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1.
Mol Pharm ; 21(1): 113-125, 2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-38081040

RESUMO

Although chemotherapy remains the standard therapy for tumor treatment, serious side effects can occur because of nontargeted distribution and damage to healthy tissues. Hollow mesoporous silica nanoparticles (HMSNs) modified with lipids offer potential as delivery systems to improve therapeutic outcomes and reduce adverse effects. Herein, we synthesized HMSNs with integrated disulfide bonds (HMSN) for loading with the chemotherapeutic agent oxaliplatin (OXP) which were then covered with the synthesized hypoxia-sensitive lipid (Lip) on the surface to prepare the dual-sensitive lipid-composite nanoparticles (HMSN-OXP-Lip). The empty lipid-composite nanoparticles (HMSN-Lip) would consume glutathione (GSH) in cells because of the reduction of disulfide bonds in HMSN and would also inhibit GSH production because of NADPH depletion driven by Lip cleavage. These actions contribute to increased levels of ROS that induce the immunogenic cell death (ICD) effect. Simultaneously, HMSN-Lip would disintegrate in the presence of high concentrations of GSH. The lipid in HMSN-OXP-Lip could evade payload leakage during blood circulation and accelerate the release of the OXP in the tumor region in the hypoxic microenvironment, which could significantly induce the ICD effect to activate an immune response for an enhanced therapeutic effect. The tumor inhibitory rate of HMSN-OXP-Lip was almost twice that of free OXP, and no apparent side effects were observed. This design provides a dual-sensitive and efficient strategy for tumor therapy by using lipid-composite nanoparticles that can undergo sensitive drug release and biodegradation.


Assuntos
Neoplasias da Mama , Neuropatia Hereditária Motora e Sensorial , Nanopartículas , Humanos , Feminino , Doxorrubicina , Morte Celular Imunogênica , Nanopartículas/química , Dióxido de Silício/química , Glutationa , Lipídeos , Neuropatia Hereditária Motora e Sensorial/tratamento farmacológico , Neoplasias da Mama/tratamento farmacológico , Dissulfetos , Linhagem Celular Tumoral , Microambiente Tumoral
2.
Biomacromolecules ; 25(2): 964-974, 2024 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-38232296

RESUMO

Thermosensitive nanoparticles can be activated by externally applying heat, either through laser irradiation or magnetic fields, to trigger the release of drug payloads. This controlled release mechanism ensures that drugs are specifically released at the tumor site, maximizing their effectiveness while minimizing systemic toxicity and adverse effects. However, its efficacy is limited by the low concentration of drugs at action sites, which is caused by no specific target to tumor sties. Herein, hyaluronic acid (HA), a gooey, slippery substance with CD44-targeting ability, was conjugated with a thermosensitive polymer poly(acrylamide-co-acrylonitrile) to produce tumor-targeting and thermosensitive polymeric nanocarrier (HA-P) with an upper critical solution temperature (UCST) at 45 °C, which further coloaded chemo-drug doxorubicin (DOX) and photosensitizer Indocyanine green (ICG) to prepare thermosensitive nanoreactors HA-P/DOX&ICG. With photosensitizer ICG acting as the "temperature control element", HA-P/DOX&ICG nanoparticles can respond to temperature changes when receiving near-infrared irradiation and realize subsequent structure depolymerization for burst drug release when the ambient temperature was above 45 °C, achieving programmable and on-demand drug release for effective antitumor therapy. Tumor inhibition rate increased from 61.8 to 95.9% after laser irradiation. Furthermore, the prepared HA-P/DOX&ICG nanoparticles possess imaging properties, with ICG acting as a probe, enabling real-time monitoring of drug distribution and therapeutic response, facilitating precise treatment evaluation. These results provide enlightenment for the design of active tumor targeting and NIR-triggered programmable and on-demand drug release of thermosensitive nanoreactors for tumor therapy.


Assuntos
Hipertermia Induzida , Nanopartículas , Neoplasias , Humanos , Fármacos Fotossensibilizantes/uso terapêutico , Hipertermia Induzida/métodos , Fototerapia/métodos , Doxorrubicina/química , Nanopartículas/química , Neoplasias/tratamento farmacológico , Neoplasias/patologia , Verde de Indocianina/farmacologia , Verde de Indocianina/química , Nanotecnologia , Liberação Controlada de Fármacos , Linhagem Celular Tumoral
3.
Org Biomol Chem ; 22(25): 5112-5116, 2024 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-38864433

RESUMO

An air-stable quinoline-derived NNP ligand chelated Mn catalyst was developed for the efficient α-alkylation of ketones with primary alcohols via a hydrogen auto-transfer methodology. The sole by-product formed is water, rendering the protocol atom efficient. A wide range of ketone and alcohol substrates were employed, providing the α-alkylated ketones with isolated yields up to 94%. This system was also efficient for the green synthesis of quinoline derivatives while using (2-aminophenyl)methanol as an alkylating reagent.

4.
Cell Mol Biol (Noisy-le-grand) ; 70(8): 175-181, 2024 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-39262244

RESUMO

The current research was designed to investigate the impact of whole-process high-quality nursing on acute pancreatitis (AP) patients' quality of life as well as the mechanism of miR-126-5p/HOXC8 axis promoting AP progression. One hundred AP patients admitted to our hospital were chosen and separated into control group (CG, n=50) and study group (SG, n=50). The CG took the routine nursing, while the SG adopted the whole-process high-quality nursing. Besides, cerulein (CE) was treated in AR42J cells to establish an experimental model of AP. The proliferation, apoptosis along with inflammation of CE-treated AR42J cells were assessed. The outcomes manifested that in contrast to the CG, the recovery time of bowel sound, the improvement time of abdominal distension, the improvement time of abdominal pain, the exhaust time and the defecation time in the SG presented shorter, the anxiety and depression scores in the SG presented lower, the WHOQOL-100 scores of patients in the SG presented higher in the fields of physiology, psychology, environment and social relations, the total incidence of complications of the SG presented lower, and the total nursing satisfaction of the SG was better. Besides, miR-126-5p presented upregulation in CE-stimulated AR42J cells, and miR-126-5p inhibition increased the proliferation along with repressed the apoptosis and inflammation in CE-stimulated AR42J cells. Moreover, HOXC8 could be the target mRNA of miR-126-5p, and HOXC8 elevation promoted the proliferation along with repressed the apoptosis and inflammation in CE-stimulated AR42J cells. In addition, rescue assays further validated that HOXC8 silence offset the protective impact of miR-126-5p repression on AP cell damage. In conclusion, our study indicated that whole-process high-quality nursing could promote the quality of life of AP patients, and revealed that miR-126-5p inhibition relieved CE-stimulated AR42J cells injury caused by AP via targeting HOXC8. Our study might offer novel insights for AP treatment and nursing.


Assuntos
Apoptose , Progressão da Doença , Proteínas de Homeodomínio , MicroRNAs , Pancreatite , Qualidade de Vida , MicroRNAs/genética , MicroRNAs/metabolismo , Humanos , Pancreatite/patologia , Pancreatite/genética , Masculino , Proteínas de Homeodomínio/metabolismo , Proteínas de Homeodomínio/genética , Apoptose/genética , Feminino , Proliferação de Células , Pessoa de Meia-Idade , Doença Aguda , Adulto , Ratos , Animais
5.
J Biochem Mol Toxicol ; 38(3): e23681, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38444083

RESUMO

Recent studies have shown that epithelial-mesenchymal transition (EMT) plays an important role in paraquat (PQ)-induced tissue fibrosis, which is the main cause of death in patients with PQ poisoning. However, no effective treatment for pulmonary interstitial fibrosis caused by PQ poisoning exists. It is of great significance for us to find new therapeutic targets through bioinformatics in PQ-induced EMT. We conducted transcriptome sequencing to determine the expression profiles of 1210 messenger RNAs (mRNAs), 558 long noncoding RNAs, 28 microRNAs (miRNAs), including 18 known-miRNAs, 10 novel-miRNAs and 154 circular RNAs in the PQ-exposed EMT group mice. Using gene ontology and Kyoto Encyclopaedia of Genes and Genomes analyses, we identified the pathways associated with signal transduction, cancers, endocrine systems and immune systems were involved in PQ-induced EMT. Furthermore, we constructed long noncoding RNA-miRNA-mRNA interrelated networks and found that upregulated genes included Il22ra2, Mdm4, Slc35e2 and Angptl4, and downregulated genes included RGS2, Gabpb2, Acvr1, Prkd3, Sp100, Tlr12, Syt15 and Camk2d. Thirteen new potential competitive endogenous RNA targets were also identified for further treatment of PQ-induced pulmonary tissue fibrosis. Through further study of the pathway and networks, we may identify new molecular targets in PQ-induced pulmonary EMT.


Assuntos
MicroRNAs , Fibrose Pulmonar , RNA Longo não Codificante , Humanos , Animais , Camundongos , MicroRNAs/genética , Paraquat/toxicidade , RNA Endógeno Competitivo , Sequenciamento de Nucleotídeos em Larga Escala , Transição Epitelial-Mesenquimal , RNA Mensageiro
6.
BMC Public Health ; 24(1): 2259, 2024 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-39164696

RESUMO

BACKGROUND: Metabolic syndrome (MetS) is a risk factor for cardiovascular disease (CVD), and CVD is a major challenge for cancer patients. This study aimed to investigate the prevalence and association of MetS and CVD among adult cancer patients. METHODS: This cross-sectional study included cancer patients aged > 18 years from the National Health and Nutrition Examination Survey (NHANES) from 2007 to 2018. The prevalence of MetS and CVD was calculated using weighted analysis. Multivariable logistic regression was used to assess the association between MetS and CVD. RESULTS: The study included 2658 adult cancer patients, of whom 1260 exhibited MetS and 636 had CVD. The weighted prevalence of MetS and CVD in cancer patients was 45.44%, and 19.23%, respectively. Multivariable logistic regression showed a 79% increased risk in higher CVD prevalence in cancer patients with MetS, with the OR (95% CI) of 1.79 (1.31, 2.44). Notably, obesity, elevated blood pressure (BP), high glucose, and low high density lipoprotein cholesterol (HDL-C) in the MetS components were significantly associated with higher CVD prevalence after adjusting for covariates. Moreover, the risk of CVD prevalence in cancer patients increased with more MetS components. Notably, MetS was more strongly linked to CVD in patients aged < 65 and women. CONCLUSIONS: Among adult cancer patients, over two-fifths (45.44%) were estimated to have MetS, while about one-fifth (19.23%) were considered to have CVD. Notably, obesity, elevated BP, high glucose, low HDL-C, and higher number of MetS components were found to be significantly associated with higher CVD prevalence among cancer adults. Cancer patients under 65 and women with MetS may be at increased risk of CVD.


Assuntos
Doenças Cardiovasculares , Síndrome Metabólica , Neoplasias , Inquéritos Nutricionais , Humanos , Feminino , Masculino , Síndrome Metabólica/epidemiologia , Neoplasias/epidemiologia , Neoplasias/complicações , Estudos Transversais , Pessoa de Meia-Idade , Doenças Cardiovasculares/epidemiologia , Adulto , Prevalência , Idoso , Fatores de Risco , Estados Unidos/epidemiologia , Adulto Jovem
7.
J Environ Sci (China) ; 139: 123-137, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38105041

RESUMO

The fate of 2-nitrobenzaldehyde (2-NBA) is of interest in atmospheric chemistry as it is a semi-volatile organic compound with high photosensitivity. This study presents a quantum chemical study of the gas-phase reactions of 2-NBA photo-excitation and OH-oxidation in the absence and presence of small TiO2 clusters. To further understand the unknown photolysis mechanism, the photo-reaction pathways of ground singlet state and the lying excited triplet state of 2-NBA were investigated including the initial and subsequent reactions of proton transfer, direct CO, NO2, and HCO elimination routes in the presence of O2 and NO. Meanwhile, the OH-mediated degradation of 2-NBA proceeded via five H-extraction and six OH-addition channels by indirect mechanism, which follows a succession of reaction steps initiated by the formation of weakly stable intermediate complexes. The H-extraction from the -CHO group was the dominant pathway with a negative activation energy of -1.22 kcal/mol. The calculated rate coefficients at 200-600 K were close to the experimental data in literature within 308-352 K, and the kinetic negative temperature independence was found in both experimental literature and computational results. Interestingly, 2-NBA was favored to be captured onto small TiO2 clusters via six adsorption configurations formed via various combination of three types of bonds of Ti···O, Ti···C, and O···H between the molecularly adsorbed 2-NBA and TiO2 clusters. Comparison indicted that the chemisorptions of aldehyde oxygen have largest energies. The results suggested adsorption conformations have a respectable impact on the catalysis barrier. This study is significant for understanding the atmospheric chemistry of 2-nitrobenzaldehyde.


Assuntos
Oxigênio , Adsorção , Temperatura , Oxigênio/química , Catálise
8.
Chemphyschem ; 24(10): e202300021, 2023 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-36781393

RESUMO

The degradation and transformation of iodinated alkanes are crucial in the iodine chemical cycle in the marine boundary layer. In this study, MP2 and CCSD(T) methods were adopted to study the atmospheric transformation mechanism and degradation kinetic properties of CH3 I and CH3 CH2 I mediated by ⋅OH radical. The results show that there are three reaction mechanisms including H-abstraction, I-substitution and I-abstraction. The H-abstraction channel producing ⋅CH2 I and CH3 C ⋅ HI radicals are the main degradation pathways of CH3 I and CH3 CH2 I, respectively. By means of the variational transition state theory and small curvature tunnel correction method, the rate constants and branching ratios of each reaction are calculated in the temperature range of 200-600 K. The results show that the tunneling effect contributes more to the reaction at low temperatures. Theoretical reaction rate constants of CH3 I and CH3 CH2 I with ⋅OH are calculated to be 1.42×10-13 and 4.44×10-13  cm3 molecule-1 s-1 at T=298 K, respectively, which are in good agreement with the experimental values. The atmospheric lifetimes of CH3 I and CH3 CH2 I are evaluated to be 81.51 and 26.07 day, respectively. The subsequent evolution mechanism of ⋅CH2 I and CH3 C ⋅ HI in the presence of O2 , NO and HO2 indicates that HCHO, CH3 CHO, and I-atom are the main transformation end-products. This study provides a theoretical basis for insight into the diurnal conversion and environmental implications of iodinated alkanes.

9.
Mol Pharm ; 20(10): 5078-5089, 2023 10 02.
Artigo em Inglês | MEDLINE | ID: mdl-37728215

RESUMO

The abnormal tumor blood vessels with high leakage can promote tumor cells to infiltrate into the systemic circulation and increase the risk of tumor metastasis. In addition, chemotherapy may destroy tumor blood vessels and further aggravate metastasis. Normalizing tumor blood vessels can reduce vascular leakage and increase vascular integrity. The simultaneous administration of vascular normalization drugs and chemotherapy drugs may resist the blood vessels' destruction of chemotherapy. Here, multifunctional nanoparticles (CCM@LMSN/DOX&St), which combined chemotherapy with tumor blood vessel normalization, were prepared for the treatment of breast cancer. The results showed that CCM@LMSN/DOX&St-loaded sunitinib (St) promoted the expression of junction proteins Claudin-4 and VE-cadherin of endothelial cells, reversed the destruction of DOX to the endothelial cell layer, protected the integrity of the endothelial cell layer, and inhibited the migration of 4T1 tumor cells across the endothelial cell layer. In vivo experiments showed that CCM@LMSN/DOX&St effectively inhibited tumor growth in situ; what is exciting was that it also inhibited distal metastasis of breast cancer. CCM@LMSN/DOX&St encapsulated with St can normalize tumor blood vessels, reverse the damage of DOX to tumor blood vessels, increase the integrity of blood vessels, and prevent tumor cell invasion into blood vessels, which can inhibit breast cancer spontaneous metastasis and reduce chemotherapy-induced metastasis. This drug delivery platform effectively inhibited the progression of tumors and provided a promising solution for effective tumor treatment.


Assuntos
Neoplasias da Mama , Nanopartículas Multifuncionais , Nanopartículas , Humanos , Feminino , Neoplasias da Mama/patologia , Doxorrubicina , Células Endoteliais/metabolismo , Linhagem Celular Tumoral , Melanoma Maligno Cutâneo
10.
Biomacromolecules ; 24(11): 4731-4742, 2023 11 13.
Artigo em Inglês | MEDLINE | ID: mdl-37672635

RESUMO

The tumor microenvironment (TME) of breast cancer is hypoxic, which can promote tumor progression, including invasion and metastasis, and limit the efficacy of anti-tumor treatment. Nitric oxide (NO) can dilate blood vessels, effectively alleviate hypoxia, and regulate the TME, which has the potential to improve the anti-tumor therapeutic efficacy. Here, chitosan (CO) and octadecylamine (ODA) were linked by the disulfide bond, and the LinTT1 peptide was linked onto CO-SS-ODA for targeting tumor cells and endothelial cells in tumors. The NO donor S-nitroso-N-acetylpenicillamine (SNAP) was connected to CO. Doxorubicin (DOX) was encapsulated, and GSH hierarchically responsive polymer micelles (TSCO-SS-ODA/DOX) were constructed for the treatment of breast cancer. The micelles had differently responsive drug release in different GSH concentrations. In endothelial cells, the micelles rapidly responded to release NO. In tumor cells, the disulfide bond rapidly broke and released DOX to effectively kill tumor cells. The disulfide bond was not sensitive to GSH concentration in endothelial cells, which had less release of DOX. The killing effect of the micelles to endothelial cells was much lower than that to tumor cells. The cell selective drug release of the drug delivery systems enabled safe and effective treatment of drugs. TSCO-SS-ODA/DOX, which had the excellent ability to target tumors, can alleviate tumor hypoxia, decrease the infiltration of M2 macrophages in tumors, increase the infiltration of M1 macrophages in tumors, and remodel the TME. Notably, TSCO-SS-ODA/DOX can significantly inhibit the growth of the primary tumor and effectively inhibit tumor metastasis. The drug delivery system provided a potential solution for effectively treating breast cancer.


Assuntos
Neoplasias da Mama , Humanos , Feminino , Neoplasias da Mama/tratamento farmacológico , Micelas , Células Endoteliais , Microambiente Tumoral , Doxorrubicina/química , Polímeros/química , Dissulfetos , Concentração de Íons de Hidrogênio
11.
J Phys Chem A ; 127(25): 5402-5413, 2023 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-37311006

RESUMO

Nitrous acid (HONO) is hazardous to the human respiratory system, and the hydrolysis of NO2 is the source of HONO. Hence, the investigation on the removal and transformation of HONO is urgently established. The effects of amide on the mechanism and kinetics of the formation of HONO with acetamide, formamide, methylformamide, urea, and its clusters of the catalyst were studied theoretically. The results show that amide and its small clusters reduce the energy barrier, the substituent improves the catalytic efficiency, and the catalytic effect order is dimer > monohydrate > monomer. Meanwhile, the clusters composed of nitric acid (HNO3), amides, and 1-6 water molecules were investigated in the amide-assisted nitrogen dioxide (NO2) hydrolysis reaction after HONO decomposes by combining the system sampling technique and density functional theory. The study on thermodynamics, intermolecular forces, optics properties of the clusters, as well as the influence of humidity, temperature, atmospheric pressure, and altitude shows that amide molecules promote the clustering and enhance the optical properties. The substituent facilitates the clustering of amide and nitric acid hydrate and lowers the humidity sensitivity of the clusters. The findings will help to control the atmospheric aerosol particle and then reduce the harm of poisonous organic chemicals on human health.

12.
BMC Ophthalmol ; 23(1): 455, 2023 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-37957614

RESUMO

PURPOSE: To evaluate the peripapillary retinal nerve fiber layer thickness (pRNFL) in patients with intracranial atherosclerotic stenosis (ICAS). METHODS: A cross-sectional study was performed in a general hospital. The intracranial atherosclerotic stenosis was evaluated by digital subtraction angiography (DSA), computed tomography angiography (CTA) or magnetic resonance angiography (MRA). High-definition optical coherence tomography (HD-OCT) was used to evaluate the peripapillary retinal nerve fiber layer thickness. RESULTS: A total of 102 patients, including 59(57.8%) patients with ICAS and 43(42.2%) patients without ICAS, were finally analysed in the study. The peripapillary retinal nerve fiber layer thickness (pRNFL) was reduced significantly in the average, the superior and the inferior quadrants of the ipsilateral eyes and in the superior quadrant of the contralateral eyes in patients with ICAS compared with patients without ICAS. After multivariate analysis, only the superior pRNFL thickness in the ipsilateral eyes was significantly associated with ICAS (OR,0.968; 95% CI,0.946-0.991; p = 0.006). The area under receiver operator curve was 0.679 (95% CI,0.576-0.782) for it to identify the presence of ICAS. The cut-off value of the superior pRNFL was 109.5 µm, and the sensitivity and specificity were 50.8% and 83.7%, respectively. CONCLUSION: The superior pRNFL in the ipsilateral eye was significantly associated with ICAS in this study. Larger studies are needed to explore the relation between pRNFL and ICAS further.


Assuntos
Arteriosclerose Intracraniana , Disco Óptico , Humanos , Células Ganglionares da Retina , Estudos Transversais , Constrição Patológica , Fibras Nervosas , Tomografia de Coerência Óptica/métodos , Arteriosclerose Intracraniana/complicações , Arteriosclerose Intracraniana/diagnóstico
13.
Medicina (Kaunas) ; 59(5)2023 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-37241194

RESUMO

Background and Objectives: Successful root canal treatment depends on the thorough removal of biofilms through chemomechanical preparation. This study aimed to investigate and compare the cleaning and disinfecting efficiency of oval-shaped root canals using XP-endo Shaper (XPS), ProTaper Next (PTN), and HyFlex CM (HCM) in combination with passive ultrasonic irrigation (PUI). Materials and Methods: Ninety extracted teeth were contaminated and randomly divided into three groups: XPS, PTN, and HCM. Each group was assigned to three subgroups: subgroup A (sterile saline), subgroup B (3% sodium hypochlorite and 17% ethylenediaminetetraacetic acid), and subgroup C (3% sodium hypochlorite, 17% ethylenediaminetetraacetic acid, and PUI). Bacterial sampling was conducted both from baseline samples and samples after chemomechanical preparation. Scanning electron microscopy (SEM) was used to evaluate the residue bacterial biofilms, hard tissue debris, and smear layers on the buccolingual walls of oval-shaped root canals. Results: When combined with sterile saline, XPS demonstrated a higher reduction of bacterial counts and was more effective in eradicating Enterococcus faecalis in the middle third of the canals compared to the other instruments (p < 0.05). Additionally, when used with antimicrobial irrigants, XPS was more effective in disinfecting the coronal third of the canals than the other instruments (p < 0.05). Furthermore, XPS reduced hard tissue debris more effectively in the middle third of canals than in the apical third (p < 0.05). Conclusions: XPS outperforms PTN and HCM in disinfecting oval-shaped root canals. Despite the fact that combining XPS and PUI improves cleaning and disinfecting, removing hard tissue debris from the critical apical area remains challenging.


Assuntos
Preparo de Canal Radicular , Hipoclorito de Sódio , Humanos , Hipoclorito de Sódio/uso terapêutico , Ácido Edético/uso terapêutico , Cavidade Pulpar , Ultrassom
14.
J Am Chem Soc ; 144(27): 12476-12487, 2022 07 13.
Artigo em Inglês | MEDLINE | ID: mdl-35767727

RESUMO

Inspired by the discovery of a S═N bond in the collagen IV network and its essential role in stabilizing basement membranes, sulfilimines have drawn much attention in the fields of chemistry and biology. However, their further uptake is hindered by the lack of mild, efficient, and environmentally benign protocols by which sulfilimines can be constructed under biomolecule-compatible conditions. Here, we report a terminal oxidant-free copper-catalyzed dehydrogenative Chan-Lam coupling of free diaryl sulfilimines with arylboronic acids with excellent chemoselectivity and broad substrate compatibility. The mild reaction conditions and biomolecule-compatible nature allow the employment of this protocol in the late-stage functionalization of complex peptides, and more importantly, as an effective bioconjugation method as showcased in a model protein. A combined experimental and computational mechanistic investigation reveals that an inner-sphere electron-transfer process circumvents the sacrificial oxidant employed in traditional Chan-Lam coupling reactions. An energetically viable concerted pathway was located wherein a copper hydride facilitates hydrogen-atom abstraction from the isopropanol solvent to produce dihydrogen via a four-membered transition state.


Assuntos
Cobre , Hidrogênio , Cobre/química , Transporte de Elétrons , Iminas , Proteínas
15.
Int J Mol Sci ; 23(17)2022 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-36077260

RESUMO

The influence of phosphates on the transport of plastic particles in porous media is environmentally relevant due to their ubiquitous coexistence in the subsurface environment. This study investigated the transport of plastic nanoparticles (PNPs) via column experiments, paired with Derjaguin-Landau-Verwey-Overbeek calculations and numerical simulations. The trends of PNP transport vary with increasing concentrations of NaH2PO4 and Na2HPO4 due to the coupled effects of increased electrostatic repulsion, the competition for retention sites, and the compression of the double layer. Higher pH tends to increase PNP transport due to the enhanced deprotonation of surfaces. The release of retained PNPs under reduced IS and increased pH is limited because most of the PNPs were irreversibly captured in deep primary minima. The presence of physicochemical heterogeneities on solid surfaces can reduce PNP transport and increase the sensitivity of the transport to IS. Furthermore, variations in the hydrogen bonding when the two phosphates act as proton donors will result in different influences on PNP transport at the same IS. This study highlights the sensitivity of PNP transport to phosphates associated with the solution chemistries (e.g., IS and pH) and is helpful for better understanding the fate of PNPs and other colloidal contaminants in the subsurface environment.


Assuntos
Nanopartículas , Dióxido de Silício , Concentração de Íons de Hidrogênio , Microplásticos , Concentração Osmolar , Fosfatos , Porosidade
16.
Molecules ; 27(9)2022 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-35566331

RESUMO

Colorectal cancer (CRC) is a usual digestive tract malignancy and the third main cause of cancer death around the world, with a high occurrence rate and mortality rate. Conventional therapies for CRC have certain side effects and restrictions. However, the exciting thing is that with the rapid development of nanotechnology, nanoparticles have gradually become more valuable drug delivery systems than traditional therapies because of their capacity to control drug release and target CRC. This also promotes the application of nano-drug targeted delivery systems in the therapy of CRC. Moreover, to make nanoparticles have a better colon targeting effect, many approaches have been used, including nanoparticles targeting CRC and in response to environmental signals. In this review, we focus on various targeting mechanisms of CRC-targeted nanoparticles and their latest research progress in the last three years, hoping to give researchers some inspiration on the design of CRC-targeted nanoparticles.


Assuntos
Neoplasias Colorretais , Nanopartículas , Neoplasias Colorretais/tratamento farmacológico , Sistemas de Liberação de Medicamentos , Humanos , Sistemas de Liberação de Fármacos por Nanopartículas , Nanopartículas/uso terapêutico , Nanotecnologia
17.
AAPS PharmSciTech ; 23(6): 167, 2022 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-35711068

RESUMO

Hypoxia is an important pathological phenomenon, and it can induce many tumor microenvironment changes, such as accumulations of intracellular lactic acid, decrease of tumor microenvironment pH value, and regulate a series of physiological and pathological processes such as adhesion, metastasis, and immune escape. Hypoxic tumor cells act as a key target for treating tumor. In this research, we designed and prepared PEG-nitroimidazole grafts, PEG-NI, and FA-PEG-NI. We first explored their physical and chemical properties to serve as a drug carrier. Then, the hypoxia-sensitive properties such as particle size changes and drug release were investigated. Finally, the tumor targeting ability was studied in vitro and in vivo, and anti-tumor capacity was determined. Both grafts showed excellent property as a nanodrug carrier and showed favorable drug encapsulation ability of sorafenib with the help of the hydrophobic chain of 6-(BOC-amino) hexyl bromide. The micelles responded to the hypoxic tumor environment with chemical and spatial structure changes leading to sensitive and fast drug release. With the modification of folic acid, FA-PEG-NI gained tumor targeting ability in vivo. FA-PEG-NI graft proved a potential targeting drug delivery system in the treatment of hypoxic hepatocellular carcinoma.


Assuntos
Antineoplásicos , Carcinoma Hepatocelular , Neoplasias Hepáticas , Nitroimidazóis , Antineoplásicos/química , Carcinoma Hepatocelular/tratamento farmacológico , Linhagem Celular Tumoral , Portadores de Fármacos/química , Sistemas de Liberação de Medicamentos , Ácido Fólico/química , Humanos , Hipóxia/tratamento farmacológico , Neoplasias Hepáticas/tratamento farmacológico , Micelas , Polietilenoglicóis/química , Microambiente Tumoral
18.
Biochem Biophys Res Commun ; 553: 172-179, 2021 05 14.
Artigo em Inglês | MEDLINE | ID: mdl-33773140

RESUMO

BACKGROUND: Cardiac fibrosis will increase wall stiffness and diastolic dysfunction, which will eventually lead to heart failure. Asenapine maleate (AM) is widely used in the treatment of schizophrenia. In the current study, we explored the potential mechanism underlying the role of AM in angiotensin II (Ang II)-induced cardiac fibrosis. METHODS: Cardiac fibroblasts (CFs) were stimulated using Ang II with or without AM. Cell proliferation was measured using the cell counting kit-8 assay and the Cell-Light EdU Apollo567 In Vitro Kit. The expression levels of proliferating cell nuclear antigen (PCNA) and α-smooth muscle actin (α-SMA) were detected using immunofluorescence or western blotting. At the protein level, the expression levels of the components of the transforming growth factor beta 1 (TGFß1)/mitogen-activated protein kinase (MAPK) signaling pathway were also detected. RESULTS: After Ang II stimulation, TGFß1, TGFß1 receptor, α-SMA, fibronectin (Fn), collagen type I (Col1), and collagen type III (Col3) mRNA levels increased; the TGFß1/MAPK signaling pathway was activated in CFs. After AM pretreatment, cell proliferation was inhibited, the numbers of PCNA -positive cells and the levels of cardiac fibrosis markers decreased. The activity of the TGFß1/MAPK signaling pathway was also inhibited. Therefore, AM can inhibit cardiac fibrosis by blocking the Ang II-induced activation through TGFß1/MAPK signaling pathway. CONCLUSIONS: This is the first report to demonstrate that AM can inhibit Ang II-induced cardiac fibrosis by down-regulating the TGFß1/MAPK signaling pathway. In this process, AM inhibited the proliferation and activation of CFs and reduced the levels of cardiac fibrosis markers. Thus, AM represents a potential treatment strategy for cardiac fibrosis.


Assuntos
Angiotensina II/farmacologia , Dibenzocicloeptenos/farmacologia , Fibroblastos/efeitos dos fármacos , Fibroblastos/metabolismo , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Fator de Crescimento Transformador beta1/metabolismo , Animais , Diferenciação Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Fibroblastos/citologia , Fibrose/metabolismo , Fibrose/prevenção & controle , Miocárdio/citologia , Miocárdio/metabolismo , Ratos , Ratos Wistar , Esquizofrenia/tratamento farmacológico
19.
Mol Pharm ; 18(11): 3966-3978, 2021 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-34579532

RESUMO

Stemness and metastasis are the two main challenges in cancer therapy and are related to disease relapse post-treatment. They both have a strong correlation with chemoresistance and poor prognosis, ultimately leading to treatment failure. It has been reported that chemotherapy can induce stemness and metastasis in many cancer types, especially treatment with the chemotherapeutic agent doxorubicin (DOX) in breast cancer. A combination treatment is an efficient and elegant approach in cancer therapy through simultaneous delivery of two or more drugs with a delivery system for its synergistic effect, which is not an additive of two individual drugs. Herein, we report a combinatorial system with DOX and all-trans retinoic acid (ATRA) to address both of the above issues. As a common critical regulatory factor for oncogenic signal transduction pathways, Pin1 is a specific isomerase highly expressed within various tumor cells. ATRA, a newly identified Pin1 inhibitor, can abolish several oncogenic pathways by effectively inhibiting and degrading overexpressed Pin1. We successfully developed a folic acid (FA)-modified chitosan (CSO)-derived polymer (FA-CSOSA) and obtained FA-CSOSA/DOX and FA-CSOSA/ATRA drug-loaded micelles. FA modification can improve the uptake of the nanoparticles in tumor cells and tumor sites via folate receptor-mediated cell internalization. Compared to treatment with DOX alone, the combined treatment induced 4T1 cell apoptosis in a synergistic manner. Reduced stemness-related protein expression and inhibited metastasis were observed during treatment with FA-CSOSA/DOX and FA-CSOSA/ATRA and were found to be associated with Pin1. Further in vivo experiments showed that treatment with FA-CSOSA/DOX and FA-CSOSA/ATRA resulted in 85.5% tumor inhibition, which was 2.5-fold greater than that of cells treated with DOX·HCl alone. This work presents a new paradigm for addressing chemotherapy-induced side effects via degradation of Pin1 induced by tumor-targeted delivery of DOX and ATRA.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Neoplasias da Mama/tratamento farmacológico , Doxorrubicina/administração & dosagem , Sistemas de Liberação de Fármacos por Nanopartículas/química , Tretinoína/administração & dosagem , Animais , Protocolos de Quimioterapia Combinada Antineoplásica/farmacocinética , Apoptose/efeitos dos fármacos , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Quitosana/química , Modelos Animais de Doenças , Doxorrubicina/farmacocinética , Liberação Controlada de Fármacos , Sinergismo Farmacológico , Feminino , Ácido Fólico/química , Técnicas de Silenciamento de Genes , Humanos , Camundongos , Micelas , Peptidilprolil Isomerase de Interação com NIMA/antagonistas & inibidores , Peptidilprolil Isomerase de Interação com NIMA/genética , Peptidilprolil Isomerase de Interação com NIMA/metabolismo , Células-Tronco Neoplásicas/efeitos dos fármacos , Células-Tronco Neoplásicas/patologia , Distribuição Tecidual , Tretinoína/farmacocinética
20.
Arch Pharm (Weinheim) ; 354(2): e2000266, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32986279

RESUMO

Methicillin-resistant Staphylococcus aureus (MRSA), one of the major and most dangerous pathogens in humans, is a causative agent of severe pandemic of mainly skin and soft tissue and occasionally fatal infections. Therefore, it is imperative to develop potent and novel anti-MRSA agents. Indole derivatives could act against diverse enzymes and receptors in bacteria, occupying a salient place in the development of novel antibacterial agents. Dimerization and hybridization are common strategies to discover new drugs, and a number of indole dimers and hybrids possess potential antibacterial activity against a panel of clinically important pathogens including MRSA. Accordingly, indole dimers and hybrids are privileged scaffolds for the discovery of novel anti-MRSA agents. This review outlines the recent development of indole dimers and hybrids with a potential activity against MRSA, covering articles published between 2010 and 2020. The structure-activity relationship and the mechanism of action are also discussed to facilitate further rational design of more effective candidates.


Assuntos
Antibacterianos/farmacologia , Indóis/farmacologia , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Antibacterianos/síntese química , Antibacterianos/química , Dimerização , Indóis/síntese química , Indóis/química , Testes de Sensibilidade Microbiana , Estrutura Molecular
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