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BACKGROUND: Ischemic stroke remains the predominant contributor to mortality and disability globally. Microglia undergo rapid activation and initiate inflammatory cascade reactions by phenotypic polarization, participating in the regulation of inflammatory injury and tissue repair post-ischemic stroke. Regulating microglia-mediated neuroinflammation is a promising therapeutic strategy for ischemic stroke. Previously, we designed and synthesized a novel p55PIK inhibitor, TAT-N15 polypeptide, which presents inhibitive activity on NF-κB signaling-mediated inflammation in acute conjunctivitis and allergic rhinitis. The present study aimed to explore the therapeutic effect and mechanism of TAT-N15 on ischemia stroke. METHODS: The mouse model of transient cerebral ischemia was made using the intraluminal filament method. After being treated with daily intraperitoneal injections of TAT-N15 (10 mg/kg) for 7 d, the neurological outcomes and the cerebral infarction volume were evaluated. Histopathology of the ischemia cerebral hemisphere was observed by H&E and Nissl staining. Neuronal survival, astrogliosis, and co-labeling of CD86/Iba1 and CD206/Iba1 were detected by immunofluorescence. The cell apoptosis was estimated by TUNEL staining. The expression levels of apoptosis-associated proteins, proinflammatory cytokines, protein markers of M1 and M2 microglia, and the phosphorylation of NF-κB and STAT3 proteins in the ischemic penumbra were detected by Western blot. RESULTS: TAT-N15 treatment significantly decreased the infarct volume and alleviated neurological functional impairment, neuronal injury, and neuron apoptosis. Meanwhile, TAT-N15 treatment restrained the activation of microglia and astrocytes as well as the protein expression of proinflammatory cytokine in ischemic penumbra. Additionally, the administration of TAT-N15 treatment resulted in a significant reduction in the density of M1 phenotype microglia while concurrently increasing the density of M2 phenotype microglia within the ischemic penumbra. Finally, mechanical analysis unveiled that TAT-N15 exerted a substantial inhibitory effect on the protein expression of phosphorylated STAT3 and NF-κB. CONCLUSION: TAT-N15 may inhibit neuroinflammation via regulating microglia activation and polarization through the STAT3/NF-κB pathway, which exhibits the neuroprotection effect in ischemic stroke.
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Antiinflamatorios , Apoptosis , Modelos Animales de Enfermedad , Mediadores de Inflamación , Ratones Endogámicos C57BL , Microglía , FN-kappa B , Enfermedades Neuroinflamatorias , Fármacos Neuroprotectores , Factor de Transcripción STAT3 , Transducción de Señal , Animales , Factor de Transcripción STAT3/metabolismo , Factor de Transcripción STAT3/antagonistas & inhibidores , Transducción de Señal/efectos de los fármacos , Microglía/efectos de los fármacos , Microglía/metabolismo , Microglía/patología , FN-kappa B/metabolismo , FN-kappa B/antagonistas & inhibidores , Enfermedades Neuroinflamatorias/tratamiento farmacológico , Enfermedades Neuroinflamatorias/metabolismo , Fármacos Neuroprotectores/farmacología , Masculino , Antiinflamatorios/farmacología , Apoptosis/efectos de los fármacos , Mediadores de Inflamación/metabolismo , Encéfalo/efectos de los fármacos , Encéfalo/metabolismo , Encéfalo/patología , Ataque Isquémico Transitorio/tratamiento farmacológico , Ataque Isquémico Transitorio/metabolismo , Ataque Isquémico Transitorio/patología , Accidente Cerebrovascular Isquémico/tratamiento farmacológico , Accidente Cerebrovascular Isquémico/metabolismo , Accidente Cerebrovascular Isquémico/patología , Infarto de la Arteria Cerebral Media/tratamiento farmacológico , Infarto de la Arteria Cerebral Media/metabolismo , Infarto de la Arteria Cerebral Media/patologíaRESUMEN
Previous studies have revealed the microbial metabolism of dietary choline in the gut, leading to its conversion into trimethylamine (TMA). Polymethoxyflavones (PMFs), exemplified by tangeretin, have shown efficacy in mitigating choline-induced cardiovascular inflammation. However, the specific mechanism by which these compounds exert their effects, particularly in modulating the gut microbiota, remains uncertain. This investigation focused on tangeretin, a representative PMFs, to explore its influence on the gut microbiota and the choline-TMA conversion process. Experimental results showed that tangeretin treatment significantly attenuated the population of CutC-active bacteria, particularly Clostridiaceae and Lactobacillus, induced by choline chloride in rat models. This inhibition led to a decreased efficiency in choline conversion to TMA, thereby ameliorating cardiovascular inflammation resulting from prolonged choline consumption. In conclusion, tangeretin's preventive effect against cardiovascular inflammation is intricately linked to its targeted modulation of TMA-producing bacterial activity.
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Arteritis , Flavonas , Microbioma Gastrointestinal , Ratas , Animales , Colina/metabolismo , Metilaminas/farmacología , Metilaminas/metabolismo , Bacterias/metabolismo , Inflamación/tratamiento farmacológicoRESUMEN
BACKGROUND Despite an increasing number of published articles on intravoxel incoherent motion (IVIM) in the past decade, almost all have focused on the technique and clinical applications of IVIM, with little attention to the collective knowledge and scientific analysis of this field. The aim of the present study was to construct a knowledge framework and to explore hotspots and emerging trends concerning use of IVIM in humans. MATERIAL AND METHODS The articles concerning IVIM MRI published from 1988 to 2021 were retrieved from the Science Citation Index Expended of the Web of Science Core Collection on 17, August 2021. The downloaded data were imported into Excel 2016 and CiteSpace V for scientometric analysis. RESULTS A total of 921 articles were included in this study and most of them were published since 2012. China (n=392) was the most productive country and the Philips Healthcare (n=46) was the most productive institution. Christian Federau had the largest number of publications (n=18). An article by Andreou A et al (2013) was the most important reference with the most co-citations (n=100) and centrality (0.06). The 5 hotspots in IVIM were perfusion, diffusion-weighted imaging, intravoxel incoherent motion, apparent diffusion coefficient, and magnetic resonance imaging. The 2 frontier topics were "brain perfusion" and "accuracy". According to the clustering of co-citation analysis, "liver", "diffusion weighting", "pancreas", and "brain" were the main research directions. CONCLUSIONS Scientometric analysis of IVIM literature with CiteSpace software can provide researchers with valuable information about knowledge framework, hotspots, and emerging trends concerning IVIM in humans.
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Abdomen , Imagen de Difusión por Resonancia Magnética , Humanos , Movimiento (Física) , Imagen de Difusión por Resonancia Magnética/métodos , Páncreas , PerfusiónRESUMEN
The Younger Dryas (YD), arguably the most widely studied millennial-scale extreme climate event, was characterized by diverse hydroclimate shifts globally and severe cooling at high northern latitudes that abruptly punctuated the warming trend from the last glacial to the present interglacial. To date, a precise understanding of its trigger, propagation, and termination remains elusive. Here, we present speleothem oxygen-isotope data that, in concert with other proxy records, allow us to quantify the timing of the YD onset and termination at an unprecedented subcentennial temporal precision across the North Atlantic, Asian Monsoon-Westerlies, and South American Monsoon regions. Our analysis suggests that the onsets of YD in the North Atlantic (12,870 ± 30 B.P.) and the Asian Monsoon-Westerlies region are essentially synchronous within a few decades and lead the onset in Antarctica, implying a north-to-south climate signal propagation via both atmospheric (decadal-time scale) and oceanic (centennial-time scale) processes, similar to the Dansgaard-Oeschger events during the last glacial period. In contrast, the YD termination may have started first in Antarctica at â¼11,900 B.P., or perhaps even earlier in the western tropical Pacific, followed by the North Atlantic between â¼11,700 ± 40 and 11,610 ± 40 B.P. These observations suggest that the initial YD termination might have originated in the Southern Hemisphere and/or the tropical Pacific, indicating a Southern Hemisphere/tropics to North Atlantic-Asian Monsoon-Westerlies directionality of climatic recovery.
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BACKGROUND: Allergic rhinoconjunctivitis (ARC) is a common chronic inflammatory disease. Numerous studies on the treatment of ARC have been published. By contrast, there are few bibliometric studies on immunotherapy for ARC. The purpose of this article is to describe the current treatments for ARC and to identify the trends in immunotherapy for ARC. METHODS: Publications were searched from the Web of Science (WOS) Core Collection on April 25, 2022. CiteSpace and Microsoft Excel software were used for further bibliometric analysis. RESULTS: A total of 969 publications on immunotherapy for ARC in English were retrieved. The number of relevant publications has been continuously increasing over the past 20 years, with many of the publications coming from Germany and the United States of America. In terms of institutions, the ALK Company in Denmark, Imperial College London in United Kingdom, and Charite-Universitatsmedizin Berlin in Germany published the most articles on immunotherapy for ARC. Meanwhile, Allergy and Journal of Allergy and Clinical Immunology published the most number of studies, and Oliver Pfaar from Germany authored the most number of articles. "Subcutaneous immunotherapy," "international consensus," "allergen immunotherapy," and "recommendation" were the most popular subjects. Thus, directions in research can be predicted as studies regarding mechanisms of ARC, clinical trials, and extracts have reported high-quality results. CONCLUSION: Over the past 20 years, the overall quality of research on immunotherapy for ARC has gradually improved, allowing the introduction of specific and targeted treatment. Currently, the main focus of ARC research is the novel routes of drug delivery and combined treatment with biological agents.
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Conjuntivitis , Hipersensibilidad , Humanos , Desensibilización Inmunológica , Bibliometría , Terapia CombinadaRESUMEN
Cd-contaminated farmlands threaten food security and safety by inhibiting crop growth and Cd accumulating in edible parts. Phytoremediation is a promising option to remove Cd from farmland soil. An ideal option is to remediate Cd and produce crops simultaneously on the contaminated soil. Therefore, we chose widely planted oil crops (soybean, sunflower and rape) as experimental materials, cultured in pots filled with soils contaminated with different concentrations (10, 20, 50, and 100 mg kg-1) Cd till harvest, and then took a closed-loop method to evaluate the remediation potential of the three oil crops, including the remediating ability, yield, and quality of seeds and environmental risk of pyrolytic biochar. The results show that the order of Cd accumulation capacity in the three oil crops was sunflower > rape > soybean. The yield and quality of the three oil crops were decreased by being treated with different concentrations of Cd. In addition, the order for a decreased degree in yield of the three oil crops was sunflower < rape < soybean, and the order for a decreased degree in protein and fat content was sunflower < soybean < rape. The potential risk of seeds of the three oil crops as food/feed was sunflower/soybean < soybean/sunflower < rape. After pyrolysis of harvested three oil crops, the order for leaching toxicity/leaching potential was sunflower-biochar < soybean-biochar/rape-biochar < rape-biochar/soybean-biochar. All three oil crops could remediate Cd-contaminated soils, and their seeds could generate economic value. Closed-loop evaluation of sunflower proved it might be a good option for removing Cd from farmland soil.
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Asteraceae , Helianthus , Metales Pesados , Contaminantes del Suelo , Asteraceae/metabolismo , Biodegradación Ambiental , Cadmio/análisis , Carbón Orgánico , Productos Agrícolas/metabolismo , Helianthus/metabolismo , Metales Pesados/análisis , Suelo , Contaminantes del Suelo/análisisRESUMEN
Current therapies for ischemic stroke are insufficient due to the lack of specific drugs. This study aimed to investigate the protective activity of polyphenol extracts from Terminalia chebula against cerebral ischemia-reperfusion induced damage. Polyphenols of ethyl acetate and n-butanol fractions were extracted from T. chebula. BV2 microglial cells exposed to oxygen-glucose deprivation/reoxygenation and mice subjected to middle cerebral artery occlusion/reperfusion were treated by TPE and TPB. Cell viability, cell morphology, apoptosis, mitochondrial membrane potential, enzyme activity and signaling pathway related to oxidative stress were observed. We found that TPE and TPB showed strong antioxidant activity in vitro. The protective effects of TPE and TPB on cerebral ischemia-reperfusion injury were demonstrated by enhanced antioxidant enzyme activities, elevated level of the nucleus transportation of nuclear factor erythroid 2-related factor 2 and expressions of antioxidant proteins, with a simultaneous reduction in cell apoptosis and reactive oxygen species level. In conclusion, TPE and TPB exert neuroprotective effects by stimulating the Nrf2 signaling pathway, thereby inhibiting apoptosis.
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Fármacos Neuroprotectores , Daño por Reperfusión , Terminalia , 1-Butanol/farmacología , Animales , Antioxidantes/metabolismo , Glucosa/farmacología , Ratones , Factor 2 Relacionado con NF-E2/metabolismo , Fármacos Neuroprotectores/farmacología , Fármacos Neuroprotectores/uso terapéutico , Estrés Oxidativo , Oxígeno/farmacología , Extractos Vegetales/farmacología , Extractos Vegetales/uso terapéutico , Polifenoles/farmacología , Polifenoles/uso terapéutico , Especies Reactivas de Oxígeno/metabolismo , Daño por Reperfusión/tratamiento farmacológico , Daño por Reperfusión/metabolismo , Terminalia/metabolismoRESUMEN
BACKGROUND: Alternative splicing (AS), one of the main post-transcriptional biological regulation mechanisms, plays a key role in the progression of glioblastoma (GBM). Systematic AS profiling in GBM is limited and urgently needed. METHODS: TCGA SpliceSeq data and the corresponding clinical data were downloaded from the TCGA data portal. Survival-related AS events were identified through Kaplan-Meier survival analysis and univariate Cox analysis. Then, splicing correlation network was constructed based on these AS events and associated splicing factors. LASSO regression followed by multivariate Cox analysis was performed to validate independent AS biomarkers and to construct a risk prediction model. Enrichment analysis was subsequently conducted to explore potential signaling pathways of these AS events. RESULTS: A total of 132 TCGA GBM samples and 45,610 AS events were included in our study, among which 416 survival-related AS events were identified. An AS correlation network, including 54 AS events and 94 splicing factors, was constructed, and further functional enrichment was performed. Moreover, the novel risk prediction model we constructed displayed moderate performance (the area under the curves were > 0.7) at both one, two and three years. CONCLUSIONS: Survival-related AS events may be vital factors of both biological function and prognosis. Our findings in this study can deepen the understanding of the complicated mechanisms of AS in GBM and provide novel insights for further study. Moreover, our risk prediction model is ready for preliminary clinical applications. Further verification is required.
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Empalme Alternativo , Biomarcadores de Tumor/genética , Regulación Neoplásica de la Expresión Génica , Redes Reguladoras de Genes , Genoma Humano , Glioblastoma/patología , Factores de Empalme de ARN/genética , Terapia Combinada , Femenino , Estudios de Seguimiento , Perfilación de la Expresión Génica , Glioblastoma/genética , Glioblastoma/terapia , Humanos , Masculino , Pronóstico , Tasa de Supervivencia , TranscriptomaRESUMEN
Nowadays, soft sensor techniques have become promising solutions for enabling real-time estimation of difficult-to-measure quality variables in industrial processes. However, labeled data are often scarce in many real-world applications, which poses a significant challenge when building accurate soft sensor models. Therefore, this paper proposes a novel semi-supervised soft sensor method, referred to as ensemble semi-supervised negative correlation learning extreme learning machine (EnSSNCLELM), for industrial processes with limited labeled data. First, an improved supervised regression algorithm called NCLELM is developed, by integrating the philosophy of negative correlation learning into extreme learning machine (ELM). Then, with NCLELM as the base learning technique, a multi-learner pseudo-labeling optimization approach is proposed, by converting the estimation of pseudo labels as an explicit optimization problem, in order to obtain high-confidence pseudo-labeled data. Furthermore, a set of diverse semi-supervised NCLELM models (SSNCLELM) are developed from different enlarged labeled sets, which are obtained by combining the labeled and pseudo-labeled training data. Finally, those SSNCLELM models whose prediction accuracies were not worse than their supervised counterparts were combined using a stacking strategy. The proposed method can not only exploit both labeled and unlabeled data, but also combine the merits of semi-supervised and ensemble learning paradigms, thereby providing superior predictions over traditional supervised and semi-supervised soft sensor methods. The effectiveness and superiority of the proposed method were demonstrated through two chemical applications.
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Algoritmos , AprendizajeRESUMEN
PURPOSE: Preoperative fasting is a necessary experience for pediatric patients undergoing elective surgery. The American Society of Anesthesiologist guideline shows that preoperative fasting times were reduced and safe (no solid food up to 8 hours, no fluid or formula up to 6 hours, no breast milk up to 4 hours, and no clear fluids up to 2 hours before surgery). However, preoperative fasting is usually more prolonged than the suggested time. This study aimed to investigate the duration of preoperative fasting for elective surgery at a pediatric hospital in Shanghai, China, and compare it with the evidence from guidelines. DESIGN: The study used a descriptive cross-sectional design. METHODS: A total of 211 children under anesthesia in a Shanghai's pediatric hospital were included in the study. The preoperative fasting status was assessed using a self-administered record card of preoperative fasting developed by Chinese researchers. FINDINGS: The results indicated that the length of time fasted preoperatively was longer for all participants than that recommended by the American Society of Anesthesiologists. With the long length of fasting time, it is evident that the majority of children experienced hunger (17.5%), thirst (19.4%), and anxiety (16.1%) as indicated with 8 points of the Likert 10-point scale. The degrees of these experiences were relevant to the length of preoperative fasting time. CONCLUSIONS: A big gap was revealed between the recommendation and actual practice, and children underwent an uncomfortable experience before the surgery. These results suggest that evidence-based clinical improvement is required, and the recommended preoperative fasting instruction transform into clinical practice should be promoted.
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Ayuno , Hospitales Pediátricos , Niño , China , Estudios Transversales , Humanos , Cuidados Preoperatorios , Brechas de la Práctica ProfesionalRESUMEN
OBJECTIVE: Dietary n-3 polyunsaturated fatty acids (PUFAs), especially eicosapentaenoic acids (EPA) and docosahexaenoic acid (DHA), are proved to be effective in obesity reduction. Microalgal oil (MO) is an important alternative source of n-3 PUFAs that effectively alleviates obesity. The aim of the present study was to explore the anti-obesity effects of microalgal oil from Schizochytrium sp. (SMO) and to compare the effects of 2 SMOs (SMO1 and SMO2) with different levels of purity of n-3 PUFAs on high fat diet (HFD)-induced obesity in male C57BL/6J mice. METHODS: Mice were randomly divided into 5 groups: (1) regular chow (RC); (2) HFD; (3) HFD + fish oil (FO); (4) HFD + SMO1; and (5) HFD + SMO2. Body weight and food intake were weekly monitored. After 16 weeks of treatment, a glucose tolerance test (GTT) and an insulin tolerance test (ITT) were performed. Serum lipid profile, morphological changes in the liver and epididymal white adipose tissue (eWAT), and the mRNA expression of lipid metabolism-related genes were also examined. RESULTS: SMO treatment significantly decreased HFD-induced abdominal fat accumulation, lowered the levels of triglycerides, cholesterol, and low-density lipoprotein, as did the positive control treated with FO. Morphological examination revealed a remarkable reduction in lipid droplet formation in the liver tissue and the particle size of eWAT. An alleviation of inflammation infiltration in eWAT caused by a high-fat diet was also observed. Real-time reverse transcription-polymerase chain reaction analysis examination confirmed that microalgal oil inhibited the gene expression of fatty acid synthase, sterol responsive element-binding protein-1c, and acetyl-CoA carboxylase but promoted that of hormone-sensitive lipase and lipoprotein lipase, carnitine palmitoyltransferase-1, and uncoupling proteins in the liver and eWAT. Moreover, similar anti-obesity effects were obtained with the same dosage but different purity of n-3 PUFAs. CONCLUSIONS: As an alternative n-3 PUFAs resource, dietary intake of SMO might be beneficial to prevent HFD-induced abdominal fat accumulation.
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Grasa Abdominal/efectos de los fármacos , Dieta Alta en Grasa/efectos adversos , Grasas de la Dieta/efectos adversos , Microalgas/química , Aceites de Plantas/farmacología , Animales , Lípidos/sangre , Masculino , Ratones , Ratones Endogámicos C57BL , Obesidad/inducido químicamente , Obesidad/prevención & control , Aceites de Plantas/químicaRESUMEN
Bilayer hydrogel actuators, consisting of an actuating layer and a functional layer, show broad applications in areas such as soft robotics, artificial muscles, drug delivery and tissue engineering due to their inherent flexibility and responses to stimuli. However, to achieve the compatibility of good stimulus responses and high mechanical properties of bilayer hydrogel actuators is still a challenge. Herein, based on the double-network strategy and using the synchronous ultraviolet (UV) polymerization method, an upper critical solution temperature (UCST)-type bilayer hydrogel actuator was prepared, which consisted of a poly(acrylamide-co-acrylic acid)[MC] actuating layer and an agar/poly(N-hydroxyethyl acrylamide-co-methacrylic acid)[AHA] functional layer. The results showed that the tensile stress/strain of the bilayer hydrogel actuator was 1161.21 KPa/222.07%. In addition, the UCST of bilayer hydrogels was ~35 °C, allowing the bilayer hydrogel actuator to be curled into an "â" shape, which could be unfolded when the temperature was 65 °C, but not at a temperature of 5 °C. Furthermore, hydrogel actuators of three different shapes were designed, namely "butterfly", "cross" and "circle", all of which demonstrated good actuating performances, showing the programmable potential of bilayer hydrogels. Overall, the bilayer hydrogels prepared using double-network and synchronous UV polymerization strategies realized the combination of high mechanical properties with an efficient temperature actuation, which provides a new method for the development of bilayer hydrogel actuators.
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Oocyte in vitro maturation (IVM) based on the follicular fluid (FF) environment can exploit untapped resources, however, what FF factors regulate oocyte maturation remains unclear. This work demonstrated that serum and FF significantly promoted oocyte polar body extrusion (PBE) and subsequent embryo development, and FF was especially effective. Fibronectin 1 (FN1) was predicted as one potential candidate to regulate oocyte maturation by proteomics. FN1 transcription obviously decreased, and the protein expression significantly increased and migrated to plasma membrane or even outside during oocyte IVM. Treatment with 10 ng/mL FN1 significantly improved oocyte PBE rate. FN1 significantly upregulated the percentage of regular spindle morphology, downregulated the γ-H2AX level, decreased the levels of ROS and apoptosis, and increased GSH and mitochondrion contents by ameliorating the expression of corresponding genes. Moreover, FN1 significantly increased the p-PI3K level to enhance the activation of PI3K signaling pathway. In conclusion, this study discovers and confirms that FN1 is one factor in FF that significantly enhances oocyte maturation, and the underlying mechanism is that FN1 ameliorates oocyte nuclear and cytoplasmic maturation by promoting the activation of PI3K signaling pathway.
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Fibronectinas , Técnicas de Maduración In Vitro de los Oocitos , Femenino , Animales , Porcinos , Fibronectinas/genética , Fibronectinas/metabolismo , Fosfatidilinositol 3-Quinasas/metabolismo , Oocitos , Líquido Folicular/metabolismoRESUMEN
Branched-chain amino acid transferase 1 (BCAT1) is highly expressed in multiple cancers and is associated with poor prognosis, particularly in glioblastoma (GBM). However, the post-translational modification (PTM) mechanism of BCAT1 is unknown. Here, we investigated the cross-talk mechanisms between phosphorylation and ubiquitination modifications in regulating BCAT1 activity and stability. We found that BCAT1 is phosphorylated by branched chain ketoacid dehydrogenase kinase (BCKDK) at S5, S9, and T312, which increases its catalytic and antioxidant activity and stability. STUB1 (STIP1 homology U-box-containing protein 1), the first we found and reported E3 ubiquitin ligase of BCAT1, can also be phosphorylated by BCKDK at the S19 site, which disrupts the interaction with BCAT1 and inhibits its degradation. In addition, we demonstrate through in vivo and in vitro experiments that BCAT1 phosphorylation inhibiting its ubiquitination at multiple sites is associated with GBM proliferation and that inhibition of the BCKDK-BCAT1 axis enhances the sensitivity to temozolomide (TMZ). Overall, we identified novel mechanisms for the regulation of BCAT1 modification and elucidated the importance of the BCKDK-STUB1-BCAT1 axis in GBM progression.
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Proliferación Celular , Glioblastoma , Transaminasas , Ubiquitinación , Animales , Humanos , Ratones , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/patología , Neoplasias Encefálicas/genética , Línea Celular Tumoral , Progresión de la Enfermedad , Glioblastoma/patología , Glioblastoma/metabolismo , Glioblastoma/genética , Células HEK293 , Ratones Desnudos , Fosforilación , Proteolisis , Temozolomida/farmacología , Ubiquitina-Proteína Ligasas/metabolismo , Ubiquitina-Proteína Ligasas/genética , Transaminasas/metabolismoRESUMEN
The insulin receptor (INSR, IR) has two isoforms, IRA and IRB, through alternative splicing. However, their distinct functions in vivo remain unclear. Here we generated ß cell-specific IRB knockout (KO) mice (ßIRBKO). The KO mice displayed worsened hyperinsulinemia and hyperproinsulinemia in diet-induced obesity due to impaired proinsulin processing in ß cells. Mechanistically, loss of IRB suppresses eukaryotic translation initiation factor 4G1 (eIF4G1) by stabilizing the transcriptional receptor sterol-regulatory element binding protein 1 (SREBP1). Moreover, excessive autocrine proinsulin in ßIRBKO mice enhances the activity of extracellular signal-regulated kinase (ERK) through the remaining IRA to further stabilize nuclear SREBP1, forming a feedback loop. Collectively, our study paves the way to dissecting the isoform-specific function of IR in vivo and highlights the important roles of IRB in insulin processing and protecting ß cells from lipotoxicity in obesity.
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A passive wireless sensor is designed for real-time monitoring of a high temperature environment. The sensor is composed of a double diamond split rings resonant structure and an alumina ceramic substrate with a size of 23 × 23 × 0.5 mm3. The alumina ceramic substrate is selected as the temperature sensing material. The principle is that the permittivity of the alumina ceramic changes with the temperature and the resonant frequency of the sensor shifts accordingly. Its permittivity bridges the relation between the temperature and resonant frequency. Therefore, real time temperatures can be measured by monitoring the resonant frequency. The simulation results show that the designed sensor can monitor temperatures in the range 200~1000 °C corresponding to a resonant frequency of 6.79~6.49 GHz with shifting 300 MHz and a sensitivity of 0.375 MHz/°C, and demonstrate the quasi-linear relation between resonant frequency and temperature. The sensor has the advantages of wide temperature range, good sensitivity, low cost and small size, which gives it superiority in high temperature applications.
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Ischemic stroke remains the predominant cause of mortality and functional impairment among the adult populations globally. Only a minority of ischemic stroke patients are eligible to receive intravascular thrombolysis or mechanical thrombectomy therapy within the optimal time window. Among those stroke survivors, around two-thirds suffer neurological dysfunctions over an extended period. Establishing a stable and repeatable experimental ischemic stroke model is extremely significant for further investigating the pathophysiological mechanisms and developing effective therapeutic strategies for ischemic stroke. The middle cerebral artery (MCA) represents the predominant location of ischemic stroke in humans, with the MCA occlusion serving as the frequently employed model of focal cerebral ischemia. In this protocol, we describe the methodology of establishing the distal MCA occlusion (dMCAO) model through transcranial electrocoagulation in C57BL/6 mice. Since the occlusion site is located at the cortical branch of MCA, this model generates a moderate infarcted lesion restricted to the cortex. Neurological behavioral and histopathological characterization have demonstrated visible motor dysfunction, neuron degeneration, and pronounced activation of microglia and astrocytes in this model. Thus, this dMCAO mouse model provides a valuable tool for investigating the ischemiastroke and worth of popularization.
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Arteriopatías Oclusivas , Isquemia Encefálica , Accidente Cerebrovascular Isquémico , Accidente Cerebrovascular , Ratones , Humanos , Animales , Ratones Endogámicos C57BL , Accidente Cerebrovascular/terapia , Accidente Cerebrovascular/complicaciones , Isquemia Encefálica/terapia , Isquemia Encefálica/patología , Infarto de la Arteria Cerebral Media/patología , Arteriopatías Oclusivas/complicaciones , Arteria Cerebral Media/patologíaRESUMEN
INTRODUCTION: The anti-angiogenic agent vascular endothelial growth factor 165b (VEGF165b) mutant (mVEGF165b), which was developed by our laboratory, has superior antitumor activity to that of native VEGF165b; however, its mechanism of action and druggability need further exploration. METHODS: Using the commercial anti-angiogenic drug bevacizumab as a positive control, the mechanism and developability of mVEGF165b were evaluated and explored. The Cell Counting Kit-8 assay was performed to evaluate the effects of mVEGF165b and bevacizumab alone on the proliferation of human umbilical vein endothelial cells (HUVECs). Meanwhile, the inhibitory effects of mVEGF165b and bevacizumab combined with paclitaxel in a mouse model of breast cancer were assessed. Immunohistochemistry was used to detect their effects on tumor vascular maturation, and the terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assay was used to detect the apoptosis of tumor cells. RESULTS: In vitro cell experiments confirmed that mVEGF165b inhibited the proliferation of HUVECs with an efficacy equivalent to that of bevacizumab. mVEGF165b and bevacizumab combined with paclitaxel significantly delayed the growth of breast cancer in mice. Immunohistochemistry and the TUNEL assay showed that mVEGF165b and bevacizumab combined with paclitaxel-induced higher vascular maturity and more apoptosis than paclitaxel alone. CONCLUSION: mVEGF165b showed similar efficacy and mechanism of action as bevacizumab, indicating its potential to be developed into a safe and effective anti-angiogenic drug.
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Neoplasias de la Mama , Paclitaxel , Humanos , Animales , Ratones , Femenino , Paclitaxel/farmacología , Bevacizumab/farmacología , Inhibidores de la Angiogénesis/farmacología , Factor A de Crecimiento Endotelial Vascular/genética , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/metabolismo , Apoptosis , Células Endoteliales de la Vena Umbilical Humana/metabolismo , Línea Celular TumoralRESUMEN
OBJECTIVE: To study the effect and mechanism of electroacupuncture at "Baihui, Yintang and Shuigou" acupoints on learning and memory in Post-Stroke Cognitive Impairment (PSCI) mice. METHODS: 52 male C57BL/6 mice were used to establish a MACO model by using middle cerebral artery occlusion (n=38), while the Sham only ligated at the distal end of the external carotid artery (n=14). After 28 days, the MCAO was divided into three groups based on the escape latency of Morris water maze: non cognitive impairment (MNP), post-stroke cognitive impairment (MP), and electroacupuncture intervention group (MPEA). In the MPEA, electroacupuncture at "Baihui and Yintang" acupoints was performed for 20 minutes (density wave, 2/15HZ and 1mA) supplemented by acupuncture at "Shuigou" acupoints once a day with a 6-day course of treatment. The intervention last for 2 courses with a 1-day interval. Morris water maze was used to detect the cognitive function of mice in each group; Nissl staining was used to observe hippocampal neurons; Western blot was used to detect the expression of GluA1, Syp, and Syt-1 in the affected hippocampus; IHC was used to detect the expression of Syp in the CA1 region of the contralateral hippocampus. CONCLUSION: Acupuncture at points "Baihui, Yintang, and Shuigou" can improve the learning and memory abilities of PSCI mice, and its mechanism is related to synaptic plasticity of hippocampus.