic structure to enhance the electron density of Pt. The research illustrates the optimal 0.2Pt-0.3W/Fe2O3 heterostructure with atomic-thick WO3 layers as a bulking block to electronically modify supported Pt nanoparticles. Methods such as electron microscopy, X-ray photoelectron spectroscopy, and in situ Fourier transform infrared spectroscopy confirm Pt's electron-enriched state resulting from electron transfer from atomic-thick WO3. Testing for benzene oxidation revealed enhanced low-temperature activity with moderate tungsten incorporation. Kinetic and mechanistic analyses provide insights into how the enriched electron density benefits the activation of oxygen and the adsorption of benzene on Pt sites, thereby facilitating the oxidation reaction. This pioneering work on modifying the electronic structure of supported Pt nanocatalysts establishes an innovative catalyst design approach. The electronic structure-performance-dependent relationships presented in this study assist in the rational design of efficient VOC abatement catalysts, contributing to clean energy and environmental solutions.

7.
Exp Cell Res ; 427(1): 113572, 2023 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-36990422

RESUMO

Long non-coding RNAs (lncRNAs) are pivotal regulators in heart disease, including myocardial ischemia/reperfusion (I/R) injury. LncRNA just proximal to XIST (JPX) is a molecular switch for X-chromosome inactivation. Enhancer of zeste homolog 2 (EZH2) is a core catalytic subunit of the polycomb repressive complex 2 (PRC2), which is involved in chromatin compaction and gene repression. This study aims to explore the mechanism of JPX regulating the expression of Sarcoplasmic/endoplasmic reticulum Ca2+ ATPase 2a (SERCA2a) by binding to EZH2 and preventing cardiomyocyte I/R damage in vivo and in vitro. First, we constructed mouse myocardial I/R and HL1 cell hypoxia/reoxygenation models, and found that JPX was low expressed in both models. JPX overexpression alleviated cardiomyocyte apoptosis in vivo and in vitro, reduced the I/R-induced infarct size in mouse hearts, lowered the serum cTnI concentration, and promoted mouse cardiac systolic function. The evidence implies that JPX can alleviate I/R-induced acute cardiac damage. Mechanistically, the FISH and RIP assays showed that JPX could bind to EZH2. The ChIP assay revealed EZH2 enrichment at the promoter region of SERCA2a. Both the EZH2 and H3K27me3 levels at the promoter region of SERCA2a were reduced in the JPX overexpression group compared to those in the Ad-EGFP group (P < 0.01). In summary, our results suggested that LncRNA JPX directly bound to EZH2 and reduced the EZH2-mediated H3K27me3 in the SERCA2a promoter region, protecting the heart from acute myocardial I/R injury. Therefore, JPX might be a potential therapeutic target for I/R injury.


Assuntos
Traumatismo por Reperfusão Miocárdica , RNA Longo não Codificante , Camundongos , Animais , Traumatismo por Reperfusão Miocárdica/genética , Traumatismo por Reperfusão Miocárdica/metabolismo , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Proteína Potenciadora do Homólogo 2 de Zeste/genética , Proteína Potenciadora do Homólogo 2 de Zeste/metabolismo , Histonas/metabolismo , Camundongos Endogâmicos C57BL , Miócitos Cardíacos/metabolismo , Apoptose/genética
8.
Lipids Health Dis ; 23(1): 203, 2024 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-38937793

RESUMO

BACKGROUND: Triglyceride glucose (TyG) index combined with obesity-related indicators [triglyceride glucose-body mass index (TyG-BMI), triglyceride glucose-waist to height ratio (TyG-WHtR), triglyceride glucose-waist circumference (TyG-WC)], represents emerging methodologies for assessing insulin resistance. The objective of this investigation was to explore the correlation between TyG-related indices and gallstone disease. METHODS: The study included 3740 adults from the 2017-2020 period of the National Health and Nutrition Examination Survey. TyG-BMI, TyG-WC, and TyG-WHtR were integrated as both continuous and categorical variables within the multivariate logistic model, respectively to evaluate the connection between various TyG-related indices and gallstone disease. Additionally, restriction cubic splines and subgroup analysis were employed to deepen our understanding of this relationship. RESULTS: When analyzed as continuous variables, positive correlations were observed between TyG-BMI, TyG-WC, TyG-WHtR and gallstone disease. The OR(95%CI) were 1.063(1.045,1.082) for TyG-BMI (per 10-unit), 1.026(1.018,1.034) for TyG-WC (per 10-unit) and 1.483(1.314,1.676) for TyG-WHtR (per 1-unit), respectively. When categorized into quartiles, these three TyG-related indices still show statistically significant associations with gallstone disease. Descending in order, the diagnostic capability for gallstone disease is demonstrated as follows: TyG-WHtR (AUC = 0.667), TyG-BMI (AUC = 0.647), and TyG-WC (AUC = 0.640). CONCLUSION: There were significantly positive associations between TyG-related indices, including TyG-BMI, TyG-WC, and TyG-WHtR, and gallstone disease. Of these indices, TyG-WHtR demonstrated the most favorable performance in identifying the risk of gallstone disease.


Assuntos
Glicemia , Índice de Massa Corporal , Cálculos Biliares , Inquéritos Nutricionais , Triglicerídeos , Humanos , Triglicerídeos/sangue , Feminino , Cálculos Biliares/sangue , Cálculos Biliares/epidemiologia , Masculino , Pessoa de Meia-Idade , Adulto , Glicemia/metabolismo , Circunferência da Cintura , Fatores de Risco , Resistência à Insulina , Estados Unidos/epidemiologia , Obesidade/sangue , Obesidade/epidemiologia , Idoso
9.
Matern Child Health J ; 28(5): 926-934, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38182833

RESUMO

OBJECTIVES: Parental involvement can affect child school readiness, which in turn influences subsequent child learning outcomes. While social support, stress, caregiver psychological distress, and drinking could affect parental involvement, it is unknown whether and how these factors influence downstream child learning outcomes through parental involvement and child school readiness. This study tests those associations. METHODS: Using de-identified data provided by the Alaska Longitudinal Child Abuse and Neglect Linkage project (N = 683), we use Structural Equation Modeling to assess direct and indirect effects of paths embedded in the proposed model. RESULTS: This study found statistically significant indirect effects: (1) path linking stress faced by caregivers to child reading proficiency through caregiver psychological distress, parental involvement, and child school readiness, (2) path linking stress faced by caregivers to child reading proficiency through caregiver drinking, parental involvement, and child school readiness, and (3) path linking social support for caregivers to child reading proficiency through caregiver psychological distress, parental involvement, and child school readiness. Post-estimation showed that the sum of the magnitude of total effects of stress and the magnitude of total effects of support is significantly larger than either alone. CONCLUSIONS FOR PRACTICE: Findings suggest that reducing caregiver stress and offering social support could not only benefit caregivers but learning outcomes of their children as well. For child learning outcomes, simultaneously reducing stress and offering social support for caregivers, rather than just one of them alone, is suggested. These results are important for children, particularly for those raised by caregivers experiencing psychological distress or drinking issues.


Assuntos
Pais , Estresse Psicológico , Criança , Humanos , Fatores de Proteção , Alaska , Estresse Psicológico/psicologia , Pais/psicologia , Instituições Acadêmicas , Cuidadores/psicologia
10.
Int J Mol Sci ; 25(8)2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38673762

RESUMO

The WRKY gene family is crucial for regulating plant growth and development. However, the WRKY gene is rarely studied in naked kernel formation in hull-less Cucurbita pepo L. (HLCP), a natural mutant that lacks the seed coat. In this research, 76 WRKY genes were identified through bioinformatics-based methods in C. pepo, and their phylogenetics, conserved motifs, synteny, collinearity, and temporal expression during seed coat development were analyzed. The results showed that 76 CpWRKYs were identified and categorized into three main groups (I-III), with Group II further divided into five subgroups (IIa-IIe). Moreover, 31 segmental duplication events were identified in 49 CpWRKY genes. A synteny analysis revealed that C. pepo shared more collinear regions with cucumber than with melon. Furthermore, quantitative RT-PCR (qRT-PCR) results indicated the differential expression of CpWRKYs across different varieties, with notable variations in seed coat development between HLCP and CP being attributed to differences in CpWRKY5 expression. To investigate this further, CpWRKY5-overexpression tobacco plants were generated, resulting in increased lignin content and an upregulation of related genes, as confirmed by qRT-PCR. This study offers valuable insights for future functional investigations of CpWRKY genes and presents novel information for understanding the regulation mechanism of lignin synthesis.


Assuntos
Cucurbita , Regulação da Expressão Gênica de Plantas , Família Multigênica , Proteínas de Plantas , Fatores de Transcrição , Cucurbita/genética , Cucurbita/crescimento & desenvolvimento , Genoma de Planta , Lignina/metabolismo , Lignina/biossíntese , Nicotiana/genética , Nicotiana/metabolismo , Filogenia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Sementes/genética , Sementes/crescimento & desenvolvimento , Sintenia , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
11.
Int Heart J ; 65(2): 292-299, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38556337

RESUMO

B-type natriuretic peptide (BNP) possesses protective cardiovascular properties; however, there has not been sufficient serious consideration of the side effects of BNP. As for sarcoplasmic/endoplasmic reticulum calcium ATPase 2a (SERCA2a), it was once considered a new target for the treatment of heart failure (HF). Nevertheless, clinical trials of SERCA2a gene therapy in HF have finally become unsuccessful. Research has found that elevated BNP levels and decreased SERCA2a expression are two important HF characteristics, which are always negatively correlated. We hypothesize that BNP inhibits SERCA2a expression and, therefore, exerts negative effects on SERCA2a expression and function.The effects of BNP on endogenous SERCA2a expression and function were tested in mice with HF induced by transverse aortic constriction and neonatal rat cardiomyocytes (NRCM). Furthermore, to verify the effects of BNP on exogenous SERCA2a gene transduction efficacy, BNP was added to the myocardium and cardiomyocytes infected with an adenovirus overexpressing SERCA2a.In vivo, BNP levels were increased, SERCA2a expression was reduced in both the BNP intervention and HF groups, and BNP reduced the overexpressed exogenous SERCA2a protein in the myocardium. Our in vitro data showed that BNP dose-dependently inhibited the total and exogenous SERCA2a expression in NRCM by activating the cGMP-dependent protein kinase G. BNP also inhibited the effects of SERCA2a overexpression on Ca2+ transience in NRCM.The expression and function of endogenous and exogenous SERCA2a are inhibited by BNP. The opposite relationship between BNP and SERCA2a should be given serious attention in the treatment of HF via BNP or SERCA2a gene therapy.


Assuntos
Insuficiência Cardíaca , ATPases Transportadoras de Cálcio do Retículo Sarcoplasmático , Ratos , Camundongos , Animais , ATPases Transportadoras de Cálcio do Retículo Sarcoplasmático/genética , ATPases Transportadoras de Cálcio do Retículo Sarcoplasmático/metabolismo , Peptídeo Natriurético Encefálico/metabolismo , Miocárdio/metabolismo , Miócitos Cardíacos/metabolismo
12.
Int J Cancer ; 153(11): 1894-1903, 2023 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-37409565

RESUMO

Neoadjuvant programmed cell death protein 1 (PD-1) blockade exhibits promising efficacy in patients with mismatch repair deficient (dMMR) colorectal cancer (CRC). However, discrepancies between radiological and histological findings have been reported in the PICC phase II trial (NCT03926338). Therefore, we strived to discern radiological features associated with pathological complete response (pCR) based on computed tomography (CT) images. Data were obtained from the PICC trial that included 36 tumors from 34 locally advanced dMMR CRC patients, who received neoadjuvant PD-1 blockade for 3 months. Among the 36 tumors, 28 (77.8%) tumors achieved pCR. There were no statistically significant differences in tumor longitudinal diameter, the percentage change in tumor longitudinal diameter from baseline, primary tumor sidedness, clinical stage, extramural venous invasion status, intratumoral calcification, peritumoral fat infiltration, intestinal fistula and tumor necrosis between the pCR and non-pCR tumors. Otherwise, tumors with pCR had smaller posttreatment tumor maximum thickness (median: 10 mm vs 13 mm, P = .004) and higher percentage decrease in tumor maximum thickness from baseline (52.9% vs 21.6%, P = .005) compared to non-pCR tumors. Additionally, a higher proportion of the absence of vascular sign (P = .003, odds ratio [OR] = 25.870 [95% CI, 1.357-493.110]), nodular sign (P < .001, OR = 189.000 [95% CI, 10.464-3413.803]) and extramural enhancement sign (P = .003, OR = 21.667 [2.848-164.830]) was observed in tumors with pCR. In conclusion, these CT-defined radiological features may have the potential to serve as valuable tools for clinicians in identifying patients who have achieved pCR after neoadjuvant PD-1 blockade, particularly in individuals who are willing to adopt a watch-and-wait strategy.


Assuntos
Neoplasias do Colo , Neoplasias Colorretais , Inibidores de Checkpoint Imunológico , Humanos , Neoplasias do Colo/patologia , Neoplasias Colorretais/diagnóstico por imagem , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/genética , Reparo de Erro de Pareamento de DNA , Terapia Neoadjuvante/métodos , Receptor de Morte Celular Programada 1 , Inibidores de Checkpoint Imunológico/uso terapêutico
13.
J Transl Med ; 21(1): 214, 2023 03 22.
Artigo em Inglês | MEDLINE | ID: mdl-36949511

RESUMO

BACKGROUND: Stratification of DNA mismatch repair (MMR) status in patients with colorectal cancer (CRC) enables individual clinical treatment decision making. The present study aimed to develop and validate a deep learning (DL) model based on the pre-treatment CT images for predicting MMR status in CRC. METHODS: 1812 eligible participants (training cohort: n = 1124; internal validation cohort: n = 482; external validation cohort: n = 206) with CRC were enrolled from two institutions. All pretherapeutic CT images from three dimensions were trained by the ResNet101, then integrated by Gaussian process regression (GPR) to develop a full-automatic DL model for MMR status prediction. The predictive performance of the DL model was evaluated using the area under the receiver operating characteristic curve (AUC) and then tested in the internal and external validation cohorts. Additionally, the participants from institution 1 were sub-grouped by various clinical factors for subgroup analysis, then the predictive performance of the DL model for identifying MMR status between participants in different groups were compared. RESULTS: The full-automatic DL model was established in the training cohort to stratify the MMR status, which presented promising discriminative ability with the AUCs of 0.986 (95% CI 0.971-1.000) in the internal validation cohort and 0.915 (95% CI 0.870-0.960) in the external validation cohort. In addition, the subgroup analysis based on the thickness of CT images, clinical T and N stages, gender, the longest diameter, and the location of tumors revealed that the DL model showed similar satisfying prediction performance. CONCLUSIONS: The DL model may potentially serve as a noninvasive tool to facilitate the pre-treatment individualized prediction of MMR status in patients with CRC, which could promote the personalized clinical-making decision.


Assuntos
Neoplasias do Colo , Neoplasias Colorretais , Aprendizado Profundo , Humanos , Neoplasias Colorretais/diagnóstico por imagem , Neoplasias Colorretais/genética , Neoplasias Colorretais/tratamento farmacológico , Reparo de Erro de Pareamento de DNA , Tomografia Computadorizada por Raios X/métodos , Estudos Retrospectivos
14.
Philos Trans A Math Phys Eng Sci ; 381(2259): 20220333, 2023 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-37691465

RESUMO

The presence of short-chain per- and polyfluoroalkyl substances in water poses a major health and environmental challenge. Here, we have performed high-energy small- and wide-angle X-ray scattering measurements on CF3[CF2]nCOOH (where n = 1, 2, 3 represents the chain length) and their aqueous solutions at 10% mole concentrations to characterize their molecular interactions at the atomic and nanometer length scales. The experimental wide-angle structure factors have been modelled using Empirical Potential Structural Refinement. The oxygen-oxygen partial X-ray pair distribution functions show that the coordination number between the hydroxyl oxygen on the acid and surrounding oxygen water molecules increases significantly with acid chain length, rising from 3.2 for n = 1 to 4.1 for n = 3. The small-angle scattering is dominated by a sharp, high-intensity peak at Q1 ∼ 0.2 Å-1 and a smaller peak at Q2 = 1.2 Å-1 for n = 3, both of which decrease with decreasing chain length. The Q2 peak is attributed to groups of adjacent non-bonded acid molecules, and Q1 has contributions from both correlations between acid molecules and water-water interactions. In all cases, the models show nanoscale aggregation occurs in the form of denser channels of winding hydrogen-bonded chains, approximately 20 water molecules in length, surrounding clusters of acid molecules. This article is part of the theme issue 'Exploring the length scales, timescales and chemistry of challenging materials (Part 2)'.

15.
BMC Vet Res ; 19(1): 187, 2023 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-37789311

RESUMO

BACKGROUND: Avian Escherichia coli (E.coli) type 1 fimbriae adhere to avian tracheal epithelial cells through the FimH protein. However, the adhesion-related antigen is still unknown. The purpose of this study was to analyze the antigenicity of the type 1 fimbrial FimH protein of wild-type avian E. coli, screen antigen epitopes, and prepare monoclonal antibodies (mAbs) that can block the adhesion of avian E. coli. RESULTS: In this study, the nucleic acid homologies of MG2 (O11), TS12 (O18), and YR5 (O78) with K12 were 97.7%, 99.6%, and 97.7%, respectively, and the amino acid sequence similarity reached 98.7%, 99.3%, and 98.0%, respectively. The epitopes and hydrophilicities of the FimH proteins of these three strains were similar. The more obvious lectin domain epitopes were located at FimH protein positions 111-124 and 154-162. The mAbs 7C2 and 7D8 against these two epitopes were prepared. An adhesion inhibition test showed that 7C2 and 7D8 blocked bacterial adhesion to avian tracheal epithelial cells. The mAb 7C2 against the 111-124 epitope inhibited O78 strain adhesion by 93%, and the mAb 7D8 against the 154-162 epitope inhibited O78 strain adhesion by 49%, indicating that these two epitopes are closely related to the adhesion of type 1 fimbriae. However, only the 111-124 epitope-recognizing mAb 7C2 inhibited bacterial agglutination of erythrocytes, indicating that host cell receptor binding and erythrocyte agglutination are not mediated by the same spatial locations within the FimH protein. CONCLUSIONS: The results demonstrate that the mAbs 7C2 and 7D8 against FimH protein positions 111-124 and 154-162 could inhibit the adhesion of E.coli to the chicken trachea.


Assuntos
Escherichia coli , Proteínas de Fímbrias , Animais , Escherichia coli/genética , Proteínas de Fímbrias/genética , Epitopos/metabolismo , Adesinas de Escherichia coli/genética , Adesinas de Escherichia coli/química , Aglutininas/metabolismo , Aderência Bacteriana
16.
Heart Vessels ; 38(1): 40-48, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35915265

RESUMO

This study was designed to assess coronary microvascular obstruction (MVO) in patients with acute ST-segment elevation myocardial infarction (STEMI) by cardiac magnetic resonance T2-weighted short tau inversion recovery (T2-STIR) image and layer-specific analysis of 2-dimensional speckle tracking echocardiography combined with low-dose dobutamine stress echocardiography (LDDSE-LS2D-STE). 32 patients were enrolled to perform cardiac magnetic resonance and echocardiography 5-7 days after primary percutaneous coronary intervention. Infarcted myocardium was categorized into MVO+ group and MVO- group by late gadolinium enhancement as gold standard. At T2-weighted image, the area of hyper-intense region and hypo-intense core inside were marked as A1, A2 and A2/A1 > 0 represented MVO. Strain parameters were composed of longitudinal strain (LS), circumferential strain and radial strain at rest and dobutamine stress. There were 94 MVO+ segments, 136 MVO- segments according to gold standard. 96 segments had hypo-intense core at T2-STIR image. The sensitivity and specificity of T2-STIR in detecting MVO were 91.49 and 92.65%. Endocardial LS was superior to other parameters, and stress endocardial LS was higher than that of resting endocardial LS (sensitivity: 77.11% vs 72.29%, specificity: 93.28% vs 83.19%, AUC: 0.87 vs 0.82, P < 0.05). The combination of T2-STIR and stress endocardial LS in parallel test could improve sensitivity significantly (98.05% vs 91.49%). T2-STIR has higher diagnostic value in detecting MVO with some limitations. However, LDDSE-LS2D-STE with cost-effective and handling may be a good alternative to T2-STIR. It provides additional and reliable diagnostic tools to identify MVO in STEMI patients after reperfusion.


Assuntos
Oclusão Coronária , Infarto do Miocárdio , Intervenção Coronária Percutânea , Infarto do Miocárdio com Supradesnível do Segmento ST , Humanos , Infarto do Miocárdio com Supradesnível do Segmento ST/diagnóstico , Infarto do Miocárdio com Supradesnível do Segmento ST/terapia , Ecocardiografia sob Estresse , Infarto do Miocárdio/patologia , Meios de Contraste , Gadolínio , Ecocardiografia/métodos , Espectroscopia de Ressonância Magnética , Imagem Cinética por Ressonância Magnética
17.
Chem Soc Rev ; 51(6): 1899-1925, 2022 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-35246673

RESUMO

Machine learning (ML) is becoming an effective tool for studying 2D materials. Taking as input computed or experimental materials data, ML algorithms predict the structural, electronic, mechanical, and chemical properties of 2D materials that have yet to be discovered. Such predictions expand investigations on how to synthesize 2D materials and use them in various applications, as well as greatly reduce the time and cost to discover and understand 2D materials. This tutorial review focuses on the understanding, discovery, and synthesis of 2D materials enabled by or benefiting from various ML techniques. We introduce the most recent efforts to adopt ML in various fields of study regarding 2D materials and provide an outlook for future research opportunities. The adoption of ML is anticipated to accelerate and transform the study of 2D materials and their heterostructures.


Assuntos
Eletrônica , Aprendizado de Máquina , Algoritmos
18.
Medicina (Kaunas) ; 59(2)2023 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-36837499

RESUMO

Background and Objectives: Metformin has been found to potentially reduce the risk and improve the prognosis of a variety of tumors, but these findings remain controversial in biliary tract cancer (BTC). Therefore, this systematic review and meta-analysis was conducted to investigate the association between metformin and BTC. Materials and Methods: Two independent researchers comprehensively searched PubMed, Embase, the Cochrane Library, and Web of Science for eligible studies published from their inception to 31 March 2022. Comparisons of risk, overall survival (OS), and disease-free survival (DFS) for patients with BTC were selected as the endpoints of interest and pooled by random or fixed-effects models. Results: Eleven studies with a total of 24,788,738 participants were eligible for this analysis. The overall pooled effects showed no significant differences in biliary tract cancer risk (hazard ratio (HR) = 0.82, 95% confidence interval (CI): 0.50-1.35, p = 0.436), OS (HR = 0.88, 95% CI: 0.74-1.04, p = 0.135), or DFS (HR = 1.03, 95% CI: 0.79-1.34, p = 0.829) between metformin users and non-users. When restricting participants to those with diabetes, a similar negative result was found, demonstrating that metformin use was not significantly associated with a lower risk of developing BTC compared with a lack of metformin use (HR = 0.65, 95% CI: 0.39-1.07, p = 0.089); notably, the included studies exhibited significant heterogeneity in the selection of participants and the definition of metformin users. Conclusions: Metformin may not be able to reduce the risk of BTC and improve prognosis in certain populations. Based on the limited quantity and quality of the included studies, the present results should be interpreted within their limitations, and further studies are warranted to determine the optimal timing, dose, duration, and scenario of metformin administration.


Assuntos
Neoplasias do Sistema Biliar , Diabetes Mellitus , Metformina , Humanos , Hipoglicemiantes , Prognóstico , Neoplasias do Sistema Biliar/patologia
19.
J Cell Physiol ; 237(1): 373-388, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34676546

RESUMO

Circular RNAs (circRNAs) are closed back-splicing products of precursor mRNA in eukaryotes. Compared with linear mRNAs, circRNAs have a special structure and stable expression. A large number of studies have provided different regulatory mechanisms of circRNAs in tumors. Challenges exist in understanding the control of circRNAs because of their sequence overlap with linear mRNA. Here, we survey the most recent progress regarding the regulation of circRNA biogenesis by RNA-binding proteins, one of the vital functional proteins. Furthermore, substantial circRNAs exert compelling biological roles by acting as protein sponges, by being translated themselves or regulating posttranslational modifications of proteins. This review will help further explore more types of functional proteins that interact with circRNA in cancer and reveal other unknown mechanisms of circRNA regulation.


Assuntos
Neoplasias , RNA Circular , Humanos , Neoplasias/genética , RNA/genética , Precursores de RNA/metabolismo , RNA Circular/genética , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Proteínas de Ligação a RNA/genética , Proteínas de Ligação a RNA/metabolismo
20.
Emerg Infect Dis ; 28(8): 1703-1707, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35820171

RESUMO

Although reports of human infection with influenza A(H5N6) increased in 2021, reports of similar H5N6 virus infection in poultry are few. We detected 10 avian influenza A(H5N6) clade 2.3.4.4b viruses in poultry from 4 provinces in China. The viruses showed strong immune-escape capacity and complex genetic reassortment, suggesting further transmission risk.


Assuntos
Vírus da Influenza A , Influenza Aviária , Influenza Humana , Animais , Aves , China/epidemiologia , Humanos , Vírus da Influenza A/genética , Influenza Aviária/epidemiologia , Influenza Humana/epidemiologia , Filogenia , Aves Domésticas , Vírus Reordenados/genética
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