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Adipose tissue remodeling and plasticity are dynamically regulated by the coordinated functions of adipocytes, macrophages, and endothelial cells and extracellular matrix (ECM) that provides stiffness networks in adipose tissue component cells. Inflammation and fibrosis are crucial exogenous factors that dysregulate adipose tissue functions and drastically change the mechanical properties of the ECM. Therefore, communication among the ECM and adipose tissue component cells is necessary to understand the multifaceted functions of adipose tissues. To obtain in vivo stiffness, we used genipin as a crosslinker for collagen gels. Meanwhile, we isolated primary adipocytes, macrophages, and endothelial cells from C57BL/6J mice and incubated these cells in the differentiation media on temperature-responsive culture dishes. After the differentiation, these cell sheets were transferred onto genipin-crosslinked collagen gels with varying matrix stiffness. We found that inflammatory gene expressions were induced by hard matrix, whereas antiinflammatory gene expressions were promoted by soft matrix in all three types of cells. Interestingly, the coculture experiments of adipocytes, macrophages, and endothelial cells showed that the effects of soft or hard matrix stiffness stimulation on adipocytes were transmitted to the distant adipose tissue component cells, altering their gene expression profiles under normal matrix conditions. Finally, we identified that a hard matrix induces the secretion of CXCL13 from adipocytes, and CXCL13 is one of the important transmitters for stiffness communication with macrophages and endothelial cells. These findings provide insight into the mechanotransmission into distant cells and the application of stiffness control for chronic inflammation in adipose tissues with metabolic dysregulation.
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Lactate serves as the major glucose alternative to an energy substrate in the brain. Lactate level is increased in the fetal brain from the middle stage of gestation, indicating the involvement of lactate in brain development and neuronal differentiation. Recent reports show that lactate functions as a signaling molecule to regulate gene expression and protein stability. However, the roles of lactate signaling in neuronal cells remain unknown. Here, we showed that lactate promotes the all stages of neuronal differentiation of SH-SY5Y and Neuro2A, human and mouse neuroblastoma cell lines, characterized by increased neuronal marker expression and the rates of neurites extension. Transcriptomics revealed many lactate-responsive genes sets such as SPARCL1 in SH-SY5Y, Neuro2A, and primary embryonic mouse neuronal cells. The effects of lactate on neuronal function were mainly mediated through monocarboxylate transporters 1 (MCT1). We found that NDRG family member 3 (NDRG3), a lactate-binding protein, was highly expressed and stabilized by lactate treatment during neuronal differentiation. Combinative RNA-seq of SH-SY5Y with lactate treatment and NDRG3 knockdown shows that the promotive effects of lactate on neural differentiation are regulated through NDRG3-dependent and independent manners. Moreover, we identified TEA domain family member 1 (TEAD1) and ETS-related transcription factor 4 (ELF4) are the specific transcription factors that are regulated by both lactate and NDRG3 in neuronal differentiation. TEAD1 and ELF4 differently affect the expression of neuronal marker genes in SH-SY5Y cells. These results highlight the biological roles of extracellular and intracellular lactate as a critical signaling molecule that modifies neuronal differentiation.
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Diferenciação Celular , Regulação da Expressão Gênica , Peptídeos e Proteínas de Sinalização Intracelular , Ácido Láctico , Neurônios , Animais , Humanos , Camundongos , Diferenciação Celular/fisiologia , Linhagem Celular , Regulação da Expressão Gênica/genética , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Ácido Láctico/metabolismo , Ácido Láctico/farmacologia , Neuroblastoma/genética , Neurônios/citologia , Neurônios/metabolismo , Transdução de SinaisRESUMO
Photoionization is one of the most fundamental processes in light-matter interaction. Advanced attosecond photoelectron spectroscopy provides the possibility to characterize the ultrafast photoemission process in an extremely short attosecond time scale. Following scattering symmetry rules, residual ions encode ultrafast photoionization prints at the instant of electron removal forming an alternative electron emission chronoscope. Here, we experimentally illustrate the attosecond ion reconstruction of attosecond beating by interference of two-photon transition (RABBIT)-like interferometry through the development of high-resolution ion momentum detection in atomic photoionization processes. Our ion interferometry presents identical momentum- and time-dependent scattering phase shift, as we observed in photoelectron spectroscopy, and thus demonstrates that ion interferometry can be a possible alternative attosecond approach to resolve the photoionization process, without the electron homogeneity limitation.
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Hydrogel-based flexible electronic devices serve as a next-generation bridge for human-machine interaction and find extensive applications in clinical therapy, military equipment, and wearable devices. However, the mechanical mismatch between hydrogels and human tissues, coupled with the failure of conformal interfaces, hinders the transmission of information between living organisms and flexible devices, which resulted in the instability and low fidelity of signals, especially in the acquisition of electromyographic (EMG) and electrocardiographic (ECG) signals. In this study, we designed an ion-conductive hydrogel (ICHgel) utilizing multiple physical interactions, successfully applied for human motion monitoring and the collection of epidermal physiological signals. By incorporating fumed silica (F-SiO2) nanoparticles and calcium chloride into an interpenetrating network (IPN) composed of polyvinyl alcohol (PVA) and polyacrylamide (AAm)/acrylic acid (AA) chains, the ICHgel exhibited exceptional tunable stretchability (>1450% strain) and conductivity (10.58 ± 0.85 S m-1). Additionally, the outstanding adhesion of the ICHgel proved to be a critical factor for effective communication between epidermal tissues and flexible devices. Demonstrating its capability to acquire stable electromechanical signals, the ICHgel was attached to different parts of the human body. More importantly, as a flexible electrode, the ICHgel outperformed commercial Ag/AgCl electrodes in the collection of ECG and EMG signals. In summary, the synthesized ICHgel with its outstanding conformal interface capabilities and mechanical adaptability paves the way for enhanced human-machine interaction, fostering the development of flexible electronic devices.
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Acrilatos , Condutividade Elétrica , Hidrogéis , Humanos , Hidrogéis/química , Dispositivos Eletrônicos Vestíveis , Resinas Acrílicas/química , Álcool de Polivinil/química , Eletromiografia , Eletrocardiografia , Adesivos/química , Dióxido de Silício/química , EletrodosRESUMO
PURPOSE: The previous studies that examined the effectiveness of unsupervised machine learning methods versus traditional methods in assessing dietary patterns and their association with incident hypertension showed contradictory results. Consequently, our aim is to explore the correlation between the incidence of hypertension and overall dietary patterns that were extracted using unsupervised machine learning techniques. METHODS: Data were obtained from Japanese male participants enrolled in a prospective cohort study between August 2008 and August 2010. A final dataset of 447 male participants was used for analysis. Dimension reduction using uniform manifold approximation and projection (UMAP) and subsequent K-means clustering was used to derive dietary patterns. In addition, multivariable logistic regression was used to evaluate the association between dietary patterns and the incidence of hypertension. RESULTS: We identified four dietary patterns: 'Low-protein/fiber High-sugar,' 'Dairy/vegetable-based,' 'Meat-based,' and 'Seafood and Alcohol.' Compared with 'Seafood and Alcohol' as a reference, the protective dietary patterns for hypertension were 'Dairy/vegetable-based' (OR 0.39, 95% CI 0.19-0.80, P = 0.013) and the 'Meat-based' (OR 0.37, 95% CI 0.16-0.86, P = 0.022) after adjusting for potential confounding factors, including age, body mass index, smoking, education, physical activity, dyslipidemia, and diabetes. An age-matched sensitivity analysis confirmed this finding. CONCLUSION: This study finds that relative to the 'Seafood and Alcohol' pattern, the 'Dairy/vegetable-based' and 'Meat-based' dietary patterns are associated with a lower risk of hypertension among men.
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Dieta , Hipertensão , Aprendizado de Máquina , Humanos , Masculino , Hipertensão/epidemiologia , Japão/epidemiologia , Incidência , Pessoa de Meia-Idade , Estudos Prospectivos , Dieta/métodos , Dieta/estatística & dados numéricos , Estudos de Coortes , Adulto , Fatores de Risco , Comportamento Alimentar , Padrões Dietéticos , População do Leste AsiáticoRESUMO
BACKGROUND: Spinocerebellar ataxia 2 (SCA2) with a low range of CAG repeat expansion of ATXN2 gene can present with predominant or isolated parkinsonism that closely resembles Parkinson's disease (PD). This study is aimed at comparing clinical features, disease progression, and nuclear imaging between ATXN2-related parkinsonism (ATXN2-P) and PD. METHODS: Three hundred and seventy-seven clinically diagnosed PD with family history were screened by multiplex ligation-dependent probe amplification, whole-exome sequencing or target sequencing, and dynamic mutation testing of 10 SCA subtypes. The baseline and longitudinal clinical features as well as the dual-tracer positron emission tomography (PET) imaging were compared between ATXN2-P and genetically undefined familial PD (GU-fPD). RESULTS: Fifteen ATXN2-P patients from 7 families and 50 randomly selected GU-fPD patients were evaluated. Significantly less resting tremor and more symmetric signs were observed in ATXN2-P than GU-fPD. No significant difference was found in motor progression and duration from onset to occurrence of fluctuation, dyskinesia, and recurrent falls between the two groups. Cognitive impairment and rapid-eye-movement sleep behavior disorder were more common in ATXN2-P. During follow-up, olfaction was relatively spared, and no obvious progression of cognition dysfunction evaluated by Mini-Mental State Examination scores was found in ATXN2-P. PET results of ATXN2-P demonstrated a symmetric, diffuse, and homogenous dopamine transporter loss of bilateral striatum and a glucose metabolism pattern inconsistent with that in PD. CONCLUSIONS: Symmetric motor signs and unique nuclear imaging might be the clues to distinguish ATXN2-P from GU-fPD.
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Ataxina-2 , Progressão da Doença , Transtornos Parkinsonianos , Tomografia por Emissão de Pósitrons , Humanos , Masculino , Feminino , Ataxina-2/genética , Pessoa de Meia-Idade , Estudos Longitudinais , Transtornos Parkinsonianos/genética , Transtornos Parkinsonianos/diagnóstico por imagem , Adulto , Idoso , Ataxias Espinocerebelares/diagnóstico por imagem , Ataxias Espinocerebelares/genética , Estudos de CoortesRESUMO
BACKGROUND AND OBJECTIVE: Fractional radiofrequency microneedling (FRM) is widely used as an option for skin rejuvenation, however there is a lack of histological evidence for the various energy delivery systems available. The objective was to assess thermal denaturation of tissue and the wound healing response in monopolar mode versus bipolar mode. Histological analysis was performed to demonstrate the efficacy of automatic impedance feedback system in monopolar mode. STUDY DESIGN AND METHODS: In this study, the acute thermal effects caused by monopolar FRM treatment to the dorsal skin of pigs were assessed histologically by hematoxylin & eosin (H&E) staining. Then, one session of either monopolar or bipolar FRM was used to treat one or the other side of the pig using varying power levels and pulse widths. The acute and chronic tissue reactions were assessed using H&E, immunofluorescence, and western blot analysis at 0, 14, 30, and 90 days after treatment. The efficacy of the impedance feedback system was also monitored histologically. RESULTS: High-energy FRM treatment produced tissue loss and necrosis. The power level and pulse duration significantly affected the coagulation amount. Histopathology at 0, 14, 30, and 90 days showed that the skin tissue reaction was more pronounced for bipolar compared to monopolar FRM. Immunofluorescence showed the expression of TGF-ß, Ki67, MMP3, and elastin increased dramatically with both modes, but were higher in the bipolar FRM treated side. The automatic impedance feedback system could effectively adjust the output energy. CONCLUSIONS: We found that bipolar FRM produced greater thermal effects, more collagen coagulation, and more pronounced molecular changes compared with monopolar mode in a porcine animal model.
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Indução Percutânea de Colágeno , Ondas de Rádio , Suínos , Animais , Necrose , Colágeno , CicatrizaçãoRESUMO
OBJECTIVE: To investigate the predictive ability of global longitudinal strain (GLS) and mechanical dispersion for coronary stenosis and provide a more reliable noninvasive method for diagnosis of obstructive coronary artery disease(OCAD). METHODS: Sixty-seven patients diagnosed with suspected CAD were included in the study. Patients with coronary stenosis greater than 50% were assigned as OCAD, while the others were assigned as non obstructive coronary artery disease(NOCAD). General information was collected and patients underwent speckle tracking echocardiogram(STE). RESULTS: Spearman's correlation analysis showed that GLS and mechanical dispersion were positively correlated with the degree of coronary stenosis (r = 0.383, 0.342, p < 0.05), and there was also a positive correlation between GLS and mechanical dispersion (r = 0.327, p < 0.05). GLS, longitudinal strain (LS) of each chamber, and mechanical dispersion were higher in the OCAD group than in the NOCAD group (p < 0.05). Univariate regression analysis showed that GLS, each lumen LS and mechanical dispersion were statistically significant (p < 0.05). Multifactorial regression analysis showed that elevated GLS (p = 0.007) and elevated mechanical dispersion (p = 0.030) were independent risk factors for OCAD. The ROC curves showed that GLS predicted OCAD (AUC area 0.745, 95% CI 0.624 to 0.865) versus mechanical discrete prediction of OCAD (AUC area 0.702, 95% CI 0.569 to 0.834) were more diagnostic than conventional cardiac ultrasound observations of ventricular wall motion abnormalities (AUC area 0.566, 95% CI 0.463 to 0.669). CONCLUSIONS: Combining GLS with mechanical dispersion can rapidly assess OCAD in a very short period, which has strong promotion value and in-depth research value.
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Doença da Artéria Coronariana , Estenose Coronária , Humanos , Doença da Artéria Coronariana/complicações , Doença da Artéria Coronariana/diagnóstico por imagem , Ecocardiografia/métodos , Coração , Curva ROC , Função Ventricular Esquerda , Reprodutibilidade dos Testes , Valor Preditivo dos TestesRESUMO
BACKGROUND: Blood perfusion in the recipient site is important for adipose tissue repair after fat grafting. It delivers host-derived macrophages derived from monocytes in bone marrow to initiate inflammatory reactions and regenerative responses. According to the ability of CXCL12, a stromal cell-derived factor, to recruit monocytes/macrophages, we studied its effect on adipose tissue repair and regeneration under ischemic and normal conditions. METHODS: Each inguinal fat pad was crushed for 30 seconds with a clamp in mice (n = 35). The left inguinal vessels were divided and cut off (ischemic group), while the right inguinal vessels were kept patent (control group). Seven animals were sacrificed at 1, 3, 7, 14, and 30 days after surgery, and macrophages (Mac2 and CD206) and adipocytes (perilipin) were assessed. Levels of inflammatory factors (interleukin (IL)-1ß, IL-6, and tumor necrosis factor-α) and CXCL12 were measured by quantitative PCR. RESULTS: The number of macrophages was higher in the control group than in the ischemic group at day 3 (10.33 ± 2.40 vs. 1.33 ± 0.33, p = 0.021). The percentage of M2 macrophages was higher in the control group than in the ischemic group at day 7 (p<0.05). The levels of inflammatory factors and CXCL12 were higher in the control group than in the ischemic group at the early stage (p = 0.038). CONCLUSIONS: Established blood perfusion leads to up-regulation of CXCL12 during adipose tissue repair and regeneration, which may increase recruitment of monocytes to damaged adipose tissue. These findings increase understanding of the cellular events involved in fat graft survival after grafting. NO LEVEL ASSIGNED: This journal requires that authors assign a level of evidence to each submission to which Evidence-Based Medicine rankings are applicable. This excludes Review Articles, Book Reviews, and manuscripts that concern Basic Science, Animal Studies, Cadaver Studies, and Experimental Studies. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266.
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BACKGROUND: In plastic surgery tissue transplantation, tissue ischemia limits transplanted tissue survival. Adipose-derived stem cells (ASCs) and stromal vascular fraction (SVF) show potential for promoting angiogenesis and rescuing ischemic conditions. However, when SVF and ASC suspensions are utilized without the protection of extracellular matrix, the retention rate of transplanted cells tends to be diminished, leading to an unsatisfactory therapeutic outcome. To overcome this, adipose tissue-derived microvascular fragments (ad-MVFs) have emerged as a promising solution. METHODS: We conducted enzymatic digestion on human adipose tissue to generate ad-MVFs. These fragments underwent a thorough characterization process, utilizing electron microscopy to assess their structural attributes and enabling a detailed analysis of their intricate morphology. Furthermore, our team investigated the cellular composition of these microvascular fragments, subsequently confirming their ability to enhance the viability of ischemic skin flaps. RESULTS: The resulting product primarily comprised fragments with sizes ranging from 20 to 50 µm, and some exhibited a sophisticated network-like structure. Electron microscopy examination revealed the presence of collagen components in the product. Additionally, flow cytometry analysis indicated a substantial abundance of adipose-derived stem cells and endothelial cells within these microvascular fragments. Significantly, when tested in treating an ischemic skin flap in a nude mouse model, the product exhibited superior therapeutic efficacy compared to SVF cell suspension. CONCLUSION: We have successfully generated human ad-MVFs and established standardized procedures. Compared with SVF, Ad-MVFs have a better effect in the treatment of ischemic diseases. LEVEL OF EVIDENCE II: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .
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Type IV collagen is a major component of the extracellular matrix in adipose tissue. It is secreted during the lipogenic differentiation of mesenchymal stem cells, but its direct impact and mechanism on the differentiation of adipose-derived stem cells (ASCs) into lipids are unclear. In this study, ASCs were obtained from human liposuction samples and cultured. Lipogenic induction of ASCs was achieved using lipogenic induction medium. Immunofluorescence analysis revealed differential expression of type IV collagen during the early and late stages of adipogenic induction, displaying a distinct morphological encapsulation of ASCs. Silencing of type IV collagen using siRNA resulted in a significant decrease in adipogenic capacity, as indicated by reduced lipid droplet formation and downregulation of adipogenic-related gene transcription. Conversely, supplementation of the culture medium with synthetic type IV collagen demonstrated enhanced adipogenic induction efficiency, accompanied by upregulation of YAP/TAZ protein expression and its downstream target gene transcription. Furthermore, inhibition of the YAP/TAZ pathway using the inhibitor Blebbistatin attenuated the functionality of type IV collagen, leading to decreased lipid droplet formation and downregulation of adipocyte maturation-related gene expression. These findings highlight the crucial role of type IV collagen in promoting adipogenic differentiation of ASCs and suggest its involvement in the YAP/TAZ-mediated Hippo pathway.No Level Assigned This journal requires that authors assign a level of evidence to each submission to which Evidence-Based Medicine rankings are applicable. This excludes Review Articles, Book Reviews, and manuscripts that concern Basic Science, Animal Studies, Cadaver Studies, and Experimental Studies. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .
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Adipogenia , Diferenciação Celular , Colágeno Tipo IV , Humanos , Adipogenia/fisiologia , Adipogenia/genética , Colágeno Tipo IV/genética , Colágeno Tipo IV/metabolismo , Células Cultivadas , Tecido Adiposo/citologia , Adipócitos , Feminino , Células-Tronco , AdultoRESUMO
BACKGROUND: The aim was to assess the causal relationship between depression and anxiety disorders and endometrial cancer. METHOD: We performed two-sample Mendelian randomisation analysis using summary statistics from genome-wide association studies to assess associations of major depressive disorder, anxiety and stress-related disorders with endometrial cancer. The genome-wide association studies(GWASs) data were derived from participants of predominantly European ancestry included in the Genome-wide Association Research Collaboration. Inverse variance-weighted, MR-Egger and weighted median MR analyses were performed, together with a range of sensitivity analyses. RESULTS: Mendelian randomisation analysis showed no statistically significant genetic responsibility effect of anxiety and stress-related disorders on any pathological type of endometrial cancer. Only the effect of major depressive disorder under the inverse variance weighting method increasing the risk of endometrial endometrial cancer (effect 0.004 p = 0.047) and the effect of major depressive disorder under the MR-Egger method decreasing endometrial cancer of all pathology types (effect -0.691 p = 0.015) were statistically significant. Other Mendelian randomisation analyses did not show a statistically significant effect. CONCLUSION: Major depressive disorder(MDD), anxiety and stress-related disorders(ASRD) are not genetically responsible for endometrial cancer. We consider that emotional disorders may affect endometrial cancer indirectly by affecting body mass index. This study provides us with new insights to better understand the aetiology of endometrial cancer and inform prevention strategies.
This study used public genomic data to analyse association between affective disorders, including depression and anxiety, and endometrial cancer. Genes treated as instrumental variables help us understand the causal link between affective disorders and endometrial cancer through bioinformatics. In addition to this, we added type 2 diabetes, body mass index, polycystic ovary syndrome, and age at menopause for multivariate Mendelian randomisation analyses with the aim of reducing confounding bias. Because we consider these factors may potentially influence the relationship between affective disorders and endometrial cancer. Ultimately we believe that the association between depression and endometrial cancer is not as strong as that of obesity, due to the genetic correlation between depression and obesity.
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Carcinoma Endometrioide , Transtorno Depressivo Maior , Neoplasias do Endométrio , Humanos , Feminino , Transtorno Depressivo Maior/genética , Estudo de Associação Genômica Ampla , Neoplasias do Endométrio/genética , Ansiedade , Polimorfismo de Nucleotídeo Único , Análise da Randomização MendelianaRESUMO
BACKGROUND: Persistent macrophage infiltration may lead to adverse consequences, such as calcifications and nodules in fat grafts. Lymphatic vessels, which transport inflammatory cells, are involved in regulating inflammatory responses. Less is known, however, about lymphatic vessels after fat grafting. OBJECTIVES: The aim of this study was to explore the regulation of fat graft survival by lymphatic vessels. METHODS: A common adipose graft model was constructed to assess the processes responsible for changes in the number of lymphatic vessels in grafts. Adipose tissue samples from C57/BL6 mice and green fluorescent protein-expressing mice were cross-grafted to determine the source of lymphatic vessels. The number of lymphatic vessels in the grafts was increased by treatment with vascular endothelial growth factor C, and the effects of this increase on fat grafting were evaluated. RESULTS: The number of lymphatic vessels was greater in postgrafted fat than in inguinal fat before transplantation, with lymphatic vessels in these grafts gradually transitioning from donor to recipient sources. Lymphatic vessels grew more slowly than blood vessels during early stages of grafting; during later stages, however, the number of blood vessels declined markedly, with more lymphatic vessels than blood vessels being observed 60 days after grafting. Vascular endothelial growth factor C treatment increased graft lymphatics and distant volume retention, while reducing fibrosis and oil sacs. Lymphatic vessels acted as drainage channels for macrophages, with the degree of sustained macrophage infiltration decreasing with increases in the number of lymphatic vessels. CONCLUSIONS: Increasing the number of lymphatic vessels is beneficial for fat graft survival, which may be related to a reduction in prolonged macrophage infiltration.
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We performed a retrospective analysis of influenza A and B virus antigen detection data in children in Sichuan Province from January 2019 to December 2021, with the goal of studying the impact of the COVID-19 pandemic on influenza circulation in children in Sichuan, China. During the pandemic, both the number of specimens and the positive rates of the influenza virus fell dramatically. The positivity for influenza A virus decreased from 22.5% in 2019 to 9.9% in 2020 to 0.2% in 2021 (p < 0.001). The lowest and highest positive rates for the influenza B virus occurred in 2020 and 2021, respectively, with a statistically significant 3-year comparison (p < 0.001). During the pandemic, the annual positivity remained higher in school-age than in preschoolers, while there was no difference in the annual positivity between the two gender groups, both consistent with the prepandemic results. During the pandemic, the seasonality of influenza A and B was different from that before the pandemic. In 2019, the epidemic season for influenza A was autumn and winter, while the epidemic season for influenza B was winter and spring. Seasonal changes in influenza A were insignificant after the pandemic, and influenza B became predominant in 2021, with a high prevalence in the autumn. Although influenza activity decreased during the COVID-19 pandemic, one should be on the lookout for a possible rebound in influenza circulation in the future.
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COVID-19 , Influenza Humana , Orthomyxoviridae , Criança , Humanos , Pandemias , COVID-19/epidemiologia , Prevalência , Estudos Retrospectivos , China/epidemiologia , Estações do AnoRESUMO
Driven by intense laser fields, the outgoing photoelectrons in molecules possess a quiver motion, resulting in the rise of the effective ionization potential. The coupling of the field-dressed ionization potential with abundant molecular dynamics complicates the laser-molecule interactions. Here, we demonstrate an approach to resolve photoelectron releasing order in the dissociative and non-dissociative channels of multiphoton ionization driven by an orthogonally polarized two-color femtosecond laser pulse. The photoelectron kinetic energy releases and the regular nodes in the photoelectron angular distributions due to the participation of different continuum partial waves allow us to deduce the field-dressed ionization potential of various channels. It returns the ponderomotive energy experienced by the outgoing electron and reveals the corresponding photoionization instants within the laser pulse. Our results provide a route to explore the complex strong-field ionization dynamics of molecules using two-dimensional photoelectron momentum spectroscopy.
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Multiphoton light-matter interactions invoke a so-called "black box" in which the experimental observations contain the quantum interference between multiple pathways. Here, we employ polarization-controlled attosecond photoelectron metrology with a partial wave manipulator to deduce the pathway interference within this quantum 'black box" for the two-photon ionization of neon atoms. The angle-dependent and attosecond time-resolved photoelectron spectra are measured across a broad energy range. Two-photon phase shifts for each partial wave are reconstructed through the comprehensive analysis of these photoelectron spectra. We resolve the quantum interference between the degenerate pâdâp and pâsâp two-photon ionization pathways, in agreement with our theoretical simulations. Our approach thus provides an attosecond time-resolved microscope to look inside the "black box" of pathway interference in ultrafast dynamics of atoms, molecules, and condensed matter.
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Attosecond time-resolved electron tunneling dynamics have been investigated by using attosecond angular streaking spectroscopy, where a clock reference to the laser field vector is required in atomic strong-field ionization and the situation becomes complicated in molecules. Here we reveal a resonant ionization process via a transient state by developing an electron-tunneling-site-resolved molecular attoclock in Ar-Kr^{+}. Two distinct deflection angles are observed in the photoelectron angular distribution in the molecular frame, corresponding to the direct and resonant ionization pathways. We find the electron is temporally trapped in the Coulomb potential wells of the Ar-Kr^{+} before finally releasing into the continuum when the electron tunnels through the internal barrier. By utilizing the direct tunneling ionization as a self-referenced arm of the attoclock, the time delay of the electron trapped in the resonant state is revealed to be 3.50±0.04 fs. Our results give an impetus to exploring the ultrafast electron dynamics in complex systems and also endow a semiclassical presentation of the electron trapping dynamics in a quantum resonant state.
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A series of 6-benzyloxyphthalides were designed and synthesized as potent monoamine oxidase B inhibitors with antioxidant and anti-neuroinflammatory activities. The representative compounds 8f and 14a exhibited excellent selective MAO-B inhibition activity (IC50 = 1.33 nM, SI = 865; IC50 = 0.02 nM, SI = 40250, respectively) and moderate antioxidant activity (0.34 and 0.36 Trolox equivalent, respectively). Further studies showed that they were competitive and quasi-reversible MAO-B inhibitors. In cellular experiments, they could significantly decrease the production of NO and TNF-α in LPS-stimulated BV-2 cells to perform their in vitro anti-neuroinflammatory activities. Moreover, BBB permeability study and the predicted physicochemical properties indicated they were suitable for the CNS. Finally, in in vivo acute and subacute MPTP-induced mice model of PD, 8f and 14a could significantly improve most behavioral disorders, restore the DA content and decrease the MDA content in the mice striatum, exhibiting better anti-PD effects than clinically used safinamide. Hence, compounds 8f and 14a are identified in our studies as prospective prototype in the research of innovative multifunctional drugs for Parkinson's disease treatment.
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Inibidores da Monoaminoxidase , Doença de Parkinson , Animais , Antioxidantes/farmacologia , Antioxidantes/uso terapêutico , Dopaminérgicos/farmacologia , Camundongos , Monoaminoxidase/metabolismo , Inibidores da Monoaminoxidase/química , Inibidores da Monoaminoxidase/farmacologia , Inibidores da Monoaminoxidase/uso terapêutico , Doença de Parkinson/tratamento farmacológico , Estudos Prospectivos , Relação Estrutura-AtividadeRESUMO
BACKGROUND The prognostic value of the hemoglobin/red blood cell distribution width ratio in primary hepatocellular carcinoma remains unknown. This study aimed to analyze the correlation between hemoglobin/red blood cell distribution width ratio and hepatocellular carcinoma prognosis. MATERIAL AND METHODS Medical records of hepatocellular carcinoma patients were analyzed retrospectively. The hemoglobin/red blood cell distribution width ratio cut-off value was determined as 0.987 by receiver operating characteristic curve analysis. Patients were divided into high- and low-level groups, and the clinical data were compared. The correlation among the ratio levels, progression-free survival, and overall survival was measured with univariate and multivariate Cox regression analyses. The prognostic utility of the ratio combined with alpha-fetoprotein was analyzed using Kaplan-Meier survival curves and log-rank detection, and the correlation between the ratio and tumor staging was studied using one-way analysis of variance. RESULTS This study included 252 patients. Sex, smoking and alcohol consumption history, body mass index, surgery, staging, platelet/lymphocyte ratio, and hemoglobin/red blood cell distribution width ratio were associated with progression-free and overall survival (P<0.05). The ratio, alpha-fetoprotein, hemoglobin, staging, and surgery were independent risk factors for progression-free survival (P<0.05), and the ratio, alpha-fetoprotein, hemoglobin, body mass index, HBsAg, staging, and surgery were independent risk factors for overall survival (P<0.05). Patients with low ratio levels and high alpha-fetoprotein levels had the worst prognosis. CONCLUSIONS Low hemoglobin/red blood cell distribution width ratio levels are associated with poor patient prognosis and are potential tumor prognosis markers.
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Carcinoma Hepatocelular , Neoplasias Hepáticas , Carcinoma Hepatocelular/patologia , Eritrócitos/patologia , Hemoglobinas/análise , Humanos , Neoplasias Hepáticas/patologia , Prognóstico , Estudos Retrospectivos , alfa-Fetoproteínas/análiseRESUMO
BACKGROUND: The incidence of Takotsubo syndrome (TTS), also known as the broken heart syndrome or stress cardiomyopathy, is increasing worldwide. The understanding of its prognosis has been progressively evolving and currently appears to be poorer than previously thought, which has attracted the attention of researchers. An attempt to recognize the awareness of this condition among the general population drove us to analyze the dissemination of this topic on TikTok, a popular short-video-based social media platform. We found a considerable number of videos on TTS on TikTok; however, the quality of the presented information remains unknown. OBJECTIVE: The aim of this study was to analyze the quality and audience engagement of TTS-related videos on TikTok. METHODS: Videos on the TikTok platform were explored on August 2, 2021 to identify those related to TTS by using 6 Chinese keywords. A total of 2549 videos were found, of which 80 met our inclusion criteria and were evaluated for their characteristics, content, quality, and reliability. The quality and reliability were rated using the DISCERN instrument and the Journal of the American Medical Association (JAMA) criteria by 2 reviewers independently, and a score was assigned. Descriptive statistics were generated, and the Kruskal-Wallis test was used for statistical analysis. Multiple linear regression was performed to evaluate the association between audience engagement and other factors such as video content, video quality, and author types. RESULTS: The scores assigned to the selected video content were low with regard to the diagnosis (0.66/2) and management (0.34/2) of TTS. The evaluated videos were found to have an average score of 36.93 out of 80 on the DISCERN instrument and 1.51 out of 4 per the JAMA criteria. None of the evaluated videos met all the JAMA criteria. The quality of the relayed information varied by source (All P<.05). TTS-related videos made by health care professionals accounted for 28% (22/80) of all the evaluated videos and had the highest DISCERN scores with an average of 40.59 out of 80. Multiple linear regression analysis showed that author types that identified as health professionals (exponentiated regression coefficient 17.48, 95% CI 2.29-133.52; P=.006) and individual science communicators (exponentiated regression coefficient 13.38, 95% CI 1.83-97.88; P=.01) were significant and independent determinants of audience engagement (in terms of the number of likes). Other author types of videos, video content, and DISCERN document scores were not associated with higher likes. CONCLUSIONS: We found that the quality of videos regarding TTS for patient education on TikTok is poor. Patients should be cautious about health-related information on TikTok. The formulation of a measure for video quality review is necessary, especially when the purpose of the published content is to educate and increase awareness on a health-related topic.