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Intrinsically stretchable electronics with skin-like mechanical properties have been identified as a promising platform for emerging applications ranging from continuous physiological monitoring to real-time analysis of health conditions, to closed-loop delivery of autonomous medical treatment1-7. However, current technologies could only reach electrical performance at amorphous-silicon level (that is, charge-carrier mobility of about 1 cm2 V-1 s-1), low integration scale (for example, 54 transistors per circuit) and limited functionalities8-11. Here we report high-density, intrinsically stretchable transistors and integrated circuits with high driving ability, high operation speed and large-scale integration. They were enabled by a combination of innovations in materials, fabrication process design, device engineering and circuit design. Our intrinsically stretchable transistors exhibit an average field-effect mobility of more than 20 cm2 V-1 s-1 under 100% strain, a device density of 100,000 transistors per cm2, including interconnects and a high drive current of around 2 µA µm-1 at a supply voltage of 5 V. Notably, these achieved parameters are on par with state-of-the-art flexible transistors based on metal-oxide, carbon nanotube and polycrystalline silicon materials on plastic substrates12-14. Furthermore, we realize a large-scale integrated circuit with more than 1,000 transistors and a stage-switching frequency greater than 1 MHz, for the first time, to our knowledge, in intrinsically stretchable electronics. Moreover, we demonstrate a high-throughput braille recognition system that surpasses human skin sensing ability, enabled by an active-matrix tactile sensor array with a record-high density of 2,500 units per cm2, and a light-emitting diode display with a high refreshing speed of 60 Hz and excellent mechanical robustness. The above advancements in device performance have substantially enhanced the abilities of skin-like electronics.
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Desenho de Equipamento , Pele , Transistores Eletrônicos , Dispositivos Eletrônicos Vestíveis , Humanos , Silício , Nanotubos de Carbono , TatoRESUMO
Next-generation light-emitting displays on skin should be soft, stretchable and bright1-7. Previously reported stretchable light-emitting devices were mostly based on inorganic nanomaterials, such as light-emitting capacitors, quantum dots or perovskites6-11. They either require high operating voltage or have limited stretchability and brightness, resolution or robustness under strain. On the other hand, intrinsically stretchable polymer materials hold the promise of good strain tolerance12,13. However, realizing high brightness remains a grand challenge for intrinsically stretchable light-emitting diodes. Here we report a material design strategy and fabrication processes to achieve stretchable all-polymer-based light-emitting diodes with high brightness (about 7,450 candela per square metre), current efficiency (about 5.3 candela per ampere) and stretchability (about 100 per cent strain). We fabricate stretchable all-polymer light-emitting diodes coloured red, green and blue, achieving both on-skin wireless powering and real-time displaying of pulse signals. This work signifies a considerable advancement towards high-performance stretchable displays.
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The rapid development of wearable and implantable electronics has enabled the real-time transmission of electrophysiological signals in situ, thus allowing the precise monitoring and regulation of biological functions. Devices based on organic materials tend to have low moduli and intrinsic stretchability, making them ideal choices for the construction of seamless bioelectronic interfaces. In this case, as an organic ionic-electronic conductor, poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS) has low impedance to offer a high signal-to-noise ratio for monitoring bioelectrical signals, which has become one of the most promising conductive polymers. However, the initial conductivity and stretchability of pristine PEDOT:PSS are insufficient to meet the application requirements, and there is a trade-off between their improvement. In addition, PEDOT:PSS has poor stability in aqueous environments due to the hygroscopicity of the PSS chains, which severely limits its long-term applications in water-rich bioelectronic interfaces. Considering the growing demands of multi-function integration, the high-resolution fabrication of electronic devices is urgent. It is a great challenge to maintain both electrical and mechanical performance after miniaturization, particularly at feature sizes below 100 µm. In this review, we focus on the combined improvement in the conductivity and stretchability of PEDOT:PSS, as well as the corresponding mechanisms in detail. Also, we summarize the effective strategies to improve the stability of PEDOT:PSS in aqueous environments, which plays a vital role in long-term applications. Finally, we introduce the reliable micropatterning technologies and PEDOT:PSS-based stretchable optoelectronic devices applied at bio-interfaces.
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Compostos Bicíclicos Heterocíclicos com Pontes , Polímeros , Dispositivos Eletrônicos Vestíveis , Polímeros/química , Compostos Bicíclicos Heterocíclicos com Pontes/química , Poliestirenos/química , Eletrônica , Humanos , Condutividade Elétrica , TiofenosRESUMO
Long-term epidermal recording of bioelectricity is of paramount importance for personal health monitoring. It requires stretchable and dry film electrodes that can be seamlessly integrated with skin. The simultaneous achievement of high conductivity and skin-like ductility of conducting materials is a prerequisite for reliable signal transduction at the dynamic interface, which is also the bottleneck of epidermal electrophysiology. Here, carbon nanotubes (CNTs) are introduced as "conjugation linkers" into a topologically plasticized conducting polymer (PEDOT:PSS). A thin-film electrode with high conductivity (≈3250 S cm-1) and high stretchability (crack-onset strain>100%) is obtained. In particular, the conjugation linker enables the high volumetric capacitance and the low film resistance, both of which synergically reduce the interfacial impedance. The capabilities of this electrode is further demonstrated in the precise recording of various electrophysiological signals.
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BACKGROUND: Inflammatory macrophage infiltration plays a critical role in acute kidney disease induced by ischemia-reperfusion (IRI-AKI). Calycosin is a natural flavone with multiple bioactivities. This study aimed to investigate the therapeutic role of calycosin in IRI-AKI and its underlying mechanism. METHODS: The renoprotective and anti-inflammatory effects of calycosin were analyzed in C57BL/6 mice with IRI-AKI and lipopolysaccharide (LPS)-stimulated RAW 264.7 cells. RNA-seq was used for mechanism investigation. The molecular target of calycosin was screened by in silico methods and validated by surface plasmon resonance (SPR). Macrophage chemotaxis was analyzed using Transwell and agarose gel spot assays. RESULTS: Calycosin treatment significantly reduced serum creatinine and urea nitrogen and attenuated tubular destruction in IRI-AKI mice. Additionally, calycosin markedly suppressed NF-κB signaling activation and the expression of inflammatory mediators IL-1ß and TNF-α in IRI-AKI kidneys and LPS-stimulated RAW 264.7 cells. Interestingly, RNA-seq revealed calycosin remarkably downregulated chemotaxis-related pathways in RAW 264.7 cells. Among the differentially expressed genes, Ccl2/MCP-1, a critical chemokine mediating macrophage inflammatory chemotaxis, was downregulated in both LPS-stimulated RAW 264.7 cells and IRI-AKI kidneys. Consistently, calycosin treatment attenuated macrophage infiltration in the IRI-AKI kidneys. Importantly, in silico target prediction, molecular docking, and SPR assay demonstrated that calycosin directly binds to macrophage migration inhibitory factor (MIF). Functionally, calycosin abrogated MIF-stimulated NF-κB signaling activation and Ccl2 expression and MIF-mediated chemotaxis in RAW 264.7 cells. CONCLUSIONS: In summary, calycosin attenuates IRI-AKI by inhibiting MIF-mediated macrophage inflammatory chemotaxis, suggesting it could be a promising therapeutic agent for the treatment of IRI-AKI.
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Injúria Renal Aguda , Quimiotaxia , Isoflavonas , Fatores Inibidores da Migração de Macrófagos , Macrófagos , Traumatismo por Reperfusão , Animais , Masculino , Camundongos , Injúria Renal Aguda/tratamento farmacológico , Injúria Renal Aguda/metabolismo , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/uso terapêutico , Quimiotaxia/efeitos dos fármacos , Oxirredutases Intramoleculares/metabolismo , Oxirredutases Intramoleculares/genética , Isoflavonas/farmacologia , Isoflavonas/uso terapêutico , Rim/efeitos dos fármacos , Rim/patologia , Lipopolissacarídeos , Macrófagos/efeitos dos fármacos , Camundongos Endogâmicos C57BL , NF-kappa B/metabolismo , Células RAW 264.7 , Traumatismo por Reperfusão/tratamento farmacológicoRESUMO
The cyclisation mechanism of the fungal fusicoccane (FC)-type diterpene synthase (DTS) TadA was investigated by extensive isotopic labelling experiments, and the pH-dependency of the product selectivity of this enzyme was explored. These studies provide new insights into the cyclisation mechanisms of FC-type DTSs.
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Alquil e Aril Transferases , Diterpenos , Diterpenos/química , Diterpenos/metabolismo , Alquil e Aril Transferases/metabolismo , Ciclização , Concentração de Íons de Hidrogênio , Estrutura MolecularRESUMO
Although electro-Fenton (EF) processes can avoid the safety risks raised by concentrated hydrogen peroxide (H2O2), the Fe(III) reduction has always been either unstable or inefficient at high pH, resulting in catalyst deactivation and low selectivity of H2O2 activation for producing hydroxyl radicals (â¢OH). Herein, we provided a strategy to regulate the surface dipole moment of TiO2 by Fe anchoring (TiO2-Fe), which, in turn, substantially increased the H2O2 activation for â¢OH production. The TiO2-Fe catalyst could work at pH 4-10 and maintained considerable degradation efficiency for 10 cycles. Spectroscopic analysis and a theoretical study showed that the less polar Fe-O bond on TiO2-Fe could finely tune the polarity of H2O2 to alter its empty orbital distribution, contributing to better ciprofloxacin degradation activity within a broad pH range. We further verified the critical role of the weakened polarity of H2O2 on its homolysis into â¢OH by theoretically and experimentally investigating Cu-, Co-, Ni-, Mn-, and Mo-anchored TiO2. This concept offers an avenue for elaborate design of green, robust, and pH-universal cathodic Fenton-like catalysts and beyond.
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Peróxido de Hidrogênio , Titânio , Peróxido de Hidrogênio/química , Concentração de Íons de Hidrogênio , Titânio/química , Ferro/química , Radical Hidroxila/química , Catálise , EletrodosRESUMO
INTRODUCTION: Osimertinib (AZD9291) is a third-generation epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor that has shown significant clinical benefits in patients with EGFR-sensitizing mutations or the EGFR T790M mutation. The homologous recombination (HR) pathway is crucial for repairing DNA double-strand breaks (DSBs). Rad51 plays a central role in HR, facilitating the search for homology and promoting DNA strand exchange between homologous DNA molecules. Rad51 is overexpressed in numerous types of cancer cells. B02, a specific small molecule inhibitor of Rad51, inhibits the DNA strand exchange activity of Rad51. Previous studies have indicated that B02 disrupted Rad51 foci formation in response to DNA damage and inhibited DSBs repair in human cells and sensitized them to chemotherapeutic drugs in vitro and in vivo. However, the potential therapeutic effects of combining osimertinib with a Rad51 inhibitor are not well understood. The aim of this study was to elucidate whether the downregulation of Rad51 expression and activity can enhance the osimertinib-induced cytotoxicity in non-small cell lung cancer (NSCLC) cells. METHODS: We used the MTS, trypan blue dye exclusion and colony-formation ability assay to determine whether osimertinib alone or in combination with B02 had cytotoxic effects on NSCLC cell lines. Real-time polymerase chain reaction was conducted to measure the amounts of Rad51 mRNA. The protein levels of phosphorylated AKT and Rad51 were determined by Western blot analysis. RESULTS: We found that osimertinib reduced Rad51 expression by inactivating AKT activity. Rad51 knockdown using small interfering RNA or AKT inactivation through the phosphatidylinositol 3-kinase inhibitor LY294002 or si-AKT RNA transfection enhanced the cytotoxic and growth inhibitory effects of osimertinib. In contrast, AKT-CA (a constitutively active form of AKT) vector-enforced expression could mitigate the cytotoxic and cell growth inhibitory effects of osimertinib. Furthermore, B02 significantly enhanced the cytotoxic and cell growth inhibitory effects of osimertinib in NSCLC cells. Compared to parental cells, the activation of AKT and Rad51 expression in osimertinib-resistant cells could not be significantly inhibited by osimertinib treatment. Moreover, the increased expression of Rad51 is associated with the resistance mechanism in osimertinib-resistant H1975 and A549 cells. CONCLUSION: Collectively, the downregulation of Rad51 expression and activity enhances the cytotoxic effect of osimertinib in human NSCLC cells.
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BACKGROUND: Patients with spinal cord injury have a relatively high risk for bladder cancer and often complicated with bladder cancer in advanced stages, and the degree of aggressiveness of malignancy is high. Most of the literature is based on disease clinical features while, our study reviews the clinical characteristics and molecular mechanisms of spinal cord injury patients with bladder cancer, so that it might help clinicians better recognize and manage these patients. METHOD: We searched PubMed, Web of Science and Embase, using retrieval type like ("Neurogenic Lower Urinary Tract Dysfunction" OR "Spinal cord injury" OR "Spinal Cord Trauma") AND ("bladder cancer" OR "bladder neoplasm" OR "bladder carcinoma" OR "Urinary Bladder Neoplasms" OR "Bladder Tumor"). In Web of Science, the retrieval type was searched as "Topic", and in PubMed and Embase, as "All Field". The methodological quality of eligible studies and their risk of bias were assessed using the Newcastle-Ottawa scale. This article is registered in PROSPERO with the CBD number: CRD42024508514. RESULT: In WOS, we searched 219 related papers, in PubMed, 122 and in Embase, 363. Thus, a total of 254 articles were included after passing the screening, within a time range between 1960 and 2023. A comprehensive analysis of the data showed that the mortality and incidence rates of bladder cancer in spinal cord injury patients were higher than that of the general population, and the most frequent pathological type was squamous cell carcinoma. In parallel to long-term urinary tract infection and indwelling catheterization, the role of molecules such as NO, MiR 1949 and Rb 1. was found to be crucial pathogenetically. CONCLUSION: This review highlights the risk of bladder cancer in SCI patients, comprehensively addressing the clinical characteristics and related molecular mechanisms. However, given that there are few studies on the molecular mechanisms of bladder cancer in spinal cord injury, further research is needed to expand the understanding of the disease.
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Traumatismos da Medula Espinal , Neoplasias da Bexiga Urinária , Traumatismos da Medula Espinal/complicações , Humanos , Neoplasias da Bexiga Urinária/complicaçõesRESUMO
Aphis spiraecola Patch is one of the most economically important tree fruit pests worldwide. The pyrethroid insecticide lambda-cyhalothrin is commonly used to control A. spiraecola. In this 2-year study, we quantified the resistance level of A. spiraecola to lambda-cyhalothrin in different regions of the Shaanxi province, China. The results showed that A. spiraecola had reached extremely high resistance levels with a 174-fold resistance ratio (RR) found in the Xunyi region. In addition, we compared the enzymatic activity and expression level of P450 genes among eight A. spiraecola populations. The P450 activity of A. spiraecola was significantly increased in five regions (Xunyi, Liquan, Fengxiang, Luochuan, and Xinping) compared to susceptible strain (SS). The expression levels of CYP6CY7, CYP6CY14, CYP6CY22, P4504C1-like, P4506a13, CYP4CZ1, CYP380C47, and CYP4CJ2 genes were significantly increased under lambda-cyhalothrin treatment and in the resistant field populations. A L1014F mutation in the sodium channel gene was found and the mutation rate was positively correlated with the LC50 of lambda-cyhalothrin. In conclusion, the levels of lambda-cyhalothrin resistance of A. spiraecola field populations were associated with P450s and L1014F mutations. Our combined findings provide evidence on the resistance mechanism of A. spiraecola to lambda-cyhalothrin and give a theoretical basis for rational and effective control of this pest species.
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Afídeos , Inseticidas , Piretrinas , Canais de Sódio Disparados por Voltagem , Animais , Afídeos/genética , Piretrinas/farmacologia , Nitrilas/farmacologia , Mutação , Canais de Sódio Disparados por Voltagem/genética , Expressão Gênica , Inseticidas/farmacologia , Resistência a Inseticidas/genéticaRESUMO
Immobilizing molecular catalysts on electro-conductive supports (for example, multi-walled carbon nanotubes, CNTs) represent a promising way to well-defined catalyst/support interfaces, which has shown appreciable performance for catalytic transformation. However, their full potential is far from achieved due to insufficient utilization of the intrinsic activity for each immobilized molecular catalyst, especially at loadings that should allow decent current densities. In the present work, we discover host-guest interaction between tetra-crown ether substituted cobalt phthalocyanine and metal ions, for example K+ ions, not only eliminate catalyst aggregation at immobilization procedures but also reinforce catalyst/support interactions by additional electrostatic attractions under operational conditions. Through simple dip-coating procedures, a successful single-molecular dispersion is achieved. Such a catalyst/electrode interface is stable and can selectively catalyze CO2-to-CO conversion (ï¼96%) with almost unchanged turnover frequency (TOF) at all loading conditions, which implies a full utilization of the intrinsic activity of supported molecular catalysts. Therefore, a simultaneous achievement of high TOF and high current density (TOF of 111 s-1 at 38 mA/cm2) is achieved, in an aqueous H-type electrolyzer at an overpotential of 570 mV.
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O-GlcNAcylation is a post-translational modification of protein in response to genetic variations or environmental factors, which is controlled by two highly conserved enzymes, i.e. O-GlcNAc transferase (OGT) and protein O-GlcNAcase (OGA). Protein O-GlcNAcylation mainly occurs in the cytoplasm, nucleus, and mitochondrion, and it is ubiquitously implicated in the development of cardiovascular disease (CVD). Alterations of O-GlcNAcylation could cause massive metabolic imbalance and affect cardiovascular function, but the role of O-GlcNAcylation in CVD remains controversial. That is, acutely increased O-GlcNAcylation is an adaptive heart response, which temporarily protects cardiac function. While it is harmful to cardiomyocytes if O-GlcNAcylation levels remain high in chronic conditions or in the long run. The underlying mechanisms include regulation of transcription, energy metabolism, and other signal transduction reactions induced by O-GlcNAcylation. In this review, we will focus on the interactions between protein O-GlcNAcylation and CVD, and discuss the potential molecular mechanisms that may be able to pave a new avenue for the treatment of cardiovascular events.
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Doenças Cardiovasculares , Humanos , Doenças Cardiovasculares/metabolismo , beta-N-Acetil-Hexosaminidases/genética , beta-N-Acetil-Hexosaminidases/metabolismo , Processamento de Proteína Pós-Traducional , Coração , Mitocôndrias/metabolismo , N-Acetilglucosaminiltransferases/genética , N-Acetilglucosaminiltransferases/metabolismoRESUMO
Horner Syndrome (HS) is characterized by symptoms of ipsilateral miosis, ptosis, enophthalmos, and facial anhidrosis, which is caused by the damaged oculosympathetic pathway. HS is rarely reported as postoperative complications of fine-needle aspiration (FNA). We report a case of HS triggered by Ultrasound-guided FNA during thyroid cancer management and conducted the literature review. A 31-year-old male with differentiated thyroid cancer underwent total thyroidectomy and regional lymph node dissection as well as radioactive iodine ablation, presented with persistently elevated tumor marker of thyroglobulin and suspicious left level IV and V cervical lymph nodes by neck ultrasound. Ultrasound-guided left cervical lymph nodes FNA for cellular diagnosis was performed, and typical manifestations of HS appeared immediately after the procedure. Subsequent ultrasound evaluation of the same area demonstrated a subtle strip of the hypo-echogenic area in the superior pole of the suspected level IV structure, suggesting sympathetic ganglia with the visible originating nerve fiber on the superior pole. All of the patient's symptoms of HS were resolved 2 months after the incidence. Cervical sympathetic ganglia can be similar in size, shape, and ultrasound characteristics to a malignant lymph node. Thorough ultrasound examination by directly comparing the potential ganglia with a typical malignant lymph node, and paying attention to any potential root fibers on the target is key to avoiding ganglia injury before the neck invasive procedures.
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Carcinoma Papilar , Síndrome de Horner , Neoplasias da Glândula Tireoide , Masculino , Humanos , Adulto , Neoplasias da Glândula Tireoide/complicações , Neoplasias da Glândula Tireoide/diagnóstico por imagem , Neoplasias da Glândula Tireoide/cirurgia , Biópsia por Agulha Fina/efeitos adversos , Síndrome de Horner/etiologia , Síndrome de Horner/patologia , Radioisótopos do Iodo , Carcinoma Papilar/metabolismo , Carcinoma Papilar/patologia , Carcinoma Papilar/cirurgia , Linfonodos/patologia , Ultrassonografia de IntervençãoRESUMO
Breast cancer is one of the most prevalent malignancies and the leading cause of cancer-associated mortality in China. Icaritin (ICT), a prenyl flavonoid derived from the Epimedium Genus, has been proven to inhibit the proliferation and stemness of breast cancer cells. Our previous study demonstrated that IC2, a derivative of ICT, could induce breast cancer cell apoptosis by Stearoyl-CoA desaturase 1 (SCD1) inhibition. The present study further investigated the mechanism of the inhibitory effects of IC2 on breast cancer cells in vitro and in vivo. Our results proved that IC2 could stimulate autophagy in breast cancer cells with the activation of adenosine monophosphate (AMP)-activated protein kinase (AMPK) signaling and mitogen-activated protein kinase (MAPK) signaling. Combination treatment of the AMPK inhibitor decreased IC2-induced autophagy while it markedly enhanced IC2-induced apoptosis. In common with IC2-induced apoptosis, SCD1 overexpression or the addition of exogenous oleic acid (OA) could also alleviate IC2-induced autophagy. In vivo assays additionally demonstrated that IC2 treatment markedly inhibited tumor growth in a mouse breast cancer xenograft model. Overall, our study was the first to demonstrate that IC2 induced cytoprotective autophagy by SCD1 inhibition in breast cancer cells and that the autophagy inhibitor markedly enhanced the anticancer activity of IC2. Therefore, IC2 was a potential candidate compound in combination therapy for breast cancer.
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Proteínas Quinases Ativadas por AMP , Neoplasias da Mama , Humanos , Animais , Camundongos , Feminino , Proteínas Quinases Ativadas por AMP/metabolismo , Apoptose , Flavonoides/farmacologia , Neoplasias da Mama/metabolismo , Autofagia , Linhagem Celular Tumoral , Estearoil-CoA Dessaturase/genéticaRESUMO
Sleep occupies one-third of a person's lifetime and is a necessary condition for maintaining physiological function and health. With the increase in social and economic pressures, the growing use of electronic devices and the accelerated aging process of the population, insufficient sleep and its hazards have drawn widespread attention from researchers in China and abroad. Sleep deprivation refers to a decrease in sleep or a severe lack of sleep due to various reasons. Previous studies have found that sleep deprivation can cause extensive damage to the body, including an increased incidence and mortality rate of neuropathic diseases in the brain, cardiovascular diseases, imbalances in the gut microbiota, and other multi-organ diseases. The mechanisms underlying the occurrence of multi-system and multi-organ diseases due to sleep deprivation mainly involve oxidative stress, inflammatory responses, and impaired immune function in the body. According to traditional Chinese medicine(TCM), sleep deprivation falls into the category of sleepiness, and long-term sleepiness leads to Yin-Yang imbalance, resulting in the consumption of Qi and damage to the five Zang-organs. The appropriate treatment should focus on tonifying deficiency, reinforcing healthy Qi, and harmonizing Yin and Yang. TCM is characterized by a wide variety and abundant resources, and it has minimal side effects and a broad range of applications. Numerous studies have shown that TCM drugs and prescriptions not only improve sleep but also have beneficial effects on liver nourishment, intelligence enhancement, and kidney tonification, effectively preventing and treating the body injury caused by sleep deprivation. Given the increasing prevalence of sleep deprivation and its significant impact on body health, this article reviewed sleep deprivation-mediated body injury and its mechanism, summarized and categorized TCM compound prescriptions and single drugs for preventing and treating body injury, with the aim of laying the foundation for researchers to develop effective drugs for preventing and treating body injury caused by sleep deprivation and providing references for further exploration of the molecular mechanisms underlying the body injury caused by sleep deprivation.
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Medicamentos de Ervas Chinesas , Medicina Tradicional Chinesa , Humanos , Privação do Sono/complicações , Privação do Sono/tratamento farmacológico , Sonolência , Yin-Yang , China , Medicamentos de Ervas Chinesas/uso terapêuticoRESUMO
As an emerging class of promising porous materials, the development of two-dimensional conductive metal organic frameworks (2D c-MOFs) is hampered by the few categories and tedious synthesis of the specific ligands. Herein, we developed a nonplanar hexahydroxyl-functionalized Salphen ligand (6OH-Salphen) through a facile two-step synthesis, which was further applied to construct layered 2D c-MOFs through in situ one pot synthesis based on the synergistic metal binding effect of the N2 O2 pocket of Salphen. Interestingly, the C2v -symmetry of ligand endows Cu-Salphen-MOF with periodically heterogeneous pore structures. Benefitting from the higher metal density and shorter in-plane metal-metal distance, Cu-Salphen-MOF showcased excellent NO2 sensing performance with good sensitivity, selectivity and reversibility. The current work opens up a new avenue to construct 2D c-MOF directly from nonplanar ligands, which greatly simplifies the synthesis and provides new possibilities for preparing different topological 2D c-MOF based functional materials.
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Food safety is a global problem, and methods to reliably and sensitivity detect contaminants could be transformative. Herein, we synthesized a novel Porphyrin NanoMoFs (NanoPCN-223(Fe)) with excellent dispersion and peroxidase-like activity. The Km value of NanoPCN-223(Fe) was 2.0 × 10-4 M toward the H2O2 substrate during the catalytic process. We use the NanoPCN-223(Fe) to construct an enhanced dispersion MOF-linked immunosorbent assay (Ed-MOFLISA) to sensitive detect AFB1 in milk. The optimized Ed-MOFLISA displayed a broad quantitative range from 0.05 to 10 ng/mL and a limit of detection of 0.003 ng/mL. Spiked peanut and soy milk recovery ranged from 91.22% to 97.63%. Intra-assay and inter-assay coefficient of variation values ranged from 0.78 to 3.85%, demonstrating the outstanding reproducibility and accuracy of Ed-MOFLISA. We applied the Ed-MOFLISA assay to test the milk samples, demonstrating its potential use for monitoring food quality.
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Aflatoxina B1 , Porfirinas , Aflatoxina B1/análise , Ensaio de Imunoadsorção Enzimática , Contaminação de Alimentos/análise , Peróxido de Hidrogênio , Imunoadsorventes , Limite de Detecção , Reprodutibilidade dos TestesRESUMO
Cyclodextrin (CD)-based polyrotaxanes (PR) are widely used to construct high-mechanical-performance materials because of the high degree of conformational freedom. However, strong hydrogen bonds between CDs greatly limit the application of CD-PR in the preparation of ductile neutral hydrogels. In this work, spiropyrane (SP) into α-CD-based PR is introduced to "visualize" the segment motion of the network in neutral water. The aggregation-induced cohesion and critical factors for the force transmission are disclosed. This system offers a new approach for the fundamental research for the complicated topologically cross-linked structures, which is important for the design of CD-PR-based biocompatible soft materials.
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Ciclodextrinas , Rotaxanos , Materiais Biocompatíveis/química , Ciclodextrinas/química , Hidrogéis/química , Rotaxanos/química , SolventesRESUMO
BACKGROUND: Endothelial dysfunction is common in diabetes. Apolipoprotein (apo) A-IV functions to antagonize inflammation and oxidative stress. The present study aimed to investigate the relationship between flow-mediated dilation (FMD) and serum apoA-IV level in type 2 diabetes mellitus (T2DM) patients. METHODS: A total of 84 T2DM patients with chest discomfort were enrolled in this study. Their baseline characteristics and clinical parameters were documented. Endothelial function of the participants was evaluated by examining FMD of brachial artery. The severity of coronary atherosclerosis was determined by quantitative coronary angiography. Serum apoA-IV levels were measured by ELISA. RESULTS: These diabetic patients were dichotomized into low FMD (n = 42) and high FMD (n = 42) groups. Serum apoA-IV levels were significantly higher in high FMD group than in low FMD group (29.96 ± 13.17 vs 17.69 ± 9.16 mg/dL, P < 0.001). Moreover, the patients were also categorized into three apoA-IV tertile groups. FMD was significantly different across three apoA-IV tertiles (P < 0.001). Serum apoA-IV levels were positively correlated to FMD (r = 0.469, P < 0.001). Logistic regression analysis was performed to determine risk factors for low FMD. apoA-IV levels together with the risk factor hsCRP remained significantly to be independent determinants of low FMD (P < 0.01). Linear regression analysis was performed, and apoA-IV levels together with total-to-HDL cholesterol ratio were independently correlated with FMD (P < 0.01). CONCLUSIONS: Serum apoA-IV levels are associated with FMD, suggesting that apoA-IV protects endothelial function in patients with T2DM.