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1.
Nature ; 588(7839): 693-698, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33177715

RESUMO

Despite its success in achieving the long-term survival of 10-30% of treated individuals, immune therapy is still ineffective for most patients with cancer1,2. Many efforts are therefore underway to identify new approaches that enhance such immune 'checkpoint' therapy3-5 (so called because its aim is to block proteins that inhibit checkpoint signalling pathways in T cells, thereby freeing those immune cells to target cancer cells). Here we show that inhibiting PCSK9-a key protein in the regulation of cholesterol metabolism6-8-can boost the response of tumours to immune checkpoint therapy, through a mechanism that is independent of PCSK9's cholesterol-regulating functions. Deleting the PCSK9 gene in mouse cancer cells substantially attenuates or prevents their growth in mice in a manner that depends on cytotoxic T cells. It also enhances the efficacy of immune therapy that is targeted at the checkpoint protein PD1. Furthermore, clinically approved PCSK9-neutralizing antibodies synergize with anti-PD1 therapy in suppressing tumour growth in mouse models of cancer. Inhibiting PCSK9-either through genetic deletion or using PCSK9 antibodies-increases the expression of major histocompatibility protein class I (MHC I) proteins on the tumour cell surface, promoting robust intratumoral infiltration of cytotoxic T cells. Mechanistically, we find that PCSK9 can disrupt the recycling of MHC I to the cell surface by associating with it physically and promoting its relocation and degradation in the lysosome. Together, these results suggest that inhibiting PCSK9 is a promising way to enhance immune checkpoint therapy for cancer.


Assuntos
Inibidores de Checkpoint Imunológico/farmacologia , Inibidores de Checkpoint Imunológico/uso terapêutico , Imunoterapia/métodos , Neoplasias/tratamento farmacológico , Neoplasias/imunologia , Inibidores de PCSK9 , Receptor de Morte Celular Programada 1/antagonistas & inibidores , Animais , Anticorpos Neutralizantes/imunologia , Anticorpos Neutralizantes/farmacologia , Anticorpos Neutralizantes/uso terapêutico , Linhagem Celular Tumoral , Modelos Animais de Doenças , Feminino , Antígenos de Histocompatibilidade Classe I/imunologia , Antígenos de Histocompatibilidade Classe I/metabolismo , Humanos , Lisossomos/metabolismo , Camundongos , Neoplasias/metabolismo , Neoplasias/patologia , Pró-Proteína Convertase 9/deficiência , Pró-Proteína Convertase 9/genética , Pró-Proteína Convertase 9/imunologia , Linfócitos T Citotóxicos/citologia , Linfócitos T Citotóxicos/imunologia , Ensaios Antitumorais Modelo de Xenoenxerto
2.
J Am Chem Soc ; 146(13): 9335-9346, 2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38501695

RESUMO

Controlling product selectivity in successive reactions of the same type is challenging owing to the comparable thermodynamic and kinetic properties of the reactions involved. Here, the synergistic interaction of the two phosphoryl groups in bisphosphine dioxides (BPDOs) with a bromo-phosphonium cation was studied experimentally to provide a practical tool for substrate-catalyst recognition. As the eventual result, we have developed a phosphonium-catalyzed monoreduction of chiral BPDOs to access an array of synthetically useful bisphosphine monoxides (BPMOs) with axial, spiro, and planar chirality, which are otherwise challenging to synthesize before. The reaction features excellent selectivity and impressive reactivity. It proceeds under mild conditions, avoiding the use of superstoichiometric amounts of additives and metal catalysts to simplify the synthetic procedure. The accessibility and scalability of the reaction allowed for the rapid construction of a ligand library for optimization of asymmetric Heck-type cyclization, laying the foundation for a broad range of applications of chiral BPMOs in catalysis.

3.
Small ; 20(29): e2309863, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38368256

RESUMO

Research on flexible thermoelectric (TE) materials has typically focused on conducting polymers and conducting polymer-based composites. However, achieving TE properties comparable in magnitude to those exhibited by their inorganic counterparts remains a formidable challenge. This study focuses on the synthesis of silver selenide (Ag2Se) nanomaterials using solvothermal methods and demonstrates a significant enhancement in their TE properties through the synergistic dual doping of sulfur and copper. Flexible TE thin films demonstrating excellent flexibility are successfully fabricated using vacuum filtration and hot-pressing techniques. The resulting thin films also exhibited outstanding TE performance, with a high Seebeck coefficient (S = -138.5 µV K-1) and electrical conductivity (σ = 1.19 × 105 S m-1). The record power factor of 2296.8 µW m-1 K-2 at room temperature is primarily attributed to enhanced carrier transport and interfacial energy filtration effects in the composite material. Capitalizing on these excellent TE properties, the maximum power output of flexible TE devices reached 1.13 µW with a temperature difference of 28.6 K. This study demonstrates the potential of Ag2Se-based TE materials for flexible and efficient energy-harvesting applications.

4.
Opt Lett ; 49(11): 2886-2889, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38824284

RESUMO

Light field (LF) imaging has gained significant attention in the field of computational imaging due to its unique capability to capture both spatial and angular information of a scene. In recent years, super-resolution (SR) techniques based on deep learning have shown considerable advantages in enhancing LF image resolution. However, the inherent challenges of obtaining rich structural information and reconstructing complex texture details persist, particularly in scenarios where spatial and angular information are intricately interwoven. This Letter introduces a novel, to the best of our knowledge, approach for Disentangling LF Image SR Network (DLISN) by leveraging the synergy of dual learning and Fourier channel attention (FCA) mechanisms. Dual learning strategies are employed to enhance reconstruction results, addressing limitations in model generalization caused by the difficulty in acquiring paired datasets in real-world LF scenarios. The integration of FCA facilitates the extraction of high-frequency information associated with different structures, contributing to improved spatial resolution. Experimental results consistently demonstrate superior performance in enhancing the resolution of LF images.

5.
Chemistry ; 30(33): e202400995, 2024 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-38600034

RESUMO

Introduction of the trifluoromethyl (CF3) group into organic compounds has garnered substantial interest because of its significant role in pharmaceuticals and agrochemicals. Here, we report a hydroxylamine-mediated radical process for C(sp2)-H trifluoromethylation of terminal alkenes. The reaction shows good reactivity, impressive E/Z selectivity (up to >20 : 1), and broad functional group compatibility. Expansion of this approach to perfluoroalkylation and late-stage trifluoromethylation of bioactive molecules demonstrates its promising application potential. Mechanistic studies suggest that the reaction follows a radical addition and subsequent elimination pathway.

6.
BMC Cancer ; 24(1): 156, 2024 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-38291366

RESUMO

BACKGROUND: Lactate dehydrogenase (LDHs) is an enzyme involved in anaerobic glycolysis, including LDHA, LDHB, LDHC and LDHD. Given the regulatory role in the biological progression of certain tumors, we analyzed the role of LDHs in pan-cancers. METHODS: Cox regression, Kaplan-Meier curves, Receiver Operating Characteristic (ROC) curves, and correlation of clinical indicators in tumor patients were used to assess the prognostic significance of LDHs in pan-cancer. The TCGA, HPA, TIMER, UALCAN, TISIDB, and Cellminer databases were used to investigate the correlation between the expression of LDHs and immune subtypes, immune checkpoint genes, methylation levels, tumor mutational load, microsatellite instability, tumor-infiltrating immune cells and drug sensitivity. The cBioPortal database was also used to identify genomic abnormalities of LDHs in pan-cancer. A comprehensive assessment of the biological functions of LDHs was performed using GSEA. In vitro, HepG2 and Huh7 cells were transfected with LDHD siRNA and GFP-LDHD, the proliferation capacity of cells was examined using CCK-8, EdU, and colony formation assays; the migration and invasion of cells was detected by wound healing and transwell assays; western blotting was used to detect the levels of MMP-2, MMP-9, E-cadherin, N-cadherin and Akt phosphorylation. RESULTS: LDHs were differentially expressed in a variety of human tumor tissues. LDHs subtypes can act as pro-oncogenes or anti-oncogenes in different types of cancer and have an impact on the prognosis of patients with tumors by influencing their clinicopathological characteristics. LDHs were differentially expressed in tumor immune subtypes and molecular subtypes. In addition, LDHs expression correlated with immune checkpoint genes, tumor mutational load, and microsatellite instability. LDHD was identified to play an important role in the prognosis of HCC patients, according to a comprehensive analysis of LDHs in pan-cancer. In HepG2 and Huh7 cells, knockdown of LDHD promoted cell proliferation, migration, and invasion, promoted the protein expression levels of MMP-2, MMP-9, N-cadherin, and Akt phosphorylation, but inhibited the protein expression level of E-cadherin. In addition, LDHD overexpression showed the opposite changes. CONCLUSION: LDHs subtypes can be used as potential prognostic markers for certain cancers. Prognostic and immunotherapeutic analysis indicated that LDHD plays an important role in the prognosis of HCC patients. In vitro experiments revealed that LDHD can affect HCC proliferation, migration, and invasion by regulating MMPs expression and EMT via Akt signaling pathway, which provides a new perspective on the anti-cancer molecular mechanism of LDHD in HCC.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Caderinas/genética , Carcinoma Hepatocelular/genética , L-Lactato Desidrogenase , Neoplasias Hepáticas/genética , Metaloproteinase 2 da Matriz , Metaloproteinase 9 da Matriz , Instabilidade de Microssatélites , Prognóstico , Proteínas Proto-Oncogênicas c-akt
7.
Artigo em Inglês | MEDLINE | ID: mdl-38864839

RESUMO

A Gram-stain-positive, strictly anaerobic, endospore-forming and rod-shaped (0.6-0.8×2.7-13.1 µm) bacterium, designated as 5 N-1T, was isolated from a yellow water sample collected from the manufacturing process of Nongxiangxing baijiu in the Yibin region of Sichuan, PR China. Growth occurred at 15-40 °C (optimum growth at 37 °C), at pH 6.0-9.0 (optimum growth at pH 7.0) and in NaCl concentrations of 0-1 % (w/v) and ethanol concentrations of 0-2 % (v/v). The major fatty acids in strain 5 N-1T were C16 : 0, C18 : 0 and C14 : 0. The polar lipids were diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, four unidentified aminophospholipids and one unidentified lipid. Phylogenetic analysis of its 16S rRNA gene sequence indicated that strain 5 N-1T was most closely related to Clostridium weizhouense YB-6T (97.70 %) and Clostridium uliginosum DSM 12992T (97.56 %). The average nucleotide identity and digital DNA‒DNA hybridization values between strain 5 N-1T and the above two type strains were 80.89 and 80.05 % and 25.80 and 25.30 %, respectively, which were all below the species thresholds. The genome size of strain 5 N-1T was 3.5 Mbp and the DNA G+C content was 27.5 mol%. Based on the results of phenotypic and genotypic analyses, strain 5 N-1T represents a novel species of the genus Clostridium, for which the name Clostridium aquiflavi sp. nov. is proposed. The type strain is Clostridium aquiflavi 5 N-1T (=CICC 24886T=JCM 35355T).


Assuntos
Técnicas de Tipagem Bacteriana , Composição de Bases , Clostridium , DNA Bacteriano , Ácidos Graxos , Hibridização de Ácido Nucleico , Filogenia , RNA Ribossômico 16S , Análise de Sequência de DNA , China , RNA Ribossômico 16S/genética , Ácidos Graxos/análise , DNA Bacteriano/genética , Clostridium/genética , Clostridium/isolamento & purificação , Clostridium/classificação , Microbiologia da Água , Fosfolipídeos/análise
8.
Eur Radiol ; 34(3): 1659-1666, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37672054

RESUMO

OBJECTIVE: To report the results of a dose survey conducted across 31 provinces in mainland China from 2017 to 2018 and to analyse the dose level to determine the national diagnostic reference levels (DRLs) for paediatric CT procedures. METHODS: At least ten patients for each age group (0- < 1, 1- < 5, 5- < 10, 10- < 15 years) and each procedure (head, chest and abdomen) for each CT scanner were selected from four to eight hospitals in each province. The dose information (CTDIvol and DLP) was collected from the HIS or RIS-PACS systems. The median values in each CT scanner were considered the representative dose values for the paediatric patients in CT scanning. The national DRLs were estimated based on the 75th percentile distribution of the median values. RESULTS: A total of 24,395 patients and 319 CT scanners were investigated across 262 hospitals. For paediatric CT scanning in 4 different age groups, the median (P50) and the 75th percentile (P75) of CTDIvol and DLP for each scanning procedure were calculated and reported. National DRLs were then proposed for each procedure and age group. CONCLUSION: The dose level of CT scanning for children in mainland China was reported for the first time. The DRLs for paediatric CT in the present study are similar to those in some Asian countries but higher than those in European countries. CLINICAL RELEVANCE STATEMENT: The paediatric CT is an extensively used tool in diagnosing paediatric disease; however, children are more sensitive to radiation. Establishing the diagnostic reference level of paediatric CT examination is necessary to reduce the dose of CT in children and promote the optimisation of medical exposure. KEY POINTS: • The DRLs for 3 paediatric CT procedures (head, chest and abdomen) and 4 age groups (0- < 1, 1- < 5, 5- < 10, 10- < 15 years) were proposed in mainland China first time. • The examination parameter and dose for children need to be further optimised in China, especially to lower the tube voltage in paediatric CT.


Assuntos
Tórax , Tomografia Computadorizada por Raios X , Criança , Humanos , Adolescente , Doses de Radiação , Valores de Referência , Tomografia Computadorizada por Raios X/métodos , China/epidemiologia
9.
Mol Cell ; 64(4): 673-687, 2016 11 17.
Artigo em Inglês | MEDLINE | ID: mdl-27840030

RESUMO

Distinctive from their normal counterparts, cancer cells exhibit unique metabolic dependencies on glutamine to fuel anabolic processes. Specifically, pancreatic ductal adenocarcinoma (PDAC) cells rely on an unconventional metabolic pathway catalyzed by aspartate aminotransferase, malate dehydrogenase 1 (MDH1), and malic enzyme 1 to rewire glutamine metabolism and support nicotinamide adenine dinucleotide phosphate (NADPH) production. Here, we report that methylation on arginine 248 (R248) negatively regulates MDH1. Protein arginine methyltransferase 4 (PRMT4/CARM1) methylates and inhibits MDH1 by disrupting its dimerization. Knockdown of MDH1 represses mitochondria respiration and inhibits glutamine metabolism, which sensitizes PDAC cells to oxidative stress and suppresses cell proliferation. Meanwhile, re-expression of wild-type MDH1, but not its methylation-mimetic mutant, protects cells from oxidative injury and restores cell growth and clonogenic activity. Importantly, MDH1 is hypomethylated at R248 in clinical PDAC samples. Our study reveals that arginine methylation of MDH1 by CARM1 regulates cellular redox homeostasis and suppresses glutamine metabolism of pancreatic cancer.


Assuntos
Carcinoma Ductal Pancreático/genética , Regulação Neoplásica da Expressão Gênica , Glutamina/metabolismo , Malato Desidrogenase (NADP+)/genética , Neoplasias Pancreáticas/genética , Proteína-Arginina N-Metiltransferases/genética , Arginina/metabolismo , Carcinoma Ductal Pancreático/metabolismo , Carcinoma Ductal Pancreático/patologia , Linhagem Celular Tumoral , Proliferação de Células , Células HEK293 , Humanos , Malato Desidrogenase (NADP+)/antagonistas & inibidores , Malato Desidrogenase (NADP+)/metabolismo , Metilação , Mitocôndrias/genética , Mitocôndrias/metabolismo , Mitocôndrias/patologia , Modelos Moleculares , NADP/biossíntese , Oxirredução , Neoplasias Pancreáticas/metabolismo , Neoplasias Pancreáticas/patologia , Multimerização Proteica , Estrutura Secundária de Proteína , Proteína-Arginina N-Metiltransferases/metabolismo , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/metabolismo , Transdução de Sinais
10.
Prenat Diagn ; 44(1): 81-87, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-38148006

RESUMO

To report two novel TTN variants associated with fetal recessive titinopathy, thereby broadening the range of TTN variants that can lead to titinopathy. Clinical information on the fetus and parents was gathered, and genomic DNAs were extracted from the fetal tissue and family members' peripheral blood samples. Exome sequencing on fetal DNA was performed and following bioinformatics analysis, the suspected pathogenic variants were confirmed through Sanger sequencing. Prenatal ultrasound performed at 29 weeks of gestation revealed hydrops fetalis, decreased fetal movements, multiple joint contractures and polyhydramnios. Intrauterine fetal death was noted in the third trimester. Exome sequencing revealed compound heterozygous variants in the TTN gene: a paternally inherited allele c.101227C>T (p.Arg33743Ter) and a maternally inherited c.104254C>T (p.Gln34752Ter) allele. These variants have not been previously reported and are evaluated to be likely pathogenic according to the American College of Medical Genetics and Genomics guidelines. We report a fetus with hydrops fetalis and arthrogryposis multiplex congenita associated with a compound heterozygote in the TTN gene. Our report broadens the clinical and genetic spectrum associated with the TTN-related conditions.


Assuntos
Artrogripose , Hidropisia Fetal , Gravidez , Feminino , Humanos , Hidropisia Fetal/diagnóstico por imagem , Hidropisia Fetal/genética , Éxons , Artrogripose/diagnóstico por imagem , Artrogripose/genética , Terceiro Trimestre da Gravidez , Feto/diagnóstico por imagem , Conectina/genética
11.
BMC Public Health ; 24(1): 1411, 2024 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-38802825

RESUMO

BACKGROUND: Preterm birth (PTB) is an important predictor of perinatal morbidity and mortality. Previous researches have reported a correlation between air pollution and an increased risk of preterm birth. However, the specific relationship between short-term and long-term exposure to carbon monoxide (CO) and preterm birth remains less explored. METHODS: A population-based study was conducted among 515,498 pregnant women in Chongqing, China, to assess short-term and long-term effects of CO on preterm and very preterm births. Generalized additive models (GAM) were applied to evaluate short-term effects, and exposure-response correlation curves were plotted after adjusting for confounding factors. Hazard ratios (HR) and 95% confidence intervals (CI) were calculated using COX proportional hazard models to estimate the long-term effect. RESULTS: The daily incidence of preterm and very preterm birth was 5.99% and 0.41%, respectively. A positive association between a 100 µg/m³ increase in CO and PTB was observed at lag 0-3 days and 12-21 days, with a maximum relative risk (RR) of 1.021(95%CI: 1.001-1.043). The exposure-response curves (lag 0 day) revealed a rapid increase in PTB due to CO. Regarding long-term exposure, positive associations were found between a 100 µg/m3 CO increase for each trimester(Model 2 for trimester 1: HR = 1.054, 95%CI: 1.048-1.060; Model 2 for trimester 2: HR = 1.066, 95%CI: 1.060-1.073; Model 2 for trimester 3: HR = 1.007, 95%CI: 1.001-1.013; Model 2 for entire pregnancy: HR = 1.080, 95%CI: 1.073-1.088) and higher HRs of very preterm birth. Multiplicative interactions between air pollution and CO on the risk of preterm and very preterm birth were detected (P- interaction<0.05). CONCLUSIONS: Our findings suggest that short-term exposure to low levels of CO may have protective effects against preterm birth, while long-term exposure to low concentrations of CO may reduce the risk of both preterm and very preterm birth. Moreover, our study indicated that very preterm birth is more susceptible to the influence of long-term exposure to CO during pregnancy, with acute CO exposure exhibiting a greater impact on preterm birth. It is imperative for pregnant women to minimize exposure to ambient air pollutants.


Assuntos
Poluentes Atmosféricos , Monóxido de Carbono , Nascimento Prematuro , Humanos , Feminino , Gravidez , Nascimento Prematuro/epidemiologia , China/epidemiologia , Monóxido de Carbono/análise , Adulto , Poluentes Atmosféricos/análise , Poluentes Atmosféricos/efeitos adversos , Poluição do Ar/efeitos adversos , Poluição do Ar/análise , Recém-Nascido , Exposição Materna/efeitos adversos , Exposição Materna/estatística & dados numéricos , Fatores de Tempo , Adulto Jovem , Fatores de Risco
12.
Ren Fail ; 46(1): 2330629, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38494199

RESUMO

Acetaminophen (APAP)-induced acute kidney injury (APAP-AKI) has turned into one of reasons for clinic obtained renal insufficiency. Magnesium hydride (MgH2), as a solid-state hydrogen source, might be potentially applied in clinical practice. The current study aimed to investigate the protective effect of MgH2 against APAP-AKI. The results showed that MgH2 improved renal function and histological injury in mice of APAP-AKI. MgH2 also had protective effects on APAP-induced cytotoxicity in HK-2 cells. In addition, the increased level of reactive oxygen species (ROS) and expressions of inflammatory cytokines (TNF-α and IL-1ß) and pro-apoptotic factors (Bad, Bax, Caspase3, and CytC) induced by APAP were downregulated with MgH2 treatment. Furthermore, the expressions of molecules related to TXNIP/NLRP3/NF-κB pathway (TXNIP, NLRP3, NF-κB p65 and p-NF-κB p65) in renal tissues and HK-2 cells were enhanced by APAP overdose, which were reduced by MgH2 administration. Collectively, this study indicated that MgH2 protects against APAP-AKI by alleviating oxidative stress, inflammation and apoptosis via inhibition of TXNIP/NLRP3/NF-κB signaling pathway.


Assuntos
Injúria Renal Aguda , Doença Hepática Induzida por Substâncias e Drogas , Camundongos , Animais , NF-kappa B/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Acetaminofen/toxicidade , Magnésio , Estresse Oxidativo , Injúria Renal Aguda/induzido quimicamente , Injúria Renal Aguda/prevenção & controle
13.
J Asian Nat Prod Res ; 26(8): 892-899, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38600044

RESUMO

Two new triterpene fatty acid esters, 3ß-palmityloxy-12,27-cyclofriedoolean-14-en-11α-ol (1) and 3ß-palmityloxy-19α-hydroxyursane (2), together with 3ß-hydroxy-11-oxo-olean-12-enyl palmitate (3) were isolated from the potent anti-inflammatory active fraction of the petroleum ether-soluble part of Cirsium setosum ethanol extract. Compound 1 was found to be a rare 12,27-cyclopropane triterpenoid. Their structures were determined through spectral data analysis combined with literature reports. Furthermore, in vitro experiment, compounds 1-3 exhibited significant inhibitory effects on nitric oxide production in lipopolysaccharide-activated mouse RAW264.7 macrophages.


Assuntos
Anti-Inflamatórios , Cirsium , Ésteres , Lipopolissacarídeos , Óxido Nítrico , Triterpenos , Animais , Camundongos , Cirsium/química , Triterpenos/farmacologia , Triterpenos/química , Triterpenos/isolamento & purificação , Estrutura Molecular , Óxido Nítrico/biossíntese , Óxido Nítrico/antagonistas & inibidores , Células RAW 264.7 , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/química , Lipopolissacarídeos/farmacologia , Ésteres/farmacologia , Ésteres/química , Macrófagos/efeitos dos fármacos
14.
Molecules ; 29(11)2024 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-38893354

RESUMO

Metal halide perovskites have attracted considerable attention as novel optoelectronic materials for their excellent optical and electrical properties. Inorganic perovskites (CsPbX3, X = Cl, Br, I) are now viable alternative candidates for third-generation photovoltaic technology because of their high photoelectric conversion efficiency, high carrier mobility, good defect tolerance, simple preparation method and many other advantages. However, the toxicity of lead is problematic for practical implementation. Thus, the fabrication of lead-free perovskite materials and devices has been actively conducted. In this work, the energy band and photoelectric properties of inorganic perovskites CsBX3 (B = Pb, Sn, Ge, X = Cl, Br, I) have been investigated with the first principles calculation, and the possible defect energy levels and their formation energies in different components, in particular, have been systematically studied. The advantages and disadvantages of Sn and Ge as replacement elements for Pb have been demonstrated from the perspective of defects. This study provides an important basis for the study of the properties and applications of lead-free perovskites.

15.
Int Wound J ; 21(4): e14867, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38597295

RESUMO

Non-healing wounds are one of the chronic complications of diabetes and have remained a worldwide challenge as one of the major health problems. Hyperbaric oxygen (HBO) therapy is proven to be very successful for diabetic wound treatment, for which the molecular basis is not understood. Adipocytes regulate multiple aspects of repair and may be therapeutic for inflammatory diseases and defective wound healing associated with aging and diabetes. Endothelial cell-derived extracellular vesicles could promote wound healing in diabetes. To study the mechanism by which HBO promotes wound healing in diabetes, we investigated the effect of HBO on fat cells in diabetic mice. A diabetic wound mouse model was established and treated with HBO. Haematoxylin and eosin (H&E) staining and immunofluorescence were used for the analysis of wound healing. To further explore the mechanism, we performed whole-genome sequencing on extracellular vesicles (EVs). Furthermore, we conducted in vitro experiments. Specifically, exosomes were collected from human umbilical vein endothelial cell (HUVEC) cells after HBO treatment, and then these exosomes were co-incubated with adipose tissue. The wound healing rate in diabetic mice treated with HBO was significantly higher. HBO therapy promotes the proliferation of adipose precursor cells. HUVEC-derived exosomes treated with HBO significantly promoted fat cell browning. These data clarify that HBO therapy may promote vascular endothelial cell proliferation and migration, and promote browning of fat cells through vascular endothelial cells derived exosomes, thereby promoting diabetic wound healing. This provides new ideas for the application of HBO therapy in the treatment of diabetic trauma.


Assuntos
Diabetes Mellitus Experimental , Oxigenoterapia Hiperbárica , Humanos , Animais , Camundongos , Cicatrização/fisiologia , Diabetes Mellitus Experimental/terapia , Células Endoteliais da Veia Umbilical Humana , Tecido Adiposo Branco
16.
Sheng Wu Yi Xue Gong Cheng Xue Za Zhi ; 41(2): 228-236, 2024 Apr 25.
Artigo em Zh | MEDLINE | ID: mdl-38686402

RESUMO

Conventional maximum intensity projection (MIP) images tend to ignore some morphological features in the detection of intracranial aneurysms, resulting in missed detection and misdetection. To solve this problem, a new method for intracranial aneurysm detection based on omni-directional MIP image is proposed in this paper. Firstly, the three-dimensional magnetic resonance angiography (MRA) images were projected with the maximum density in all directions to obtain the MIP images. Then, the region of intracranial aneurysm was prepositioned by matching filter. Finally, the Squeeze and Excitation (SE) module was used to improve the CaraNet model. Excitation and the improved model were used to detect the predetermined location in the omni-directional MIP image to determine whether there was intracranial aneurysm. In this paper, 245 cases of images were collected to test the proposed method. The results showed that the accuracy and specificity of the proposed method could reach 93.75% and 93.86%, respectively, significantly improved the detection performance of intracranial aneurysms in MIP images.


Assuntos
Algoritmos , Imageamento Tridimensional , Aneurisma Intracraniano , Angiografia por Ressonância Magnética , Aneurisma Intracraniano/diagnóstico por imagem , Humanos , Angiografia por Ressonância Magnética/métodos , Imageamento Tridimensional/métodos , Sensibilidade e Especificidade , Processamento de Imagem Assistida por Computador/métodos
17.
Angew Chem Int Ed Engl ; : e202412103, 2024 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-38979667

RESUMO

7-Aminoindoles are important synthetic intermediates to a broad range of bioactive molecules. Transition metal-catalyzed directed C-H amination is among the most straightforward route for their synthesis, whereas methods that could directly incorporate an NH2 group in a highly selective manner remains elusive. Moreover, there is still high demand for the development of earth-abundant metal catalysis for such attractive reactivity. We present here the first C-7 selective NH2 amination of indoles through a directed homolytic aromatic substitution (HAS) with iron-aminyl radical. The reaction exhibits broad substrate scope, tolerates variety of functional groups, and is readily scalable with catalyst loading down to 0.1 mol% and turnover number (TON) up to 4500.

18.
BMC Genomics ; 24(1): 86, 2023 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-36829105

RESUMO

BACKGROUND: Prenatal stress (PS) is considered as a risk factor for many mental disorders. PS-induced transcriptomic alterations may contribute to the functional dysregulation during brain development. Here, we used RNA-seq to explore changes of gene expression in the mouse fetal brain after prenatal exposure to chronic unpredictable mild stress (CUMS). RESULTS: We compared the stressed brains to the controls and identified groups of significantly differentially expressed genes (DEGs). GO analysis on up-regulated DEGs revealed enrichment for the cell cycle pathways, while down-regulated DEGs were mostly enriched in the neuronal pathways related to synaptic transmission. We further performed cell-type enrichment analysis using published scRNA-seq data from the fetal mouse brain and revealed cell-type-specificity for up- and down-regulated DEGs, respectively. The up-regulated DEGs were highly enriched in the radial glia, while down-regulated DEGs were enriched in different types of neurons. Cell deconvolution analysis further showed altered cell fractions in the stressed brain, indicating accumulation of neuroblast and impaired neurogenesis. Moreover, we also observed distinct brain-region expression pattern when mapping DEGs onto the developing Allen brain atlas. The up-regulated DEGs were primarily enriched in the dorsal forebrain regions including the cortical plate and hippocampal formation. Surprisingly, down-regulated DEGs were found excluded from the cortical region, but highly expressed on various regions in the ventral forebrain, midbrain and hindbrain. CONCLUSION: Taken together, we provided an unbiased data source for transcriptomic alterations of the whole fetal brain after chronic PS, and reported differential cell-type and brain-region vulnerability of the developing brain in response to environmental insults during the pregnancy.


Assuntos
Perfilação da Expressão Gênica , Transcriptoma , Animais , Camundongos , Ciclo Celular , RNA-Seq , Encéfalo
19.
J Am Chem Soc ; 145(28): 15589-15599, 2023 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-37410888

RESUMO

Deoxygenation of phosphine oxides is of great significance to synthesis of phosphorus ligands and relevant catalysts, as well as to the sustainability of phosphorus chemistry. However, the thermodynamic inertness of P═O bonds poses a severe challenge to their reduction. Previous approaches in this regard rely primarily on a type of P═O bond activation with either Lewis/Brønsted acids or stoichiometric halogenating reagents under harsh conditions. Here, we wish to report a novel catalytic strategy for facile and efficient deoxygenation of phosphine oxides via successive isodesmic reactions, whose thermodynamic driving force for breaking the strong P═O bond was compensated by a synchronous formation of another P═O bond. The reaction was enabled by PIII/P═O redox sequences with the cyclic organophosphorus catalyst and terminal reductant PhSiH3. This catalytic reaction avoids the use of the stoichiometric activator as in other cases and features a broad substrate scope, excellent reactivities, and mild reaction conditions. Preliminary thermodynamic and mechanistic investigations disclosed a dual synergistic role of the catalyst.

20.
J Hepatol ; 78(2): 281-292, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36208843

RESUMO

BACKGROUND & AIMS: Diabetes mellitus (DM) is known to increase the risk of hepatocellular carcinoma (HCC) among individuals with chronic hepatitis C (CHC). We aimed to evaluate whether metformin reduces HCC risk among individuals with DM and CHC after successful antiviral therapy. METHODS: Individuals with CHC who achieved a sustained virological response (SVR) after interferon-based therapy were enrolled in a large-scale, multicenter cohort in Taiwan (T-COACH). Cases of HCC at least 1 year after SVR were identified through linkage to the catastrophic illness and cancer registry databases. RESULTS: Of 7,249 individuals with CHC enrolled in the study, 781 (10.8%) had diabetes and 647 (82.8%) were metformin users. During a median follow-up of 4.4 years, 227 patients developed new-onset HCC. The 5-year cumulative HCC incidence was 10.9% in non-metformin users and 2.6% in metformin users, compared to 3.0% in individuals without DM (adjusted hazard ratio [aHR] 2.83; 95% CI 1.57-5.08 and aHR 1.46; 95% CI 0.98-2.19, respectively). Cirrhosis was the most important factor significantly associated with higher HCC risk in Cox regression analysis, followed by DM non-metformin use, older age, male sex, and obesity; whereas hyperlipidemia with statin use was associated with a lower HCC risk. Using the two most crucial risk factors, cirrhosis and DM non-metformin use, we constructed a simple risk model that could predict HCC risk among individuals with CHC after SVR. Metformin use was shown to reduce the risk of all liver-related complications. CONCLUSIONS: Metformin use greatly reduced HCC risk after successful antiviral therapy in individuals with diabetes and CHC. A simple risk stratification model comprising cirrhosis and DM non-metformin use could predict long-term outcomes in individuals with CHC after SVR. IMPACT AND IMPLICATIONS: The current study provides evidence that metformin could reduce hepatocellular carcinoma (HCC) incidence after successful antiviral therapy among those with diabetes and chronic hepatitis C in a large-scale nationwide cohort study. Although successful antiviral therapy greatly reduces HCC risk in individuals with chronic hepatitis C, those with cirrhosis, diabetes, obesity, and the elderly remain at high risk of HCC development. We demonstrated that a simple risk model composed of two crucial unfavorable factors, cirrhosis and diabetes without metformin use, predicts the risk of HCC and major liver-related complications after successful antiviral therapy in individuals with chronic hepatitis C. Metformin use is highly recommended for individuals with diabetes and chronic hepatitis C after viral eradication to reduce the risk of HCC.


Assuntos
Carcinoma Hepatocelular , Diabetes Mellitus , Hepatite C Crônica , Neoplasias Hepáticas , Metformina , Humanos , Masculino , Idoso , Carcinoma Hepatocelular/epidemiologia , Carcinoma Hepatocelular/etiologia , Carcinoma Hepatocelular/prevenção & controle , Hepatite C Crônica/complicações , Hepatite C Crônica/tratamento farmacológico , Hepatite C Crônica/epidemiologia , Neoplasias Hepáticas/epidemiologia , Neoplasias Hepáticas/etiologia , Neoplasias Hepáticas/prevenção & controle , Antivirais/uso terapêutico , Estudos de Coortes , Metformina/uso terapêutico , Incidência , Taiwan/epidemiologia , Estudos Retrospectivos , Diabetes Mellitus/tratamento farmacológico , Diabetes Mellitus/epidemiologia , Cirrose Hepática/complicações , Resposta Viral Sustentada , Obesidade/complicações
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