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1.
IEEE Trans Image Process ; 33: 3227-3241, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38691435

RESUMO

The statistical regularities of natural images, referred to as natural scene statistics, play an important role in no-reference image quality assessment. However, it has been widely acknowledged that screen content images (SCIs), which are typically computer generated, do not hold such statistics. Here we make the first attempt to learn the statistics of SCIs, based upon which the quality of SCIs can be effectively determined. The underlying mechanism of the proposed approach is based upon the mild assumption that the SCIs, which are not physically acquired, still obey certain statistics that could be understood in a learning fashion. We empirically show that the statistics deviation could be effectively leveraged in quality assessment, and the proposed method is superior when evaluated in different settings. Extensive experimental results demonstrate the Deep Feature Statistics based SCI Quality Assessment (DFSS-IQA) model delivers promising performance compared with existing NR-IQA models and shows a high generalization capability in the cross-dataset settings. The implementation of our method is publicly available at https://github.com/Baoliang93/DFSS-IQA.

2.
Artigo em Inglês | MEDLINE | ID: mdl-38684053

RESUMO

Metal-oxide-semiconductor field-effect transistors as basic electronic devices of integrated circuits have been greatly developed and widely used in the past decades. However, as the thickness of the conducting channel decreases, the interface electronic scattering between the gate oxide layer and the channel significantly impacts the performance of the transistor. To address this issue, van der Waals heterojunction field-effect transistors (vdWJFETs) have been proposed using two-dimensional semiconductors, which utilize the built-in electric field at the sharp van der Waals interface to regulate the channel conductance without the need of a complex gate oxide layer. In this study, a novel dual-junction vdWJFET composed of a MoS2 channel and a Te nanosheet gate has been developed. This device achieves an ultralow subthreshold swing (SS) and an extremely low current hysteresis, greatly surpassing the single-junction vdWJFET. In the transistor, the SS decreases from 475.04 to 68.3 mV dec-1, nearly approaching the theoretical limit of 60 mV dec-1 at room temperature. The pinch-off voltage (Vp) decreases from -4.5 to -0.75 V, with a current hysteresis of ∼10 mV and a considerable field-effect mobility (µ) of 36.43 cm2 V-1 s-1. The novel dual-junction vdWJFET provides a new approach to realize a transistor with a theoretical ideal SS and a negligible current hysteresis toward low-power electronic applications.

3.
Nature ; 625(7996): 697-702, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38172639

RESUMO

Body-centred cubic refractory multi-principal element alloys (MPEAs), with several refractory metal elements as constituents and featuring a yield strength greater than one gigapascal, are promising materials to meet the demands of aggressive structural applications1-6. Their low-to-no tensile ductility at room temperature, however, limits their processability and scaled-up application7-10. Here we present a HfNbTiVAl10 alloy that shows remarkable tensile ductility (roughly 20%) and ultrahigh yield strength (roughly 1,390 megapascals). Notably, these are among the best synergies compared with other related alloys. Such superb synergies derive from the addition of aluminium to the HfNbTiV alloy, resulting in a negative mixing enthalpy solid solution, which promotes strength and favours the formation of hierarchical chemical fluctuations (HCFs). The HCFs span many length scales, ranging from submicrometre to atomic scale, and create a high density of diffusive boundaries that act as effective barriers for dislocation motion. Consequently, versatile dislocation configurations are sequentially stimulated, enabling the alloy to accommodate plastic deformation while fostering substantial interactions that give rise to two unusual strain-hardening rate upturns. Thus, plastic instability is significantly delayed, which expands the plastic regime as ultralarge tensile ductility. This study provides valuable insights into achieving a synergistic combination of ultrahigh strength and large tensile ductility in MPEAs.

4.
Surgery ; 175(4): 1140-1146, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38290878

RESUMO

BACKGROUND: Hand-sewn anastomosis and stapled anastomosis are the 2 main types of gastrojejunal anastomotic methods in pancreaticoduodenectomy. There is ongoing debate regarding the most effective anastomotic method for reducing delayed gastric emptying after pancreaticoduodenectomy. This study aims to identify factors that influence delayed gastric emptying after pancreaticoduodenectomy and assess the impact of different anastomotic methods on delayed gastric emptying. METHODS: The study included 1,077 patients who had undergone either hand-sewn anastomosis (n = 734) or stapled anastomosis (n = 343) during pancreaticoduodenectomy between December 2016 and November 2021 at our department. We retrospectively analyzed the clinical data, and a 1:1 propensity score matching was performed to balance confounding variables. RESULTS: After propensity score matching, 320 patients were included in each group. Compared with the stapled anastomosis group, the hand-sewn anastomosis group had a significantly lower incidence of delayed gastric emptying (28 [8.8%] vs 55 [17.2%], P = .001) and upper gastrointestinal tract bleeding (6 [1.9%] vs 17 [5.3%], P = .02). Additionally, the hand-sewn anastomosis group had a significantly reduced postoperative length of stay and lower hospitalization expenses. However, the hand-sewn anastomosis group had a significantly longer operative time, which was consistent with the analysis before propensity score matching. Logistic regression analysis showed that stapled anastomosis, intra-abdominal infection, and clinically relevant postoperative pancreatic fistula were independent prognostic factors for delayed gastric emptying. CONCLUSION: Hand-sewn anastomosis was associated with a lower incidence rate of clinically relevant delayed gastric emptying after pancreaticoduodenectomy. Stapled anastomosis, intra-abdominal infection, and clinically relevant postoperative pancreatic fistula could increase the incidence of postoperative clinically relevant delayed gastric emptying. Hand-sewn anastomosis should be considered by surgeons to reduce the occurrence of postoperative delayed gastric emptying and improve patient outcomes.


Assuntos
Gastroparesia , Infecções Intra-Abdominais , Humanos , Pancreaticoduodenectomia/efeitos adversos , Pancreaticoduodenectomia/métodos , Estudos Retrospectivos , Gastroparesia/epidemiologia , Gastroparesia/etiologia , Gastroparesia/prevenção & controle , Fístula Pancreática/epidemiologia , Fístula Pancreática/etiologia , Fístula Pancreática/prevenção & controle , Anastomose Cirúrgica/efeitos adversos , Anastomose Cirúrgica/métodos , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/prevenção & controle , Infecções Intra-Abdominais/complicações , Esvaziamento Gástrico , Resultado do Tratamento
5.
Cell Biochem Biophys ; 82(1): 291-302, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38082173

RESUMO

This experiment successfully isolated the rat colonic epithelial cells and established a TNF-α-induced intestinal inflammation model. Western Blot was used to detect the related protein expression levels of the MAPKs signaling pathway. QPCR technology was used to detect the expression of aquaporins, intestinal mucosal repair factor, and inflammatory factors. The results show that 25 µM ß-carotene pretreatment at 24 h can inhibit MAPKs signaling pathway activated by TNF-α, change the relative mRNA expression of inflammatory cytokines, intestinal mucosal repair factors, and aquaporins, and the phosphorylated protein expression of p38, ERK, and NF-κB were attenuated to reduce inflammatory damage. After inhibiting p38 and ERK, the effect of ß-carotene was reduced significantly (P < 0.05). In conclusion, ß-carotene can alleviate the abnormal expression of aquaporins caused by inflammation through the MAPKs signaling pathway. This is for ß-carotene as a functional nutrient that provides new insights.


Assuntos
Aquaporinas , Fator de Necrose Tumoral alfa , Ratos , Animais , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/metabolismo , beta Caroteno/farmacologia , beta Caroteno/metabolismo , Transdução de Sinais , NF-kappa B/metabolismo , Células Epiteliais/metabolismo , Inflamação/induzido quimicamente , Inflamação/metabolismo , Aquaporinas/metabolismo
6.
Int J Nanomedicine ; 18: 6667-6687, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38026520

RESUMO

Purpose: Sonodynamic therapy (SDT), with its high tissue penetration and noninvasive advantages, represents an emerging approach to eradicating solid tumors. However, the outcomes of SDT are typically hampered by the low oxygen content and immunosuppression in the tumor microenvironment (TME). Accordingly, we constructed a cascade nanoplatform to regulate the TME and improve the anti-tumor efficiency of SDT. Methods: In this study, we rationally design cascade nanoplatform by incorporating immunostimulant hyaluronic acid (HA) and sonosensitizer chlorin e6 (Ce6) on the polydopamine nanocarrier that is pre-doped with platinum nanozymes (designated Ce6/Pt@PDA-HA, PPCH). Results: The cascade reactions of PPCH are evidenced by the results that HA exhibits reversing immunosuppressive that converts M2 macrophages into M1 macrophages in situ, while producing H2O2, and then platinum nanozymes further catalyze the H2O2 to produce O2, and O2 produces abundant singlet oxygen (1O2) under the action of Ce6 and low-intensity focused ultrasound (LIFU), resulting in a domino effect and further amplifying the efficacy of SDT. Due to its pH responsiveness and mitochondrial targeting, PPCH effectively accumulates in tumor cells. Under LIFU irradiation, PPCH effectively reverses immunosuppression, alleviates hypoxia in the TME, enhances reactive oxygen species (ROS) generation, and enhances SDT efficacy for eliminating tumor cells in vivo and in vitro. Meanwhile, an in vivo dual-modal imaging including fluorescence and photoacoustic imaging achieves precise tumor diagnosis. Conclusion: This cascade nanoplatform will provide a promising strategy for enhancing SDT eradication against tumors by modulating immunosuppression and relieving hypoxia.


Assuntos
Nanopartículas , Porfirinas , Terapia por Ultrassom , Humanos , Terapia por Ultrassom/métodos , Peróxido de Hidrogênio , Platina , Linhagem Celular Tumoral , Porfirinas/farmacologia , Porfirinas/química , Espécies Reativas de Oxigênio , Hipóxia , Nanopartículas/química , Microambiente Tumoral
7.
BMC Cancer ; 23(1): 790, 2023 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-37612635

RESUMO

OBJECTIVE: To improve prediction, the AJCC staging system was revised to be consistent with upfront surgery (UFS) and neoadjuvant therapy (NAT) for PDAC. BACKGROUND: The AJCC staging system was designed for patients who have had UFS for PDAC, and it has limited predictive power for patients receiving NAT. METHODS: We examined 146 PDAC patients who had resection after NAT and 1771 who had UFS at Changhai Hospital between 2012 and 2021. The clinicopathological factors were identified using Cox proportional regression analysis, and the Neoadjuvant Therapy Compatible Prognostic (NATCP) staging was developed based on these variables. Validation was carried out in the prospective NAT cohort and the SEER database. The staging approach was compared to the AJCC staging system regarding predictive accuracy. RESULTS: The NAT cohort's multivariate analysis showed that tumor differentiation and the number of positive lymph nodes independently predicted OS. The NATCP staging simplified the AJCC stages, added tumor differentiation, and restaged the disease based on the Kaplan-Meier curve survival differences. The median OS for NATCP stages IA, IB, II, and III was 31.7 months, 25.0 months, and 15.8 months in the NAT cohort and 30.1 months, 22.8 months, 18.3 months, and 14.1 months in the UFS cohort. Compared to the AJCC staging method, the NATCP staging system performed better and was verified in the validation cohort. CONCLUSIONS: Regardless of the use of NAT, NATCP staging demonstrated greater predictive abilities than the existing AJCC staging approach for resected PDAC and may facilitate clinical decision-making based on accurate prediction of patients' OS.


Assuntos
Carcinoma Ductal Pancreático , Neoplasias Pancreáticas , Humanos , Terapia Neoadjuvante , Prognóstico , Estudos Prospectivos , Neoplasias Pancreáticas/cirurgia , Carcinoma Ductal Pancreático/cirurgia , Neoplasias Pancreáticas
8.
Int J Nanomedicine ; 18: 2275-2293, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37159806

RESUMO

Introduction: In order to diagnose and treat papillary thyroid carcinoma (PTC) accurately, phase-transition nanoparticles, P@IP-miRNA (PFP@IR780/PLGA-bPEI-miRNA338-3p), was engineered. The nanoparticles (NPs) can target the tumor cells, realize the multimodal imaging, and provide sonodynamic-gene therapy for PTC. Methods: P@IP-miRNA NPs were synthesized through double emulsification method, and miRNA338-3p was attached to the surface of the NPs by electrostatic adsorption. The characterization of NPs was detected to screen out qualified nanoparticles. In vitro, laser confocal microscopy and flow cytometry were used to detect the targeting and subcellular localization of NPs. Western blot, qRT-PCR, and immunofluorescence were used to detect the ability to transfect miRNA. CCK8 kit, laser confocal microscopy and flow cytometry were used to detect the inhibition on TPC-1 cells. In vivo experiments were performed based on tumor-bearing nude mice. The efficacy of combined treatment by NPs was comprehensively evaluated, and the multimodal imaging ability of NPs in vivo and in vitro was detected. Results: P@IP-miRNA NPs were successfully synthesized which have spherical shape, uniform size, good dispersion and positive potential. The encapsulation rate of IR780 was (82.58±3.92) %, the drug loading rate was (6.60±0.32) %, and the adsorption capacity of miRNA338-3p was 41.78 µg/mg. NPs have excellent tumor targeting ability, miRNA transfection ability, ROS production ability and multimodal imaging ability in vivo and in vitro. The antitumor effect of combined treatment group was the best, and the efficacy was better than that of single factor treatment group, and the difference was statistically significant. Conclusion: P@IP-miRNA NPs can realize multimodal imaging and sonodynamic-gene therapy, providing a new idea for accurate diagnosis and treatment of PTC.


Assuntos
Carcinoma Papilar , Nanopartículas , Neoplasias da Glândula Tireoide , Animais , Camundongos , Câncer Papilífero da Tireoide , Camundongos Nus , Terapia Genética , Neoplasias da Glândula Tireoide/diagnóstico por imagem , Neoplasias da Glândula Tireoide/terapia
9.
BJS Open ; 7(3)2023 05 05.
Artigo em Inglês | MEDLINE | ID: mdl-37146207

RESUMO

BACKGROUND: The superior mesenteric artery-first approach has been proved superior in pancreatoduodenectomy compared with the standard procedure. It is unclear whether similar benefits could be obtained in distal pancreatectomy with celiac axis resection. METHODS: Perioperative and survival outcomes of patients who underwent distal pancreatectomy with celiac axis resection with the modified artery-first approach or traditional approach between January 2012 and September 2021 were compared. RESULTS: The entire cohort comprised 106 patients (modified artery-first approach, n = 35; traditional approach, n = 71). The most common complication was postoperative pancreatic fistula (n = 18, 17.0 per cent), followed by ischaemic complications (n = 17, 16.0 per cent) and surgical site infection (n = 15, 14.0 per cent). Intraoperative blood loss (400 versus 600 ml, P = 0.017) and intraoperative transfusion rate (8.6 versus 29.6 per cent, P = 0.015) were lower in the modified artery-first approach group compared with the traditional approach group. A higher number of harvested lymph nodes (18 versus 13, P = 0.030) and R0 resection rate (88.6 versus 70.4 per cent, P = 0.038) and a lower incidence of ischaemic complications (5.7 versus 21.1 per cent, P = 0.042) was observed in the modified artery-first approach group compared with the traditional approach group. In multivariable analysis, the modified artery-first approach (OR 0.006, 95 per cent c.i., 0 to 0.447; P = 0.020) was protective against ischaemic complications. CONCLUSIONS: Compared with the traditional approach, the modified artery-first approach was associated with lower blood loss and fewer ischaemic complications, and a higher number of harvested lymph nodes and R0 resection rate. Thus, it might improve the safety, staging and prognosis of distal pancreatectomy with celiac axis resection for pancreatic cancer.


Assuntos
Pancreatectomia , Neoplasias Pancreáticas , Humanos , Pancreatectomia/efeitos adversos , Pancreatectomia/métodos , Artéria Celíaca/cirurgia , Artéria Celíaca/patologia , Neoplasias Pancreáticas/patologia , Pâncreas/cirurgia , Pancreaticoduodenectomia/efeitos adversos
10.
Microbiome ; 11(1): 41, 2023 03 03.
Artigo em Inglês | MEDLINE | ID: mdl-36869365

RESUMO

BACKGROUND: Nutrition drives immunity and health in animals, and maternal immunity benefits offspring. In our previous study, a nutritional intervention strategy was found to promote the immunity of hens, which subsequently improved immunity and growth in offspring chicks. Maternal effects clearly exist, but how are mothers' immune advantages transferred to their offspring, and how do they benefit them? RESULTS: Here, we traced the beneficial effects back to the process of egg formation in the reproductive system, and we focused on the embryonic intestinal transcriptome and development, as well as on maternal microbial transfer in offspring. We found that maternal nutritional intervention benefits maternal immunity, egg hatching, and offspring growth. The results of protein and gene quantitative assays showed that the transfer of immune factors into egg whites and yolks depends on maternal levels. Histological observations indicated that the promotion of offspring intestinal development begins in the embryonic period. Microbiota analyses suggested that maternal microbes transfer to the embryonic gut from the magnum to the egg white. Transcriptome analyses revealed that offspring embryonic intestinal transcriptome shifts are related to development and immunity. Moreover, correlation analyses showed that the embryonic gut microbiota is correlated with the intestinal transcriptome and development. CONCLUSIONS: This study suggests that maternal immunity positively influences offspring intestinal immunity establishment and intestinal development beginning in the embryonic period. Adaptive maternal effects might be accomplished via the transfer of relatively large amounts of maternal immune factors and by shaping of the reproductive system microbiota by strong maternal immunity. Moreover, reproductive system microbes may be useful resources for the promotion of animal health. Video Abstract.


Assuntos
Galinhas , Microbioma Gastrointestinal , Animais , Feminino , Humanos , Herança Materna , Desenvolvimento Infantil , Perfilação da Expressão Gênica
11.
Foods ; 12(5)2023 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-36900520

RESUMO

The lack of a bioaccessibility test for yak bone collagen hydrolysates (YBCH) limits their development as functional foods. In this study, simulated gastrointestinal digestion (SD) and absorption (SA) models were utilized to evaluate the bioaccessibility of YBCH for the first time. The variation in peptides and free amino acids was primarily characterized. There was no significant alteration in the concentration of peptides during the SD. The transport rate of peptides through the Caco-2 cell monolayers was 22.14 ± 1.58%. Finally, a total of 440 peptides were identified, more than 75% of them with lengths ranging from 7 to 15. The peptide identification indicated that about 77% of the peptides in the beginning sample still existed after the SD, and about 76% of the peptides in the digested YBCH could be observed after the SA. These results suggested that most peptides in the YBCH resist gastrointestinal digestion and absorption. After the in silico prediction, seven typical bioavailable bioactive peptides were screened out and they exhibited multi-type bioactivities in vitro. This is the first study to characterize the changes in peptides and amino acids in the YBCH during gastrointestinal digestion and absorption, and provides a foundation for analyzing the mechanism of YBCH's bioactivities.

13.
Eur Radiol ; 33(4): 2407-2414, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36472698

RESUMO

OBJECTIVES: To investigate the value of contrast-enhanced ultrasound (CEUS) combined with feeding artery ablation in the microwave ablation (MWA) of large solid benign thyroid nodules (LSBTNs) with a diameter ≥ 4 cm. METHODS: We retrospectively analyzed 122 patients with LSBTN ≥ 4 cm in diameter treated with MWA. During evaluations before and after MWA, 53 patients who underwent conventional ultrasound examination were classified as the routine group, and 69 patients who underwent CEUS combined with feeding artery ablation were classified as the union group. The differences in ablation energy required per milliliter (AERPM), complication rate, regrowth rate, and volume reduction rate (VRR) were compared between the two groups. RESULTS: The AERPM of the union group was significantly less than that of the routine group (956.3 ± 38.5 J/mL vs. 1025.9 ± 121.5 J/mL, p < 0.001). The complication rate of the routine group was significantly higher than that of the union group (13.2% vs. 2.9%, p = 0.031). The regrowth rate of the routine group (22.6%, 12/53) was significantly higher than that of the union group (7.2%, 5/69) (p = 0.015). At the 1st, 3rd, 6th, 12th, 18th, and 24th month after ablation, the mean VRRs of the routine group were significantly less than those of the union group, with p values of < 0.001, < 0.001, 0.002, 0.007, 0.013, and < 0.001, respectively. CONCLUSIONS: The application of CEUS combined with feeding artery ablation in the MWA of LSBTNs is helpful to reduce the regrowth rate, improve the ablation efficiency, and reduce bleeding. KEY POINTS: • CEUS combined with feeding artery ablation in MWA of LSBTNs is helpful to reduce regrowth rate. • CEUS combined with feeding artery ablation can help improve ablation efficiency than conventional ultrasound in LSBTNs. • CEUS combined with feeding artery ablation helps reduce the incidence of bleeding during MWA.


Assuntos
Ablação por Cateter , Nódulo da Glândula Tireoide , Humanos , Nódulo da Glândula Tireoide/diagnóstico por imagem , Nódulo da Glândula Tireoide/cirurgia , Micro-Ondas/uso terapêutico , Estudos Retrospectivos , Resultado do Tratamento , Artérias
14.
IEEE Trans Image Process ; 31: 6139-6151, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36112560

RESUMO

In this paper, we propose a no-reference (NR) image quality assessment (IQA) method via feature level pseudo-reference (PR) hallucination. The proposed quality assessment framework is rooted in the view that the perceptually meaningful features could be well exploited to characterize the visual quality, and the natural image statistical behaviors are exploited in an effort to deliver the accurate predictions. Herein, the PR features from the distorted images are learned by a mutual learning scheme with the pristine reference as the supervision, and the discriminative characteristics of PR features are further ensured with the triplet constraints. Given a distorted image for quality inference, the feature level disentanglement is performed with an invertible neural layer for final quality prediction, leading to the PR and the corresponding distortion features for comparison. The effectiveness of our proposed method is demonstrated on four popular IQA databases, and superior performance on cross-database evaluation also reveals the high generalization capability of our method. The implementation of our method is publicly available on https://github.com/Baoliang93/FPR.

15.
Cancer Res ; 82(22): 4153-4163, 2022 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-36098964

RESUMO

Menin is necessary for the formation of the menin/mixed lineage leukemia (MLL) complex and is recruited directly to chromatin. Menin is an important tumor suppressor in several cancer types, including lung cancer. Here, we investigated the role of MLL in menin-regulated lung tumorigenesis. Ablation of MLL suppressed KrasG12D-induced lung tumorigenesis in a genetically engineered mouse model. MLL deficiency decreased histone H3 lysine 4 trimethylation (H3K4me3) and subsequently suppressed expression of the Ras protein-specific guanine nucleotide-releasing factor 1 (Rasgrf1) gene. Rasgrf1 was essential for the GTP-bound active state of Kras and the activation of Kras downstream pathways as well as their cancer-promoting activities. MI-3, a small-molecule inhibitor targeting MLL, specifically inhibited the growth of Kras-mutated lung cancer cells in vitro and in vivo with minimal effect on wild-type Kras lung cancer growth. Together, these results demonstrate a novel tumor promoter function of MLL in mutant Kras-induced lung tumorigenesis and further indicate that specific blockade of the MLL-Rasgrf1 pathway may be a potential therapeutic strategy for the treatment of tumors containing Kras mutations. SIGNIFICANCE: Activation of mutant Kras is dependent on MLL-mediated epigenetic regulation of Rasgrf1, conferring sensitivity to small-molecule inhibition of MLL in Kras-driven lung cancer.


Assuntos
Epigênese Genética , Neoplasias Pulmonares , Proteína de Leucina Linfoide-Mieloide , ras-GRF1 , Animais , Camundongos , Transformação Celular Neoplásica/metabolismo , Epigênese Genética/genética , Epigênese Genética/fisiologia , Histona-Lisina N-Metiltransferase/genética , Histona-Lisina N-Metiltransferase/metabolismo , Leucemia/genética , Leucemia/patologia , Pulmão/metabolismo , Pulmão/patologia , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/etiologia , Neoplasias Pulmonares/genética , Proteína de Leucina Linfoide-Mieloide/genética , Proteína de Leucina Linfoide-Mieloide/metabolismo , ras-GRF1/genética , ras-GRF1/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Carcinogênese/genética , Carcinogênese/metabolismo , Mutação
16.
Int J Mol Sci ; 23(16)2022 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-36012259

RESUMO

Angiogenetic inhibitors are crucial in tumor therapy, and endogenous angiogenesis inhibitors have attracted considerable attention due to their effectiveness, safety, and multi-targeting ability. Arresten and canstatin, which have anti-angiogenesis effects, are the c-terminal fragments of the α1 and α2 chains of type IV collagen, respectively. In this study, human arresten and canstatin were recombinantly expressed in Escherichia coli (E. coli), and their effects on the proliferation, migration and tube formation of human umbilical vein endothelial cells (HUVECs) were evaluated. Regarding the cell cycle distribution test and 5-ethynyl-2'-deoxyuridine (EdU) assays, arresten and canstatin could repress the proliferation of HUVECs at a range of concentrations. Transwell assay indicated that the migration of HUVECs was significantly decreased in the presence of arresten and canstatin, while tube formation assays suggested that the total tube length and junction number of HUVECs were significantly inhibited by these two proteins; moreover, they could also reduce the expression of vascular endothelial growth factor (VEGF) and the phosphorylation levels of PI3K and Akt, which indicated that the activation of the 3-kinase/serine/threonine-kinase (PI3K/Akt) signaling pathway was inhibited. These findings may have important implications for the soluble recombinant expression of human arresten and canstatin, and for the related therapy of cancer.


Assuntos
Inibidores da Angiogênese , Fosfatidilinositol 3-Quinases , Proteínas Proto-Oncogênicas c-akt , Inibidores da Angiogênese/farmacologia , Movimento Celular , Proliferação de Células , Colágeno Tipo IV/farmacologia , Escherichia coli/metabolismo , Células Endoteliais da Veia Umbilical Humana/metabolismo , Humanos , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais , Fator A de Crescimento do Endotélio Vascular/genética
17.
Food Res Int ; 156: 111024, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35650990

RESUMO

In this study, a twelve-week intervention was conducted to investigate the anti-obesity effects of yak bone collagen hydrolysates (YBCH) on mice with a high-fat diet. The obesity-associated phenotypes of mice were detected and the feces of mice were jointly analyzed by 16S rRNA gene sequencing and untargeted metabolomics. Results indicated that supplementation with YBCH could ameliorate the obesity-associated phenotypes of mice, especially with the medium dose (MD) and high dose (HD) of YBCH. Compared with the high-fat diet control (HC) group, the ratio of Firmicutes and Bacteroidetes in the fecal microbiota of the low dose (LD), MD, and HD groups was separately decreased by 29.83 %, 70.85 %, and 75.70 %. Lachnospiraceae and Muribaculaceae were the key bacteria for the YBCH intervention, which might be attributed to their different substrate preferences. The joint analysis of the 16S rRNA gene sequencing and untargeted metabolomics suggested that the anti-obesity effects of YBCH might be achieved by up-regulating the arginine and proline metabolism and down-regulating the aromatic amino acids metabolism via the gut microbiota.


Assuntos
Dieta Hiperlipídica , Microbioma Gastrointestinal , Animais , Bacteroidetes/genética , Bovinos , Colágeno , Dieta Hiperlipídica/efeitos adversos , Fezes , Metabolômica , Camundongos , Camundongos Endogâmicos C57BL , Obesidade/metabolismo , RNA Ribossômico 16S/genética
18.
J Cancer ; 13(3): 890-905, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35154457

RESUMO

Purpose Gastric cancer (GC) is associated with rapid disease progression and poor patient prognosis, highlighting the pressing need for new biomarkers to facilitate disease management. Exosomes are released by all cells and are ubiquitous in body fluids, thus giving them great potential as diagnostic biomarkers and therapeutic targets. MicroRNAs (miRNAs) can be transported by exosomes, and are a common target for regulation in cancer. Methods Our screen of miRNAs in the Gene Expression Omnibus and The Cancer Genome Atlas databases identified miR-552-5p as the most overexpressed miRNA in GC, and we investigated its function and mechanism of action. Results We detected high expression of miR-552-5p in GC tissues, plasma samples and cell lines. We found that miR-552-5p binds directly to the 3'-untranslated region of PTEN, and the resulting downregulation of PTEN in turn downregulates the tumor suppressor TOB1. Furthermore, experiments in cell culture and mice showed that miR-552-5p in exosomes is internalized by recipient cells, where it enhances proliferation, migration and the epithelial-mesenchymal transition, while suppressing the caspase-3 apoptotic pathway. These effects were reversed by inhibiting miR-552-5p. Conclusion GC-derived exosomal miR-552-5p facilitates tumorigenesis by interfering with the PTEN/TOB1 axis, providing new potential therapeutic targets.

19.
Theranostics ; 12(1): 59-75, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34987634

RESUMO

The outcome of sonodynamic immunotherapy is significantly limited by tumor hypoxia. To overcome this obstacle, one common solution is to catalyze the conversion of endogenous H2O2 into O2. However, the effectiveness of this strategy is limited by the insufficient concentration of H2O2 in the tumor microenvironment (TME). Herein, we developed a H2O2 economizer for on-demand O2 supply and sonosensitizer-mediated reactive oxygen species production during ultrasound activation, thereby alleviating hypoxia-associated limitations and augmenting the efficacy of sonodynamic immunotherapy. Methods: The H2O2 economizer is constructed by electrostatic adsorption and π-π interactions between the Fe-doped polydiaminopyridine (Fe-PDAP) nanozyme and chlorin e6. By employing a biomimetic engineering strategy with cancer cell membranes, we addressed the premature leakage issue and increased tumor-site accumulation of nanoparticles (membrane-coated Fe-PDAP/Ce6, MFC). Results: The prepared MFC could significantly attenuate the catalytic activity of Fe-PDAP by reducing their contact with H2O2. Ultrasound irradiation promoted MFC dissociation and the exposure of Fe-PDAP for a more robust O2 supply. Moreover, the combination of MFC-enhanced sonodynamic therapy with anti-programmed cell death protein-1 antibody (aPD-1) immune checkpoint blockade induced a strong antitumor response against both primary tumors and distant tumors. Conclusion: This as-prepared H2O2 economizer significantly alleviates tumor hypoxia via reducing H2O2 expenditure and that on-demand oxygen-elevated sonodynamic immunotherapy can effectively combat tumors.


Assuntos
Peróxido de Hidrogênio/uso terapêutico , Imunoterapia/métodos , Neoplasias/terapia , Microambiente Tumoral , Terapia por Ultrassom/métodos , Animais , Linhagem Celular Tumoral , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Nanopartículas , Espécies Reativas de Oxigênio/metabolismo , Hipóxia Tumoral
20.
J Pharm Sci ; 111(6): 1625-1632, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-34706285

RESUMO

Spherical crystallization is a promising process intensification technique, where surfactant is an important ingredient in formulation but needs to be used carefully due to toxicological reasons. This work proposes to adopt colloidal particles stabilized Pickering emulsions for spherical crystallization, in order to eliminate or reduce the surfactant use. A representative system is selected for study, where silica nanoparticles are prepared to stabilize emulsions and evaporative crystallization of ibuprofen is carried out. Depletion attraction is exploited to improve the Pickering emulsion stability for better confining on crystallization with two depletants PEG and PVA tested. Crystal products from the emulsions prepared with silica nanoparticles and the non-ionic surfactant Tween 20 are compared. The results show that depletion attraction is helpful for producing stable Pickering emulsions with high dispersed phase fraction and mono-dispersed ibuprofen spherical agglomerates. Silica nanoparticles contribute to reduced induction time by boosting heterogeneous nucleation and mitigate secondary agglomeration possibly by steric effects.


Assuntos
Ibuprofeno , Nanopartículas , Cristalização , Emulsões/química , Nanopartículas/química , Dióxido de Silício , Tensoativos/química
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