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1.
Nat Commun ; 15(1): 2061, 2024 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-38448433

RESUMO

Plants are capable of altering root growth direction to curtail exposure to a saline environment (termed halotropism). The root cap that surrounds root tip meristematic stem cells plays crucial roles in perceiving and responding to environmental stimuli. However, how the root cap mediates root halotropism remains undetermined. Here, we identified a root cap-localized NAC transcription factor, SOMBRERO (SMB), that is required for root halotropism. Its effect on root halotropism is attributable to the establishment of asymmetric auxin distribution in the lateral root cap (LRC) rather than to the alteration of cellular sodium equilibrium or amyloplast statoliths. Furthermore, SMB is essential for basal expression of the auxin influx carrier gene AUX1 in LRC and for auxin redistribution in a spatiotemporally-regulated manner, thereby leading to directional bending of roots away from higher salinity. Our findings uncover an SMB-AUX1-auxin module linking the role of the root cap to the activation of root halotropism.


Assuntos
Arabidopsis , Fatores de Transcrição , Fatores de Transcrição/genética , Arabidopsis/genética , Regulação da Expressão Gênica , Estresse Salino/genética , Ácidos Indolacéticos
2.
ACS Sens ; 9(3): 1178-1187, 2024 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-38437216

RESUMO

Undoubtedly, a deep understanding of PM2.5-induced tumor metastasis at the molecular level can contribute to improving the therapeutic effects of related diseases. However, the underlying molecular mechanism of fine particle exposure through long noncoding RNA (lncRNA) regulation in autophagy and, ultimately, lung cancer (LC) metastasis remains elusive; on the other hand, the related monitoring sensor platform used to investigate autophagy and cell migration is lacking. Herein, this study performed an air-liquid interface microfluidic monitoring sensor (AIMMS) platform to analyze human bronchial epithelial cells after PM2.5 stimulation. The multiomics analysis [RNA sequencing (RNA-seq) on lncRNA and mRNA expressions separately] showed that MALAT1 was highly expressed in the PM2.5 treatment group. Furthermore, RNA-seq analysis demonstrated that autophagy-related pathways were activated. Notably, the main mRNAs associated with autophagy regulation, including ATG4D, ATG12, ATG7, and ATG3, were upregulated. Inhibition or downregulation of MALAT1 inhibited autophagy via the ATG4D/ATG12/ATG7/ATG3 pathway after PM2.5 exposure and ultimately suppressed LC metastasis. Thus, based on the AIMMS platform, we found that MALAT1 might become a promising therapeutic target. Furthermore, this low-cost AIMMS system as a fluorescence sensor integrated with the cell-monitor module could be employed to study LC migration after PM2.5 exposure. With the fluorescence cell-monitoring module, the platform could be used to observe the migration of LC cells and construct the tumor metastasis model. In the future, several fluorescence probes, including nanoprobes, could be used in the AIMMS platform to investigate many other biological processes, especially cell interaction and migration, in the fields of toxicology and pharmacology.


Assuntos
Neoplasias Pulmonares , RNA Longo não Codificante , Humanos , RNA Longo não Codificante/genética , Microfluídica , Neoplasias Pulmonares/genética , Material Particulado/toxicidade , Autofagia
3.
Langenbecks Arch Surg ; 409(1): 96, 2024 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-38483607

RESUMO

PURPOSE: The purpose of this study was to investigate the impact of autofluorescence technology on postoperative parathyroid function and short-term outcomes in patients undergoing thyroid surgery. METHODS: A total of 546 patients were included in the study, with 287 in the conventional treatment group and 259 in the autofluorescence group. Both groups underwent central lymph node dissection, which is known to affect parathyroid function. Short-term outcomes, including rates of postoperative hypocalcemia and parathyroid dysfunction, serum calcium and PTH levels on the first postoperative day, as well as the need for calcium supplementation, were analyzed. A multivariable analysis was also conducted to assess the impact of autofluorescence on postoperative parathyroid dysfunction, considering factors such as age, BMI, and preoperative calcium levels. RESULTS: The autofluorescence group demonstrated significantly lower rates of postoperative hypocalcemia and parathyroid dysfunction compared to the conventional treatment group. The autofluorescence group also had better serum calcium and PTH levels on the first postoperative day, and a reduced need for calcium supplementation. Surprisingly, the use of autofluorescence technology did not prolong surgical time; instead, it led to a shorter hospitalization duration. The multivariable analysis showed that autofluorescence significantly reduced the risk of postoperative parathyroid dysfunction, while factors such as age, BMI, and preoperative calcium levels did not show a significant correlation. CONCLUSION: This study provides evidence that autofluorescence technology can improve the preservation of parathyroid function during thyroid surgery, leading to better short-term outcomes and reduced postoperative complications. The findings highlight the potential of autofluorescence as a valuable tool in the management of parathyroid hypofunction. Further research and validation are needed to establish the routine use of autofluorescence technology in the thyroid.


Assuntos
Hipocalcemia , Hipoparatireoidismo , Neoplasias da Glândula Tireoide , Humanos , Hipocalcemia/etiologia , Hipocalcemia/prevenção & controle , Hormônio Paratireóideo , Hipoparatireoidismo/etiologia , Hipoparatireoidismo/prevenção & controle , Cálcio , Tireoidectomia/efeitos adversos , Neoplasias da Glândula Tireoide/cirurgia , Glândulas Paratireoides/cirurgia , Complicações Pós-Operatórias/etiologia
4.
Polymers (Basel) ; 16(5)2024 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-38475323

RESUMO

In order to solve the problem of excessive consumption of petrochemical resources and the harm of free formaldehyde release to human health, biomass raw materials, such as sucrose (S) and ammonium dihydrogen phosphate (ADP) can be chemically condensed in a simple route under acidic conditions to produce a formaldehyde free wood adhesive (S-ADP), characterized by good storage stability and water resistance, and higher wet shear strength with respect to petroleum based phenolic resin adhesive. The dry and boiling shear strength of the plywood based on S-ADP adhesive are as high as 1.05 MPa and 1.19 MPa, respectively. Moreover, is Modulus of Elasticity (MOE) is as high as 4910 MPa. Interestingly, the plywood based on the developed S-ADP adhesive exhibited good flame retardancy. After burning for 90 s, its shape remains unchanged. Meanwhile, it can be concluded from thermomechanical analysis (TMA) and thermogravimetric analysis (TGA) that the S-ADP acquired excellent modulus of elasticity (MOE) and good thermal stability. It is thus thought promisingly that the use of S-ADP adhesive as a substitute for PF resin adhesive seems feasible in the near future.

5.
Int J Biol Macromol ; 262(Pt 1): 130067, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38336318

RESUMO

The use of metal catalysts during the production process of cellulose acetate (CA) film can have an impact on the environment, due to their toxicity. Diphenyl phosphate (DPP) was used instead of toxic metal catalyst to react with cellulose acetate, tannin (T) and caprolactone (CL) for preparation of cellulose acetate-caprolactone-tannin (CA-CL-T) film. The results show that DPP can produce a cross-linked network structure composed of tannin, caprolactone and cellulose acetate. The maximum molecular weight reached 113,260 Da. The introduction of tannin and caprolactone into cellulose acetate caused the resulting CA-CL-T film acquire excellent strengthening/toughening effect, in which a tensile strength of 23 MPa and elongation at break of 18 % were attained. More importantly, the resistance of the film to UV radiation was significantly improved with the tannin addition, which was corroborated by the CA-CL-T film still exhibiting a tensile strength of 13 MPa and elongation at break around 13 % after continuous exposure to UV radiation for 9 days. On the other hand, the insertion of caprolactone provoked enhancement of the overall moisture resistance. Five days treatment of the films with Penicillium sp. induced gradual drop in quality, indicating the CA-CL-T film show response to biodegradation. In all, the effective crosslinking between the components of the developed material is responsible for the acquired set of these distinct characteristics.


Assuntos
Caproatos , Celulose/análogos & derivados , Lactonas , Taninos , Resistência à Tração
6.
Artigo em Inglês | MEDLINE | ID: mdl-38351686

RESUMO

BACKGROUND: Dysmenorrhea is one of the most common ailments affecting young and middle-aged women, significantly impacting their quality of life. Traditional Chinese Medicine (TCM) offers unique advantages in treating dysmenorrhea. However, an accurate diagnosis is essential to ensure correct treatment. This research integrates the age-old wisdom of TCM with modern Machine Learning (ML) techniques to enhance the precision and efficiency of dysmenorrhea syndrome differentiation, a pivotal process in TCM diagnostics and treatment planning. METHODS: A total of 853 effective cases of dysmenorrhea were retrieved from the CNKI database, including patients' syndrome types, symptoms, and features, to establish the TCM information database of dysmenorrhea. Subsequently, 42 critical features were isolated from a potential set of 86 using a selection procedure augmented by Python's Scikit-Learn Library. Various machine learning models were employed, including Logistic Regression, Random Forest Classifier, Support Vector Machine (SVM), K-Nearest Neighbors (KNN), and Artificial Neural Networks (ANN), each chosen for their potential to unearth complex patterns within the data. RESULTS: Based on accuracy, precision, recall, and F1-score metrics, SVM emerged as the most effective model, showcasing an impressive precision of 98.29% and an accuracy of 98.24%. This model's analytical prowess not only highlighted the critical features pivotal to the syndrome differentiation process but also stands to significantly aid clinicians in formulating personalized treatment strategies by pinpointing nuanced symptoms with high precision. CONCLUSION: The study paves the way for a synergistic approach in TCM diagnostics, merging ancient wisdom with computational acuity, potentially innovating the diagnosis and treatment mode of TCM. Despite the promising outcomes, further research is needed to validate these models in real-world settings and extend this approach to other diseases addressed by TCM.

7.
Bioorg Chem ; 145: 107215, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38394920

RESUMO

Doublecortin-like kinase 1 (DCLK1) is a microtubule-associated protein kinase involved in neurogenesis and human cancer. Recent studies have revealed a novel functional role for DCLK1 in inflammatory signaling, thus positioning it as a novel target kinase for respiratory inflammatory disease treatment. In this study, we designed and synthesized a series of NVP-TAE684-based derivatives as novel anti-inflammatory agents targeting DCLK1. Bio-layer interferometry binding screening and kinase assays of the NVP-TAE684 derivatives led to the discovery of an effective DCLK1 inhibitor (a24), with an IC50 of 179.7 nM. Compound a24 effectively inhibited lipopolysaccharide (LPS)-induced inflammation in macrophages with higher potency than the lead compound. Mechanistically, compound a24 inhibited LPS-induced inflammation by inhibiting DCLK1-mediated IKKß phosphorylation. Furthermore, compound a24 showed in vivo anti-inflammatory activity in an LPS-challenged acute lung injury model. These findings suggest that compound a24 may serve as a novel candidate for the development of DCLK1 inhibitors and a potential therapeutic agent for the treatment of inflammatory diseases.


Assuntos
Lesão Pulmonar Aguda , Quinases Semelhantes a Duplacortina , Humanos , Peptídeos e Proteínas de Sinalização Intracelular , Lipopolissacarídeos/farmacologia , Proteínas Serina-Treonina Quinases , Inflamação/tratamento farmacológico , Lesão Pulmonar Aguda/induzido quimicamente , Lesão Pulmonar Aguda/tratamento farmacológico
8.
Appl Biochem Biotechnol ; 196(1): 573-587, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37160564

RESUMO

Molecular-targeted therapies for lung squamous cell carcinoma (LSCC) are limited mainly because targetable oncogenic aberrations are absent in LSCC. Recent genomic analyses have revealed that the fibroblast growth factor (FGF) signaling pathway plays a fundamental role in LSCC progression via cancer cell proliferation and angiogenesis. In the present study, we designed, expressed, and purified a fibroblast growth factor receptor fragment (FGFR1-Fc) fusion protein using NS/0 cells. In FGF2-FGFR1 overexpressed NCI-H1703 cells, the FGFR1-Fc fusion protein effectively inhibited proliferation and invasion and arrested the cell cycle at the G0-G1 phase. In NCI-H1703 cells treated with the FGFR1-Fc fusion protein, the phosphorylation levels of FGFR1, FRS2, ERK, and AKT were significantly reduced. Using an siRNA assay, we demonstrated that FGF2-FGFR1 is the major anti-tumor target of FGFR1-Fc fusion the FGFR1-Fc fusion protein, which also significantly inhibited proliferation and invasion by NCI-H1703 cells via the FGF2-FGFR1 signaling pathway. In addition, the FGFR1-Fc fusion protein significantly inhibited angiogenesis in an embryonic chorioallantoic membrane model. The FGFR1-Fc fusion protein may be an effective therapeutic candidate for LSCC.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Carcinoma de Células Escamosas , Imunoglobulina G , Neoplasias Pulmonares , Proteínas Recombinantes de Fusão , Humanos , Fator 2 de Crescimento de Fibroblastos , Receptor Tipo 1 de Fator de Crescimento de Fibroblastos/genética , Receptor Tipo 1 de Fator de Crescimento de Fibroblastos/metabolismo , Proliferação de Células , Carcinoma de Células Escamosas/genética , Neoplasias Pulmonares/tratamento farmacológico , Pulmão/metabolismo , Linhagem Celular Tumoral
9.
Talanta ; 269: 125447, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38008018

RESUMO

Chlorophyll-a (Chl-a) fluorescence detection is an important technique for monitoring water quality. In this work, we proposed an approach that employs the mass-produced low-cost optical pick-up unit (OPU) extracted from the high-definition digital versatile disc (HD-DVD) drive as the key optical component for our chlorophyll-a fluorometer. The built-in blue-violet 405 nm laser diode of the OPU acts as the excitation light to perform laser-induced fluorescence (LIF). The laser driver and a series of intrinsic lenses within the OPU, such as an objective lens with a numerical aperture (NA) of 0.65 and a collimating lens, help reduce the size, cost, and system complexity of the fluorometer. By integrating off-the-shelf electronic components, miniaturized optical setups, and 3D-printed assemblies, we have developed a low-cost, easy-to-make, standalone, and portable fluorometer. Finally, we validated the performance of the device for chlorophyll-a fluorescence detection under laboratory and on-site conditions, which demonstrated its great potential in water monitoring applications. The limit of detection (LOD) for chlorophyll-a is 0.35 µg/L, the size of the device is 151 × 100 × 80 mm3, and the total cost of the proposed fluorometer is as low as 137.5 USD. © 2023 Elsevier Science. All rights reserved.

11.
Endocrine ; 2023 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-37815746

RESUMO

PURPOSE: Sex hormones are thought to be responsible for the unique gender differences in papillary thyroid cancer(PTC). Most previous studies on these have focused on the expression of estrogen receptors, or have been limited to animal studies. The aim of our study was to explore the relationship between serum sex hormones and the pathological features of PTC in the clinical setting, as further evidence of the role of sex hormones in PTC. METHODS: Retrospective data analysis of patients who underwent thyroid surgery at the Department of Thyroid Surgery, Nanjing Drum Tower Hospital from January 2022 to September 2022 Correlation between serum sex hormone and pathological features was analyzed in male patients and in menopausal female patients. Serum sex hormones include luteinizing hormone(LH), follicle stimulating hormone(FSH), estradiol(E2), total testosterone(TT), progesterone(P), and prolactin(PRL). Tumor pathological characteristics include the number and size of tumor, presence of extrathyroidal extension(ETE), presence of lymph node metastasis(LNM). RESULTS: Preoperative serum E2 in male patients was positively correlated with tumor size in PTC, LH was negatively correlated with LNM, while TT and P were negatively correlated with ETE. Similar findings were not observed in menopausal female patients. CONCLUSION: We observed that serum sex hormones correlate with the pathological features of PTC in male patients, for the first time in a clinical study. High serum estrogens may be a risk factor for PTC, while androgens are the opposite. This somewhat corroborates previous research and provides new variables for future PTC prediction models.

12.
Microsyst Nanoeng ; 9: 111, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37705925

RESUMO

Reconfigurable modular microfluidics presents an opportunity for flexibly constructing prototypes of advanced microfluidic systems. Nevertheless, the strategy of directly integrating modules cannot easily fulfill the requirements of common applications, e.g., the incorporation of materials with biochemical compatibility and optical transparency and the execution of small batch production of disposable chips for laboratory trials and initial tests. Here, we propose a manufacturing scheme inspired by the movable type printing technique to realize 3D free-assembly modular microfluidics. Double-layer 3D microfluidic structures can be produced by replicating the assembled molds. A library of modularized molds is presented for flow control, droplet generation and manipulation and cell trapping and coculture. In addition, a variety of modularized attachments, including valves, light sources and microscopic cameras, have been developed with the capability to be mounted onto chips on demand. Microfluidic systems, including those for concentration gradient generation, droplet-based microfluidics, cell trapping and drug screening, are demonstrated. This scheme enables rapid prototyping of microfluidic systems and construction of on-chip research platforms, with the intent of achieving high efficiency of proof-of-concept tests and small batch manufacturing.

13.
Nat Plants ; 9(9): 1514-1529, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37604972

RESUMO

Ammonium toxicity affecting plant metabolism and development is a worldwide problem impeding crop production. Remarkably, rice (Oryza sativa L.) favours ammonium as its major nitrogen source in paddy fields. We set up a forward-genetic screen to decipher the molecular mechanisms conferring rice ammonium tolerance and identified rohan showing root hypersensitivity to ammonium due to a missense mutation in an argininosuccinate lyase (ASL)-encoding gene. ASL localizes to plastids and its expression is induced by ammonium. ASL alleviates ammonium-inhibited root elongation by converting the excessive glutamine to arginine. Consequently, arginine leads to auxin accumulation in the root meristem, thereby stimulating root elongation under high ammonium. Furthermore, we identified natural variation in the ASL allele between japonica and indica subspecies explaining their different root sensitivity towards ammonium. Finally, we show that ASL expression positively correlates with root ammonium tolerance and that nitrogen use efficiency and yield can be improved through a gain-of-function approach.


Assuntos
Oryza , Oryza/genética , Alelos , Arginina , Nitrogênio , Plastídeos/genética
14.
Small ; 19(48): e2304032, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37528704

RESUMO

Immunogenic cell death (ICD) can activate the body's immune system via dead cell antigens to achieve immunotherapy. Currently, small molecule drugs have been used for ICD treatment in clinical, however, how to precisely control the induced ICD while treating tumors is of great significance for improving therapeutic efficacy. Based on this, a sono/light dual response strategy to tumor therapy and activation of ICD is proposed. A topological synthesis method is used to obtain sulfur-doped bismuth oxide Bi2 O3-x Sx (BS) using BiF3 (BF) as a template through reduction and a morphology-controllable bismuth-based nano-semiconductor with a narrow bandgap is constructed. Under the stimulation of ultrasound, BS can produce reactive oxygen species (ROS) through the sonocatalytic process, which cooperates with BS to consume glutathione and enhance cellular oxidative damage, further inducing ICD. Due to the introduction of sulfur in the reduction reaction, BS can achieve photothermal conversion under light, and combine with ROS to treat tumors. Further, with the assistance of ivermectin (IVM) to form composite (BSM), combined with sono/light dual strategy, ICD is promoted and DCs maturation is accelerated. The proposed ICD-mediated hyperthermia/sonocatalytic therapy strategy will pay the way for synergetic enhancement of tumor treatment efficacy and provide a feasible idea for controllable induction of ICD.


Assuntos
Hipertermia Induzida , Neoplasias , Humanos , Bismuto , Morte Celular Imunogênica , Espécies Reativas de Oxigênio , Imunoterapia , Neoplasias/terapia , Enxofre , Linhagem Celular Tumoral
15.
J Chem Inf Model ; 63(14): 4301-4311, 2023 07 24.
Artigo em Inglês | MEDLINE | ID: mdl-37399241

RESUMO

Cocrystals have significant potential in various fields such as chemistry, material, and medicine. For instance, pharmaceutical cocrystals have the ability to address issues associated with physicochemical and biopharmaceutical properties. However, it can be challenging to find proper coformers to form cocrystals with drugs of interest. Herein, a new in silico tool called 3D substructure-molecular-interaction network-based recommendation (3D-SMINBR) has been developed to address this problem. This tool first integrated 3D molecular conformations with a weighted network-based recommendation model to prioritize potential coformers for target drugs. In cross-validation, the performance of 3D-SMINBR surpassed the 2D substructure-based predictive model SMINBR in our previous study. Additionally, the generalization capability of 3D-SMINBR was confirmed by testing on unseen cocrystal data. The practicality of this tool was further demonstrated by case studies on cocrystal screening of armillarisin A (Arm) and isoimperatorin (iIM). The obtained Arm-piperazine and iIM-salicylamide cocrystals present improved solubility and dissolution rate compared to their parent drugs. Overall, 3D-SMINBR augmented by 3D molecular conformations would be a useful network-based tool for cocrystal discovery. A free web server for 3D-SMINBR can be freely accessed at http://lmmd.ecust.edu.cn/netcorecsys/.


Assuntos
Sistemas de Liberação de Medicamentos , Cristalização , Solubilidade , Conformação Molecular , Preparações Farmacêuticas
16.
Technol Health Care ; 31(6): 2319-2329, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37522234

RESUMO

BACKGROUND: Acute appendicitis in children refers to the acute inflammation of the appendix, which accounts for 20% ∼ 30% of cases of acute abdomen in pediatric surgery. OBJECTIVE: This study aimed to establish a decision tree model of complicated appendicitis in children using appendiceal ultrasound combined with an inflammatory index and evaluated its clinical efficacy in pediatric patients. METHODS: A total of 395 children admitted to the Emergency Department of the Shanghai Children's Hospital from January 2018 to December 2021 and diagnosed with appendicitis by postoperative pathology were retrospectively analyzed. According to the postoperative pathology, the children were divided into a complicated and non-complicated appendicitis group, respectively. Routine laboratory inflammatory indicators, including white blood cell count, N(%), neutrophil (Neu) count, Neu/lymphocyte ratio (NLR), C-reactive protein (CRP), and procalcitonin were collected from the two groups. Collecting data on ultrasound examination of the appendix includes whether the appendix diameter is thickened, whether the echogenicity of the mesenteric rim surrounding the appendix is enhanced, whether there is rich blood supply in the appendix, and whether there are fecaliths in the appendix lumen. The risk factors for complicated appendicitis were screened out by univariate and multivariate logistic regression analyses, the binary logistic regression prediction and decision tree models were established, respectively, and the receiver operating characteristic (ROC) curve was used to verify the accuracy of the two prediction models. RESULTS: Binary logistic regression analysis showed that CRP, NLR, the presence of an appendicolith, and peripheral retina echo enhancement were independent risk factors for complicated appendicitis in children (P< 0.05). The decision tree model had an overall accuracy of 79%, an area under the ROC curve (AUC) of 0.809 (95% confidence interval [CI] 0.780-0.865), and sensitivity and specificity of 71.3% and 77.7%, respectively. The logistic regression model had an overall accuracy of 74.9%, an AUC value of 0.823 (95% CI, 0.765-0.853), a sensitivity value of 80.3%, and a specificity of 71.8%. CONCLUSION: This predictive model, based on ultrasound of the appendix combined with inflammatory markers, provides a useful method to assist pediatric emergency physicians in diagnosing childhood appendicitis. The decision tree model reflected the interaction of various indexes, and the model was simple, intuitive, and effective.


Assuntos
Apendicite , Humanos , Criança , Apendicite/diagnóstico por imagem , Apendicite/cirurgia , Estudos Retrospectivos , China , Contagem de Leucócitos , Sensibilidade e Especificidade , Proteína C-Reativa/análise
17.
Molecules ; 28(11)2023 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-37298873

RESUMO

Regulating redox homeostasis in tumor cells and exploiting oxidative stress to damage tumors is an efficacious strategy for cancer therapy. However, the strengths of organic nanomaterials within this strategy are often ignored. In this work, a light-triggered reactive oxygen species (ROS) damaging nanoamplifier (IrP-T) was developed for enhanced photodynamic therapy (PDT). The IrP-T was fabricated with an amphiphilic iridium complex and a MTH1 inhibitor (TH287). Under green light stimulation, IrP-T catalyzed the oxygen in cells to generate ROS for realizing oxidative damage; meanwhile, TH287 increased the accumulation of 8-oxo-dGTP, further strengthening oxidative stress and inducing cell death. IrP-T could maximize the use of a small amount of oxygen, thus further boosting the efficacy of PDT in hypoxic tumors. The construction of nanocapsules provided a valuable therapeutic strategy for oxidative damage and synergizing PDT.


Assuntos
Nanocápsulas , Neoplasias , Fotoquimioterapia , Humanos , Oxigênio/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Irídio/farmacologia , Estresse Oxidativo , Neoplasias/tratamento farmacológico , Linhagem Celular Tumoral , Fármacos Fotossensibilizantes/farmacologia
18.
Langmuir ; 39(19): 6647-6656, 2023 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-37133555

RESUMO

BiVO4 has been widely used in the field of photocatalysis due to its nontoxic and moderate band gap. However, single BiVO4 has the disadvantages of a high recombination rate of photogenerated carriers and weak response to visible light, inhibiting its photocatalytic applications. To explore viable solutions, a hybrid material composed of lanthanum-doped bismuth vanadate (La-BiVO4) and oxygen-doped porous graphite carbon nitride (O-doped g-C3N4), i.e., La-BiVO4/O-doped g-C3N4 powder, was prepared by a facile hydrothermal reaction and low-temperature calcination. Then, the powder was loaded on polyacrylonitrile nanofibers (NFs) through the electrospinning fiber technique. Various surface science characterizations, including transmission electron microscopy and nitrogen absorption and desorption analysis, confirmed the successful synthesis of a mesoporous heterojunction material. The La3+-doping as well as the porous morphologies and larger specific surface area of the O-doped g-C3N4 ultimately improve the photocatalytic abilities via a proposed Z-scheme heterojunction mechanism. The roles of La3+-doping and morphology modification in promoting the separation of the photogenerated carriers and broadening the optical absorption range were experimentally discussed. The RhB degradation experiment indicated that the La-BiVO4/O-doped g-C3N4 powder has excellent photocatalytic activity, which is about 2.85 and 2 times higher than that of the pure BiVO4 and O-doped g-C3N4, respectively. Meanwhile, the La-BiVO4/O-doped g-C3N4 NF shows good stability and recoverability after a 10-cycle testing. Such a hybrid photocatalyst with a proposed Z-scheme heterojunction mechanism and good plasticity might pave a feasible way to fabricate a new library of photocatalysts.

19.
J Med Chem ; 66(11): 7438-7453, 2023 06 08.
Artigo em Inglês | MEDLINE | ID: mdl-37220310

RESUMO

Abnormal activation of fibroblast growth factor receptors (FGFRs) results in the development and progression of human cancers. FGFR2 is frequently amplified or mutated in cancers; therefore, it is an attractive target for tumor therapy. Despite the development of several pan-FGFR inhibitors, their long-term therapeutic efficacy is hindered by acquired mutations and low isoform selectivity. Herein, we report the discovery of an efficient and selective FGFR2 proteolysis-targeting chimeric molecule, LC-MB12, that incorporates an essential rigid linker. LC-MB12 preferentially internalizes and degrades membrane-bound FGFR2 among the four FGFR isoforms; this may promote greater clinical benefits. LC-MB12 exhibits superior potency in FGFR signaling suppression and anti-proliferative activity compared to the parental inhibitor. Furthermore, LC-MB12 is orally bioavailable and shows significant antitumor effects in FGFR2-dependent gastric cancer in vivo. Taken together, LC-MB12 is a candidate FGFR2 degrader for alternative FGFR2-targeting strategies and offers a promising starting point for drug development.


Assuntos
Neoplasias Gástricas , Humanos , Neoplasias Gástricas/patologia , Receptor Tipo 2 de Fator de Crescimento de Fibroblastos , Mutação , Transdução de Sinais , Inibidores de Proteínas Quinases/farmacologia , Fosforilação , Linhagem Celular Tumoral
20.
Eur J Med Chem ; 253: 115305, 2023 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-37023678

RESUMO

Src homology 2 domain-containing phosphatase 2 (SHP2) is a cytoplasmic protein tyrosine phosphatase (PTP) that regulates signal transduction of receptor tyrosine kinases (RTKs). Abnormal SHP2 activity is associated with tumorigenesis and metastasis. Because SHP2 contains multiple allosteric sites, identifying inhibitors at specific allosteric binding sites remains challenging. Here, we used structure-based virtual screening to directly search for the SHP2 "tunnel site" allosteric inhibitor. A novel hit (70) was identified as the SHP2 allosteric inhibitor with an IC50 of 10.2 µM against full-length SHP2. Derivatization of hit compound 70 using molecular modeling-guided structure-based modification allowed the discovery of an effective and selective SHP2 inhibitor, compound 129, with 122-fold improved potency compared to the hit. Further studies revealed that 129 effectively inhibited signaling in multiple RTK-driven cancers and RTK inhibitor-resistant cancer cells. Remarkably, 129 was orally bioavailable (F = 55%) and significantly inhibited tumor growth in haematological malignancy. Taken together, compound 129 developed in this study may serve as a promising lead or candidate for cancers bearing RTK oncogenic drivers and SHP2-related diseases.


Assuntos
Neoplasias , Transdução de Sinais , Humanos , Receptores Proteína Tirosina Quinases/metabolismo , Sítio Alostérico , Carcinogênese , Proteína Tirosina Fosfatase não Receptora Tipo 11 , Inibidores Enzimáticos/farmacologia , Inibidores Enzimáticos/química
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