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1.
J Am Chem Soc ; 144(14): 6558-6565, 2022 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-35357171

RESUMO

Separation of light hydrocarbons (C1-C9) represents one of the "seven chemical separations to change the world". Boron clusters can potentially play an important role in chemical separation, due to their unique three-dimensional structures and their ability to promote a potentially rich array of weak noncovalent interactions. Herein, we report the rational design of metallacages with carborane functionality and cooperative dihydrogen binding sites for the highly selective capture of cyclohexane molecules. The metallacage 1, bearing the ligand 2,4,6-tris(4-pyridyl)-1,3,5-triazine (TPT), can produce cyclohexane with a purity of 98.5% in a single adsorption-desorption cycle from an equimolar mixture of benzene and cyclohexane. In addition, cyclohexene molecules can be also encapsulated inside the metallacage 1. This selective encapsulation was attributed to spatial confinement effects, C-H···π interactions, and particularly dihydrogen-bond interactions. This work suggests exciting future applications of carborane cages in supramolecular chemistry for the selective adsorption and separation of alkane molecules and may open up a new research direction in host-guest chemistry.

2.
Mol Pharm ; 19(3): 819-830, 2022 03 07.
Artigo em Inglês | MEDLINE | ID: mdl-35170976

RESUMO

The emergence of superbacteria as well as the drug resistance of the current bacteria gives rise to worry regarding a bacterial pandemic and also calls for the development of novel ways to combat the bacteria. Here in this article, we demonstrate that mild hyperthermia induced by hollow mesoporous Prussian blue nanoparticles (HMPBNPs) in alliance with a low concentration of hydrogen peroxide (H2O2) shows a powerful inhibition effect on bacteria. Our results demonstrate that this therapeutic regime could realize almost full growth inhibition of both Gram-positive (Staphylococcus aureus, S. aureus) and -negative bacteria (Escherichia coli, E. coli), as well as potent inhibition/elimination of the S. aureus biofilm. The wound healing results indicate that combination regime of the antibacterial system could be conveniently used for wound disinfection in vivo and could promote wound healing. To our limited knowledge, this is one of the few pioneer works to apply mild hyperthermia for the combat of bacteria, which provides a novel strategy to inspire future studies.


Assuntos
Hipertermia Induzida , Nanopartículas , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Bactérias , Escherichia coli , Ferrocianetos , Peróxido de Hidrogênio/farmacologia , Staphylococcus aureus
3.
Adv Mater ; 33(41): e2103307, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34431574

RESUMO

Leber's hereditary optic neuropathy (LHON) is a rare inherited blindness caused by mutations in the mitochondrial DNA (mtDNA). The disorder is untreatable and tricky, as the existing chemotherapeutic agent Idebenone alleviates symptoms rather than overcoming the underlying cause. Although some studies have made progress on allotopic expression for LHON, in situ mitochondrial gene therapy remains challenging, which may simplify delivery procedures to be a promising therapeutic for LHON. LHON becomes more difficult to manage in the changed mitochondrial microenvironment, including increasing reactive oxygen species (ROS) and decreasing mitochondrial membrane potential (MMP). Herein, a pathologically responsive mitochondrial gene delivery vector named [triphenylphosphine-terminated poly(sulfur-containing thioketal undecafluorohexylamine histamine) and Ide-terminated poly(sulfur-containing thioketal undecafluorohexylamine histamine)] (TISUH) is reported to facilitate commendable in situ mitochondrial gene therapy for LHON. TISUH directly targets diseased mitochondria via triphenylphosphine and fluorination addressing the decreasing MMP. In addition, TISUH can be disassembled by high mitochondrial ROS levels to release functional genes for enhancing gene transfection efficiency and fundamentally correcting genetic abnormalities. In both traditional and gene-mutation-induced LHON mouse models, TISUH-mediated gene therapy shows satisfactory curative effect through the sustained therapeutic protein expression in vivo. This work proposes a novel pathologically responsive in situ mitochondrial delivery platform and provides a promising approach for refractory LHON as well as other mtDNA mutated diseases treatments.


Assuntos
Terapia Genética/métodos , Mitocôndrias/genética , Atrofia Óptica Hereditária de Leber/terapia , Animais , DNA/química , DNA Mitocondrial/genética , Modelos Animais de Doenças , Complexo I de Transporte de Elétrons/genética , Corantes Fluorescentes/química , Humanos , Potencial da Membrana Mitocondrial , Camundongos , Camundongos Endogâmicos BALB C , Mitocôndrias/fisiologia , Atrofia Óptica Hereditária de Leber/patologia , Polímeros/química , Subunidades Proteicas/genética , Espécies Reativas de Oxigênio/metabolismo , Ubiquinona/análogos & derivados , Ubiquinona/química
4.
J Am Chem Soc ; 143(13): 5099-5105, 2021 04 07.
Artigo em Inglês | MEDLINE | ID: mdl-33761746

RESUMO

The controllable B-H bond activation of carboranes has long been a compelling challenge. However, as the symmetry of para-carborane places the same charge on all of its ten boron atoms, controlling the regiochemistry of B-H bond activation in these molecules has remained out of reach ever since their discovery. Herein, we describe how to use steric effects to achieve a regioselective process for B-H activation of para-carborane. In this strategy, B(2,8)-H or B(2,7)-H activation patterns were achieved by taking advantage of the π-π interactions between pyridine ligands. Interestingly, by employing host-guest interactions in metallacage compounds, B(2,8)-H bond activation could be avoided and exclusive B(2,9)-H bond activation can be achieved. Steric hindrance was also found to be beneficial for regioselective B(2,8)-H bond activation in metallacage species. In this work, we demonstrate that steric effects can be a promising driving force for controllable activation of the B-H bonds of carboranes and open new opportunities in this field.

5.
Chem Commun (Camb) ; 57(19): 2412-2415, 2021 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-33554232

RESUMO

The introduction of the 2-pyridylsulfenyl directing group to o-carboranes allowed either B(3)-Ir or B(4)-Ir bond formation using a steric effect strategy. Moreover, the reactivity of the B(4)-Rh o-carborane complexes with small molecules was probed by reactions with N-bromosuccinimide, N-iodosuccinimide and O2. Rhodium-mediated B(4)-hydroxylation and B(4)-halogenation which are seldom reported have been achieved under practical and mild conditions.

6.
Dalton Trans ; 50(3): 1060-1068, 2021 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-33367445

RESUMO

Herein, we describe the synthesis of tetraphenylphosphonium o-carboranyl dithiocarboxylate (Ligand 1) and methyldithiocarboxyl-o-carborane (Ligand 2). The complexes [Cp*M(o-C2B10H11CS2)Cl] (M = Ir (3); Rh (4)) and [Cp*M(o-C2B10H11CS2)2] (M = Ir (5); Rh (6)) have been synthesized based on Ligand 1. The selective B-H bond activation of Ligand 2 has also been explored, leading to the synthesis of the B-H activated complex [Cp*Ir(o-C2B10H10CS2CH3)Cl] (7) and four of its substituted derivatives (8, 9, 10 and 11). All of these compounds have been characterised through single-crystal X-ray diffraction, NMR, IR spectroscopy and elemental analysis.

7.
Nat Commun ; 11(1): 5033, 2020 10 06.
Artigo em Inglês | MEDLINE | ID: mdl-33024092

RESUMO

Soaring cases of coronavirus disease (COVID-19) are pummeling the global health system. Overwhelmed health facilities have endeavored to mitigate the pandemic, but mortality of COVID-19 continues to increase. Here, we present a mortality risk prediction model for COVID-19 (MRPMC) that uses patients' clinical data on admission to stratify patients by mortality risk, which enables prediction of physiological deterioration and death up to 20 days in advance. This ensemble model is built using four machine learning methods including Logistic Regression, Support Vector Machine, Gradient Boosted Decision Tree, and Neural Network. We validate MRPMC in an internal validation cohort and two external validation cohorts, where it achieves an AUC of 0.9621 (95% CI: 0.9464-0.9778), 0.9760 (0.9613-0.9906), and 0.9246 (0.8763-0.9729), respectively. This model enables expeditious and accurate mortality risk stratification of patients with COVID-19, and potentially facilitates more responsive health systems that are conducive to high risk COVID-19 patients.


Assuntos
Infecções por Coronavirus/mortalidade , Aprendizado de Máquina , Pandemias , Pneumonia Viral/mortalidade , Idoso , Betacoronavirus , COVID-19 , China/epidemiologia , Feminino , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Redes Neurais de Computação , Medição de Risco , SARS-CoV-2 , Máquina de Vetores de Suporte
8.
J Am Chem Soc ; 142(18): 8532-8538, 2020 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-32271556

RESUMO

Herein, we describe how to utilize dihydrogen bond interactions to achieve alkane recognition and hexane isomer separation. A series of metallacycles based on carborane backbones are presented herein, revealing interdependent B-Hδ-···Hδ+-C proton-hydride interactions. The metallacycles take advantage of these dihydrogen bond interactions for the separation of hexane isomers. We show that the metallacycle 3a, bearing 1,4-di(4-pyridyl)benzene (DPB), can produce n-hexane with a purity of >99% in a single adsorption-desorption cycle from an equimolar mixture of all five isomers of hexane. The isomers 2-methylpentane and 3-methylpentane can be selectively absorbed by metallacycle 4a, which bears 1,2-di(4-pyridyl)ethylene (DPE). The size of the metallacycle, C-H···π interactions, and particularly B-Hδ-···Hδ+-C interactions are the main forces governing the extent of hexane recognition. This work provides a promising principle for the design of supramolecular coordination complexes (SCCs) for the separation of alkanes.

9.
World J Clin Cases ; 8(1): 54-67, 2020 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-31970170

RESUMO

BACKGROUND: Distant metastasis, particularly visceral metastasis (VM), represents an important negative prognostic factor for prostate cancer (PCa) patients. However, due to the lower rate of occurrence of VM, studies on these patients are relatively rare. Consequently, studies focusing on prognostic factors associated with PCa patients with VM are highly desirable. AIM: To investigate the prognostic factors for overall survival (OS) in PCa patients with lung, brain, and liver metastases, respectively, and evaluate the impact of site-specific and number-specific VM on OS. METHODS: Data on PCa patients with VM were extracted from the Surveillance, Epidemiology, and End Results database between 2010 and 2015. Univariate and multivariate Cox regression analyses were used to analyze the association between clinicopathological characteristics and survival of patients with different site-specific VM. Kaplan-Meier analyses and Log-rank tests were performed to analyze the differences among the groups. RESULTS: A total of 1358 PCa patients with site-specific VM were identified from 2010 to 2015. Older age (> 70 years) (P < 0.001), higher stage (T3/T4) (P = 0.004), and higher Gleason score (> 8) (P < 0.001) were found to be significant independent prognostic factors associated with poor OS in PCa patients with lung metastases. Higher stage (T3/T4) (P = 0.047) was noted to be the only independent risk factor affecting OS in PCa patients with brain metastases. Older age (> 70 years) (P = 0.010) and higher Gleason score (> 8) (P = 0.001) were associated with shorter OS in PCa patients with liver metastases. PCa patients with isolated lung metastases exhibited significantly better survival outcomes compared with PCa patients with other single sites of VM (P < 0.001). PCa patients with a single site of VM exhibited a superior OS compared with PCa patients with multiple sites of VM (P < 0.001). CONCLUSION: This is the first Surveillance, Epidemiology, and End Results-based study to determine prognostic factors affecting OS in PCa patients with different site-specific VM. Clinical assessments of these crucial prognostic factors become necessary before establishing a treatment strategy for these patients with metastatic PCa.

10.
Biomaterials ; 230: 119616, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31837823

RESUMO

As hepatic stellate cells (HSCs) are essential for hepatic fibrogenesis, HSCs targeted nano-drug delivery system is a research hotspot in liver fibrosis therapy. However, the excessive deposition of fibrosis collagen (mainly collagen I) in the space of Disse associated with hepatic fibrogenesis would significantly hinder nano-formulation delivery to HSCs. Here, we have prepared a collagenase I and retinol co-decorated polymeric micelle that possess nanodrill-like and HSCs-target function based on poly-(lactic-co-glycolic)-b-poly (ethylene glycol)-maleimide (PLGA-PEG-Mal) (named CRM) for liver fibrosis therapy. Upon encountering collagen I barrier, CRM exerted a nanodrill-like function, efficiently degrading pericellular collagen I and showing greater uptake by human HSCs than other micelle formulations. Besides, CRM could realize excellent accumulation in the fibrotic liver and accurate targeting to activated HSCs in mouse hepatic fibrosis model. Moreover, CRM loaded with nilotinib (CRM/NIL), a second-generation tyrosine kinase inhibitor used in the treatment of liver fibrosis, showed optimal antifibrotic activity. This work suggests that CRM with dual function is an efficient carrier for liver fibrosis drug delivery and collagenase I decorating could be a new strategy for building more efficient HSCs targeted nano-drug delivery system.


Assuntos
Cirrose Hepática , Micelas , Matriz Extracelular , Células Estreladas do Fígado/patologia , Humanos , Fígado/patologia , Cirrose Hepática/tratamento farmacológico , Cirrose Hepática/patologia
11.
J Control Release ; 309: 82-93, 2019 09 10.
Artigo em Inglês | MEDLINE | ID: mdl-31344426

RESUMO

Hypoxia is a potent tumor microenvironmental (TME) factor promoting immunosuppression and metastatic progression. For current anticancer therapeutic strategies, the combination of hypoxia alleviation and photodynamic therapy (PDT) might be a useful approach to further improve anticancer efficacy. In this study, we alleviated tumor hypoxia using a prolonged oxygen-generating phototherapy hydrogel (POP-Gel), which effectively elevated the oxygen level and shrank the hypoxic regions of tumors for up to 5 days evaluated by photoacoustic (PA) imaging and immunofluorescence staining, meeting the requirement of the "once injection, sustained treatment" strategy and significantly increasing PDT efficacy. The long-period improvement of the tumor hostile environment downregulated the expression of hypoxia inducible factor (HIF)-1α and vascular endothelial growth factor (VEGF), further preventing tumor growth and metastasis. More importantly, the enhanced PDT triggered a more intense immune response, improving the inhibition of triple negative breast cancer growth even tumor elimination. The POP-Gel may contribute useful insights into the combination of hypoxia alleviation and PDT.


Assuntos
Neoplasias da Mama/tratamento farmacológico , Hidrogéis/uso terapêutico , Oxigênio/uso terapêutico , Fármacos Fotossensibilizantes/uso terapêutico , Porfirinas/uso terapêutico , Hipóxia Tumoral/efeitos dos fármacos , Animais , Neoplasias da Mama/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Clorofilídeos , Feminino , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Fotoquimioterapia/métodos
12.
J Control Release ; 307: 44-54, 2019 08 10.
Artigo em Inglês | MEDLINE | ID: mdl-31202726

RESUMO

Hypoxia is the trickiest barrier for oncotherapy, which can cause the resistance of various tumor treatments, even promote cancer progression and metastasis, especially in the treatment of photodynamic therapy (PDT). Therefore, alleviating tumor hypoxia would be a favorable modality to improve PDT treatment. In this study, we designed an innovative biological oxygen-evolving material, autotrophic light-triggered green affording­oxygen engine (ALGAE), which could perform an on-off switchable and inexhaustible oxygen generation triggered by the same irradiation of PDT with good biocompatibility and degradability. And the hypoxia-resistant PDT induced by ALGAE could successfully eradicate tumors and avoid tumor metastasis. The ALGAE system could be standby in a long period for efficient oxygen-affording around tumors, which not only dramatically alleviated tumor hypoxia but also achieved a high-efficiency and repetitive PDT treatments. Furthermore, the innovative biological oxygen-affording engine described in the study presents a new class of oxygen-generating material for hypoxia-resistant cancer therapy.


Assuntos
Neoplasias/tratamento farmacológico , Oxigênio/metabolismo , Fotoquimioterapia , Porfirinas/administração & dosagem , Radiossensibilizantes/administração & dosagem , Hipóxia Tumoral , Animais , Linhagem Celular Tumoral , Chlorella/metabolismo , Clorofilídeos , Feminino , Luz , Camundongos Endogâmicos BALB C , Espécies Reativas de Oxigênio/metabolismo , Cicatrização
13.
Angew Chem Int Ed Engl ; 58(24): 8129-8133, 2019 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-30983107

RESUMO

In this work, a pincer-type complex [Cp*Ir-(SNPh)(SNHPh)(C2 B10 H9 )] (2) was synthesized and its reactivity studied in detail. Interestingly, molecular hydrogen can induce the transformation between the metalloradical [Cp*Ir-(SNPh)2 (C2 B10 H9 )] (5. ) and 2. A mixed-valence complex, [(Cp*Ir)2 -(SNPh)2 (C2 B10 H8 )] (7.+ ), was also synthesized by one-electron oxidation. Studies show that 7.+ is fully delocalized, possessing a four-centered-one-electron (S-Ir-Ir-S) bonding interaction. DFT calculations were also in good agreement with the experimental results.

14.
J Exp Clin Cancer Res ; 38(1): 165, 2019 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-30987652

RESUMO

BACKGROUND: miRNAs play crucial role in the progression of K-Ras-mutated nonsmall cell lung cancer (NSCLC). However, most studies have focused on miRNAs that target K-Ras. Here, we investigated miRNAs regulated by mutant K-Ras and their functions. METHODS: miRNAs regulated by mutant K-Ras were screened using miRNA arrays. miR-199b expression levels were measured by qRT-PCR. The protein expression levels were measured using Western blot and immunohistochemistry. The effects of miR-199b on NSCLC were examined both in vitro and in vivo by overexpressing or inhibiting miR-199b. DNA methylation was measured by bisulfite sequencing. RESULTS: An inverse correlation was observed between K-Ras mutation status and miR-199b levels in NSCLC specimens and cell lines. The inhibition of miR-199b stimulated NSCLC growth and metastasis, while restoration of miR-199b suppressed K-Ras mutation-driven lung tumorigenesis as well as K-Ras-mutated NSCLC growth and metastasis. miR-199b inactivated ERK and Akt pathways by targeting K-Ras, KSR2, PIK3R1, Akt1, and Rheb1. Furthermore, we determined that mutant K-Ras inhibits miR-199b expression by increasing miR-199b promoter methylation. CONCLUSION: Our findings suggest that mutant K-Ras plays an oncogenic role through downregulating miR-199b in NSCLC and that overexpression of miR-199b is a novel strategy for the treatment of K-Ras-mutated NSCLC.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , MicroRNAs/genética , Proteínas Proto-Oncogênicas p21(ras)/genética , Proteínas Proto-Oncogênicas p21(ras)/metabolismo , Carcinoma Pulmonar de Células não Pequenas/patologia , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Transformação Celular Neoplásica/genética , Transformação Celular Neoplásica/metabolismo , Metilação de DNA , Progressão da Doença , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Regulação Neoplásica da Expressão Gênica , Genes Reporter , Humanos , Neoplasias Pulmonares/patologia , Modelos Moleculares , Mutação , Proteínas Proto-Oncogênicas c-akt/metabolismo
15.
J Control Release ; 303: 253-262, 2019 06 10.
Artigo em Inglês | MEDLINE | ID: mdl-31028786

RESUMO

Cationic polymeric vectors attracted plenty of attentions in gene therapy due to nonimmunogenicity, easy to synthesis and flexible properties. However, biocompatibility challenge such as nonspecific interactions with blood cells and serum proteins, may affect the delivery efficiency of cationic vectors; besides, inefficient endosomal escape causes low transfection efficiency. Herein, we synthesized an anionic coating polymer dextran-g-aconic anhydride (Dex-Aco, DA) through a simple esterification reaction, which can protect cationic polymer poly(cystamine-bis-acrylamide)-agmatine-histamine (PCAH, PC) constructed nanomedicine against interactions with blood cells and serum proteins, improving biocompatibility. Interestingly, DA coating significantly increased the transfection efficiency of cationic PC,not due to the increase of cellular uptake, nor functioning as a receptor ligand, but was associated to the change of endocytosis pathway. Finally, using programmed cell death protein 4 (PDCD4) as a functional gene, DA coating PC NPs showed improved therapeutic effect and biocompatibility on tumor bearing mice. We believe that this DA coating PC NPs provides a facile method to improve the performance of cationic polymer vectors in gene therapy and has great potential for clinical applications.


Assuntos
Proteínas Reguladoras de Apoptose/genética , DNA/administração & dosagem , Vetores Genéticos , Neoplasias/terapia , Polímeros/administração & dosagem , Proteínas de Ligação a RNA/genética , Animais , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Feminino , Camundongos Endogâmicos BALB C , Transfecção
16.
J Control Release ; 294: 311-326, 2019 01 28.
Artigo em Inglês | MEDLINE | ID: mdl-30550939

RESUMO

Noncovalent forces are of considerable importance in the formation of self-assembled drug-delivery systems. In addition to non-destructively linking the delivery vehicle and guest drug, they provide multiple advantages, including protecting the structure of the drug, maintaining its functional effects, and facilitating its release. In particular, π-π stacking interactions have potential application in a comprehensive range of biomedical and biotechnological fields. Because they do not alter structural or functional properties of drugs, π-π stacking interactions have been used as a driving force in loading drugs into delivery systems, and in the design of self-assembling systems. Moreover, since the π-π stacking force is affected by environmental conditions such as pH, it has been used to design environment-responsive drug-delivery systems. In this review, we cover features of π-π stacking interactions and their applications to the design of drug-delivery systems. Carbon nanotubes, graphene-based nanomaterials, micelles and hydrogels-all delivery systems capable of π-π stacking interactions-are the focus. We also cover π-π stacking interaction-based loading of chemicals or biological drugs into delivery systems, and controlled release of drugs from delivery systems in certain environments. In addition, we examine the in vivo barriers for π-π stacking interaction-based drug delivery, and discuss challenges for clinical applications and future directions.


Assuntos
Sistemas de Liberação de Medicamentos , Animais , Química Farmacêutica , Humanos
17.
RSC Adv ; 9(21): 12110-12123, 2019 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-35548379

RESUMO

Multi-drug resistance (MDR) of tumor cells has greatly hindered the therapeutic efficacy of chemotherapeutic drugs, resulting in chemotherapy failure, while overexpression of ATP-binding cassette (ABC) transporters in cell membranes is the leading cause of MDR. In this study, we reported novel self-assembled triphenylphosphine-quercetin-polyethylene glycol-monoclonal antibody nanoparticles (TQ-PEG-mAb NPs) for overcoming MDR primarily through mitochondrial damage to block ATP supply to ABC transporters both in vitro and in vivo. The doxorubicin (DOX)-loaded NPs (TQ/DOX-PEG-mAb) were composed of two drugs (TQ and DOX) and an outer shielding shell of the PEG-mAb conjugate. Besides, the outer shell could be acid-responsively detached to expose the positive charge of TQ inside the NPs to enhance cellular uptake. TQ was proved to effectively induce mitochondrial damage with increased ROS levels and depolarization of mitochondrial membrane potential (MMP), leading to prominently reduced ATP supply to ABC transporters. Moreover, the involvement of the anti-vascular endothelial growth factor (VEGF) mAb was not only for efficient targeting but also for combined therapy. Consequently, TQ/DOX-PEG-mAb showed that the internalized amount of DOX was largely improved while the efflux amount was dramatically inhibited on MCF-7/ADR cells, indicating excellent reversal of DOX resistance. Importantly, the growth of DOX-resistant breast tumors was significantly inhibited with no evident systemic toxicity. Therefore, the employment of TQ-PEG-mAb is believed to be a new approach to improve the efficacy of chemotherapeutic drugs in MDR tumors.

18.
Chem Commun (Camb) ; 55(2): 210-213, 2018 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-30520909

RESUMO

Iridium(iii)-induced selective B(2,3)-H and C-H bond activations at mono- and bi-p-methoxybenzeneazo-substituted m-carboranes have been investigated. A powerful methodology is introduced for the preparation of unique polynuclear complexes featuring m-carboranyl ligands in a single step. The experimental results highlight that the base employed in the reaction plays a key role in the formation and the structures of the complexes.

19.
Dalton Trans ; 47(38): 13641-13646, 2018 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-30207352

RESUMO

A binuclear iridium complex, (Cp2*Ir2(CH2O)C2B10H8) (6), with a unique metal-metal bond has been synthesized and fully characterized. Importantly, this complex is constructed via selective C-H and B(3)-H bond activation on the carborane precursor. Additionally, when the proligand (2-pyridine)(o-carboranyl)methanol ligand was combined with a half-sandwich iridium complex, selective B(6)-H bond activation or metal-carbon bond formation can be induced by the use of different bases. And the rhodium complex constructed from (2-pyridine)(o-carboranyl)methanol ligand containing a metal-carbon bond has been obtained and fully characterized.

20.
Chem Commun (Camb) ; 54(59): 8218-8221, 2018 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-29985496

RESUMO

A highly hydrophilic polymer equipped with guanidinium groups was used to load aromatic ring-containing hydrophobic agent doxorubicin (DOX) via π-π interaction. The results have shown that the delivery system exhibited enhanced cellular uptake and antitumor efficiency compared with free drugs. This study opens new avenues for the application of hydrophilic polymers in drug delivery.


Assuntos
Antineoplásicos/farmacologia , Doxorrubicina/farmacologia , Portadores de Fármacos/química , Guanidinas/química , Polímeros/química , Animais , Antineoplásicos/química , Doxorrubicina/química , Portadores de Fármacos/síntese química , Liberação Controlada de Fármacos , Feminino , Fluorescência , Humanos , Interações Hidrofóbicas e Hidrofílicas , Células MCF-7 , Camundongos Endogâmicos BALB C , Polímeros/síntese química
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