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1.
Proc Natl Acad Sci U S A ; 121(16): e2318935121, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38588421

RESUMO

Glucose is required for generating heat during cold-induced nonshivering thermogenesis in adipose tissue, but the regulatory mechanism is largely unknown. CREBZF has emerged as a critical mechanism for metabolic dysfunction-associated steatotic liver disease (MASLD), formerly known as nonalcoholic fatty liver disease (NAFLD). We investigated the roles of CREBZF in the control of thermogenesis and energy metabolism. Glucose induces CREBZF in human white adipose tissue (WAT) and inguinal WAT (iWAT) in mice. Lys208 acetylation modulated by transacetylase CREB-binding protein/p300 and deacetylase HDAC3 is required for glucose-induced reduction of proteasomal degradation and augmentation of protein stability of CREBZF. Glucose induces rectal temperature and thermogenesis in white adipose of control mice, which is further potentiated in adipose-specific CREBZF knockout (CREBZF FKO) mice. During cold exposure, CREBZF FKO mice display enhanced thermogenic gene expression, browning of iWAT, and adaptive thermogenesis. CREBZF associates with PGC-1α to repress thermogenic gene expression. Expression levels of CREBZF are negatively correlated with UCP1 in human adipose tissues and increased in WAT of obese ob/ob mice, which may underscore the potential role of CREBZF in the development of compromised thermogenic capability under hyperglycemic conditions. Our results reveal an important mechanism of glucose sensing and thermogenic inactivation through reversible acetylation.


Assuntos
Tecido Adiposo Marrom , Glucose , Camundongos , Humanos , Animais , Glucose/metabolismo , Tecido Adiposo Marrom/metabolismo , Acetilação , Tecido Adiposo Branco/metabolismo , Metabolismo Energético , Obesidade/genética , Obesidade/metabolismo , Termogênese/genética , Camundongos Endogâmicos C57BL , Fatores de Transcrição de Zíper de Leucina Básica/metabolismo
2.
Vet Parasitol ; 328: 110167, 2024 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-38518713

RESUMO

Tetrahymena piriformis belongs to the ciliated protists (ciliates), causing severe economic losses in aquaculture. Chemical drugs currently used usually have toxic side effects, and there is no specific drug against Tetrahymena. Therefore, it is an urgent need to identify new antiparasitic lead compounds. In the present study, the in vitro parasiticidal activity of ethyl acetate (EtOAc) extracts and water extracts from 22 selected traditional Chinese medicines (TCMs) were evaluated against T. piriformis. The EtOAc extract of P. corylifolia turned out to be the most active with the minimum parasiticidal concentration of 100 mg/L within 3 h. Thus, it was separated into 12 fractions by the first-dimensional (D1) normal phase liquid chromatography (NPLC), meanwhile combining with in vitro antiparasitic tests for activity tracking. Subsequently, 8 flavonoids were identified in the active fractions by the second-dimensional (D2) reverse phase liquid chromatography (RPLC) tandem high-resolution mass spectrometry. According to the results, 5 flavonoids were selected for in vitro antiparasitic test, of which isobavachalcone showed the minimum parasiticidal concentration of 3.125 mg/L in 2 h. Bathing treatment of infected guppies with isobavachalcone could significantly reduce the burden of T. piriformis, obtaining a 24-h median effective concentration (24-h EC50) value of 1.916 mg/L. And the concentration of isobavachalcone causing guppies to die within 24 h is 39 times than that of 24-h EC50. The results demonstrated that isobavachalcone has the potential to be developed into a novel commercial fish drug against T. piriformis.

3.
Adv Sci (Weinh) ; 11(13): e2306685, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38286660

RESUMO

Chronic adipose tissue inflammation accompanied by macrophage accumulation and activation is implicated in the pathogenesis of insulin resistance and type 2 diabetes in humans. The transcriptional coregulator CREBZF is a key factor in hepatic metabolism, yet its role in modulating adipose tissue inflammation and type 2 diabetes remains elusive. The present study demonstrates that overnutrition-induced CREBZF links adipose tissue macrophage (ATM) proinflammatory activation to insulin resistance. CREBZF deficiency in macrophages, not in neutrophils, attenuates macrophage infiltration in adipose, proinflammatory activation, and hyperglycemia in diet-induced insulin-resistant mice. The coculture assays show that macrophage CREBZF deficiency improves insulin sensitivity in primary adipocytes and adipose tissue. Mechanistically, CREBZF competitively inhibits the binding of IκBα to p65, resulting in enhanced NF-κB activity. In addition, bromocriptine is identified as a small molecule inhibitor of CREBZF in macrophages, which suppresses the proinflammatory phenotype and improves metabolic dysfunction. Furthermore, CREBZF is highly expressed in ATM of obese humans and mice, which is positively correlated with proinflammatory genes and insulin resistance in humans. This study identifies a previously unknown role of CREBZF coupling ATM activation to systemic insulin resistance and type 2 diabetes.


Assuntos
Fatores de Transcrição de Zíper de Leucina Básica , Diabetes Mellitus Tipo 2 , Resistência à Insulina , Animais , Humanos , Camundongos , Tecido Adiposo/metabolismo , Fatores de Transcrição de Zíper de Leucina Básica/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Inflamação/metabolismo , Resistência à Insulina/genética , Macrófagos/metabolismo , Obesidade/metabolismo
4.
Phys Rev Lett ; 132(2): 021401, 2024 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-38277602

RESUMO

In recent years, there has been significant interest in the field of extended black hole thermodynamics, where the cosmological constant and/or other coupling parameters are treated as thermodynamic variables. Drawing inspiration from the Iyer-Wald formalism, which reveals the intrinsic and universal structure of conventional black hole thermodynamics, we illustrate that a proper extension of this formalism also unveils the underlying theoretical structure of extended black hole thermodynamics. As a remarkable consequence, for any gravitational theory described by a diffeomorphism invariant action, it is always possible to construct a consistent extended thermodynamics using this extended formalism.

5.
Acta Biochim Biophys Sin (Shanghai) ; 56(1): 106-113, 2024 01 25.
Artigo em Inglês | MEDLINE | ID: mdl-38151997

RESUMO

The regulation of various types of cell death may help to restore the normal physiological function of cells and play a protective role in sepsis. In the current study, we explore the role of programmed cell necrosis in sepsis and the underlying mechanisms. The septic rat model is established by Cecal-ligation and perforation (CLP), and the in vitro model is established by LPS in IEC-6 cells. Our results demonstrate that receptor-interacting protein 1 (RIP1) is significantly upregulated in the ileum of septic rats and LPS-treated IEC-6 cells at both the mRNA and protein levels. Nec-1, an inhibitor of RIP1, reduces the protein levels of RIP1, p-RIP3, and phosphorylated mixed-lineage kinase domain-like (MLKL) (serine 358) and relieves intestinal injury in CLP-induced septic rats with decreased IL-6 and TNF-α levels. The in vitro experiments further reveal that LPS induces the colocalization of RIP1 and RIP3, resulting in the phosphorylation and translocation of MLKL to the plasma membrane in IEC-6 cells. LPS also facilitates ROS production in IEC-6 cells, but this effect is further reversed by Nec-1, si-RIP1 and si-RIP3. Furthermore, LPS-induced necrosis in IEC-6 cells is counteracted by NAC. Thus, we conclude that RIP1/RIP3-dependent programmed cell necrosis participates in intestinal injury in sepsis and may be associated with RIP1/RIP3-mediated ROS.


Assuntos
Lipopolissacarídeos , Sepse , Ratos , Animais , Espécies Reativas de Oxigênio/metabolismo , Lipopolissacarídeos/toxicidade , Necrose/metabolismo , Apoptose , Proteína Serina-Treonina Quinases de Interação com Receptores/genética , Proteína Serina-Treonina Quinases de Interação com Receptores/metabolismo , Sepse/complicações
6.
Front Psychol ; 14: 1223535, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37842690

RESUMO

Objective: With the development of information and communication technology, cyberbullying among Chinese college students has become more frequent, bringing many negative consequences to both society and students themselves. Childhood psychological maltreatment may be one of the influencing factors of cyberbullying, but its internal mechanism remains poorly understood. This study aimed to explore the relationship between childhood psychological maltreatment and cyberbullying among college students and to further explore the mediating effect of negative emotion and the moderating effect of meaning in life. Methods: In this study, 656 college students (48.7% males) were recruited to complete anonymous questionnaires assessing their perceptions of child psychological maltreatment, negative affect, meaning in life and cyberbullying. SPSS23.0 and Hayes PROCESS macro for SPSS were used to conduct statistical analysis. Results: (1) Childhood psychological maltreatment was significantly positively associated with cyberbullying; (2) Negative affect played a partially mediating role between childhood psychological maltreatment and cyberbullying; and (3) Meaning in life moderated the direct association between childhood psychological maltreatment and cyberbullying and moderated the association between negative affect and cyberbullying. Conclusion: In this study, a moderated mediation model was constructed and the internal mechanism of childhood psychological maltreatment and cyberbullying among college students was found. The results provided both theoretical contributions and practical suggestions for preventing cyberbullying.

7.
Open Life Sci ; 18(1): 20220668, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37589007

RESUMO

This meta-analysis investigated the effect of physical exercise (PE) on the levels of oxidative biomarkers in randomized controlled trials (RCTs) involving healthy subjects. We searched five databases for articles until May 1, 2023. A random-effect meta-analysis, subgroup analysis, meta-regressions as well as trim and fill method were conducted using STATA 11.0, involving ten articles. According to the results of the meta-analysis, PE had no significant effect on superoxide dismutase (SOD), glutathione peroxidase, and catalase levels. PE induced significant increase in total antioxidant status (standardized mean difference [SMD] 1.53, 95% CI 0.73-2.32), and PE could significantly reduce the level of malondialdehyde (MDA) (SMD -1.11, 95% CI -2.15 to -0.06). Sensitivity analyses and subgroup analyses showed that male participants, body mass index (BMI) <25, exercise duration between 1 and 12 weeks, resistance exercise or multicomponent exercise, and exercise of low or moderate intensity were associated with a significant PE-induced decrease in MDA concentrations. Meta-regression analysis identified the age of the participants as a confounder of the effect of PE on SOD levels. The older age of the subjects was associated in a gradient fashion with incident SOD levels. Further RCTs are required to investigate the optimal PE protocol for people of different ages and BMI as well as the effect of PE on oxidative stress.

8.
Cyberpsychol Behav Soc Netw ; 26(8): 631-639, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37406285

RESUMO

One of the far-reaching impacts of the COVID-19 pandemic is that it has become the fertile soil of cyberchondria. Adolescents' mental health was severely hit by this by-product of the COVID-19 pandemic both due to the direct effects and its indirect effects on security. This study investigated whether and how cyberchondria was associated with Chinese adolescents' mental health (i.e., well-being and depressive symptoms). Based on a large Internet sample (N = 1,108, 67.5 percent female, Mage = 16.78 years), cyberchondria, psychological insecurity, mental health, and a series of covariates were assessed. Preliminary analyses were conducted in SPSS Statistics software and main analyses were conducted in Mplus. Path analyses indicated that (a) cyberchondria was negatively associated with well-being (b = -0.12, p = 0.001) and positively associated with depressive symptoms (b = 0.17, p < 0.001); (b) psychological insecurity could fully mediate the association between cyberchondria and mental health (indirect effect well-being = -0.15, 95% confidence interval [CI -0.19 to -0.12] and indirect effect depressive symptoms = 0.15, 95% CI [0.12 to 0.19]); (c) the two dimensions (social insecurity and uncertainty) of psychological insecurity could play the mediating role in the associations between cyberchondria and mental health, uniquely and parallelly; and (d) these results did not vary by gender. This study suggests that cyberchondria may arouse individuals' psychological insecurity about interpersonal interaction and the development of events, which ultimately decreases their well-being and increases the risk of depressive symptoms. These findings facilitate the establishment and implementation of relevant prevention and intervention programs.


Assuntos
COVID-19 , Saúde Mental , Adolescente , Feminino , Humanos , Ansiedade/epidemiologia , Ansiedade/psicologia , COVID-19/epidemiologia , População do Leste Asiático/psicologia , Comportamento de Busca de Informação , Pandemias , Masculino
9.
Proc Natl Acad Sci U S A ; 120(23): e2219419120, 2023 06 06.
Artigo em Inglês | MEDLINE | ID: mdl-37252972

RESUMO

Prolyl hydroxylase domain (PHD) enzymes change HIF activity according to oxygen signal; whether it is regulated by other physiological conditions remains largely unknown. Here, we report that PHD3 is induced by fasting and regulates hepatic gluconeogenesis through interaction and hydroxylation of CRTC2. Pro129 and Pro615 hydroxylation of CRTC2 following PHD3 activation is necessary for its association with cAMP-response element binding protein (CREB) and nuclear translocation, and enhanced binding to promoters of gluconeogenic genes by fasting or forskolin. CRTC2 hydroxylation-stimulated gluconeogenic gene expression is independent of SIK-mediated phosphorylation of CRTC2. Liver-specific knockout of PHD3 (PHD3 LKO) or prolyl hydroxylase-deficient knockin mice (PHD3 KI) show attenuated fasting gluconeogenic genes, glycemia, and hepatic capacity to produce glucose during fasting or fed with high-fat, high-sucrose diet. Importantly, Pro615 hydroxylation of CRTC2 by PHD3 is increased in livers of fasted mice, diet-induced insulin resistance or genetically obese ob/ob mice, and humans with diabetes. These findings increase our understanding of molecular mechanisms linking protein hydroxylation to gluconeogenesis and may offer therapeutic potential for treating excessive gluconeogenesis, hyperglycemia, and type 2 diabetes.


Assuntos
Diabetes Mellitus Tipo 2 , Glucose , Humanos , Camundongos , Animais , Glucose/metabolismo , Prolina/metabolismo , Hidroxilação , Diabetes Mellitus Tipo 2/metabolismo , Fígado/metabolismo , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/genética , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/metabolismo , Gluconeogênese/fisiologia , Prolil Hidroxilases/metabolismo , Hepatócitos/metabolismo , Camundongos Endogâmicos C57BL
10.
Hepatology ; 78(5): 1492-1505, 2023 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-36680394

RESUMO

BACKGROUND AND AIMS: NASH has emerged as a leading cause of chronic liver disease. However, the mechanisms that govern NASH fibrosis remain largely unknown. CREBZF is a CREB/ATF bZIP transcription factor that causes hepatic steatosis and metabolic defects in obesity. APPROACH AND RESULTS: Here, we show that CREBZF is a key mechanism of liver fibrosis checkpoint that promotes hepatocyte injury and exacerbates diet-induced NASH in mice. CREBZF deficiency attenuated liver injury, fibrosis, and inflammation in diet-induced mouse models of NASH. CREBZF increases HSC activation and fibrosis in a hepatocyte-autonomous manner by stimulating an extracellular matrix protein osteopontin, a key regulator of fibrosis. The inhibition of miR-6964-3p mediates CREBZF-induced production and secretion of osteopontin in hepatocytes. Adeno-associated virus -mediated rescue of osteopontin restored HSC activation, liver fibrosis, and NASH progression in CREBZF-deficient mice. Importantly, expression levels of CREBZF are increased in livers of diet-induced NASH mouse models and humans with NASH. CONCLUSIONS: Osteopontin signaling by CREBZF represents a previously unrecognized intrahepatic mechanism that triggers liver fibrosis and contributes to the severity of NASH.


Assuntos
Hepatopatia Gordurosa não Alcoólica , Osteopontina , Animais , Humanos , Camundongos , Fatores de Transcrição de Zíper de Leucina Básica/metabolismo , Modelos Animais de Doenças , Fígado Gorduroso/genética , Fígado Gorduroso/metabolismo , Fibrose , Hepatócitos/metabolismo , Hepatócitos/patologia , Fígado/metabolismo , Fígado/patologia , Cirrose Hepática/patologia , Camundongos Endogâmicos C57BL , Hepatopatia Gordurosa não Alcoólica/genética , Hepatopatia Gordurosa não Alcoólica/metabolismo , Hepatopatia Gordurosa não Alcoólica/patologia , Osteopontina/genética , Osteopontina/metabolismo
11.
J Interpers Violence ; 38(11-12): 7355-7382, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36625317

RESUMO

Considerable developmental research has shown an association between peer victimization and subjective well-being among adolescents. However, the mediating processes and protective factors that constrain this association are less understood. To fill these gaps, we investigated whether self-esteem mediates the association between peer victimization and subjective well-being and whether forgiveness moderates the direct and indirect associations of peer victimization with adolescents' subjective well-being via self-esteem. A large sample of 2,758 adolescents (Mage = 13.53 years, SD = 1.06) from 10 middle schools in China participated in this study. Participants provided data on demographic variables, peer victimization, self-esteem, forgiveness, and subjective well-being by answering anonymous questionnaires. After controlling for demographic covariates, we found that self-esteem mediated the relationship between peer victimization and subjective well-being. Furthermore, as a protective factor, forgiveness moderated the relationship between peer victimization and self-esteem. Consistent with the protective-reactive model, when adolescents experienced more peer victimization, those with higher forgiveness levels exhibited a greater decline in self-esteem, and low self-esteem was then associated with decreased subjective well-being. These findings demonstrate the utility of examining both mediating and moderating factors in this relationship and highlight the negative impact of peer victimization on adolescent self-worth and the limited role of forgiveness as a protective factor.


Assuntos
Bullying , Vítimas de Crime , Perdão , Autoimagem , Adolescente , Humanos , População do Leste Asiático , Grupo Associado , Inquéritos e Questionários
12.
J Alzheimers Dis ; 91(4): 1527-1539, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36641675

RESUMO

BACKGROUND: Neurofibrillary tangle aggregated from anomalous hyperphosphorylated tau is a hallmark of Alzheimer's disease (AD). Trans-active response DNA-binding protein of 43 kDa (TDP-43) enhances the instability and exon (E) 10 inclusion of tau mRNA. Cytoplasmic inclusion of hyperphosphorylated TDP-43 in the neurons constitutes the third most prevalent proteinopathy of AD. Casein kinase 1δ (CK1δ) is elevated in AD brain and phosphorylates TDP-43 in vitro. OBJECTIVE: To determine the roles of CK1δ in phosphorylation, aggregation, and function of TDP-43 in the processing of tau mRNA. METHODS: The interaction and colocalization of TDP-43 and CK1δ were analyzed by co-immunoprecipitation and immunofluorescence staining. TDP-43 phosphorylation by CK1δ was determined in vitro and in cultured cells. RIPA-insoluble TDP-43 aggregates obtained by ultracentrifugation were analyzed by immunoblots. The instability and E10 splicing of tau mRNA were studied by using a reporter of green fluorescence protein tailed with 3'-untranslational region of tau mRNA and a mini-tau gene and analyzed by real-time quantitative PCR and reverse transcriptional PCR. RESULTS: We found that CK1δ interacted and co-localized with TDP-43. TDP-43 was phosphorylated by CK1δ at Ser379, Ser403/404, and Ser409/410 in vitro and in cultured cells, which was mutually enhanced. CK1δ overexpression promoted the aggregation of TDP-43 and suppressed its activity in enhancing the instability and E10 inclusion of tau mRNA. CONCLUSION: CK1δ phosphorylates TDP-43, promotes its aggregation, and inhibits its activity in promoting the instability of tau mRNA and inclusion of tau E10. Elevated CK1δ in AD brain may contribute to TDP-43 and tau pathologies directly or indirectly.


Assuntos
Caseína Quinase Idelta , Proteínas de Ligação a DNA , Proteínas tau , Humanos , Doença de Alzheimer/metabolismo , Doença de Alzheimer/patologia , Caseína Quinase Idelta/metabolismo , Células Cultivadas , Proteínas de Ligação a DNA/metabolismo , Fosforilação , RNA Mensageiro/metabolismo , Proteínas tau/metabolismo
13.
Cancer Med ; 12(3): 2493-2504, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-35909232

RESUMO

BACKGROUND: Breast cancer (BC) remains the leading cause of cancer-related deaths worldwide. High recurrence risk Luminal BC receives adjuvant chemotherapy in addition to standard hormone therapy. Considering the heterogeneity of Luminal B BC, a more accurate classification model is urgently needed. METHODS: In this study, we retrospectively reviewed the data of 1603 patients who were diagnosed with HER2-negative breast invasive ductal carcinoma. According to the expression level of PR and Ki-67 index, the Luminal B (HER2-negative) BCs were divided into three groups: ER+PR-Ki67low (ER-positive, PR-negative, and Ki-67 index <20%), ER+PR+Ki67high (ER-positive, PR-positive, and Ki-67 index ≥20%), and ER+PR-Ki67high (ER-positive, PR-negative, and Ki-67 index ≥20%). The cox proportional hazards regression model was used to evaluate the correlation between each variable and outcomes. Besides, discriminatory accuracy of the models was compared using the area under the receiver operating characteristic curve and log-rank χ2 value. RESULTS: The analysis results showed that there was a significant correlation between subtypes using this newly defined classification and overall survival (p < 0.001) and disease-free survival (DFS) (p < 0.001). Interestingly, patients in the ER+PR-Ki67high subgroup have the worst survival outcome in Luminal B (HER2-negative) subtype, similar to Triple-negative patients. Besides, the ER+PR+Ki67high has worse 5-year DFS compared with Luminal A group. There was a significant relationship between the regrouping subtype and the recurrence score index (RI) (p < 0.001). Moreover, the results showed that patients in ER+PR-Ki67high subtype were more likely to have high RI for distance recurrence (RI-DR) and local recurrence (RI-LRR). Our newly defined classification has a better discrimination ability to predict survival outcome and recurrence score of Luminal B (HER2-negative) BC patients, which may help in clinical decision-making for individual treatment.


Assuntos
Neoplasias da Mama , Receptor ErbB-2 , Humanos , Feminino , Antígeno Ki-67/metabolismo , Receptor ErbB-2/metabolismo , Estudos Retrospectivos , Neoplasias da Mama/patologia , Intervalo Livre de Doença , Receptores de Progesterona/metabolismo , Biomarcadores Tumorais/metabolismo , Prognóstico
14.
Res Child Adolesc Psychopathol ; 51(3): 355-367, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36334225

RESUMO

Despite the burgeoning literature on adolescent internet addiction (IA), the majority of studies have relied on cross-sectional designs and variable-centered analytical approaches. Therefore, little is understood about the heterogeneous developmental trajectories of adolescent IA as well as its antecedents and outcomes. This longitudinal study adopted growth mixture modeling (GMM), a person-centered approach, to identify the distinct trajectories of IA among adolescents during a three-year period. We further examined the interpersonal predictors along with a series of outcomes of different trajectories. Participants included 1,365 Chinese adolescents (Mage = 14.68 years, SD = 1.56; 46.8% girls) from two junior high schools and two senior high schools. The GMM results indicated three distinct trajectories: low-increasing (56.7%), moderate-declining (37.6%), and high-declining (5.7%) groups. In terms of interpersonal predictors, adolescents who reported poorer relationships with their parents, teachers, and schoolmates were more likely to belong to the high-declining and moderate-declining groups. In terms of outcomes, the high-declining and moderate-declining groups exhibited an increase in mental health problems (i.e., more depressive symptoms, lower self-esteem, and lower subjective well-being) and delinquent behaviors, even after controlling for their baseline levels. These findings highlight the heterogeneity of IA trajectories among adolescents, the predictive role of interpersonal factors, and different adjustment outcomes associated with IA trajectories. Therefore, prevention and intervention programs involving interpersonal relationships may be promising for adolescents at high or moderate risk of IA.


Assuntos
Transtorno de Adição à Internet , Relações Interpessoais , Feminino , Humanos , Adolescente , Masculino , Estudos Longitudinais , Estudos Transversais , Instituições Acadêmicas
15.
Opt Express ; 30(26): 46236-46247, 2022 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-36558582

RESUMO

A design of a 1 × 2 multimode 3 dB optical power splitter using tapered couplers is proposed and investigated in this paper. As an example, a 1 × 2 splitter processing five-lowest order transverse-electric-polarized modes is designed and optimized by utilizing finite difference time domain method and particle swarm optimization algorithm. To verify the feasibility of this novel design, the optimized device is fabricated on a silicon-on-insulator platform. The coupling lengths of tapered couplers are respectively 6.5 µm, 6.0 µm, 3.5 µm, 5.0 µm, 5.0 µm, 7.5 µm, 6.0 µm, 5.0 µm, and 8.0 µm. Measurement results reveal that, for the fabricated splitter, the power uniformity varies from 0.041 to 0.88 dB, the crosstalk ranges from -23.96 to -14.12 dB, and the insertion loss changes from 0.089 to 1.50 dB within a bandwidth from 1520 to 1600 nm.

16.
Front Neurol ; 13: 1047162, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36570441

RESUMO

Glioma-associated macrophage/microglia (GAM) represents a key player in shaping a unique glioma ecosystem to facilitate tumor progression and therapeutic resistance. Numerous studies have been published concerning GAM, but no relevant bibliometric study has been performed yet. Our bibliometric study aimed to comprehensively summarize and analyze the global scientific output, research hotspots, and trendy topics of publications on GAM over time. Data on publications on GAM were collected using the Web of Science (WoS). The search date was 16 January 2022, and the publications were collected from 2002 to 2021. Totally, 1,224 articles and reviews were incorporated and analyzed in the current study. It showed that the annual publications concerning GAM kept increasing over the past 20 years. The United States had the largest number of publications and total citations. Holland, Kettenmann, and Gutmann were the top three authors in terms of citation frequency. Neuro-oncology represented the most influential journal in GAM studies, with the highest H-index, total citations, and publication numbers. The paper published by Hambardzumyan in 2016 had the highest local citations. Additionally, the analysis of keywords implied that "prognosis," "tumor microenvironment," and "immunotherapy" might become research hotspots. Furthermore, trendy topics in GAM studies suggested that "immune infiltration," "immune microenvironment," "bioinformatics," "prognosis," and "immunotherapy" deserved additional attention. In conclusion, this bibliometric study comprehensively analyzed the publication trend of GAM studies for the past 20 years, in which the research hotspots and trendy topics were also uncovered. This information offered scholars critical references for conducting in-depth studies on GAM in the future.

17.
Phys Rev Lett ; 129(19): 191101, 2022 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-36399744

RESUMO

In this Letter, employing the generalized off-shell free energy, we treat black hole solutions as defects in the thermodynamic parameter space. The results show that the positive and negative winding numbers corresponding to the defects indicate the local thermodynamical stable and unstable black hole solutions, respectively. The topological number defined as the sum of the winding numbers for all the black hole branches at an arbitrary given temperature is found to be a universal number independent of the black hole parameters. Moreover, this topological number only depends on the thermodynamic asymptotic behaviors of the black hole temperature at small and large black hole limits. Different black hole systems are characterized by three classes via this topological number. This number could help us in better understanding the black hole thermodynamics and, further, shed new light on the fundamental nature of quantum gravity.

18.
Aging Dis ; 13(5): 1436-1454, 2022 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-36186129

RESUMO

Ischemic stroke is a detrimental neurological disease characterized by an irreversible infarct core surrounded by an ischemic penumbra, a salvageable region of brain tissue. Unique roles of distinct brain cell subpopulations within the neurovascular unit and peripheral immune cells during ischemic stroke remain elusive due to the heterogeneity of cells in the brain. Single-cell RNA sequencing (scRNA-seq) allows for an unbiased determination of cellular heterogeneity at high-resolution and identification of cell markers, thereby unveiling the principal brain clusters within the cell-type-specific gene expression patterns as well as cell-specific subclusters and their functions in different pathways underlying ischemic stroke. In this review, we have summarized the changes in differentiation trajectories of distinct cell types and highlighted the specific pathways and genes in brain cells that are impacted by stroke. This review is expected to inspire new research and provide directions for investigating the potential pathological mechanisms and novel treatment strategies for ischemic stroke at the level of a single cell.

19.
Mater Today Bio ; 16: 100368, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35937578

RESUMO

Implantation of cardiovascular stents is an important therapeutic method to treat coronary artery diseases. Bare-metal and drug-eluting stents show promising clinical outcomes, however, their permanent presence may create complications. In recent years, numerous preclinical and clinical trials have evaluated the properties of bioresorbable stents, including polymer and magnesium-based stents. Three-dimensional (3D) printed-shape-memory polymeric materials enable the self-deployment of stents and provide a novel approach for individualized treatment. Novel bioresorbable metallic stents such as iron- and zinc-based stents have also been investigated and refined. However, the development of novel bioresorbable stents accompanied by clinical translation remains time-consuming and challenging. This review comprehensively summarizes the development of bioresorbable stents based on their preclinical/clinical trials and highlights translational research as well as novel technologies for stents (e.g., bioresorbable electronic stents integrated with biosensors). These findings are expected to inspire the design of novel stents and optimization approaches to improve the efficacy of treatments for cardiovascular diseases.

20.
Front Neurol ; 13: 892480, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35832175

RESUMO

Sepsis-associated encephalopathy (SAE), the most popular cause of coma in the intensive care unit (ICU), is the diffuse cerebral damage caused by the septic challenge. SAE is closely related to high mortality and extended cognitive impairment in patients in septic shock. At present, many studies have demonstrated that SAE might be mainly associated with blood-brain barrier damage, abnormal neurotransmitter secretion, oxidative stress, and neuroimmune dysfunction. Nevertheless, the precise mechanism which initiates SAE and contributes to the long-term cognitive impairment remains largely unknown. Recently, a growing body of evidence has indicated that there is close crosstalk between SAE and peripheral immunity. The excessive migration of peripheral immune cells to the brain, the activation of glia, and resulting dysfunction of the central immune system are the main causes of septic nerve damage. This study reviews the update on the pathogenesis of septic encephalopathy, focusing on the over-activation of immune cells in the central nervous system (CNS) and the "neurocentral-endocrine-immune" networks in the development of SAE, aiming to further understand the potential mechanism of SAE and provide new targets for diagnosis and management of septic complications.

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