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1.
Front Plant Sci ; 15: 1417504, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38947951

RESUMO

Improving the nutrient content of red soils in southern China is a priority for efficient rice production there. To assess the effectiveness of oilseed rape as green manure for the improvement of soil phosphorus nutrient supply and rice yield in red soil areas, a long-term field plot experiment was conducted comparing two species of rape, Brassica napus (BN) and Brassica juncea (BJ). The effects of returning oilseed rape on soil phosphorus availability, phosphorus absorption, and yield of subsequent rice under rice-green manure rotation mode were analyzed, using data from the seasons of 2020 to 2021. The study found that compared with winter fallow treatment (WT) and no-tillage treatment (NT), the soil available phosphorus content of BN was increased, and that of BJ was significantly increased. The content of water-soluble inorganic phosphorus of BJ increased, and that of BN increased substantially. Compared with the WT, the soil organic matter content and soil total phosphorus content of BN significantly increased, as did the soil available potassium content of BJ, and the soil total phosphorus content of BJ was significantly increased compared with NT. The soil particulate phosphorus content of BJ and BN was significantly increased by 14.00% and 16.00%, respectively. Compared with the WT, the phosphorus activation coefficient of BJ was significantly increased by 11.41%. The rice plant tiller number under the green manure returning treatment was significantly increased by 43.16% compared with the winter fallow treatment. The green manure returning measures increased rice grain yield by promoting rice tiller numbers; BN increased rice grain yield by 9.91% and BJ by 11.68%. Based on these results, returning oilseed rape green manure could augment the phosphorus nutrients of red soil and promote phosphorus availability. Rice-oilseed rape green manure rotation could increase rice grain yield.

2.
Int J Surg ; 2024 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-38978471

RESUMO

The presence of tertiary lymphoid structures (TLSs) associated with distinct treatment efficacy and clinical prognosis has been identified in various cancer types. However, the mechanistic roles and clinical implications of TLSs in genitourinary (GU) cancers remain incompletely explored. Despite their potential role as predictive marker described in numerous studies, it is essential to comprehensively evaluate the characteristics of TLSs, including drivers of formation, structural foundation, cellular compositions, maturation stages, molecular features, and specific functionality to maximize their positive impacts on tumor-specific immunity. The unique contributions of these structures to cancer progression and biology have fueled interest in these structures as mediators of antitumor immunity. Emerging data are trying to explore the effects of therapeutic interventions targeting TLSs. Therefore, a better understanding of the molecular and phenotypic heterogeneity of TLSs may facilitate the development of TLSs-targeting therapeutic strategies to obtain optimal clinical benefits for GU cancers in the setting of immunotherapy. In this review, we focus on the phenotypic and functional heterogeneity of TLSs in cancer progression, current therapeutic interventions targeting TLSs and the clinical implications and therapeutic potential of TLSs in GU cancers.

3.
Huan Jing Ke Xue ; 45(7): 3789-3798, 2024 Jul 08.
Artigo em Chinês | MEDLINE | ID: mdl-39022927

RESUMO

Guanzhong urban agglomeration has a good development foundation and great development potential, and it has a unique strategic position in the national all-round opening up pattern. In recent years, the problem of near-surface ozone (O3) in the Guanzhong Region has become increasingly prominent, which has become a bottleneck affecting the continuous improvement of air quality. In order to effectively prevent and control O3 pollution, this study analyzed the characteristics of annual, monthly, and daily changes in O3 concentration in the Guanzhong Region based on the environmental monitoring data from 2018 to 2021. A geo-detector was used to study the driving factors of the spatial differentiation of O3 concentration, and the sources of O3 were analyzed using a backward trajectory model and emission inventory construction. The results showed that the daily and monthly variation in O3 concentration in the Guanzhong Region were unimodal. The daily maximum value appeared at 15:00, the minimum value appeared at 07:00, the peak value of the monthly average appeared in June, and the valley value appeared in December. The O3 concentration was highest in summer, followed by that in spring, and the lowest in winter. The days of O3 exceeding the standard showed mainly mild pollution, and moderate and above pollution showed a trend of decreasing first and then increasing. The O3 concentration in the Guanzhong Region was mainly closely related to precursors and meteorological factors, and the explanatory power of the interaction of each factor was significantly greater than that of any single factor. The regional transport of O3 concentration in the Guanzhong Region was mainly affected by easterly airflow, followed by the northwest direction, with the potential source areas located mainly in Henan Province and Hubei Province. The main local sources of volatile organic compounds (VOCs) were solvent use sources, process sources, and mobile sources, and the main emission sources of nitrogen oxides (NOx) were mobile sources and industrial production combustion sources. The research results have a guiding significance for O3 joint prevention and control in the Guanzhong Region.

5.
Nano Lett ; 2024 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-39023921

RESUMO

The doping of perovskites with mixed cations and mixed halides is an effective strategy to optimize phase stability. In this study, we introduce a cubic black phase perovskite CsyFA(1-y)Pb(BrxI(1-x))3 artificial synapse, using phase engineering by adjusting the cesium-bromide content. Low-bromine mixed perovskites are suitable to improve the electric pulse excitation sensitivity and stability of the device. Specifically, the low-bromine and low-cesium mixed perovskite (x = 0.15, y = 0.22) annealed at 373 K allows the device to maintain logic response even after 1000 mechanical flex/flat cycles. The device also shows good thermal stability up to temperatures of 333 K. We have demonstrated reflex-arc behavior with MCMHP synaptic units, capable of making sensory warnings at high frequency. This compositionally engineered, dual-mixed perovskite synaptic device provides significant potential for perceptual soft neurorobotic systems and prostheses.

6.
Oncologist ; 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38954846

RESUMO

With the widespread use of next-generation sequencing (NGS) for solid tumors, mesenchymal-to-epithelial transition factor (MET) rearrangement/fusion has been confirmed in multiple cancer types. MET amplification and MET exon 14 skipping mutations induce protein autophosphorylation; however, the pathogenic mechanism and drug sensitivity of MET fusion remain unclear. The following report describes the clinical case of a patient diagnosed with squamous lung cancer bearing a TFG-MET gene fusion. In vitro assays demonstrated MET phosphorylation and oncogenic capacity due to the TFG-MET rearrangement, both of which were inhibited by crizotinib treatment. The patient was treated with crizotinib, which resulted in sustained partial remission for more than 17 months. Collectively, cellular analyses and our case report emphasize the potential of MET fusion as a predictive biomarker for personalized target therapy for solid tumors.

7.
J Hazard Mater ; 476: 135067, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38964039

RESUMO

Endocrine-disrupting chemicals (EDCs) are persistent and pervasive compounds that pose serious risks. Numerous studies have explored the effects of EDCs on human health, among which tumors have been the primary focus. However, because of study design flaws, lack of effective exposure levels of EDCs, and inconsistent population data and findings, it is challenging to draw clear conclusions on the effect of these compounds on tumor-related outcomes. Our study is the first to systematically integrate observational studies and randomized controlled trials from over 20 years and summarize over 300 subgroup associations. We found that most EDCs promote tumor development, and that exposure to residential environmental pollutants may be a major source of pesticide exposure. Furthermore, we found that phytoestrogens exhibit antitumor effects. The findings of this study can aid in the development of global EDCs regulatory health policies and alleviate the severe risks associated with EDCs exposure.

8.
Artigo em Inglês | MEDLINE | ID: mdl-38987012

RESUMO

BACKGROUND AND AIM: Post-infection irritable bowel syndrome (PI-IBS) is well-known epidemiologically; however, its physiological and molecular characteristics are not well studied. We aimed to determine the physiological phenotypes, colonic transcriptome, fecal microbiome, and metabolome in PI-IBS. METHODS: Fifty-one Rome III Campylobacter PI-IBS patients and 39 healthy volunteers (HV) were enrolled. Participants completed questionnaires, in vivo intestinal permeability, gastrointestinal transit, and rectal sensation. Fecal samples were collected for shotgun metagenomics, untargeted metabolomics, and sigmoid colonic biopsies for bulk RNAseq. Differential gene expression, differences in microbiota composition and metabolite abundance were determined. Gene and metabolite clusters were identified via weighted gene correlation network analysis and correlations with clinical and physiological parameters determined. RESULTS: PI-IBS (59% F, 46±2 yrs.) and HV (64% F, 42±2 yrs.) demographics were comparable. Mean IBS-symptom severity score was 227; 94% were non-constipation. 2-24h lactulose excretion was increased in PI-IBS, suggesting increased colonic permeability (4.4±0.5 mg vs. 2.6±0.3 mg, p=0.01). Colonic transit and sensory thresholds were similar between the two groups. Overall, expression of 2036 mucosal genes and 223 fecal metabolites were different, with changes more prominent in females. Fecal N-acetylputrescine was increased in PI-IBS and associated with colonic permeability, worse diarrhea, and negatively correlated with abundance of Collinsella aerofaciens. Histamine and N-acetyl histamine positively associated with 2-24 hr lactulose excretion. Eight weighted gene coexpression modules significantly correlated with phenotypes (sex, stool frequency, colonic permeability, transit). CONCLUSIONS: Campylobacter PI-IBS patients demonstrate higher colonic permeability which associated with changes in polyamine and histamine metabolites. Female patients demonstrated greater molecular changes.

9.
BMC Med Educ ; 24(1): 736, 2024 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-38982429

RESUMO

BACKGROUND: Academic paper writing holds significant importance in the education of medical students, and poses a clear challenge for those whose first language is not English. This study aims to investigate the effectiveness of employing large language models, particularly ChatGPT, in improving the English academic writing skills of these students. METHODS: A cohort of 25 third-year medical students from China was recruited. The study consisted of two stages. Firstly, the students were asked to write a mini paper. Secondly, the students were asked to revise the mini paper using ChatGPT within two weeks. The evaluation of the mini papers focused on three key dimensions, including structure, logic, and language. The evaluation method incorporated both manual scoring and AI scoring utilizing the ChatGPT-3.5 and ChatGPT-4 models. Additionally, we employed a questionnaire to gather feedback on students' experience in using ChatGPT. RESULTS: After implementing ChatGPT for writing assistance, there was a notable increase in manual scoring by 4.23 points. Similarly, AI scoring based on the ChatGPT-3.5 model showed an increase of 4.82 points, while the ChatGPT-4 model showed an increase of 3.84 points. These results highlight the potential of large language models in supporting academic writing. Statistical analysis revealed no significant difference between manual scoring and ChatGPT-4 scoring, indicating the potential of ChatGPT-4 to assist teachers in the grading process. Feedback from the questionnaire indicated a generally positive response from students, with 92% acknowledging an improvement in the quality of their writing, 84% noting advancements in their language skills, and 76% recognizing the contribution of ChatGPT in supporting academic research. CONCLUSION: The study highlighted the efficacy of large language models like ChatGPT in augmenting the English academic writing proficiency of non-native speakers in medical education. Furthermore, it illustrated the potential of these models to make a contribution to the educational evaluation process, particularly in environments where English is not the primary language.


Assuntos
Inteligência Artificial , Estudantes de Medicina , Redação , Humanos , China , Educação de Graduação em Medicina , Masculino , Feminino , Idioma
10.
Transl Cancer Res ; 13(6): 3062-3074, 2024 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-38988941

RESUMO

Background: Acute myeloid leukemia (AML) is the second most frequently occurring type of leukemia in adults. Despite breakthroughs in genetics, the prognosis of AML patients remains dismal. The aim of this study is to find new therapeutic targets and diagnostic markers for AML and to explore their mechanisms of action. Methods: The expression patterns of integrin subunit alpha M (ITGAM) were investigated across different cell types using the Human Protein Atlas (HPA) database. The ITGAM levels across cancer types were analyzed using the Gene Expression Profiling Interactive Analysis (GEPIA) database. Prognostic correlations in AML individuals were evaluated using The Cancer Genome Atlas (TGCA) database. ITGAM-associated functions were evaluated by Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses. The AML cells were transfected with short-hairpin RNA targeting ITGAM or a control, and subsequently subjected to analysis in order to ascertain the impact of ITGAM on proliferation and apoptosis. Results: The expression of ITGAM was significantly higher in the AML patient samples compared to the control samples. High ITGAM expression was significantly associated with poor overall survival (OS). The knockdown of ITGAM in the AML cells resulted in a decrease in proliferation and an increase in apoptosis. This was accompanied by cell cycle arrest at the G1 phase and a downregulation of protein production for cyclin D1, cyclin E1, cyclin-dependent kinase 2 (CDK2), and cyclin-dependent kinase 4 (CDK4). A pathway analysis and a western blot analysis revealed that ITGAM positively regulated mitogen-activated protein kinase (MAPK) signaling by silencing attenuated p38 MAPK (P38), c-Jun N-terminal kinase (JNK), and extracellular signal-regulated kinase (ERK) phosphorylation, while the total protein levels remained unchanged. Conclusions: ITGAM can serve as a potential prognostic biomarker and therapeutic target for AML. ITGAM production was elevated in AML and indicated poor survival. Silencing ITGAM suppressed AML cell viability and induced apoptosis by blocking cell cycle progression, likely by impeding the activation of the MAPK pathway. Further investigations that directly target the ITGAM-MAPK axis may offer novel strategies for mitigating AML pathogenesis and overcoming chemotherapy resistance.

11.
Abdom Radiol (NY) ; 2024 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-38995401

RESUMO

PURPOSE: To assess the diagnostic potential of whole-tumor histogram analysis of multiple non-Gaussian diffusion models for differentiating cervical cancer (CC) aggressive status regarding of pathological types, differentiation degree, stage, and p16 expression. METHODS: Patients were enrolled in this prospective single-center study from March 2022 to July 2023. Diffusion-weighted images (DWI) were obtained including 15 b-values (0 ~ 4000 s/mm2). Diffusion parameters derived from four non-Gaussian diffusion models including continuous-time random-walk (CTRW), diffusion-kurtosis imaging (DKI), fractional order calculus (FROC), and intravoxel incoherent motion (IVIM) were calculated, and their histogram features were analyzed. To select the most significant features and establish predictive models, univariate analysis and multivariate logistic regression were performed. Finally, we evaluated the diagnostic performance of our models by using receiver operating characteristic (ROC) analyses. RESULTS: 89 women (mean age, 55 ± 11 years) with CC were enrolled in our study. The combined model, which incorporated the CTRW, DKI, FROC, and IVIM diffusion models, offered a significantly higher AUC than that from any individual models (0.836 vs. 0.664, 0.642, 0.651, 0.649, respectively; p < 0.05) in distinguishing cervical squamous cell cancer from cervical adenocarcinoma. To distinguish tumor differentiation degree, except the combined model showed a better predictive performance compared to the DKI model (AUC, 0.839 vs. 0.697, respectively; p < 0.05), no significant differences in AUCs were found among other individual models and combined model. To predict the International Federation of Gynecology and Obstetrics (FIGO) stage, only DKI and FROC model were established and there was no significant difference in predictive performance among different models. In terms of predicting p16 expression, the predictive ability of DKI model is significantly lower than that of FROC and combined model (AUC, 0.693 vs. 0.850, 0.859, respectively; p < 0.05). CONCLUSION: Multiple non-Gaussian diffusion models with whole-tumor histogram analysis show great promise to assess the aggressive status of CC.

12.
Water Environ Res ; 96(7): e11062, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38982838

RESUMO

Karst groundwater, which is one of most important drinking water sources, is vulnerable to be polluted as its closed hydraulic relation with surface water. Thus, it is very important to identify the groundwater source to control groundwater pollution. The Pearson correlation coefficient among major ions (Na + K+, Ca2+, Mg2+, HCO3 -, SO4 2-, and Cl-) was employed to deduce the groundwater types in Zhong Liang Mountain, Southwest China. Then, the combined method of principal component analysis and cluster analysis were employed to identify the groundwater sources in a typical karst region of southwest China. The results shown that (1) the high positive correlation between cations and anions indicated the water-rock reaction of Ca-HCO3, Ca-SO4, (Na + K)-Cl, and Mg-SO4. (2) The major two principal components that would represent water-rock reaction of CaSO4 and Ca-HCO3 would, respectively, explain 60.41% and 31.80% of groundwater information. (3) Based on the two principal components, 33 groundwater samples were clustered into eight groups through hierarchical clustering, each group has similar water-rock reaction. The findings would be employed to forecast the surge water, that was an important work for tunnel construction and operation. PRACTITIONER POINTS: The components of groundwater was highly correlated with water-rock reaction. The principal component analysis screens the types of groundwater. The cluster analysis identifies the groundwater sources.


Assuntos
Água Subterrânea , China , Água Subterrânea/química , Monitoramento Ambiental , Análise por Conglomerados , Poluentes Químicos da Água/análise , Análise de Componente Principal , Fenômenos Geológicos
13.
Funct Integr Genomics ; 24(4): 122, 2024 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-38980439

RESUMO

Renal cell carcinoma (RCC) is a malignant tumor originating from the epithelial cells of the renal tubules. The clear cell RCC subtype is closely linked to a poor prognosis due to its rapid progression. Circular RNA (circRNA) is a novel class of regulatory RNA molecules that play a role in the development of ccRCC, although their functions have not been fully elucidated. In this study, we identified a significant downregulation of circ-IP6K2 in ccRCC tissues based on data from the GSE100186 dataset. The decreased expression of circ-IP6K2 correlated with the progression of TNM stage and histological grade, and was also associated with decreased overall survival rates in ccRCC patients. Moreover, our findings revealed that circ-IP6K2 expression suppressed proliferation, migration, and invasion capabilities in vitro, and inhibited xenograft growth in vivo. Mechanistically, circ-IP6K2 acted as a sponge for miR-1292-5p in ccRCC cells, which in turn targeted the 3'UTR of CAMK2N1, leading to a decrease in its expression. CAMK2N1 was identified as a tumor suppressor that negatively regulated the ß-catenin/c-Myc oncogenic signaling pathway. Additionally, we confirmed a positive correlation between the expression of circ-IP6K2 and CAMK2N1 in ccRCC. Circ-IP6K2 functions to impede the progression of ccRCC by modulating the miR-1292-5p/CAMK2N1 axis. These findings shed new light on the molecular mechanisms driving ccRCC progression and suggest potential therapeutic targets for the treatment of ccRCC.


Assuntos
Carcinoma de Células Renais , Neoplasias Renais , MicroRNAs , RNA Circular , Humanos , MicroRNAs/genética , MicroRNAs/metabolismo , Carcinoma de Células Renais/genética , Carcinoma de Células Renais/patologia , Carcinoma de Células Renais/metabolismo , RNA Circular/genética , RNA Circular/metabolismo , Neoplasias Renais/genética , Neoplasias Renais/patologia , Neoplasias Renais/metabolismo , Animais , Linhagem Celular Tumoral , Camundongos , Transdução de Sinais , Proliferação de Células , Regulação Neoplásica da Expressão Gênica , Masculino , Feminino , Camundongos Nus , Movimento Celular , Progressão da Doença
14.
Int J Biol Macromol ; 275(Pt 2): 133718, 2024 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-38977052

RESUMO

The polysaccharide glucan was extracted from Gastrodia elata Blume, and its structural characterizations and beneficial effects against acute dextran sulfate sodium (DSS)-induced ulcerative colitis were investigated. The results showed that a polysaccharide GP with a molecular weight of 811.0 kDa was isolated from G. elata Blume. It had a backbone of α-D-1,4-linked glucan with branches of α-d-glucose linked to the C-6 position. GP exhibited protective effects against DSS-induced ulcerative colitis, and reflected in ameliorating weight loss and pathological damages in mice, increasing colon length, inhibiting the expression of inflammatory cytokines tumor necrosis factor-α (TNF-α) and interleukin-1ß (IL-1ß), decreasing the levels of inflammatory related proteins NLRP3 and ASC, and elevating the anti-inflammatory cytokine interleukin-10 (IL-10) level in mouse colon tissues. GP supplementation also reinforced the intestinal barrier by promoting the expression of ZO-1, Occludin, and MUC2 of colon tissues, and positively regulated intestinal microbiota. Thus, GP treatment possessed a significant improvement in ulcerative colitis in mice, and it was expected to be developed as a functional food.

15.
Zhongguo Dang Dai Er Ke Za Zhi ; 26(7): 690-694, 2024 Jul 15.
Artigo em Chinês | MEDLINE | ID: mdl-39014944

RESUMO

OBJECTIVES: To investigate the application of endoscopic retrograde cholangiopancreatography (ERCP) in children and the risk factors for post-ERCP pancreatitis (PEP). METHODS: A retrospective analysis was conducted on the clinical data of 66 children, aged ≤16 years, who underwent ERCP for pancreaticobiliary diseases at the Gastrointestinal Endoscopy Center of the Second Affiliated Hospital of Kunming Medical University from September 2013 to September 2023. The incidence rate of PEP and the risk factors for the development of PEP were analyzed. RESULTS: A total of 78 ERCP procedures were performed on 66 children, with 5 diagnostic ERCPs, 69 therapeutic ERCPs, and 4 failed procedures. The success rate of ERCP operations was 95% (74/78). There were 17 cases of PEP in total, with an incidence rate of 22%. In the PEP group, the proportion of children with normal preoperative bilirubin and the proportion of guidewire insertion into the pancreatic duct during surgery were higher than in the non-PEP group (P<0.05). The multivariate logistic regression analysis showed that guidewire insertion into the pancreatic duct was an independent risk factor for PEP (P<0.05). CONCLUSIONS: With the increasing application of ERCP in children with pancreaticobiliary diseases, it is important to select an appropriate intubation technique during surgery to avoid blindly entering the guidewire into the pancreatic duct and reduce the occurrence of PEP.


Assuntos
Colangiopancreatografia Retrógrada Endoscópica , Pancreatite , Humanos , Colangiopancreatografia Retrógrada Endoscópica/efeitos adversos , Criança , Masculino , Pancreatite/etiologia , Pancreatite/prevenção & controle , Feminino , Fatores de Risco , Estudos Retrospectivos , Pré-Escolar , Adolescente , Modelos Logísticos , Lactente
17.
Foods ; 13(12)2024 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-38928779

RESUMO

Curcumin is a naturally occurring hydrophobic polyphenolic compound with a rapid metabolism, poor absorption, and low stability, which severely limits its bioavailability. Here, we employed a starch-protein-based nanoparticle approach to improve the curcumin bioavailability. This study focused on synthesizing nanoparticles with a zein "core" and a carboxymethylated short-chain amylose (CSA) "shell" through anti-solvent precipitation for delivering curcumin. The zein@CSA core-shell nanoparticles were extensively characterized for physicochemical properties, structural integrity, ionic stability, in vitro digestibility, and antioxidant activity. Fourier-transform infrared (FTIR) spectroscopy indicates nanoparticle formation through hydrogen-bonding, hydrophobic, and electrostatic interactions between zein and CSA. Zein@CSA core-shell nanoparticles exhibited enhanced stability in NaCl solution. At a zein-to-CSA ratio of 1:1.25, only 15.7% curcumin was released after 90 min of gastric digestion, and 66% was released in the intestine after 240 min, demonstrating a notable sustained release effect. Furthermore, these nanoparticles increased the scavenging capacity of the 1,1-diphenyl-2-picrylhydrazyl (DPPH•) free radical compared to those composed solely of zein and were essentially nontoxic to Caco-2 cells. This research offers valuable insights into curcumin encapsulation and delivery using zein@CSA core-shell nanoparticles.

18.
Anal Chem ; 96(26): 10860-10869, 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38889184

RESUMO

Single-molecule localization microscopy (SMLM) requires high-intensity laser irradiation, typically exceeding kW/cm2, to yield a sufficient photon count. However, this intense visible light exposure incurs substantial cellular toxicity, hindering its use in living cells. Here, we developed a class of near-infrared (NIR) spontaneously blinking fluorophores for SMLM. These NIR fluorophores are a combination of rhodamine spirolactams and merocyanine derivatives, where the rhodamine spirolactam component converts between a bright and dark state based on pH-dependent spirocyclization and merocyanine derivatives shift the excitation wavelength into the infrared. Single-molecule characterizations demonstrated their potential for SMLM. At a moderate power density of 3.93 kW/cm2, these probes exhibit duty cycle as low as 0.18% and an emission rate as high as 26,700 photons/s. Phototoxicity assessment under single-molecule imaging conditions reveals that NIR illumination (721 nm) minimizes harm to living cells. Employing these NIR fluorophores, we successfully captured time-lapse super-resolution tracking of mitochondria at a Fourier ring correlation (FRC) resolution of 69.4 nm and reconstructed the ultrastructures of endoplasmic reticulum (ER) in living cells.


Assuntos
Corantes Fluorescentes , Raios Infravermelhos , Corantes Fluorescentes/química , Humanos , Células HeLa , Indóis/química , Rodaminas/química , Microscopia de Fluorescência , Sobrevivência Celular/efeitos dos fármacos , Mitocôndrias , Benzopiranos
19.
ACS Appl Mater Interfaces ; 16(26): 33169-33181, 2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-38915234

RESUMO

Inducing immunogenic cell death (ICD) is a promising strategy for cancer immunotherapy. Shikonin (SHK), a naphthoquinone compound from Lithospermum erythrorhizon, can stimulate antitumor immunity by inducing ICD. Nevertheless, the immunogenicity of tumor cells killed by SHK is weak. Endoplasmic reticulum (ER) stress is an important intracellular pathway of the ICD effect. Curcumin (CUR) can directly induce ER stress by disrupting Ca2+ homeostasis, which might enhance SHK-induced ICD effect. A self-delivery ICD effect nanobooster (CS-PEG NPs) was developed by the self-assembly of SHK (ICD inducer) and CUR (ICD enhancer) with the assistance of DSPE-PEG2K for cancer chemoimmunotherapy. CS-PEG NPs possessed effective CT26 tumor cell cellular uptake and tumor accumulation ability. Moreover, enhanced cytotoxicity against tumor cells and apoptosis promotion were achieved due to the synergistic effect of CUR and SHK. Notably, CS-PEG NPs induced obvious Ca2+ homeostasis disruption, ER stress, and ICD effect. Subsequently, the neoantigens produced by the robust ICD effect in vivo promoted dendritic cell maturation, which further recruited and activated cytotoxic T lymphocytes. Superior antitumor efficacy and systemic antitumor immunity were observed in the CT26-bearing BALB/c mouse model without side effects in major organs. This study offers a promising self-delivery nanobooster to induce strong ICD effect and antitumor immunity for cancer chemoimmunotherapy.


Assuntos
Curcumina , Estresse do Retículo Endoplasmático , Morte Celular Imunogênica , Imunoterapia , Camundongos Endogâmicos BALB C , Naftoquinonas , Animais , Naftoquinonas/química , Naftoquinonas/farmacologia , Morte Celular Imunogênica/efeitos dos fármacos , Camundongos , Curcumina/química , Curcumina/farmacologia , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Linhagem Celular Tumoral , Nanopartículas/química , Humanos , Neoplasias/tratamento farmacológico , Neoplasias/terapia , Neoplasias/imunologia , Neoplasias/patologia , Antineoplásicos/química , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Feminino
20.
Nat Commun ; 15(1): 5151, 2024 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-38886382

RESUMO

RNA Polymerase (RNAP) II transcription on non-coding repetitive satellite DNAs plays an important role in chromosome segregation, but a little is known about the regulation of satellite transcription. We here show that Topoisomerase I (TopI), not TopII, promotes the transcription of α-satellite DNAs, the main type of satellite DNAs on human centromeres. Mechanistically, TopI localizes to centromeres, binds RNAP II and facilitates RNAP II elongation. Interestingly, in response to DNA double-stranded breaks (DSBs), α-satellite transcription is dramatically stimulated in a DNA damage checkpoint-independent but TopI-dependent manner, and these DSB-induced α-satellite RNAs form into strong speckles in the nucleus. Remarkably, TopI-dependent satellite transcription also exists in mouse 3T3 and Drosophila S2 cells and in Drosophila larval imaginal wing discs and tumor tissues. Altogether, our findings herein reveal an evolutionally conserved mechanism with TopI as a key player for the regulation of satellite transcription at both cellular and animal levels.


Assuntos
Centrômero , DNA Topoisomerases Tipo I , DNA Satélite , RNA Polimerase II , Transcrição Gênica , Animais , DNA Satélite/genética , DNA Satélite/metabolismo , Humanos , Centrômero/metabolismo , Camundongos , DNA Topoisomerases Tipo I/metabolismo , DNA Topoisomerases Tipo I/genética , RNA Polimerase II/metabolismo , RNA Polimerase II/genética , Quebras de DNA de Cadeia Dupla , Drosophila/genética , Drosophila/metabolismo , Drosophila melanogaster/genética , Drosophila melanogaster/metabolismo , Evolução Molecular
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