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1.
Mol Divers ; 2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38807000

RESUMO

E76A mutations of SHP2 have been reported to associate with genetic developmental diseases and cancers, and TNO155 is one of the effective inhibitors targeted to the allosteric site 1, which has already entered the clinical stage. However, the detailed binding mechanism between them still needs further clarification at micro-atomic level. In this study, the binding mechanism of TNO155 inhibiting SHP2E76A and the superiorities of TNO155 at binding affinity and dynamic interactive behavior with SHP2E76A were probed utilizing a series of computational drug design technologies. The results show that SHP2E76A forms tighter interaction with TNO155 compared to SHP099. SHP2E76A-TNO155 exhibits the largest electrostatic interaction among all complex systems, which can be manifested by the strong hydrogen bond interactions formed by two electrically charged residues, Arg111 and Glu250. Notably, in SHP2E76A-TNO155 system, Asp489 makes an additional substantial beneficial contribution. The E76A mutation brings stronger residue positive correlation and a larger conformation fluctuation between N-CH2 and PTP domains, resulting in tighter binding between TNO155 and SHP2E76A. This study offers valuable insights for the further design and development of novel SHP2E76A allosteric inhibitors.

2.
Anal Chem ; 96(21): 8782-8790, 2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38728110

RESUMO

Sensitive and on-site discrimination of live and dead foodborne pathogenic strains remains a significant challenge due to the lack of appropriate assay and signal probes. In this work, a versatile platinum nanoparticle-decorated phage nanozyme (P2@PtNPs) that integrated recognition, bacteriolysis, and catalysis was designed to establish the bioluminescence/pressure dual-mode bioassay for on-site determination of the vitality of foodborne pathogenic strains. Benefiting from the bacterial strain-level specificity of phage, the target Salmonella typhimurium (S.T) was specially captured to form sandwich complexes with P2@PtNPs on another phage-modified glass microbead (GM@P1). As the other part of the P2@PtNPs nanozyme, the introduced PtNPs could not only catalyze the decomposition of hydrogen peroxide to generate a significant oxygen pressure signal but also produce hydroxyl radicals around the target bacteria to enhance the bacteriolysis of phage and adenosine triphosphate release. It significantly improved the bioluminescence signal. The two signals corresponded to the total and live target bacteria counts, so the dead target could be easily calculated from the difference between the total and live target bacteria counts. Meanwhile, the vitality of S.T was realized according to the ratio of live and total S.T. Under optimal conditions, the application range of this proposed bioassay for bacterial vitality was 102-107 CFU/mL, with a limit of detections for total and live S.T of 30 CFU/mL and 40 CFU/mL, respectively. This work provides an innovative and versatile nanozyme signal probe for the on-site determination of bacterial vitality for food safety.


Assuntos
Bacteriófagos , Medições Luminescentes , Nanopartículas Metálicas , Platina , Salmonella typhimurium , Platina/química , Nanopartículas Metálicas/química , Salmonella typhimurium/isolamento & purificação , Salmonella typhimurium/virologia , Salmonella typhimurium/química , Catálise , Bacteriófagos/química , Microbiologia de Alimentos , Bioensaio/métodos , Técnicas Biossensoriais/métodos , Pressão , Peróxido de Hidrogênio/química
3.
World J Surg Oncol ; 22(1): 55, 2024 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-38365759

RESUMO

BACKGROUND: Cervical cancer (CC) is a common malignancy of the female reproductive tract, and preoperative prediction of lymph node metastasis (LNM) is essential. This study aims to design and validate a magnetic resonance imaging (MRI) radiomics-based predictive model capable of detecting LNM in patients diagnosed with CC. METHODS: This retrospective analysis incorporated 86 and 38 CC patients into the training and testing groups, respectively. Radiomics features were extracted from MRI T2WI, T2WI-SPAIR, and axial apparent diffusion coefficient (ADC) sequences. Selected features identified in the training group were then used to construct a radiomics scoring model, with relevant LNM-related risk factors having been identified through univariate and multivariate logistic regression analyses. The resultant predictive model was then validated in the testing cohort. RESULTS: In total, 16 features were selected for the construction of a radiomics scoring model. LNM-related risk factors included worse differentiation (P < 0.001), more advanced International Federation of Gynecology and Obstetrics (FIGO) stages (P = 0.03), and a higher radiomics score from the combined MRI sequences (P = 0.01). The equation for the predictive model was as follows: -0.0493-2.1410 × differentiation level + 7.7203 × radiomics score of combined sequences + 1.6752 × FIGO stage. The respective area under the curve (AUC) values for the T2WI radiomics score, T2WI-SPAIR radiomics score, ADC radiomics score, combined sequence radiomics score, and predictive model were 0.656, 0.664, 0.658, 0.835, and 0.923 in the training cohort, while these corresponding AUC values were 0.643, 0.525, 0.513, 0.826, and 0.82 in the testing cohort. CONCLUSIONS: This MRI radiomics-based model exhibited favorable accuracy when used to predict LNM in patients with CC. Relative to the use of any individual MRI sequence-based radiomics score, this predictive model yielded superior diagnostic accuracy.


Assuntos
Neoplasias do Colo do Útero , Humanos , Feminino , Metástase Linfática/patologia , Estudos Retrospectivos , Neoplasias do Colo do Útero/patologia , Radiômica , Imageamento por Ressonância Magnética/métodos , Linfonodos/diagnóstico por imagem , Linfonodos/cirurgia , Linfonodos/patologia
4.
Cell Death Dis ; 15(2): 163, 2024 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-38388468

RESUMO

In clinical practice, renal ischemia-reperfusion injury (IRI) is a common cause of acute kidney injury (AKI), often leading to acute renal failure or end-stage renal disease (ESRD). The current understanding of renal IRI mechanisms remains unclear, and effective therapeutic strategies and clear targets are lacking. Therefore, the need to find explicit and effective ways to reduce renal IRI remains a scientific challenge. The current study explored pyroptosis, a type of inflammation-regulated programmed cell death, and the role of Gasdermins E (GSDME)-mediated pyroptosis, mitochondrial damage, and inflammation in renal IRI. The analysis of human samples showed that the expression levels of GSDME in normal human renal tissues were higher than those of GSDMD. Moreover, our study demonstrated that GSDME played an important role in mediating pyroptosis, inflammation, and mitochondrial damage in renal IRI. Subsequently, GSDME-N accumulated in the mitochondrial membrane, leading to mitochondrial damage and activation of caspase3, which generated a feed-forward loop of self-amplification injury. However, GSDME knockout resulted in the amelioration of renal IRI. Moreover, the current study found that the transcription factor CHOP was activated much earlier in renal IRI. Inhibition of BCL-2 by CHOP leaded to casapse3 activation, resulting in mitochondrial damage and apoptosis; not only that, but CHOP positively regulated GSDME thereby causing pyroptosis. Therefore, this study explored the transcriptional mechanisms of GSDME during IRI development and the important role of CHOP/Caspase3/GSDME mechanistic axis in regulating pyroptosis in renal IRI. This axis might serve as a potential therapeutic target.


Assuntos
Injúria Renal Aguda , Traumatismo por Reperfusão , Humanos , Piroptose/genética , Gasderminas , Rim/metabolismo , Inflamação/genética , Injúria Renal Aguda/genética , Traumatismo por Reperfusão/genética , Traumatismo por Reperfusão/metabolismo
5.
Altern Ther Health Med ; 30(1): 441-445, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37820680

RESUMO

Objective: To compare the difference in the effectiveness of ranibizumab (LU) and aflibercept (AF) in the treatment of diabetic retinopathy (DR). Methods: Ninety-four patients with DR admitted to Sunshine Union Hospital from August 2020 to February 2022 were selected for the study and were divided into LU group (n = 47) and AF group (n = 47) according to the random number table method. Both groups underwent 25G vitrectomy in our hospital, with LU injected into the vitreous before surgery in the LU group and AF in the AF group. Vascular endothelial growth factor (VEGF) and pigment epithelium-derived factor (PEDF) in the pre-and post-injection atrial water were compared between the two groups, and the operative time, intraoperative bleeding, and the occurrence of medically induced fissures were recorded in both groups. In addition, the expression of best corrected visual acuity (BCVA), Central Macular Thickness (CMT), and inflammatory factors were compared before and after surgery. Finally, patients were counted for adverse reactions and prognosis of DR recurrence during treatment. Results: After injection, VEGF decreased and PEDF increased in both groups (P < .001). There were no differences in operative time (P = .604), intraoperative bleeding rate (P = .694), the incidence of medically induced fissure (P = .557), BCVA [P = .665 (T0), P > .999 (T1), P = .727 (T2)], and CMT [P = .688 (T0), P = .065 (T1), P = .148 (T2)] between the two groups, while IL-6, IL-8, and MMP-9 were lower in the AF group than in the LU group at 2 months after surgery (P < .001). Finally, there was no difference between both groups in terms of adverse effects and prognosis of DR recurrence rate (P = 1.000, .478). Conclusion: Both vitreous cavity injections of LU and AF can effectively reduce the expression of vascular-related factors in the atrial fluid of DR patients, but AF has a more significant inhibitory effect on the level of inflammatory factors in patients in the short term after treatment.


Assuntos
Diabetes Mellitus , Retinopatia Diabética , Receptores de Fatores de Crescimento do Endotélio Vascular , Proteínas Recombinantes de Fusão , Humanos , Ranibizumab/uso terapêutico , Retinopatia Diabética/tratamento farmacológico , Retinopatia Diabética/induzido quimicamente , Fator A de Crescimento do Endotélio Vascular/uso terapêutico , Inibidores da Angiogênese/uso terapêutico , Resultado do Tratamento
6.
Clin Transl Med ; 13(8): e1359, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37537731

RESUMO

BACKGROUND: N6 -methyladenosine (m6A) is of great importance in renal physiology and disease progression, but its function and mechanism in renal fibrosis remain to be comprehensively and extensively explored. Hence, this study will explore the function and potential mechanism of critical regulator-mediated m6A modification during renal fibrosis and thereby explore promising anti-renal fibrosis agents. METHODS: Renal tissues from humans and mice as well as HK-2 cells were used as research subjects. The profiles of m6A modification and regulators in renal fibrosis were analysed at the protein and RNA levels using Western blotting, quantitative real-time polymerase chain reaction and other methods. Methylation RNA immunoprecipitation sequencing and RNA sequencing coupled with methyltransferase-like 3 (METTL3) conditional knockout were used to explore the function of METTL3 and potential targets. Gene silencing and overexpression combined with RNA immunoprecipitation were performed to investigate the underlying mechanism by which METTL3 regulates the Ena/VASP-like (EVL) m6A modification that promotes renal fibrosis. Molecular docking and virtual screening with in vitro and in vivo experiments were applied to screen promising traditional Chinese medicine (TCM) monomers and explore their mechanism of regulating the METTL3/EVL m6A axis and anti-renal fibrosis. RESULTS: METTL3 and m6A modifications were hyperactivated in both the tubular region of fibrotic kidneys and HK-2 cells. Upregulated METTL3 enhanced the m6A modification of EVL mRNA to improve its stability and expression in an insulin-like growth factor 2 mRNA-binding protein 2 (IGF2BP2)-dependent manner. Highly expressed EVL binding to Smad7 abrogated the Smad7-induced suppression of transforming growth factor-ß (TGF-ß1)/Smad3 signal transduction, which conversely facilitated renal fibrosis progression. Molecular docking and virtual screening based on the structure of METTL3 identified a TCM monomer named isoforsythiaside, which inhibited METTL3 activity together with the METTL3/EVL m6A axis to exert anti-renal fibrosis effects. CONCLUSIONS: Collectively, the overactivated METTL3/EVL m6A axis is a potential target for renal fibrosis therapy, and the pharmacological inhibition of METTL3 activity by isoforsythiaside suggests that it is a promising anti-renal fibrosis agent.


Assuntos
Metiltransferases , RNA , Animais , Humanos , Camundongos , Fibrose , Metiltransferases/genética , Metiltransferases/metabolismo , Simulação de Acoplamento Molecular , RNA Mensageiro/genética , Proteínas de Ligação a RNA
7.
Br J Pharmacol ; 180(1): 5-24, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36196023

RESUMO

Epigenetic modifications have received increasing attention and have been shown to be extensively involved in kidney development and disease progression. Among them, the most common RNA modification, N6 -methyladenosine (m6 A), has been shown to dynamically and reversibly exert its functions in multiple ways, including splicing, export, decay and translation initiation efficiency to regulate mRNA fate. Moreover, m6 A has also been reported to exert biological effects by destabilizing base pairing to modulate various functions of RNAs. Most importantly, an increasing number of kidney diseases, such as renal cell carcinoma, acute kidney injury and chronic kidney disease, have been found to be associated with aberrant m6 A patterns. In this review, we comprehensively review the critical roles of m6 A in kidney diseases and discuss the possibilities and relevance of m6 A-targeted epigenetic therapy, with an integrated comprehensive description of the detailed alterations in specific loci that contribute to cellular processes that are associated with kidney diseases.


Assuntos
Injúria Renal Aguda , Carcinoma de Células Renais , Neoplasias Renais , Humanos , RNA , RNA Mensageiro
8.
Bioorg Med Chem ; 67: 116838, 2022 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-35617790

RESUMO

Honokiol, isolated from a traditional Chinese medicine (TCM) Magnolia officinalis, is a biphenolic compound with several biological activities. To improve and broaden its biological activity, herein, two series of honokiol thioethers bearing 1,3,4-oxadiazole moieties were prepared and assessed for their α-glucosidase and SARS-CoV-2 entry inhibitory activities. Among all the honokiol thioethers, compound 7l exhibited the strongest α-glucosidase inhibitory effect with an IC50 value of 18.9 ± 2.3 µM, which was superior to the reference drug acarbose (IC50 = 24.4 ± 0.3 µM). Some interesting results of structure-activity relationships (SARs) have also been discussed. Enzyme kinetic study demonstrated that 7l was a noncompetitive α-glucosidase inhibitor, which was further supported by the results of molecular docking. Moreover, honokiol thioethers 7e, 9a, 9e, and 9r exhibited potent antiviral activity against SARS-CoV-2 pseudovirus entering into HEK-293 T-ACE2h. Especially 9a displayed the strongest inhibitory activity against SARS-CoV-2 pseudovirus entry with an IC50 value of 16.96 ± 2.45 µM, which was lower than the positive control Evans blue (21.98 ± 1.98 µM). Biolayer interferometry (BLI) binding and docking studies suggested that 9a and 9r may effectively block the binding of SARS-CoV-2 to the host ACE2 receptor through dual recognition of SARS-CoV-2 spike RBD and human ACE2. Additionally, the potent honokiol thioethers 7l, 9a, and 9r displayed relatively no cytotoxicity to normal cells (LO2). These findings will provide a theoretical basis for the discovery of honokiol derivatives as potential both α-glucosidase and SARS-CoV-2 entry inhibitors.


Assuntos
Tratamento Farmacológico da COVID-19 , SARS-CoV-2 , Enzima de Conversão de Angiotensina 2 , Compostos de Bifenilo , Células HEK293 , Humanos , Lignanas , Simulação de Acoplamento Molecular , Oxidiazóis , Ligação Proteica , Glicoproteína da Espícula de Coronavírus/química , Sulfetos , alfa-Glucosidases/metabolismo
9.
J Healthc Eng ; 2022: 1499927, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35432822

RESUMO

To evaluate the application effect of the 360° safe indwelling infusion program of peripheral venous indwelling needle in the infusion room of pediatric outpatient clinic. A total of 1,000 children who received indwelling needle infusion were randomly divided into experimental group (n = 500; 360° safe indwelling needle) and control group (n = 500; a routine indwelling needle). The incidence of indwelling needle-related complications and adverse events in the experimental group was significantly lower than that in the control group, and the number of indwelling days, indwelling needle usage rate, and parent satisfaction were significantly higher than those in the control group. The 360° safe indwelling infusion program can significantly reduce the incidence of complications and adverse events, and improve the quality of the indwelling needle infusion. The 360° safe indwelling infusion can effectively improve the comprehensive quality and safety of nursing care in the outpatient infusion room.


Assuntos
Instituições de Assistência Ambulatorial , Agulhas , Criança , Humanos
10.
Stroke ; 53(1): 167-176, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34601899

RESUMO

BACKGROUND AND PURPOSE: Hematoma volume (HV) is a significant diagnosis for determining the clinical stage and therapeutic approach for intracerebral hemorrhage (ICH). The aim of this study is to develop a robust deep learning segmentation method for the fast and accurate HV analysis using computed tomography. METHODS: A novel dimension reduction UNet (DR-UNet) model was developed for computed tomography image segmentation and HV measurement. Two data sets, 512 ICH patients with 12 568 computed tomography slices in the retrospective data set and 50 ICH patients with 1257 slices in the prospective data set, were used for network training, validation, and internal and external testing. Moreover, 13 irregular hematoma cases, 11 subdural and epidural hematoma cases, and 50 different HV cases into 3 groups (<30, 30-60, and >60 mL) were selected to further evaluate the robustness of DR-UNet. The image segmentation performance of DR-UNet was compared with those of UNet, the fuzzy clustering method, and the active contour method. The HV measurement performance was compared using DR-UNet, UNet, and the Coniglobus formula method. RESULTS: Using DR-UNet, the segmentation model achieved a performance similar to that of expert clinicians in 2 independent test data sets containing internal testing data (Dice of 0.861±0.139) and external testing data (Dice of 0.874±0.130). The HV measurement derived from DR-UNet was strongly correlated with that from manual segmentation (R2=0.9979; P<0.0001). In the irregularly shaped hematoma group and the subdural and epidural hematoma group, DR-UNet was more robust than UNet in both hematoma segmentation and HV measurement. There is no statistical significance in segmentation accuracy among 3 different HV groups. CONCLUSIONS: DR-UNet can segment hematomas from the computed tomography scans of ICH patients and quantify the HV with better accuracy and greater efficiency than the main existing methods and with similar performance to expert clinicians. Due to robust performance and stable segmentation on different ICHs, DR-UNet could facilitate the development of deep learning systems for a variety of clinical applications.


Assuntos
Hemorragia Cerebral/diagnóstico por imagem , Aprendizado Profundo , Hematoma/diagnóstico por imagem , Processamento de Imagem Assistida por Computador/métodos , Tomografia Computadorizada por Raios X/métodos , Adulto , Idoso , Bases de Dados Factuais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Estudos Retrospectivos
11.
Int J Pharm ; 612: 121366, 2022 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-34896216

RESUMO

Ionic liquids (ILs) usually refer to kinds of salts with melting point below 100 °C and are composed of definite anions and cations. In recent years, in addition to the field of material engineering, the applications of ILs have been extended to biomedical application. As a solubilizer, skin penetration enhancer, antibacterial agent, and macromolecular stabilizer of poorly soluble active pharmaceutical ingredients, ILs have attracted great attention in the field of pharmaceutical research. Among them, choline-based ILs are very popular in the field of drug delivery due to their biocompatibility, biodegradability, low toxicity or non-toxicity and other characteristics. This article mainly reviews the applications of choline-based ILs formed by choline and organic acid and choline-based ionic liquids-pharmaceutical active ingredients in transdermal delivery, topical delivery and oral delivery.


Assuntos
Líquidos Iônicos , Preparações Farmacêuticas , Administração Cutânea , Colina , Sistemas de Liberação de Medicamentos
12.
J Agric Food Chem ; 69(51): 15544-15553, 2021 Dec 29.
Artigo em Inglês | MEDLINE | ID: mdl-34919380

RESUMO

To improve the insecticidal activity of (+)-nootkatone, a series of 42 (+)-nootkatone thioethers containing 1,3,4-oxadiazole/thiadiazole moieties were prepared to evaluate their insecticidal activities against Mythimna separata Walker, Myzus persicae Sulzer, and Plutella xylostella Linnaeus. Insecticidal evaluation revealed that most of the title derivatives exhibited more potent insecticidal activities than the precursor (+)-nootkatone after the introduction of 1,3,4-oxadiazole/thiadiazole on (+)-nootkatone. Among all of the (+)-nootkatone derivatives, compound 8c (1 mg/mL) exhibited the best growth inhibitory (GI) activity against M. separata with a final corrected mortality rate (CMR) of 71.4%, which was 1.54- and 1.43-fold that of (+)-nootkatone and toosendanin, respectively; 8c also displayed the most potent aphicidal activity against M. persicae with an LD50 value of 0.030 µg/larvae, which was closer to that of the commercial insecticidal etoxazole (0.026 µg/larvae); and 8s showed the best larvicidal activity against P. xylostella with an LC50 value of 0.27 mg/mL, which was 3.37-fold that of toosendanin and slightly higher than that of etoxazole (0.28 mg/mL). Furthermore, the control efficacy of 8s against P. xylostella in the pot experiments under greenhouse conditions was better than that of etoxazole. Structure-activity relationships (SARs) revealed that in most cases, the introduction of 1,3,4-oxadiazole/thiadiazole containing halophenyl groups at the C-13 position of (+)-nootkatone could obtain more active derivatives against M. separata, M. persicae, and P. xylostella than those containing other groups. In addition, toxicity assays indicated that these (+)-nootkatone derivatives had good selectivity to insects over nontarget organisms (normal mammalian NRK-52E cells and C. idella and N. denticulata fries) with relatively low toxicity. Therefore, the above results indicate that these (+)-nootkatone derivatives could be further explored as new lead compounds for the development of potential eco-friendly pesticides.


Assuntos
Inseticidas , Mariposas , Tiadiazóis , Animais , Inseticidas/farmacologia , Larva , Estrutura Molecular , Oxidiazóis , Sesquiterpenos Policíclicos , Relação Estrutura-Atividade , Sulfetos , Tiadiazóis/farmacologia
13.
Bioorg Chem ; 104: 104294, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32987307

RESUMO

Nowadays, the discovery and development of α-glucosidase inhibitors from natural products or their derivatives represents an attractive approach. Here we reported studies on a series of novel N-acyl-2-aminothiazoles fused (+)-nootkatone and evaluation for their α-glucosidase inhibitory activities. Most of (+)-nootkatone derivatives exhibited more potent α-glucosidase inhibitory ability than the positive drug acarbose. In particular, compounds II7 and II14 showed the most promising α-glucosidase inhibitory ability with IC50 values of 13.2 and 13.8 µM. II7 and II14 also exhibited relatively low cytotoxicities towards normal LO2 cells. Kinetic study indicated that compounds II7 and II14 inhibited the α-glucosidase in a noncompetitive manner, and molecular docking results were in line with the noncompetitive characteristics that II7 and II14 did not bind to the known active sites (Asp214, Glu276 and Asp349). Based on our findings, these (+)-nootkatone derivatives could be used as antidiabetic candidates.


Assuntos
Citrus paradisi/química , Descoberta de Drogas , Inibidores de Glicosídeo Hidrolases/farmacologia , Simulação de Acoplamento Molecular , Sesquiterpenos Policíclicos/farmacologia , Tiazóis/farmacologia , Relação Dose-Resposta a Droga , Inibidores de Glicosídeo Hidrolases/química , Inibidores de Glicosídeo Hidrolases/isolamento & purificação , Estrutura Molecular , Sesquiterpenos Policíclicos/química , Sesquiterpenos Policíclicos/isolamento & purificação , Saccharomyces cerevisiae/enzimologia , Relação Estrutura-Atividade , Tiazóis/química , Tiazóis/isolamento & purificação , alfa-Glucosidases/metabolismo
14.
Inorg Chem ; 59(14): 9919-9926, 2020 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-32643931

RESUMO

As efficient and stable nuclear waste forms, single-phase uranium (U6+)-incorporated La2Zr2O7 nanoparticles were designed and synthesized in an air atmosphere. To obtain a high U loading, divalent magnesium (Mg2+) was introduced to balance the extra charge from the substitution of tetravalent zirconium (Zr4+) by U6+ with a minimized impact to the lattice. There is a composition-driven phase transition from order pyrochlore to defect fluorite as the U concentration increases from 10 to 30 mol %, demonstrating both good solubility and stability of the La2Zr2O7 host for U and potentially for other actinides. La2(UxMgxZr1-2x)2O7 (x = 0-0.3) nanoparticles showed good dispersity and crystallinity with an average particle size of ∼48 nm. Furthermore, X-ray photoelectron spectroscopy, Raman spectroscopy, and emission spectroscopy revealed that U was stabilized in the hexavalent state in the form of a UO22+ ion. Spectroscopic methods also demonstrated that our samples caused a scintillating response with an orange emission (597 nm) by 230 nm excitation. In addition, density functional theory simulations were employed to investigate the atomic structures and electronic properties of the U-incorporated pyrochlores. The calculated bond lengths, atomic charges, and charge density confirm the existence of UO22+ ions. Supported by both experimental and computational results, a novel geometrical structure was proposed to explain the Mg2+-U6+ substitution. This work demonstrated the successful development of U-incorporated La2Zr2O7 nanoparticles and provided an efficient way to immobilize U in these ceramic waste matrixes.

15.
Bioorg Med Chem Lett ; 30(15): 127260, 2020 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-32527454

RESUMO

Natural products are very important sources for the development of new pesticides. Osthole, derived from many medical plants such as Cnidium, Angelica and Citrus plants, is a naturally occurring coumarin compound. To discover the new natural products-based insecticides, thirty-one osthole-based esters containing O-acyl-hydroxylamine groups were prepared, and their structures were identified by different spectral analysis methods. Derivatives A7, A17, A20 and A25 displayed more potent growth inhibitory (GI) activity than the botanical insecticide, toosendanin. Over half of target osthole derivatives had more effective larvicidal effect on P. xylostella than toosendanin. Among all title derivatives, compound A18 displayed more pronounced larvicidal activity (LC50 = 0.64 µmol mL-1) when compared with toosendanin (LC50 = 0.94 µmol mL-1). Some interesting results of structure-activity relationships (SARs) of these osthole derivatives were also discussed. In addition, the hemolysis and cytotoxicity assays indicated that these osthole derivatives showed very low toxicity toward normal mammalian cells.


Assuntos
Produtos Biológicos/farmacologia , Cumarínicos/farmacologia , Inseticidas/farmacologia , Lepidópteros/efeitos dos fármacos , Angelica/química , Animais , Produtos Biológicos/química , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Citrus/química , Cnidium/química , Cumarínicos/química , Relação Dose-Resposta a Droga , Inseticidas/química , Estrutura Molecular , Ratos , Relação Estrutura-Atividade
16.
J Am Chem Soc ; 140(21): 6596-6603, 2018 05 30.
Artigo em Inglês | MEDLINE | ID: mdl-29668265

RESUMO

CRISPR-Cas RNA-guided endonucleases hold great promise for disrupting or correcting genomic sequences through site-specific DNA cleavage and repair. However, the lack of methods for cell- and tissue-selective delivery currently limits both research and clinical uses of these enzymes. We report the design and in vitro evaluation of S. pyogenes Cas9 proteins harboring asialoglycoprotein receptor ligands (ASGPrL). In particular, we demonstrate that the resulting ribonucleoproteins (Cas9-ASGPrL RNP) can be engineered to be preferentially internalized into cells expressing the corresponding receptor on their surface. Uptake of such fluorescently labeled proteins in liver-derived cell lines HEPG2 (ASGPr+) and SKHEP (control; diminished ASGPr) was studied by live cell imaging and demonstrates increased accumulation of Cas9-ASGPrL RNP in HEPG2 cells as a result of effective ASGPr-mediated endocytosis. When uptake occurred in the presence of a peptide with endosomolytic properties, we observed receptor-facilitated and cell-type specific gene editing that did not rely on electroporation or the use of transfection reagents. Overall, these in vitro results validate the receptor-mediated delivery of genome-editing enzymes as an approach for cell-selective gene editing and provide a framework for future potential applications to hepatoselective gene editing in vivo.


Assuntos
Sistemas CRISPR-Cas , Endonucleases/metabolismo , Edição de Genes , Linhagem Celular Tumoral , Endonucleases/genética , Células Hep G2 , Humanos , Estrutura Molecular , Engenharia de Proteínas
17.
Asian Pac J Cancer Prev ; 15(21): 9319-25, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25422219

RESUMO

Alkaloids are the most extensively featured compounds of natural anti-tumor herbs, which have attracted much attention in pharmaceutical research. In our previous studies, a mixture of major three alkaloid components (5, 6-dihydrobicolorine, 7-deoxy-trans-dihydronarciclasine, littoraline) from Hymenocallis littoralis were extracted, analyzed and designated as AHL. In this paper, AHL extracts were added to human liver hepatocellular cells HepG-2, human gastric cancer cell SGC-7901, human breast adenocarcinoma cell MCF-7 and human umbilical vein endothelial cell EVC-304, to screen one or more AHL-sensitive tumor cell. Among these cells, HepG-2 was the most sensitive to AHL treatment, a very low dose (0.8µg/ml) significantly inhibiting proliferation . The non- tumor cell EVC-304, however, was not apparently affected. Effect of AHL on HepG-2 cells was then explored. We found that the AHL could cause HepG-2 cycle arrest at G2/M checkpoint, induce apoptosis, and interrupt polymerization of microtubules. In addition, expression of two cell cycle-regulated proteins, CyclinB1 and CDK1, was up-regulated upon AHL treatment. Up-regulation of the Fas, Fas ligand, Caspase-8 and Caspase-3 was observed as well, which might imply roles for the Fas/FsaL signaling pathway in the AHL-induced apoptosis of HepG-2 cells.


Assuntos
Alcaloides/farmacologia , Apoptose/efeitos dos fármacos , Proteína Ligante Fas/efeitos dos fármacos , Liliaceae , Transdução de Sinais/efeitos dos fármacos , Apoptose/genética , Western Blotting , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular , Proteína Ligante Fas/genética , Citometria de Fluxo , Imunofluorescência , Células Hep G2/citologia , Células Hep G2/efeitos dos fármacos , Humanos , Extratos Vegetais , Valores de Referência , Sensibilidade e Especificidade , Transdução de Sinais/genética , Células Tumorais Cultivadas
18.
Respiration ; 84(5): 360-8, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22116521

RESUMO

BACKGROUND: In China, both the levels and patterns of outdoor air pollution have altered dramatically with the rapid economic development and urbanization over the past two decades. However, few studies have investigated the association of outdoor air pollution with respiratory mortality, especially in the high pollution range. OBJECTIVE: We conducted a retrospective cohort study of 9,941 residents aged ≥35 years old in Shenyang, China, to examine the association between outdoor air pollutants [particulate matter <10 µm in aerodynamic diameter (PM(10)), sulfur dioxide (SO(2)) and nitrogen dioxide (NO(2))] and mortality using 12 years of data. METHODS: We applied extended Cox proportional hazards modeling with time-dependent covariates to respiratory mortality. Analyses were also stratified by age, sex, educational level, smoking status, personal income, occupational exposure and body mass index (BMI) to examine the association of air pollution with mortality. RESULTS: We found significant associations between PM(10) and NO(2) levels and respiratory disease mortality. Our analysis found a relative risk of 1.67 [95% confidence interval (CI) 1.60-1.74] and 2.97 (95% CI 2.69-3.27) for respiratory mortality per 10 µg/m(3) increase in PM(10) and NO(2), respectively. The effects of air pollution were more apparent in women than in men. Age, sex, educational level, smoking status, personal income, occupational exposure, BMI and exercise frequency influenced the relationship between outdoor PM(10) and NO(2) and mortality. For SO(2), only smoking, little regular exercise and BMI above 18.5 influenced the relationship with mortality. CONCLUSION: These data contribute to the scientific literature on the long-term effects of air pollution for the high-exposure settings typical in developing countries.


Assuntos
Poluição do Ar/estatística & dados numéricos , Exposição Ambiental/efeitos adversos , Pneumopatias/mortalidade , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Poluição do Ar/análise , China/epidemiologia , Estudos de Coortes , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Dióxido de Nitrogênio/análise , Material Particulado/análise , Modelos de Riscos Proporcionais , Estudos Retrospectivos , Fatores Sexuais , Fumar/mortalidade , Fatores Socioeconômicos , Dióxido de Enxofre/análise
19.
Cancer Invest ; 29(7): 485-93, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21740086

RESUMO

Tumor necrosis factor (TNF)-α has been proved as an adjuvant therapy for tumor by FDA. However, the effect of chronic TNF-α expression for tumor is still controversial. In this study, we investigated the effect of low-dose TNF-α on tumor growth. We confirmed that low-dose TNF-α promoted angiogenesis of tumor in vivo, vascular endothelial growth factor (VEGF) and hypoxia-inducible factor (HIF)-1α, the transcription factor of VEGF, were both upregulated. Our results suggested that low-dose TNF-α was a powerful activator of angiogenesis in tumor and HIF-1α-VEGF pathway seemed to be the most important molecular mechanism.


Assuntos
Melanoma Experimental/patologia , Fator de Necrose Tumoral alfa/farmacologia , Fator A de Crescimento do Endotélio Vascular/biossíntese , Alantoide/irrigação sanguínea , Animais , Antígenos CD34/biossíntese , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Embrião de Galinha , Subunidade alfa do Fator 1 Induzível por Hipóxia/fisiologia , Melanoma Experimental/irrigação sanguínea , Camundongos , Camundongos Endogâmicos C57BL , Neovascularização Patológica/etiologia , Neovascularização Fisiológica
20.
PLoS One ; 6(6): e20827, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21695220

RESUMO

BACKGROUND: The relationship between ambient air pollution exposure and mortality of cardiovascular and cerebrovascular diseases in human is controversial, and there is little information about how exposures to ambient air pollution contribution to the mortality of cardiovascular and cerebrovascular diseases among Chinese. The aim of the present study was to examine whether exposure to ambient-air pollution increases the risk for cardiovascular and cerebrovascular disease. METHODOLOGY/PRINCIPAL FINDINGS: We conducted a retrospective cohort study among humans to examine the association between compound-air pollutants [particulate matter <10 µm in aerodynamic diameter (PM(10)), sulfur dioxide (SO(2)) and nitrogen dioxide (NO(2))] and mortality in Shenyang, China, using 12 years of data (1998-2009). Also, stratified analysis by sex, age, education, and income was conducted for cardiovascular and cerebrovascular mortality. The results showed that an increase of 10 µg/m(3) in a year average concentration of PM(10) corresponds to 55% increase in the risk of a death cardiovascular disease (hazard ratio [HR], 1.55; 95% confidence interval [CI], 1.51 to 1.60) and 49% increase in cerebrovascular disease (HR, 1.49; 95% CI, 1.45 to 1.53), respectively. The corresponding figures of adjusted HR (95%CI) for a 10 µg/m(3) increase in NO(2) was 2.46 (2.31 to 2.63) for cardiovascular mortality and 2.44 (2.27 to 2.62) for cerebrovascular mortality, respectively. The effects of air pollution were more evident in female that in male, and nonsmokers and residents with BMI<18.5 were more vulnerable to outdoor air pollution. CONCLUSION/SIGNIFICANCE: Long-term exposure to ambient air pollution is associated with the death of cardiovascular and cerebrovascular diseases among Chinese populations.


Assuntos
Poluição do Ar/efeitos adversos , Doenças Cardiovasculares/mortalidade , Transtornos Cerebrovasculares/mortalidade , Exposição Ambiental/efeitos adversos , Adulto , Distribuição por Idade , Idoso , Idoso de 80 Anos ou mais , Poluentes Atmosféricos/efeitos adversos , Poluentes Atmosféricos/análise , Poluição do Ar/análise , Poluição do Ar/legislação & jurisprudência , Poluição do Ar/prevenção & controle , Doenças Cardiovasculares/induzido quimicamente , Doenças Cardiovasculares/etiologia , Transtornos Cerebrovasculares/induzido quimicamente , Transtornos Cerebrovasculares/etiologia , China/epidemiologia , Escolaridade , Exposição Ambiental/legislação & jurisprudência , Exposição Ambiental/prevenção & controle , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Dióxido de Nitrogênio/efeitos adversos , Dióxido de Nitrogênio/análise , Material Particulado/efeitos adversos , Material Particulado/análise , Política Pública , Estudos Retrospectivos , Medição de Risco , Distribuição por Sexo , Classe Social , Dióxido de Enxofre/efeitos adversos , Dióxido de Enxofre/análise , Fatores de Tempo
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