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Numerous modern technologies are reliant on the low-phase noise and exquisite timing stability of microwave signals. Substantial progress has been made in the field of microwave photonics, whereby low-noise microwave signals are generated by the down-conversion of ultrastable optical references using a frequency comb1-3. Such systems, however, are constructed with bulk or fibre optics and are difficult to further reduce in size and power consumption. In this work we address this challenge by leveraging advances in integrated photonics to demonstrate low-noise microwave generation via two-point optical frequency division4,5. Narrow-linewidth self-injection-locked integrated lasers6,7 are stabilized to a miniature Fabry-Pérot cavity8, and the frequency gap between the lasers is divided with an efficient dark soliton frequency comb9. The stabilized output of the microcomb is photodetected to produce a microwave signal at 20 GHz with phase noise of -96 dBc Hz-1 at 100 Hz offset frequency that decreases to -135 dBc Hz-1 at 10 kHz offset-values that are unprecedented for an integrated photonic system. All photonic components can be heterogeneously integrated on a single chip, providing a significant advance for the application of photonics to high-precision navigation, communication and timing systems.
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Photonic integrated circuits are widely used in applications such as telecommunications and data-centre interconnects1-5. However, in optical systems such as microwave synthesizers6, optical gyroscopes7 and atomic clocks8, photonic integrated circuits are still considered inferior solutions despite their advantages in size, weight, power consumption and cost. Such high-precision and highly coherent applications favour ultralow-noise laser sources to be integrated with other photonic components in a compact and robustly aligned format-that is, on a single chip-for photonic integrated circuits to replace bulk optics and fibres. There are two major issues preventing the realization of such envisioned photonic integrated circuits: the high phase noise of semiconductor lasers and the difficulty of integrating optical isolators directly on-chip. Here we challenge this convention by leveraging three-dimensional integration that results in ultralow-noise lasers with isolator-free operation for silicon photonics. Through multiple monolithic and heterogeneous processing sequences, direct on-chip integration of III-V gain medium and ultralow-loss silicon nitride waveguides with optical loss around 0.5 decibels per metre are demonstrated. Consequently, the demonstrated photonic integrated circuit enters a regime that gives rise to ultralow-noise lasers and microwave synthesizers without the need for optical isolators, owing to the ultrahigh-quality-factor cavity. Such photonic integrated circuits also offer superior scalability for complex functionalities and volume production, as well as improved stability and reliability over time. The three-dimensional integration on ultralow-loss photonic integrated circuits thus marks a critical step towards complex systems and networks on silicon.
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Optical frequency combs have a wide range of applications in science and technology1. An important development for miniature and integrated comb systems is the formation of dissipative Kerr solitons in coherently pumped high-quality-factor optical microresonators2-9. Such soliton microcombs10 have been applied to spectroscopy11-13, the search for exoplanets14,15, optical frequency synthesis16, time keeping17 and other areas10. In addition, the recent integration of microresonators with lasers has revealed the viability of fully chip-based soliton microcombs18,19. However, the operation of microcombs requires complex startup and feedback protocols that necessitate difficult-to-integrate optical and electrical components, and microcombs operating at rates that are compatible with electronic circuits-as is required in nearly all comb systems-have not yet been integrated with pump lasers because of their high power requirements. Here we experimentally demonstrate and theoretically describe a turnkey operation regime for soliton microcombs co-integrated with a pump laser. We show the appearance of an operating point at which solitons are immediately generated by turning the pump laser on, thereby eliminating the need for photonic and electronic control circuitry. These features are combined with high-quality-factor Si3N4 resonators to provide microcombs with repetition frequencies as low as 15 gigahertz that are fully integrated into an industry standard (butterfly) package, thereby offering compelling advantages for high-volume production.
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The technology of liquid organic hydrogen carriers presents great promise for large-scale hydrogen storage. Nevertheless, the activation of inert C(sp3)-H bonds in hydrocarbon carriers poses formidable challenges, resulting in a sluggish dehydrogenation process and necessitating high operating temperatures. Here, we break the shackles of C-H bond activation under visible light irradiation by fabricating subnanometer Pt clusters on defective Ce-Zr solid solutions. We achieved an unprecedented hydrogen production rate of 2601 mmol gcat.-1 h-1 (turnover frequency >50,000 molH2 molPt-1 h-1) from cyclohexane, surpassing the most advanced thermo- and photocatalysts. By optimizing the temperature-dominated hydrogen transfer process, achievable by harnessing hitherto wasted infrared light in sunlight, an astonishing 56% apparent quantum efficiency and a 5.2% solar-to-hydrogen efficiency are attained at 353 K. Our research stands as one of the most effective photocatalytic processes to date, holding profound practical significance in the utilization of solar energy and the exploitation of alkanes.
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Organic photovoltaic (OPV) devices attain high performance with nonfullerene acceptors by utilizing the synergistic dual channels of charge generation that originate from excitations in both the donor and acceptor materials. However, the specific intermediate states that facilitate both channels are subject to debate. To address this issue, we employ time-resolved terahertz spectroscopy with improved sensitivity (ΔE/E < 10-6), enabling direct probing of charge generation dynamics in a prototypical PM6:Y6 bulk heterojunction system under one-sun-equivalent excitation density. Charge generation arising from donor excitations is characterized with a rise time of â¼9 ps, while that from acceptor excitations shows a rise time of â¼18 ps. Temperature-dependent measurements further reveal notably distinct activation energies for these two charge generation pathways. Additionally, the two channels of charge generation can be substantially manipulated by altering the ratio of bulk to interfaces. These findings strongly suggest the presence of two distinct intermediate states: interfacial and intramoiety excitations. These states are crucial in mediating the transfer of electrons and holes, driving charge generation within OPV devices.
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BACKGROUND: Information transmission between primary tumor cells and immunocytes or stromal cells in distal organs is a critical factor in the formation of pre-metastatic niche (PMN). Understanding this mechanism is essential for developing effective therapeutic strategy against tumor metastasis. Our study aims to prove the hypothesis that circ-0034880-enriched tumor-derived extracellular vesicles (TEVs) mediate the formation of PMN and colorectal cancer liver metastasis (CRLM), and targeting circ-0034880-enriched TEVs might be an effective therapeutic strategy against PMN formation and CRLM. METHODS: We utilized qPCR and FISH to measure circRNAs expression levels in human CRC plasma, primary CRC tissues, and liver metastatic tissues. Additionally, we employed immunofluorescence, RNA sequencing, and in vivo experiments to assess the effect mechanism of circ-0034880-enriched TEVs on PMN formation and CRC metastasis. DARTS, CETSA and computational docking modeling were applied to explore the pharmacological effects of Ginsenoside Rb1 in impeding PMN formation. RESULTS: We found that circ-0034880 was highly enriched in plasma extracellular vesicles (EVs) derived from CRC patients and closely associated with CRLM. Functionally, circ-0034880-enriched TEVs entered the liver tissues and were absorbed by macrophages in the liver through bloodstream. Mechanically, TEVs-released circ-0034880 enhanced the activation of SPP1highCD206+ pro-tumor macrophages, reshaping the metastasis-supportive host stromal microenvironment and promoting overt metastasis. Importantly, our mechanistic findings led us to discover that the natural product Ginsenoside Rb1 impeded the activation of SPP1highCD206+ pro-tumor macrophages by reducing circ-0034880 biogenesis, thereby suppressing PMN formation and inhibiting CRLM. CONCLUSIONS: Circ-0034880-enriched TEVs facilitate strong interaction between primary tumor cells and SPP1highCD206+ pro-tumor macrophages, promoting PMN formation and CRLM. These findings suggest the potential of using Ginsenoside Rb1 as an alternative therapeutic agent to reshape PMN formation and prevent CRLM.
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Neoplasias Colorretais , Vesículas Extracelulares , Neoplasias Hepáticas , Osteopontina , RNA Circular , Humanos , Neoplasias Colorretais/patologia , Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/genética , Vesículas Extracelulares/metabolismo , Neoplasias Hepáticas/secundário , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/patologia , Camundongos , Animais , RNA Circular/genética , Osteopontina/metabolismo , Osteopontina/genética , Linhagem Celular Tumoral , Microambiente Tumoral , Masculino , Feminino , Macrófagos Associados a Tumor/metabolismo , Macrófagos Associados a Tumor/efeitos dos fármacos , Macrófagos Associados a Tumor/imunologia , Macrófagos/metabolismo , Macrófagos/efeitos dos fármacos , Macrófagos/imunologia , Ensaios Antitumorais Modelo de Xenoenxerto , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacosRESUMO
Background Cerebellar mutism syndrome (CMS), a complication following medulloblastoma surgery, has been linked to dentato-thalamo-cortical tract (DTCT) injury; the association of the degree of DTCT injury with severity of CMS-related symptoms has not been investigated. Purpose To investigate the association between severity of CMS-related symptoms and degree and patterns of DTCT injury with use of diffusion tensor imaging (DTI), and if laterality of injury influences neurologic symptoms. Materials and Methods This retrospective case-control study used prospectively collected clinical and DTI data on patients with medulloblastoma enrolled in a clinical trial (between July 2016 and February 2020) and healthy controls (between April and November 2017), matched with the age range of the participants with medulloblastoma. CMS was divided into types 1 (CMS1) and 2 (CMS2). Multivariable logistic regression was used to investigate the relationship between CMS likelihood and DTCT injury. Results Overall, 82 participants with medulloblastoma (mean age, 11.0 years ± 5.2 [SD]; 53 male) and 35 healthy controls (mean age, 18.0 years ± 3.06; 18 female) were included. In participants with medulloblastoma, DTCT was absent bilaterally (AB), absent on the right side (AR), absent on the left side (AL), or present bilaterally (PB), while it was PB in all healthy controls. Odds of having CMS were associated with higher degree of DTCT damage (AB, odds ratio = 272.7 [95% CI: 269.68, 275.75; P < .001]; AR, odds ratio = 14.40 [95% CI: 2.84, 101.48; P < .001]; and AL, odds ratio = 8.55 [95% CI: 1.15, 74.14; P < .001). Left (coefficient = -0.07, χ2 = 12.4, P < .001) and right (coefficient = -0.15, χ2 = 33.82, P < .001) DTCT volumes were negatively associated with the odds of CMS. More participants with medulloblastoma with AB showed CMS1; unilateral DTCT absence prevailed in CMS2. Lower DTCT volumes correlated with more severe ataxia. Unilateral DTCT injury caused ipsilateral dysmetria; AB caused symmetric dysmetria. PB indicated better neurologic outcome. Conclusion The severity of CMS-associated mutism, ataxia, and dysmetria was associated with DTCT damage severity. DTCT damage patterns differed between CMS1 and CMS2. © RSNA, 2024 Supplemental material is available for this article. See also the editorial by Dorigatti Soldatelli and Ertl-Wagner in this issue.
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Neoplasias Cerebelares , Imagem de Tensor de Difusão , Meduloblastoma , Mutismo , Complicações Pós-Operatórias , Humanos , Meduloblastoma/cirurgia , Meduloblastoma/diagnóstico por imagem , Masculino , Feminino , Mutismo/etiologia , Mutismo/diagnóstico por imagem , Imagem de Tensor de Difusão/métodos , Estudos Retrospectivos , Criança , Estudos de Casos e Controles , Adolescente , Neoplasias Cerebelares/diagnóstico por imagem , Neoplasias Cerebelares/cirurgia , Complicações Pós-Operatórias/diagnóstico por imagem , Vias Neurais/diagnóstico por imagem , Tálamo/diagnóstico por imagemRESUMO
UBXD family (UBXDF), a group of proteins containing ubiquitin regulatory X (UBX) domains, play a crucial role in the imbalance of proliferation and apoptotic in cancer. In this study, we summarised bioinformatics proof on multi-omics databases and literature on UBXDF's effects on cancer. Bioinformatics analysis revealed that Fas-associated factor 1 (FAF1) has the largest number of gene alterations in the UBXD family and has been linked to survival and cancer progression in many cancers. UBXDF may affect tumour microenvironment (TME) and drugtherapy and should be investigated in the future. We also summarised the experimental evidence of the mechanism of UBXDF in cancer, both in vitro and in vivo, as well as its application in clinical and targeted drugs. We compared bioinformatics and literature to provide a multi-omics insight into UBXDF in cancers, review proof and mechanism of UBXDF effects on cancers, and prospect future research directions in-depth. We hope that this paper will be helpful for direct cancer-related UBXDF studies.
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Neoplasias , Ubiquitina , Humanos , Ubiquitina/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Proteínas Reguladoras de Apoptose/metabolismo , Fatores de Transcrição/metabolismo , Neoplasias/genética , Neoplasias/terapia , Biologia Computacional , Microambiente TumoralRESUMO
We report the picosecond spin current generation from the interface between a heavy metal and a vicinal antiferromagnet insulator Cr_{2}O_{3} by laser pulses at room temperature and zero magnetic field. It is converted into a detectable terahertz emission in the heavy metal via the inverse spin Hall effect. The vicinal interfaces are apparently the source of the picosecond spin current, as evidenced by the proportional terahertz signals to the vicinal angle. We attribute the origin of the spin current to the transient magnetic moment generated by an interfacial nonlinear magnetic-dipole difference-frequency generation. We propose a model based on the in-plane inversion symmetry breaking to quantitatively explain the terahertz intensity with respect to the angles of the laser polarization and the film azimuth. Our work opens new opportunities in antiferromagnetic and ultrafast spintronics by considering symmetry breaking.
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The kinesin-5 family member, Eg5, plays very important role in the mitosis. As a mitotic protein, Eg5 is the target of various mitotic inhibitors. There are two targeting pockets in the motor domain of Eg5, which locates in the α2/L5/α3 region and the α4/α6 region respectively. We investigated the interactions between the different inhibitors and the two binding pockets of Eg5 by using all-atom molecular dynamics method. Combined the conformational analysis with the free-energy calculation, the binding patterns of inhibitors to the two binding pockets are shown. The α2/L5/α3 pocket can be divided into 4 regions. The structures and binding conformations of inhibitors in region 1 and 2 are highly conserved. The shape of α4/α6 pocket is alterable. The space of this pocket in ADP-binding state of Eg5 is larger than that in ADP·Pi-binding state due to the limitation of a hydrogen bond formed in the ADP·Pi-binding state. The results of this investigation provide the structural basis of the inhibitor-Eg5 interaction and offer a reference for the Eg5-targeted drug design.
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Cinesinas , Simulação de Dinâmica Molecular , Ligação Proteica , Cinesinas/antagonistas & inibidores , Cinesinas/química , Cinesinas/metabolismo , Sítios de Ligação , Humanos , Difosfato de Adenosina/metabolismo , Difosfato de Adenosina/química , Ligação de HidrogênioRESUMO
BACKGROUND: Metastasis, the leading cause of renal cell carcinoma (RCC) mortality, involves cancer cells resisting anoikis and invading. Until now, the role of the matrix metalloproteinase (MMP)-related enzyme, A disintegrin and metalloprotease with thrombospondin motifs 1 (ADAMTS1), in RCC anoikis regulation remains unclear. METHODS: The clinical significance of ADAMTS1 and its associated molecules in patients with RCC was investigated using data from the Gene Expression Omnibus (GEO) and TCGA datasets. Human phosphoreceptor tyrosine kinase (RTK) array, luciferase reporter assays, immunoprecipitation (IP) assays, western blotting, and real-time reverse-transcription quantitative polymerase chain reaction (RT-qPCR) were used to elucidate the underlying mechanisms of ADAMTS1. Functional assays, including anoikis resistance assays, invasion assays, and a Zebrafish xenotransplantation model, were conducted to assess the roles of ADAMTS1 in conferring resistance to anoikis in RCC. RESULTS: This study found elevated ADAMTS1 transcripts in RCC tissues that were correlated with a poor prognosis. ADAMTS1 manipulation significantly affected cell anoikis through the mitochondrial pathway in RCC cells. Human receptor tyrosine kinase (RTK) array screening identified that epidermal growth factor receptor (EGFR) activation was responsible for ADAMTS1-induced anoikis resistance and invasion. Further investigations revealed that enzymatically active ADAMTS1-induced versican V1 (VCAN V1) proteolysis led to EGFR transactivation, which in turn, through positive feedback, regulated ADAMTS1. Additionally, ADAMTS1 can form a complex with p53 to influence EGFR signaling. In vivo, VCAN or EGFR knockdown reversed ADAMTS1-induced prometastatic characteristics of RCC. A clinical analysis revealed a positive correlation between ADAMTS1 and VCAN or the EGFR and patients with RCC with high ADAMTS1 and VCAN expression had the worst prognoses. CONCLUSIONS: Our results collectively uncover a novel cyclic axis involving ADAMTS1-VCAN-EGFR, which significantly contributes to RCC invasion and resistance to anoikis, thus presenting a promising therapeutic target for RCC metastasis.
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Proteína ADAMTS1 , Anoikis , Carcinoma de Células Renais , Receptores ErbB , Neoplasias Renais , Transdução de Sinais , Versicanas , Animais , Humanos , Proteína ADAMTS1/metabolismo , Proteína ADAMTS1/genética , Anoikis/genética , Carcinoma de Células Renais/genética , Carcinoma de Células Renais/metabolismo , Carcinoma de Células Renais/patologia , Linhagem Celular Tumoral , Receptores ErbB/metabolismo , Receptores ErbB/genética , Regulação Neoplásica da Expressão Gênica , Neoplasias Renais/genética , Neoplasias Renais/patologia , Neoplasias Renais/metabolismo , Invasividade Neoplásica , Prognóstico , Versicanas/metabolismo , Versicanas/genética , Peixe-ZebraRESUMO
Microlasers in near-degenerate supermodes lay the cornerstone for studies of non-Hermitian physics, novel light sources, and advanced sensors. Recent experiments of the stimulated scattering in supermode microcavities reported beating phenomena, interpreted as dual-mode lasing, which, however, contradicts their single-mode nature due to the clamped pump field. Here, we investigate the supermode Raman laser in a whispering-gallery microcavity and demonstrate experimentally its single-mode lasing behavior with a side-mode suppression ratio (SMSR) up to 37 dB, despite the emergence of near-degenerate supermodes by the backscattering between counterpropagating waves. Moreover, the beating signal is recognized as the transient interference during the switching process between the two supermode lasers. Self-injection is exploited to manipulate the lasing supermodes, where the SMSR is further improved by 15 dB and the laser linewidth is below 100 Hz.
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OBJECTIVE: To develop a multi-instance learning (MIL) based artificial intelligence (AI)-assisted diagnosis models by using laryngoscopic images to differentiate benign and malignant vocal fold leukoplakia (VFL). METHODS: The AI system was developed, trained and validated on 5362 images of 551 patients from three hospitals. Automated regions of interest (ROI) segmentation algorithm was utilized to construct image-level features. MIL was used to fusion image level results to patient level features, then the extracted features were modeled by seven machine learning algorithms. Finally, we evaluated the image level and patient level results. Additionally, 50 videos of VFL were prospectively gathered to assess the system's real-time diagnostic capabilities. A human-machine comparison database was also constructed to compare the diagnostic performance of otolaryngologists with and without AI assistance. RESULTS: In internal and external validation sets, the maximum area under the curve (AUC) for image level segmentation models was 0.775 (95 % CI 0.740-0.811) and 0.720 (95 % CI 0.684-0.756), respectively. Utilizing a MIL-based fusion strategy, the AUC at the patient level increased to 0.869 (95 % CI 0.798-0.940) and 0.851 (95 % CI 0.756-0.945). For real-time video diagnosis, the maximum AUC at the patient level reached 0.850 (95 % CI, 0.743-0.957). With AI assistance, the AUC improved from 0.720 (95 % CI 0.682-0.755) to 0.808 (95 % CI 0.775-0.839) for senior otolaryngologists and from 0.647 (95 % CI 0.608-0.686) to 0.807 (95 % CI 0.773-0.837) for junior otolaryngologists. CONCLUSIONS: The MIL based AI-assisted diagnosis system can significantly improve the diagnostic performance of otolaryngologists for VFL and help to make proper clinical decisions.
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Inteligência Artificial , Laringoscopia , Leucoplasia , Prega Vocal , Humanos , Prega Vocal/diagnóstico por imagem , Prega Vocal/patologia , Laringoscopia/métodos , Masculino , Leucoplasia/diagnóstico , Leucoplasia/patologia , Feminino , Pessoa de Meia-Idade , Idoso , Diagnóstico por Computador/métodos , Aprendizado de Máquina , Diagnóstico Diferencial , Adulto , Algoritmos , Neoplasias Laríngeas/diagnóstico , Neoplasias Laríngeas/patologia , Neoplasias Laríngeas/diagnóstico por imagemRESUMO
BACKGROUND: Prophylactic intraoperative drains have been shown not superior for patients underwent intestinal surgery. However, for patients with Crohn's disease (CD), this needs further exploration. METHODS: In this pilot study, CD patients were randomly assigned to drain (n = 50) and no-drain (n = 50) groups. The primary endpoint was the rate of postoperative prolonged ileus (PPOI). The secondary endpoints were postoperative abdominal ascites, postoperative systemic inflammatory response syndrome (SIRS) and C-reactive protein (CRP) levels. RESULTS: The incidences of PPOI and postoperative abdominal ascites were significantly lower in the drain group (12% vs 44%; 0% vs 24%, both P < .05). Postoperative SIRS incidence and CRP levels were significantly increased in the no-drain group [36% vs 10%; 54.9 vs 34.3 mg/L, both P < .05]. In multivariate analysis, prophylactic drainage was the independent protective factor for PPOI and postoperative LOS. CONCLUSIONS: Prophylactic drainage may be associated with improved clinical outcomes in CD patients.
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Ascite , Doença de Crohn , Humanos , Ascite/complicações , Doença de Crohn/cirurgia , Doença de Crohn/complicações , Projetos Piloto , Complicações Pós-Operatórias/prevenção & controle , Complicações Pós-Operatórias/etiologia , Drenagem , Síndrome de Resposta Inflamatória Sistêmica/complicaçõesRESUMO
Macrocycles composed of diverse aromatic or nonaromatic structures, such as cyclodextrins (CDs), calixarenes (CAs), cucurbiturils (CBs), and pillararenes (PAs), have garnered significant attention due to their inherent advantages of possessing cavity structures, unique functional groups, and facile modification. Due to these distinctive features enabling them to facilitate ion insertion and extraction, form crosslinked porous structures, offer multiple redox-active sites, and engage in host-guest interactions, macrocycles have made huge contributions to electrochemical energy storage and conversion (EES/EEC). Here, we have summarized the recent advancements and challenges in the utilization of CDs, CAs, CBs, and PAs as well as other novel macrocycles applied in EES/EEC devices. The molecular structure, properties, and modification strategies are discussed along with the corresponding energy density, specific capacity, and cycling life properties in detail. Finally, crucial limitations and future research directions pertaining to these macrocycles in electrochemical energy storage and conversion are addressed. It is hoped that this review is able to inspire interest and enthusiasm in researchers to investigate macrocycles and promote their applications in EES/EEC.
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CONTEXT: Diabetic nephropathy (DN) is a major complication of diabetes mellitus and is the leading cause of kidney disease in patients undergoing renal replacement therapy. DN is associated with an increased risk of death in patients with diabetes. Conventional therapy for DN includes intensive control of blood glucose level and blood pressure and renin-angiotensin system blockade. However, this approach has limited treatment effects on DN. Therefore, identifying novel drugs to delay the progression of DN is urgently needed. Proanthocyanidin (PA) has been shown to exert potentially beneficial effects on DN. However, the protective mechanism and efficacy are yet to be elucidated. OBJECTIVE: This study evaluates the efficacy and potential mechanisms of PA in animal models of DN. METHODS: Preclinical studies were searched from Chinese National Knowledge Infrastructure, PubMed, Web of Science, Embase, and Google Scholar databases, with the search deadline of August 2023. Keywords ('diabetic nephropathies', 'nephropathies, diabetic', 'diabetic kidney diseases', 'proanthocyanidin', 'anthocyanidin polymers', 'procyanidins', 'animal*', 'rat', and 'mice') were used to search the databases. RevMan 5.3 was used for statistical analysis. RESULTS: A total of 22 studies involving 538 animals were included in this analysis. The pooled results indicated that PA therapy significantly improved kidney function and reduced proteinuria and blood glucose levels. The protective mechanism of PA was associated with anti-inflammatory, antioxidant, antifibrotic, and antiapoptotic effects; inhibition of endoplasmic reticulum stress; and alleviation of mitochondrial dysfunction and dyslipidemia. CONCLUSION: These findings suggest that PA alleviates DN by mediating multiple targets and pathways.
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Nefropatias Diabéticas , Modelos Animais de Doenças , Proantocianidinas , Proantocianidinas/farmacologia , Animais , Nefropatias Diabéticas/tratamento farmacológico , Nefropatias Diabéticas/prevenção & controle , Camundongos , Ratos , HumanosRESUMO
This study aims to investigate whether baicalin induces ferroptosis in HepG2 cells and decipher the underlying mechanisms based on network pharmacology and cell experiments. HepG2 cells were cultured in vitro and the cell viability was detected by the cell counting kit-8(CCK-8). The transcriptome data of hepatocellular carcinoma were obtained from the Cancer Genome Atlas(TCGA), and the ferroptosis gene data from FerrDb V2. The DEG2 package was used to screen the differentially expressed genes(DEGs), and the common genes between DEGs and ferroptosis genes were selected as the target genes that mediate ferroptosis to regulate hepatocellular carcinoma progression. The functions and structures of the target genes were analyzed by Gene Ontology(GO) functional annotation and Kyoto Encyclopedia of Genes and Genomes(KEGG) pathway enrichment with the thresholds of P<0.05 and |log_2(fold change)|>0.5. DCFH-DA probe was used to detect the changes in the levels of cellular reactive oxygen species(ROS) in each group. The reduced glutathione(GSH) assay kit was used to measure the cellular GSH level, and Fe~(2+) assay kit to determine the Fe~(2+) level. Real-time quantitative PCR(RT-PCR) was employed to measure the mRNA levels of glutathione peroxidase 4(GPX4) and solute carrier family 7 member 11(SLC7A11) in each group. Western blot was employed to determine the protein levels of GPX4, SLC7A11, phosphatidylinositol 3-kinase(PI3K), p-PI3K, protein kinase B(Akt), p-Akt, forkhead box protein O3a(FoxO3a), and p-FoxO3a in each group. The results showed that treatment with 200 µmol·L~(-1) baicalin for 48 h significantly inhibited the viability of HepG2 cells. Ferroptosis in hepatocellular carcinoma could be regulated via the PI3K/Akt signaling pathway. The cell experiments showed that baicalin down-regulated the expression of SLC7A11 and GPX4, lowered the GSH level, and increased ROS accumulation and Fe~(2+) production in HepG2 cells. However, ferrostatin-1, an ferroptosis inhibitor, reduced baicalin-induced ROS accumulation, up-regulated the expression of SLC7A11 and GPX4, elevated the GSH level, and decreased PI3K, Akt, and FoxO3a phosphorylation. In summary, baicalin can induce ferroptosis in HepG2 cells by inhibiting the ROS-mediated PI3K/Akt/FoxO3a pathway.
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Carcinoma Hepatocelular , Ferroptose , Flavonoides , Neoplasias Hepáticas , Humanos , Proteínas Proto-Oncogênicas c-akt/genética , Fosfatidilinositol 3-Quinases/genética , Espécies Reativas de Oxigênio , Células Hep G2 , Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/genética , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/genética , Transdução de SinaisRESUMO
Selective producing ethanol from CO2 electroreduction is highly demanded, yet the competing ethylene generation route is commonly more thermodynamically preferred. Herein, we reported an efficient CO2-to-ethanol conversion (53.5 % faradaic efficiency at -0.75â V versus reversible hydrogen electrode (vs. RHE)) over an oxide-derived nanocubic catalyst featured with abundant "embossment-like" structured grain-boundaries. The catalyst also attains a 23.2 % energy efficiency to ethanol within a flow cell reactor. In situ spectroscopy and electrochemical analysis identified that these dualphase Cu(I) and Cu(0) sites stabilized by grain-boundaries are very robust over the operating potential window, which maintains a high concentration of co-adsorbed *CO and hydroxyl (*OH) species. Theoretical calculations revealed that the presence of *OHad not only promote the easier dimerization of *CO to form *OCCO (ΔG~0.20â eV) at low overpotentials but also preferentially favor the key *CHCOH intermediate hydrogenation to *CHCHOH (ethanol pathway) while suppressing its dehydration to *CCH (ethylene pathway), which is believed to determine the remarkable ethanol selectivity. Such imperative intermediates associated with the bifurcation pathway were directly distinguished by isotope labelling in situ infrared spectroscopy. Our work promotes the understanding of bifurcating mechanism of CO2ER-to-hydrocarbons more deeply, providing a feasible strategy for the design of efficient ethanol-targeted catalysts.
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Although activation of astrocytes is critical in developing neuropathic pain (NP) following nerve injury, the underlying mechanisms of NP and therapeutic management for NP are still vague. Importantly, the decreases in the levels of astrocytic glutamate transporter-1 (GLT-1) in the spinal dorsal horn result in enhanced excitatory transmission and cause persistent pain. P2Y1 purinergic receptor (P2Y1R) has been shown to enhance many inflammatory processes. The up-regulated expression of astrocytic P2Y1R is crucial to participate in pain transduction under conditions of nerve injury and peripheral inflammation considering that P2Y1R is potentially involved in glutamate release and synaptic transmission. This study indicates that the expression of P2Y1R in the spinal cord was increased accompanied by the activation of A1 phenotype astrocytes in the rat model of spinal nerve ligation (SNL). Astrocyte-specific knockdown of P2Y1R alleviated SNL-induced nociceptive responses and mitigated A1 reactive astrocytes, which subsequently increased GLT-1 expression. Conversely, in naïve rats, P2Y1R over-expression induced a canonical NP-like phenotype and spontaneous hypernociceptive responses and increased the concentration of glutamate in the spinal dorsal horn. Besides, our in vitro data showed that the proinflammatory cytokine tumour necrosis factor-alpha contributes to A1/A2 astrocyte reactivity and Ca2+ -dependent release of glutamate. Conclusively, our results provide novel insights that as a significant regulator of astrocytic A1/A2 polarization and neuroinflammation, P2Y1R may represent a potential target for the treatment of SNL-induced NP.
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BACKGROUND: Surgery is the primary treatment for locally advanced differentiated thyroid cancer (DTC). However, some locally advanced patients are not candidates for R0/1 resection. There is limited evidence of neoadjuvant treatment in locally advanced DTC. Surufatinib targets multiple kinases, which is efficient, tolerable, and safe in patients with radioiodine-refractory DTC. In addition, surufatinib plus toripalimab (an anti-PD-1 antibody) showed encouraging antitumor activity in advanced solid tumors. This study was designed to evaluate the efficacy and safety of surufatinib plus toripalimab in locally advanced DTC in the neoadjuvant setting. METHODS: In this single-arm, phase II study, patients with pathologically confirmed unresectable or borderline resectable DTC were eligible and received a combination of 250 mg of surufatinib (orally daily) with 240 mg of toripalimab (intravenous, every 3 weeks). Treatment continued until satisfied for curative surgery, disease progression, withdrawal of consent, unacceptable toxicity, or investigator decision. Primary endpoint was objective response rate (ORR). Secondary endpoints included R0/1 resection rate, adverse events (AEs), etc. RESULTS: Ten patients were enrolled and received at least 4 cycles of treatment. The ORR was 60%. Nine patients received R0/1 resections after neoadjuvant treatment. The median best percentage change in the sum of the target lesion diameter was 32%. Most adverse events (AEs) were grade 1 or 2. CONCLUSIONS: Surufatinib in combination with toripalimab as neoadjuvant therapy for locally advanced DTC was feasible, and the majority of patients achieved R0/1 resection. It represents a new option for locally advanced DTC and needs further investigation.