Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 216
Filtrar
Mais filtros

Base de dados
País/Região como assunto
Tipo de documento
Intervalo de ano de publicação
1.
Plant Mol Biol ; 114(4): 77, 2024 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-38909327

RESUMO

As self-incompatibility is a major issue in pummelo breeding and production, its mechanism in citrus was analyzed to improve breeding efficiency and reduce production costs. Rutaceae belongs to S-RNase type of gametophytic self-incompatibility. While the function of S-RNase/SLF and the mechanism of self-incompatibility have been studied extensively, the transcriptional regulation of S-RNase has been less studied. We performed transcriptome sequencing with the styles of 'Shatian' pummelo on the day of anthesis and 1-5 days before anthesis, and found that the transcript level of S-RNase gradually decreased with flower development. By analyzing differentially expressed genes and correlation with the expression trend of S-RNase, we identified a candidate gene, CgHSFB1, and utilized biochemical experiments such as yeast one-hybrid assay, electrophoretic mobility shift assay and dual-luciferase assay, as well as transient transformation of citrus calli and Citrus microcarpa and demonstrated that CgHSFB1 could directly bind to the S1-RNase promoter and repress the expression of S1-RNase, which is involved in the pummelo self-incompatibility response. In contrast, CgHSFB1 did not bind to the promoter of S2-RNase, and there was specificity in the regulation of S-RNase.


Assuntos
Citrus , Flores , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas , Ribonucleases , Autoincompatibilidade em Angiospermas , Citrus/genética , Citrus/fisiologia , Citrus/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Flores/genética , Flores/fisiologia , Flores/crescimento & desenvolvimento , Autoincompatibilidade em Angiospermas/genética , Ribonucleases/genética , Ribonucleases/metabolismo , Regiões Promotoras Genéticas/genética , Transcriptoma , Perfilação da Expressão Gênica
2.
Plant Biotechnol J ; 22(5): 1113-1131, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38038155

RESUMO

Self-incompatibility (SI) is a widespread prezygotic mechanism for flowering plants to avoid inbreeding depression and promote genetic diversity. Citrus has an S-RNase-based SI system, which was frequently lost during evolution. We previously identified a single nucleotide mutation in Sm-RNase, which is responsible for the loss of SI in mandarin and its hybrids. However, little is known about other mechanisms responsible for conversion of SI to self-compatibility (SC) and we identify a completely different mechanism widely utilized by citrus. Here, we found a 786-bp miniature inverted-repeat transposable element (MITE) insertion in the promoter region of the FhiS2-RNase in Fortunella hindsii Swingle (a model plant for citrus gene function), which does not contain the Sm-RNase allele but are still SC. We demonstrate that this MITE plays a pivotal role in the loss of SI in citrus, providing evidence that this MITE insertion prevents expression of the S-RNase; moreover, transgenic experiments show that deletion of this 786-bp MITE insertion recovers the expression of FhiS2-RNase and restores SI. This study identifies the first evidence for a role for MITEs at the S-locus affecting the SI phenotype. A family-wide survey of the S-locus revealed that MITE insertions occur frequently adjacent to S-RNase alleles in different citrus genera, but only certain MITEs appear to be responsible for the loss of SI. Our study provides evidence that insertion of MITEs into a promoter region can alter a breeding strategy and suggests that this phenomenon may be broadly responsible for SC in species with the S-RNase system.


Assuntos
Citrus , Elementos de DNA Transponíveis , Elementos de DNA Transponíveis/genética , Citrus/genética , Melhoramento Vegetal , Mutação , Ribonucleases/metabolismo
3.
J Transl Med ; 22(1): 248, 2024 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-38454480

RESUMO

BACKGROUND: Acute ischemic stroke is a common neurological disease with a significant financial burden but lacks effective drugs. Hypoxia-inducible factor (HIF) and prolyl hydroxylases (PHDs) participate in the pathophysiological process of ischemia. However, whether FG4592, the first clinically approved PHDs inhibitor, can alleviate ischemic brain injury remains unclear. METHODS: The infarct volumes and behaviour tests were first analyzed in mice after ischemic stroke with systemic administration of FG4592. The knockdown of HIF-1α and pretreatments of HIF-1/2α inhibitors were then used to verify whether the neuroprotection of FG4592 is HIF-dependent. The targets predicting and molecular docking methods were applied to find other targets of FG4592. Molecular, cell biological and gene knockdown methods were finally conducted to explore the potential neuroprotective mechanisms of FG4592. RESULTS: We found that the systemic administration of FG4592 decreased infarct volume and improved neurological defects of mice after transient or permanent ischemia. Meanwhile, FG4592 also activated autophagy and inhibited apoptosis in peri-infarct tissue of mice brains. However, in vitro and in vivo results suggested that the neuroprotection of FG4592 was not classical HIF-dependent. 2-oxoglutarate and iron-dependent oxygenase domain-containing protein 1 (OGFOD1) was found to be a novel target of FG4592 and regulated the Pro-62 hydroxylation in the small ribosomal protein s23 (Rps23) with the help of target predicting and molecular docking methods. Subsequently, the knockdown of OGFOD1 protected the cell against ischemia/reperfusion injury and activated unfolded protein response (UPR) and autophagy. Moreover, FG4592 was also found to activate UPR and autophagic flux in HIF-1α independent manner. Blocking UPR attenuated the neuroprotection, pro-autophagy effect and anti-apoptosis ability of FG4592. CONCLUSION: This study demonstrated that FG4592 could be a candidate drug for treating ischemic stroke. The neuroprotection of FG4592 might be mediated by inhibiting alternative target OGFOD1, which activated the UPR and autophagy and inhibited apoptosis after ischemic injury. The inhibition of OGFOD1 is a novel therapy for ischemic stroke.


Assuntos
Isquemia Encefálica , AVC Isquêmico , Acidente Vascular Cerebral , Camundongos , Animais , Neuroproteção , Simulação de Acoplamento Molecular , Resposta a Proteínas não Dobradas , Isquemia , Autofagia , Infarto , Isquemia Encefálica/complicações , Isquemia Encefálica/tratamento farmacológico , Isquemia Encefálica/metabolismo , Acidente Vascular Cerebral/tratamento farmacológico , Acidente Vascular Cerebral/metabolismo , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo
4.
IUBMB Life ; 2024 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-38551358

RESUMO

Mitoribosomes are essential for the production of biological energy. The Human Mitoribosomal Small Subunit unit (MRPS) family, responsible for encoding mitochondrial ribosomal small subunits, is actively engaged in protein synthesis within the mitochondria. Intriguingly, MRPS family genes appear to play a role in cancer. A multistep process was employed to establish a risk model associated with MRPS genes, aiming to delineate the immune and pharmacogenomic landscapes in clear cell renal cell carcinoma (ccRCC). MRPScores were computed for individual patients to assess their responsiveness to various treatment modalities and their susceptibility to different therapeutic targets and drugs. While MRPS family genes have been implicated in various cancers as oncogenes, our findings reveal a contrasting tumor suppressor role for MRPS genes in ccRCC. Utilizing an MRPS-related risk model, we observed its excellent prognostic capability in predicting survival outcomes for ccRCC patients. Remarkably, the subgroup with high MRPS-related scores (MRPScore) displayed poorer prognosis but exhibited a more robust response to immunotherapy. Through in silico screening of 2183 drug targets and 1646 compounds, we identified two targets (RRM2 and OPRD1) and eight agents (AZ960, carmustine, lasalocid, SGI-1776, AZD8055_1059, BPD.00008900_1998, MK.8776_2046, and XAV939_1268) with potential therapeutic implications for high-MRPScore patients. Our study represents the pioneering effort in proposing that molecular classification, diagnosis, and treatment strategies can be formulated based on MRPScores. Indeed, a high MRPScore profile appears to elevate the risk of tumor progression and mortality, potentially through its influence on immune regulation. This suggests that the MRPS-related risk model holds promise as a prognostic predictor and may offer novel insights into personalized therapeutic strategies.

5.
J Nanobiotechnology ; 22(1): 224, 2024 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-38702709

RESUMO

Poorly identified tumor boundaries and nontargeted therapies lead to the high recurrence rates and poor quality of life of prostate cancer patients. Near-infrared-II (NIR-II) fluorescence imaging provides certain advantages, including high resolution and the sensitive detection of tumor boundaries. Herein, a cyanine agent (CY7-4) with significantly greater tumor affinity and blood circulation time than indocyanine green was screened. By binding albumin, the absorbance of CY7-4 in an aqueous solution showed no effects from aggregation, with a peak absorbance at 830 nm and a strong fluorescence emission tail beyond 1000 nm. Due to its extended circulation time (half-life of 2.5 h) and high affinity for tumor cells, this fluorophore was used for primary and metastatic tumor diagnosis and continuous monitoring. Moreover, a high tumor signal-to-noise ratio (up to ~ 10) and excellent preferential mitochondrial accumulation ensured the efficacy of this molecule for photothermal therapy. Therefore, we integrated NIR-II fluorescence-guided surgery and intraoperative photothermal therapy to overcome the shortcomings of a single treatment modality. A significant reduction in recurrence and an improved survival rate were observed, indicating that the concept of intraoperative combination therapy has potential for the precise clinical treatment of prostate cancer.


Assuntos
Carbocianinas , Mitocôndrias , Recidiva Local de Neoplasia , Terapia Fototérmica , Neoplasias da Próstata , Masculino , Neoplasias da Próstata/diagnóstico por imagem , Terapia Fototérmica/métodos , Humanos , Animais , Mitocôndrias/metabolismo , Mitocôndrias/efeitos dos fármacos , Linhagem Celular Tumoral , Carbocianinas/química , Imagem Óptica/métodos , Camundongos , Cirurgia Assistida por Computador/métodos , Corantes Fluorescentes/química , Camundongos Nus , Camundongos Endogâmicos BALB C , Raios Infravermelhos , Verde de Indocianina/química , Verde de Indocianina/uso terapêutico , Verde de Indocianina/farmacologia
6.
J Sep Sci ; 47(11): e2400170, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38863084

RESUMO

The glycomic analysis holds significant appeal due to the diverse roles that glycans and glycoconjugates play, acting as modulators and mediators in cellular interactions, cell/organism structure, drugs, energy sources, glyconanomaterials, and more. The glycomic analysis relies on liquid-phase separation technologies for molecular purification, separation, and identification. As a miniaturized form of liquid-phase separation technology, microscale separation technologies offer various advantages such as environmental friendliness, high resolution, sensitivity, fast speed, and integration capabilities. For glycan analysis, microscale separation technologies are continuously evolving to address the increasing challenges in their unique manners. This review discusses the fundamentals and applications of microscale separation technologies for glycomic analysis. It covers liquid-phase separation technologies operating at scales generally less than 100 µm, including capillary electrophoresis, nanoflow liquid chromatography, and microchip electrophoresis. We will provide a brief overview of glycomic analysis and describe new strategies in microscale separation and their applications in glycan analysis from 2014 to 2023.


Assuntos
Eletroforese Capilar , Glicômica , Polissacarídeos , Glicômica/métodos , Polissacarídeos/química , Polissacarídeos/isolamento & purificação , Polissacarídeos/análise , Humanos , Cromatografia Líquida , Eletroforese em Microchip/métodos
7.
Semin Cancer Biol ; 86(Pt 3): 931-950, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-33979677

RESUMO

The success of conventional cancer therapeutics is hindered by associated dreadful side-effects of antibiotic resistance and the dearth of antitumor drugs' selectivity and specificity. Hence, the conceptual evolution of anti-cancerous therapeutic agents that selectively target cancer cells without impacting the healthy cells or tissues, has led to a new wave of scientific interest in microbial-derived bioactive molecules. Such strategic solutions may pave the way to surmount the shortcomings of conventional therapies and raise the potential and hope for the cure of wide range of cancer in a selective manner. This review aims to provide a comprehensive summary of anti-carcinogenic properties and underlying mechanisms of bioactive molecules of microbial origin, and discuss the current challenges and effective therapeutic application of combinatorial strategies to attain minimal systemic side-effects.


Assuntos
Antineoplásicos , Neoplasias , Humanos , Neoplasias/tratamento farmacológico , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico
8.
Arterioscler Thromb Vasc Biol ; 42(5): 613-631, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35387479

RESUMO

BACKGROUND: Macrophages are involved in the pathogenesis of pulmonary arterial hypertension (PAH). Caspase-8, an apical component of cell death pathways, is significantly upregulated in macrophages of PAH animal models. However, its role in PAH remains unclear. Caspase-8 plays a critical role in regulating inflammatory responses via inflammasome activation, cell death, and cytokine induction. This study investigated the mechanism of regulation of IL-1ß (interleukin 1ß) activation in macrophages by caspase-8. METHODS: A hypoxia + SU5416-induced PAH mouse model and monocrotaline-induced rat model of PAH were constructed and the role of caspase-8 was analyzed. RESULTS: Caspase-8 and cleaved-caspase-8 were significantly upregulated in the lung tissues of SU5416 and hypoxia-treated PAH mice and monocrotaline-treated rats. Pharmacological inhibition of caspase-8 alleviated PAH compared with wild-type mice, observed as a significant reduction in right ventricular systolic pressure, ratio of right ventricular wall to left ventricular wall plus ventricular septum, pulmonary vascular media thickness, and pulmonary vascular muscularization; caspase-8 ablated mice also showed significant remission. Mechanistically, increased proliferation of pulmonary arterial smooth muscle cellss is closely associated with activation of the NLRP3 (NOD [nucleotide oligomerization domain]-, LRR [leucine-rich repeat]-, and PYD [pyrin domain]-containing protein 3) inflammasome and the IL-1ß signaling pathway. Although caspase-8 did not affect extracellular matrix synthesis, it promoted inflammatory cell infiltration and pulmonary arterial smooth muscle cell proliferation via NLRP3/IL-1ß activation during the development stage of PAH. CONCLUSIONS: Taken together, our study suggests that macrophage-derived IL-1ß via caspase-8-dependent canonical inflammasome is required for macrophages to play a pathogenic role in pulmonary perivascular inflammation.


Assuntos
Hipertensão Pulmonar , Animais , Caspase 1/metabolismo , Caspase 8/metabolismo , Hipertensão Pulmonar/induzido quimicamente , Hipertensão Pulmonar/tratamento farmacológico , Hipertensão Pulmonar/genética , Hipóxia/complicações , Inflamassomos/metabolismo , Inflamação/complicações , Interleucina-1beta/metabolismo , Macrófagos/metabolismo , Camundongos , Monocrotalina/toxicidade , Proteína 3 que Contém Domínio de Pirina da Família NLR/genética , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Ratos
9.
Phys Chem Chem Phys ; 25(31): 21054-21064, 2023 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-37525896

RESUMO

Suppressing the shuttle effect of high-order polyselenides is crucial for the development of high-performance host materials in lithium-selenium (Li-Se) batteries. Using first-principles calculations, the feasibility of Co@C3N3 monolayer as selenium cathode host material for Li-Se batteries is systematically evaluated from the aspects of binding energy, charge transfer mechanism, and catalytic effect of polyselenides in the present work. The Co@C3N3 monolayer can effectively prevent the solubilization of high-order polyselenides with large binding energy and charge transfer resulting from the synergistic effect of Li-N and Co-Se bonds. The polyselenides are inclined to adsorb on the surface of Co@C3N3 monolayer instead of interacting with the electrolytes, which effectively inhibits the shuttling of high-order polyselenides and improves cycling stability. The cobalt participation improves the conductivity of C3N3 monolayer, and the semi-metallic characteristics of the Co@C3N3 monolayer are maintained after the adsorption of Li2Sen (n = 1, 2, 4, 6, 8) or Se8 clusters, which is advantageous for the utilization of active selenium material. The crucial catalytic role of the Co@C3N3 monolayer is evaluated by examining the reduction pathway of Se8 and the decomposition barrier of Li2Se, and the results highlight the capability of Co@C3N3 monolayer to enhance the utilization of selenium and promote the transition of Li2Se. Our present work could not only provide valuable insights into the anchoring and catalytic effect of Co@C3N3 monolayer, but also shed light on the future investigation on the high performance C3N3-based host materials for Li-Se batteries.

10.
Appl Opt ; 62(26): 6892-6898, 2023 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-37707027

RESUMO

Stimulated Brillouin scattering (SBS) is effective for realizing a laser with an ultra-narrow linewidth. Although photonic crystal fiber (PCF) is considered an excellent medium to achieve SBS, it does not meet the requirements of low loss, large birefringence, and ease of fabrication. We propose a polarization-maintaining PCF (PM-PCF) structure and theoretically analyze the effects of the geometric structural parameters of the PM-PCF on various optical properties. Our theoretical analysis and experimental results contribute to the advancement of the field of ultra-narrow linewidth fiber lasers, distributed fiber sensing, and fiber-optic gyroscopes related to SBS.

11.
Biomed Chromatogr ; 37(4): e5589, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36689998

RESUMO

Li-Zhong-Xiao-Pi granules (LZXP) are effective for treating gastric precancerous lesions (GPL) in traditional Chinese medicine. However, the active compounds of LZXP and their potential therapeutic mechanism in GPL remained unclarified. The purpose of this study is to investigate the chemical composition and potential targets of LZXP. Based on the accurate masses, ion fragments, and literature data, a total of 128 compounds were identified in the LZXP sample using ultra-performance liquid chromatography and quadrupole time-of-flight mass spectrometry (UPLC-Q-TOF-MS) in both positive and negative ion modes, and 28 of these compounds were exactly determined by comparison with authentic reference standards. Meanwhile, 11 typical components were quantified via UPLC during a 24 min period. The linearity, accuracy, stability and recovery of the method were all proven. Through the network pharmacological analysis, six chemicals (quercetin, 4'-hydroxywogonin, sinensetin, 5, 7, 8, 3', 4'-pentamethoxyflavanone, 8-gingerdione and quercetin) were identified as the active ingredients, and five LZXP targets (AKT1, CYP1B1, PTGS2, MMP9 and EGFR) were found to be the crucial molecules in the treatment of GPL. This study provides a systematic and applicable method for the rapid screening and identification of the chemical constituents from LZXP, and an effective understanding the mechanism of LZXP in the treatment of GPL.


Assuntos
Medicamentos de Ervas Chinesas , Cromatografia Líquida de Alta Pressão/métodos , Medicamentos de Ervas Chinesas/química , Quercetina , Farmacologia em Rede , Espectrometria de Massas/métodos
12.
Ecotoxicol Environ Saf ; 262: 115123, 2023 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-37315360

RESUMO

To explore whether paternal cadmium (Cd) exposure causes ovarian granulosa cell (GC) apoptosis in offspring and the multigenerational genetic effects. From postnatal day 28 (PND28) until adulthood (PND56), SPF male Sprague-Dawley (SD) rats were gavaged daily with varying concentrations of CdCl2. (0, 0.5, 2, and 8 mg/kg). After treatment, the F1 generation was produced by mating with untreated female rats, and the F1 generation male rats were mated with untreated female rats to produce the F2 generation. Apoptotic bodies (electron microscopy) and significantly higher apoptotic rates (flow cytometry) were observed in both F1 and F2 ovarian GCs following paternal Cd exposure. Moreover, the mRNA (qRTPCR) or protein (Western blotting) levels of bax, bcl2, bcl-xl, caspase 3, caspase 8, and caspase 9 were changed to varying degrees. Apoptosis-related miRNAs (qRTPCR) and methylation modifications of apoptosis-related genes (bisulfite-sequencing PCR) in ovarian GCs were further detected. Compared with those of controls, the expression patterns of miRNAs in F1 and F2 offspring were different after paternal Cd exposure, while the average methylation level of apoptosis-related genes did not change significantly (except for individual loci). In summary, there are paternal genetic intergenerational and transgenerational effects on ovarian GC apoptosis induced by paternal Cd exposure. These genetic effects were related to the upregulation of BAX, BCL-XL, Cle-CASPASE 3, and Cle-CASPASE 9 in F1 and the upregulation of Cle-CASPASE 3 in F2 progeny. Important changes in apoptosis-related miRNAs were also observed.

13.
Pol J Pathol ; 74(3): 151-160, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37955534

RESUMO

Recent studies revealed that programmed cell death ligand 1 (PD-L1) expression was associated with unfavorable prognosis in various solid tumors, but its clinical relevance for pancreatic cancer has not yet been well established. This meta-analysis summarizes the potential prognostic value of PD-L1 in pancreatic cancer. A quantitative meta-analysis was performed by a systematic search of databases including PubMed, EMBASE, Web of Science, Cochrane library, Scopus and Ovid for eligible studies on the prognostic significance of PD-L1 in pancreatic cancer patients. Pooled hazard ratios (HRs) and their 95% confidence intervals (CIs) were calculated to evaluate the strength of the link between PD-L1 expression and clinical prognosis of patients. Seventeen eligible studies with 2669 patients were included in our study. A significant association was observed between PD-L1 abundance and poor overall survival (OS) of patients with pancreatic cancers, with a pooled hazard ratio (HR) of 1.902, 95% CI: 1.657-2.184. Sensitivity analysis confirmed the reliability of our results. Subgroup analysis shows that differences in regions and detection methods of PD-L1 did not change the overall predictive value of PD-L1 for poor prognosis in pancreatic cancer patients. This meta-analysis indicated that the expression of PD-L1 is associated with a worse OS in pancreatic cancer patients. Additionally, PD-L1 may act as a potential parameter for predicting poor prognosis and thus providing a promising target for anticancer therapy in pancreatic cancer.


Assuntos
Antígeno B7-H1 , Neoplasias Pancreáticas , Humanos , Antígeno B7-H1/metabolismo , Biomarcadores Tumorais/metabolismo , Prognóstico , Reprodutibilidade dos Testes , Neoplasias Pancreáticas
14.
J Sci Food Agric ; 103(8): 4017-4024, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36440754

RESUMO

BACKGROUND: Mycotoxins are secondary metabolites produced by fungi, which have serious effects on humans and animals. In this study, we selected the monodispersed polystyrene fluorescent microspheres with good luminescence performance and strong stability as markers to conjugate with four mycotoxins antibodies for preparing fluorescent probes. We have developed a fluorescent microsphere based immunochromatographic assay (FMICA) to detect sensitively and quickly zearalenone (ZEN), aflatoxin B1 (AFB1 ), fumonisin B1 (FB1 ), and ochratoxin A (OTA) in cereal. RESULTS: Under optimal experimental conditions, the procedure of this method can be completed within 10 min. The limit of detection (LOD) of FMICA for ZEN, AFB1 , FB1 , and OTA is 0.072, 0.093, 0.32, and 0.19 µg L-1 , respectively. And FMICA has good specificity and no cross-reactivity with other mycotoxins. Four mycotoxins in naturally contaminated cereal samples (corn, rice, and oat) are detected by this method, and the results are highly consistent with that of ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS). CONCLUSION: The developed FMICA has good accuracy, high sensitivity, simplicity, convenience, rapidity, and low cost, and it could be employed for sensitive and quantitative detecting of mycotoxins in cereal on-site. © 2022 Society of Chemical Industry.


Assuntos
Micotoxinas , Zearalenona , Humanos , Animais , Micotoxinas/análise , Grão Comestível/química , Microesferas , Cromatografia Líquida/métodos , Espectrometria de Massas em Tandem/métodos , Zearalenona/análise , Imunoensaio/métodos , Contaminação de Alimentos/análise
15.
Angew Chem Int Ed Engl ; 62(26): e202305355, 2023 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-37096446

RESUMO

Photocatalytic oxygen reduction reaction (ORR) offers a promising hydrogen peroxide (H2 O2 ) synthetic strategy, especially the one-step two-electron (2e- ) ORR route holds great potential in achieving highly efficient and selectivity. However, efficient one-step 2e- ORR is rarely harvested and the underlying mechanism for regulating the ORR pathways remains greatly obscure. Here, by loading sulfone units into covalent organic frameworks (FS-COFs), we present an efficient photocatalyst for H2 O2 generation via one-step 2e- ORR from pure water and air. Under visible light irradiation, FS-COFs exert a superb H2 O2 yield of 3904.2 µmol h-1 g-1 , outperforming most reported metal-free catalysts under similar conditions. Experimental and theoretical investigation reveals that the sulfone units accelerate the separation of photoinduced electron-hole (e- -h+ ) pairs, enhance the protonation of COFs, and promote O2 adsorption in the Yeager-type, which jointly alters the reaction process from two-step 2e- ORR to the one-step one, thereby achieving efficient H2 O2 generation with high selectivity.


Assuntos
Peróxido de Hidrogênio , Estruturas Metalorgânicas , Humanos , Elétrons , Hipóxia , Sulfonas
16.
J Transl Med ; 20(1): 247, 2022 05 31.
Artigo em Inglês | MEDLINE | ID: mdl-35642038

RESUMO

BACKGROUND: mTOR pathway is known to promote cancer malignancy and influence cancer immunity but is unknown for its role in immune checkpoint inhibitors (ICI) therapy. METHODS: Using Memorial Sloan-Kettering Cancer Center dataset (MSKCC), we extracted mTOR pathway gene mutations for stepwise Cox regression in 1661 cancer patients received ICI. We associated the mutation of the gene signature resulted from the stepwise Cox regression with the 1661 patients' survival. Other 553 ICI-treated patients were collected from 6 cohorts for validation. We also performed this survival association in patients without ICI treatment from MSKCC as discovery (n = 2244) and The Cancer Genome Atlas (TCGA) as validation (n = 763). Pathway enrichment analysis were performed using transcriptome profiles from TCGA and IMvigor210 trial to investigate the potential mechanism. RESULTS: We identified 8 genes involved in mTOR pathway, including FGFR2, PIK3C3, FGFR4, FGFR1, FGF3, AKT1, mTOR, and RPTOR, resulted from stepwise Cox regression in discovery (n = 1661). In both discovery (n = 1661) and validation (n = 553), the mutation of the 8-gene signature was associated with better survival of the patients treated with ICI, which was independent of tumor mutation burden (TMB) and mainly attributed to the missense mutations. This survival association was not observed in patients without ICI therapy. Intriguingly, the mutation of the 8-gene signature was associated with increased TMB and PD1/PD-L1 expression. Immunologically, pathways involved in anti-tumor immune response were enriched in presence of this mutational signature in mTOR pathway, leading to increased infiltration of immune effector cells (e.g., CD8 + T cells, NK cells, and M1 macrophages), but decreased infiltration of immune inhibitory M2 macrophages. CONCLUSIONS: These results suggested that mTOR pathway gene mutations were predictive of better survival upon ICI treatment in multiple cancers, likely by its association with enhanced anti-tumor immunity. Larger studies are warranted to validate our findings.


Assuntos
Inibidores de Checkpoint Imunológico , Neoplasias , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Humanos , Inibidores de Checkpoint Imunológico/farmacologia , Inibidores de Checkpoint Imunológico/uso terapêutico , Mutação/genética , Neoplasias/tratamento farmacológico , Neoplasias/genética , Serina-Treonina Quinases TOR/genética
17.
Chirality ; 34(10): 1328-1337, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35754139

RESUMO

An on-line sample preconcentration technique based on transient trapping (tr-trapping) in micellar electrokinetic chromatography (MEKC) was applied for steroid detection with UV (tr-trapping-UV) and electrospray ionization mass spectrometry detection (tr-trapping-ESI-MS). ESI-MS was used to improve the sensitivity in MEKC. The MEKC separation was carried out using volatile ammonium formate as a background solution to facilitate the coupling with ESI-MS. The partial introduction of a sodium dodecyl sulfate (SDS) micellar solution before the introduction of a sample solution to the capillary provided the effective preconcentration of analytes. At the same time, the SDS micelle would not enter the ESI-MS system, so its interference in ESI-MS detection was suppressed under the optimal condition, then five steroids can be separated by the developed method. In tr-trapping-ESI-MS, an acidic condition of pH 3.5 was employed to suppress the electroosmotic flow, which can avoid micellar solution migrating to the MS instrument. The developed method showed that the micellar solution requires a twofold slower time than the sample to migrate along the column, which can prohibit the cause of the problem with the MS instrument and interference signal of SDS in the steroid's detection. The tr-trapping-ESI-MS protocol showed up to 540-fold enhancements of the peak intensity and 50-fold improvement of the limit of detection compared with capillary zone electrophoresis using androsterone as a model sample.


Assuntos
Cromatografia Capilar Eletrocinética Micelar , Micelas , Cromatografia Capilar Eletrocinética Micelar/métodos , Espectrometria de Massas por Ionização por Electrospray/métodos , Estereoisomerismo , Esteroides
18.
BMC Ophthalmol ; 22(1): 269, 2022 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-35725409

RESUMO

OBJECTIVES: To observe and compare the difference in retinal perfusion using optical coherence tomography angiography (OCTA) between anisometropic amblyopia in children and fellow eyes as well as age-matched controls. METHODS: A total of 16 children with anisometropic amblyopia and 19 age-matched healthy subjects were enrolled. All participants underwent OCTA examination, with 3 mm × 3 mm and 6 mm × 6 mm scans in the macular region. Perfusion parameters of the superficial retinal layer were measured by built-in software, including the macular foveal avascular zone (FAZ) area, perimeter and circularity, as well as the vessel length density (VLD) and perfusion density (PD) of the foveal, parafoveal and perifoveal regions. RESULTS: Among the 16 patients with anisometropic amblyopia, the FAZ area was significantly higher in diseased eyes (P = 0.027) than in fellow eyes. The VLD and PD of the foveal average and the VLD of the nasal quadrant of the perifoveal region in anisometropic amblyopic eyes were significantly lower than those in fellow eyes (P < 0.05). The VLD of the parafoveal average, the superior, temporal, inferior and nasal quadrants of the parafoveal region, and the nasal quadrant of the perifoveal region in anisometropic amblyopic eyes were significantly lower than those in healthy controls (P < 0.05). The PD of the parafoveal average, and the inferior quadrant of the parafoveal region in anisometropic amblyopic eyes were significantly lower than those in healthy controls (P < 0.05). The VLD of the parafoveal average, the superior, inferior and nasal quadrants of the parafoveal region, and the nasal quadrant of the perifoveal region in fellow eyes were significantly lower than those in healthy controls (P < 0.05). The PD of the parafoveal average, and the inferior quadrant of the parafoveal region in fellow eyes were significantly lower than those in healthy controls (P < 0.05). CONCLUSIONS: The macular vessel density of the superficial capillary plexus is lower in anisometropic amblyopic children than in age-matched healthy children. Compared with the fellow eye, the perfusion of the amblyopic eye in children with anisometropic amblyopia also decreases.


Assuntos
Ambliopia , Ambliopia/diagnóstico , Criança , Estudos Transversais , Angiofluoresceinografia/métodos , Humanos , Vasos Retinianos , Tomografia de Coerência Óptica/métodos , Acuidade Visual
19.
Neural Plast ; 2022: 4280410, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35369646

RESUMO

Introduction: The association between arterial tortuosity and acute ischemic stroke (AIS) has been reported, but showing inconsistent results. We hypothesized that tortuosity of extra- and intracranial large arteries might be higher in AIS patients. Furthermore, we explored the correlation between artery tortuosity and white matter hyperintensity (WMH) severity in AIS patients. Methods: 166 AIS patients identified as large artery atherosclerosis, and 83 control subjects were enrolled. All subjects received three-dimensional computed tomography angiography (CTA). Arterial tortuosity was evaluated using the tortuosity index. WMHs were evaluated using magnetic resonance imaging in all AIS patients. Results: AIS patients showed significantly increased arterial tortuosity index relative to controls, including left carotid artery (CA) (p = 0.001), right CA (p < 0.001), left common carotid artery (CCA) (p < 0.001), right CCA (p < 0.001), left internal carotid artery (p = 0.001), right internal carotid artery (p = 0.01), left extracranial internal carotid artery (EICA) (p < 0.001), right EICA (p = 0.01), and vertebral artery dominance (VAD) (p = 0.001). The tortuosity of all above arteries was associated with the presence of AIS. AIS patients with moderate or severe WMHs had a higher tortuosity index in left CA (p = 0.005), left CCA (p = 0.003), left EICA (p = 0.07), and VAD (p = 0.001). In addition, the tortuosity of left EICA and VAD was associated with WMH severity in AIS patients. Conclusions: Increased extra- and intracranial large arteries tortuosity is associated with AIS. The tortuosity of left carotid artery system and vertebral artery may be the independent risk factors for WMH severity in AIS patients. Clinical Trial Registration. This trial is registered with NCT03122002 (http://www.clinicaltrials.gov).


Assuntos
AVC Isquêmico , Dermatopatias Genéticas , Substância Branca , Artérias/anormalidades , Artéria Carótida Interna , Humanos , AVC Isquêmico/diagnóstico por imagem , Instabilidade Articular , Malformações Vasculares , Substância Branca/diagnóstico por imagem
20.
J Assist Reprod Genet ; 39(12): 2737-2746, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36322230

RESUMO

PURPOSE: Polycystic ovary syndrome is a complex heterogeneous endocrine disorder associated with established metabolic abnormalities and is a common cause of infertility in females. Glutathione metabolism in the cumulus cells (CCs) of women with PCOS may be correlated to the quality of oocytes for infertility treatment; therefore, we used a metabolomics approach to examine changes in CCs from women with PCOS and oocyte quality. METHODS: Among 135 women undergoing fertility treatment in the present study, there were 43 women with PCOS and 92 without. CCs were collected from the two groups and levels of pyroglutamic acid were measured using LC-MS/MS followed by qPCR and Western blot analysis to examine genes and proteins involved in pyroglutamic acid metabolism related to glutathione synthesis. RESULTS: Women with PCOS showed increased levels of L-pyroglutamic acid, L-glutamate, and L-phenylalanine and decreased levels of Cys-Gly and N-acetyl-L-methionine. Gene expression of OPLAH, involved in pyroglutamic synthesis, was significantly increased in women with PCOS compared with those without. Gene expression of GSS was significantly decreased in women with PCOS and synthesis of glutathione synthetase protein was decreased. Expression of nuclear factor erythroid 2-related factor 2, involved in resistance to oxidative stress, was significantly increased in women with PCOS. CONCLUSIONS: CCs of women with PCOS showed high concentrations of pyroglutamic acid and reduced glutathione synthesis, which causes oxidative stress in CCs, suggesting that decreased glutathione synthesis due to high levels of pyroglutamic acid in CCs may be related to the quality of oocytes in women with PCOS.


Assuntos
Infertilidade , Síndrome do Ovário Policístico , Humanos , Feminino , Síndrome do Ovário Policístico/genética , Síndrome do Ovário Policístico/metabolismo , Células do Cúmulo/metabolismo , Ácido Pirrolidonocarboxílico/metabolismo , Cromatografia Líquida , Espectrometria de Massas em Tandem , Oócitos/metabolismo , Infertilidade/metabolismo , Glutationa/metabolismo
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA