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1.
Angew Chem Int Ed Engl ; : e202407427, 2024 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-38775385

RESUMO

By exploiting the electronic capabilities of the N-heterocyclic boryloxy (NHBO) ligand, we have synthesized "naked" acyclic gallyl [Ga{OB(NDippCH)2}2]- and indyl [In{OB(NDippCH)2}2]- anions (as their [K(2.2.2-crypt)]+ salts) through K+ abstraction from [KGa{OB(NDippCH)2}2] and [KIn{OB(NDippCH)2}2] using 2.2.2-crypt. These systems represent the first O-ligated gallyl/indyl systems, are ultimately accessed from cyclopentadienyl GaI/InI precursors by substitution chemistry, and display nucleophilic reactivity which is strongly influenced by the presence (or otherwise) of the K+ counterion.

2.
J Phys Condens Matter ; 33(16)2021 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-33401262

RESUMO

We present a systematic first-principles modelling study of the structural dynamics and thermal transport in CoSb3skutterudites with a series of noble-gas filler atoms. Filling with chemically-inert atoms provides an idealised model for isolating the effects of the fillers from the impact of redox changes to the host electronic structure. A range of analysis techniques are proposed to estimate the filler rattling frequencies, to quantify the separate impacts of the fillers on the phonon group velocities and lifetimes, and to show how changes to the phonon spectra and interaction strengths lead to suppressed lifetimes. The noble-gas fillers are found to reduce the thermal conductivity of the CoSb3framework by up to 15% primarily by suppressing the group velocities of low-lying optic modes. The filler rattling frequencies are determined by a detailed balance of increasing atomic mass and stronger interactions with the framework, and are found to be a good predictor of the impact on the heat transport. Lowering the rattling frequency below ∼1.5 THz by selecting heavy fillers that interact weakly with the framework is predicted to lead to a much larger suppression of the thermal transport, by inducing avoided crossings in the acoustic-mode dispersion and facilitating enhanced scattering and a consequent large reduction in phonon lifetimes. Approximate rattling frequencies determined from the harmonic force constants may therefore provide a useful metric for selecting filler atoms to optimise the thermal transport in skutterudites and other cage compounds such as clathrates.

3.
Cancer Med ; 7(12): 5928-5942, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30406970

RESUMO

BACKGROUND: Temozolomide (TMZ) is widely used to treat melanoma; however, response rates to TMZ are low because of rapid and frequent resistance. Conditionally, replicative adenoviruses (CRAds) are an effective and promising approach. The receptor for adenovirus is coxsackie-adenovirus receptor (CAR), which is poorly expressed in most cells. However, CD46, which is the receptor of species B adenoviruses (Ads), is highly expressed in many cells. METHODS: We constructed CRAd F5/35-ZD55-IL-24, which uses the viral receptors CAR and CD46 for entry into cells. We investigated the antitumor effect of F5/35-ZD55-IL-24 in combination with TMZ to treat melanoma in vitro and in vivo. RESULTS: The \results indicated that F5/35-ZD55-IL-24 in combination with TMZ produced additive or synergistic antitumor and pro-apoptotic effects in melanoma cells. The combination of F5/35-ZD55-IL-24 and TMZ significantly inhibited the growth of melanoma in vivo. In addition, the antitumor effect of F5/35-ZD55-IL-24 was superior to that of ZD55-IL-24 and ZD55-IL-24 combined with TMZ. CONCLUSIONS: The use of F5/35-ZD55-IL-24 in conjunction with TMZ is a promising approach for anti-melanoma therapy. Our results indicated that F5/35-ZD55-IL-24 in combination with TMZ produced additive or synergistic antitumor effect and pro-apoptotic effect in melanoma cells highly expressed CD46. The combination of F5/35-ZD55-IL-24 and TMZ significantly inhibited the growth of melanoma in vivo. We also found the antitumor effect of F5/35-ZD55-IL-24 was superior to ZD55-IL-24, the combination of F5/35-ZD55-IL-24 and TMZ had a more significant antitumor effect than ZD55-IL-24 combining with TMZ.


Assuntos
Adenoviridae/genética , Antineoplásicos Alquilantes/uso terapêutico , Interleucinas/genética , Melanoma/terapia , Temozolomida/uso terapêutico , Animais , Antineoplásicos Alquilantes/farmacologia , Linhagem Celular , Terapia Combinada , Proteína de Membrana Semelhante a Receptor de Coxsackie e Adenovirus , Terapia Genética , Vetores Genéticos , Humanos , Interleucinas/metabolismo , Masculino , Melanoma/metabolismo , Melanoma/patologia , Proteína Cofatora de Membrana , Camundongos Endogâmicos BALB C , Camundongos Nus , Temozolomida/farmacologia , Carga Tumoral
4.
Cancer Lett ; 423: 16-26, 2018 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-29524557

RESUMO

Chemotherapy is an important treatment for malignant tumors; however, its efficacy and clinical application are limited by its side effects and drug resistance properties. Chemotherapy and phototherapy exhibit synergistic anti-tumor effects. In the present study, a carboxylated poly(amido-amine) (PAMAM) with low cytotoxicity was synthesized as a delivery nanocarrier for loading chemotherapeutic drugs, temozolomide (TMZ), and fluorescent dye indocyanine green (ICG). Hyaluronic acid (HA), which targets the CD44-overexpressing cancer cells, was modified on the nanocarrier surface to enhance the selective killing of melanoma cells. Temperature effect and singlet oxygen production experiments showed that the ICG-loaded nanoparticles exhibited good capability to generate heat and singlet oxygen under near-infrared (NIR) light (808 nm) irradiation. In vivo imaging measurement confirmed that the ICG-encapsulated nanoparticle was delivered successfully and effectively accumulated in the tumor site. In vitro and in vivo experiments revealed that the joint application of TMZ- and ICG-loaded nanoparticle can kill melanoma cells and suppress growth after NIR light irradiation. Thus, HA-modified carboxylated PAMAM loaded with TMZ and ICG serves as a promising nanoplatform for melanoma treatment.


Assuntos
Receptores de Hialuronatos/metabolismo , Hipertermia Induzida/métodos , Melanoma/terapia , Poliaminas/química , Temozolomida/administração & dosagem , Animais , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Sistemas de Liberação de Medicamentos , Humanos , Verde de Indocianina , Melanoma/metabolismo , Camundongos , Nanopartículas , Temozolomida/química , Temozolomida/farmacologia , Ensaios Antitumorais Modelo de Xenoenxerto
5.
Cancer Biol Ther ; 18(11): 833-840, 2017 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-29144842

RESUMO

Significant progress has been made in the diagnosis and treatment of cancer; however, significant challenges remain. Conditionally replicating adenoviruses (CRAds), which not only kill cancer cells, but also serve as vectors to express therapeutic genes, are a novel and effective method to treat cancer. However, most adenoviruses are Ad5, which infect cells through the coxsackie and adenovirus receptor (CAR). The transduction efficacy of Ad5 is restricted because of the absent or low expression of CAR on several cancer cells. Ad serotype 35 has a different tropism pattern to Ad5. Ad35 attaches to cells via a non-CAR receptor, CD46, which is expressed widely on most tumor cells. Thus, chimeric adenoviral vectors consisting of the knob and shaft of Ad35 combined with Ad5 have been constructed. The chimeric fiber adenoviral vectors can transduce CAR-positive and CAR-negative cell lines. In this review, we explore the application of the novel fiber chimeric conditionally replicative adenovirus-Ad5/F35 in tumor therapy in terms of safety, mechanism, transduction efficacy, and antitumor effect.


Assuntos
Adenoviridae/genética , Neoplasias/terapia , Quimerismo , Terapia Genética , Humanos , Neoplasias/genética
6.
PLoS One ; 12(5): e0175136, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28472042

RESUMO

OBJECTIVE: Many studies have previously investigated the potential association between mobile phone use and the risk of glioma. However, results from these individual studies are inconclusive and controversial. The objective of our study was to investigate the potential association between mobile phone use and subsequent glioma risk using meta-analysis. METHODS: We performed a systematic search of the Science Citation Index Embase and PubMed databases for studies reporting relevant data on mobile phone use and glioma in 1980-2016. The data were extracted and measured in terms of the odds ratio (OR) and 95% confidence interval (CI) using the random effects model. Subgroup analyses were also carried out. This meta-analysis eventually included 11 studies comprising a total 6028 cases and 11488 controls. RESULTS: There was a significant positive association between long-term mobile phone use (minimum, 10 years) and glioma (OR = 1.44, 95% CI = 1.08-1.91). And there was a significant positive association between long-term ipsilateral mobile phone use and the risk of glioma (OR = 1.46, 95% CI = 1.12-1.92). Long-term mobile phone use was associated with 2.22 times greater odds of low-grade glioma occurrence (OR = 2.22, 95% CI = 1.69-2.92). Mobile phone use of any duration was not associated with the odds of high-grade glioma (OR = 0.81, 95% CI = 0.72-0.92). Contralateral mobile phone use was not associated with glioma regardless of the duration of use. Similarly, this association was not observed when the analysis was limited to high-grade glioma. CONCLUSIONS: Our results suggest that long-term mobile phone use may be associated with an increased risk of glioma. There was also an association between mobile phone use and low-grade glioma in the regular use or long-term use subgroups. However, current evidence is of poor quality and limited quantity. It is therefore necessary to conduct large sample, high quality research or better characterization of any potential association between long-term ipsilateral mobile phone use and glioma risk.


Assuntos
Neoplasias Encefálicas/etiologia , Telefone Celular , Glioma/etiologia , Humanos , Fatores de Risco
7.
Int J Cancer ; 141(4): 646-653, 2017 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-28340496

RESUMO

Melanoma is a most aggressive skin cancer with limited therapeutic options and its incidence is increasing rapidly in recent years. The discovery and application of new targeted therapy agents have shown significant benefits. However, adverse side-effects and resistance to chemotherapy remain formidable challenges in the clinical treatment of malignant melanoma. Nanotherapeutics offers an important prospect of overcoming these drawbacks. The anti-tumoral applications of nanomedicine are varied, including those in chemotherapy, RNA interference, photothermal therapy, and photodynamic therapy. Furthermore, nanomedicine allows delivery of the effector structures into the tumor site via passive or active targeting, thereby allowing increased therapeutic specificity and reduced side effects. In this review, we summarize the latest developments in the application of nanocarrier-mediated targeted drug delivery to melanoma and nanomedicine-related clinical trials in melanoma treatment. We also discuss existing problems and opportunities for future developments, providing direction and new thoughts for further studies.


Assuntos
Antineoplásicos/administração & dosagem , Melanoma/tratamento farmacológico , Nanopartículas/administração & dosagem , Neoplasias Cutâneas/tratamento farmacológico , Animais , Antineoplásicos/uso terapêutico , Portadores de Fármacos , Humanos , Nanopartículas/uso terapêutico , Fotoquimioterapia , Melanoma Maligno Cutâneo
8.
Cancer Lett ; 390: 168-175, 2017 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-28040545

RESUMO

Theranostics based on nanoparticles have developed rapidly in the past decade and have been widely used in the diagnosis and treatment of liver cancer, breast cancer, and other tumors. However, for skin cancers, there are limited studies. In the present study, we successfully synthesized a theranostic nanoparticle by grating IR820 onto the surface of chitosan-coated magnetic iron oxide, IR820-CS-Fe3O4, showing an excellent magnetic resonance imaging (MRI) capability and cytotoxic effects against melanoma under irradiation with a near-infrared (NIR) laser (808 nm) in vitro. Furthermore, good stability for up to 8 days and negligible cytotoxicity were observed. These characteristics are important for biomedical applications of nanoparticles. In conclusion, we provide a novel and potential theranostic platform for melanoma treatment and detection.


Assuntos
Raios Infravermelhos , Nanopartículas de Magnetita/química , Nanopartículas de Magnetita/uso terapêutico , Melanoma/terapia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos da radiação , Meios de Contraste/química , Citometria de Fluxo , Temperatura Alta , Humanos , Verde de Indocianina/análogos & derivados , Verde de Indocianina/química , Microscopia Eletrônica de Transmissão
9.
Oncol Rep ; 37(2): 995-1001, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28035395

RESUMO

The present study was carried out to prepare and evaluate a temozolomide (TMZ)-loaded polyamide-amine dendrimer (PAMAM)­based nanodrug delivery system, and to explore its ability to target human melanoma (A375) cells in vitro. Firstly, PAMAM-PEG and PAMAM-PEG-GE11 were synthesized by substitution and addition reactions, and their products were identified and characterized by fourier transform-infrared (FTIR), proton nuclear magnetic resonance (1H-NMR) and transmission electron microscopy (TEM), as well as differential light scattering (DLS). Using fluorescein isothiocyanate (FITC)-modified PAMAM, we synthesized FITC-PAMAM, FITC-PAMAM-PEG and FITC-PAMAM-PEG-GE11. Fluorescence microscopy and flow cytometry were used to monitor the uptake of A375 cells of these three nanomaterials. Secondly, TMZ-PAMAM­PEG­GE11-HA drug complexes were prepared by ultrasonic emulsification, and their particle size, zeta potential and morphology were evaluated by DLS and TEM. Drug loading (DL) and encapsulation efficiency (EE) were assayed by ultraviolet spectrophotometry. Thirdly, we ascertained whether TMZ-PAMAM-PEG-GE11-HA conjugates could target A375 cells in vitro. The TMZ-PAMAM­PEG­GE11-HA nanodrug delivery system was successfully synthesized according to FTIR and 1H-NMR. Its mean particle size was 183.2 nm and zeta potential was -0.01 mV. It was a regular sphere with good uniformity. The EE of TMZ-PAMAM-PEG-GE11-HA was ~50.63% and DL ~10.4%. TMZ-PAMAM-PEG-GE11-HA targeted A375 cells in vitro. In conclusion, the TMZ-PAMAM­PEG-GE11-HA nanodrug delivery system was successfully prepared, and demonstrated its potential for targeting A375 cells in vitro. This system enhanced the sensitivity of A375 cells to TMZ, and provided a novel targeted strategy for the treatment of metastatic melanoma.


Assuntos
Dacarbazina/análogos & derivados , Sistemas de Liberação de Medicamentos/métodos , Melanoma/tratamento farmacológico , Nanopartículas/administração & dosagem , Nanopartículas/química , Antineoplásicos Alquilantes/administração & dosagem , Antineoplásicos Alquilantes/química , Linhagem Celular Tumoral , Dacarbazina/administração & dosagem , Dacarbazina/química , Dendrímeros/administração & dosagem , Dendrímeros/química , Fluoresceína-5-Isotiocianato/química , Humanos , Espectroscopia de Ressonância Magnética , Melanoma/patologia , Microscopia Eletrônica de Transmissão , Peptídeos/química , Espectroscopia de Infravermelho com Transformada de Fourier , Temozolomida
10.
Cancer Lett ; 379(1): 24-31, 2016 08 28.
Artigo em Inglês | MEDLINE | ID: mdl-27235607

RESUMO

Despite significant improvements in diagnostic methods and innovations in therapies for specific cancers, effective treatments for neoplastic diseases still represent major challenges. Nanotechnology as an emerging technology has been widely used in many fields and also provides a new opportunity for the targeted delivery of cancer drugs. Nanoscale delivery of chemotherapy drugs to the tumor site is highly desirable. Recent studies have shown that nanoscale drug delivery systems not only have the ability to destroy cancer cells but may also be carriers for chemotherapy drugs. Some studies have demonstrated that delivery of chemotherapy via nanoscale carriers has greater therapeutic benefit than either treatment modality alone. In this review, novel approaches to nanoscale delivery of chemotherapy are described and recent progress in this field is discussed.


Assuntos
Antineoplásicos/administração & dosagem , Portadores de Fármacos , Sistemas de Liberação de Medicamentos/métodos , Nanomedicina/métodos , Nanopartículas , Neoplasias/tratamento farmacológico , Tecnologia Farmacêutica/métodos , Animais , Antineoplásicos/química , Antineoplásicos/metabolismo , Composição de Medicamentos , Humanos , Neoplasias/metabolismo , Neoplasias/patologia
11.
Medicine (Baltimore) ; 95(16): e3406, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27100429

RESUMO

The aim of this study was to compare the efficacy and safety of interferon (IFN) combined with dacarbazine (DTIC) (experimental group) versus DTIC alone (control group) in cutaneous malignant melanoma. After searching all available databases, eligible articles were identified and subjected to quality assessment. Meta-analysis was performed using RevMan 5.3; combined relative risk (RR) and 95% confidence intervals (95% CIs) were calculated for survival rates, response rates, and adverse events. Eight randomized controlled trials published between 1990 and 2014 involving 795 patients were included in the meta-analysis. Compared with DTIC alone, IFN combined with DTIC significantly increased the overall response rate (RR = 1.59, 95% CI 1.21-2.08, P = 0.0008),the complete response rate (RR = 3.30, 95% CI 1.89-5.76, P < 0.0001), 2-year survival (RR = 1.59, 95% CI 0.99-2.54, P = 0.050) grade ≥3 hematologic toxicity (RR = 2.30, 95% CI 1.32-4.02, P = 0.003), neurotoxicity (RR = 18.15, 95% CI 5.34-61.74, P < 0.00001), and flu-like symptoms (RR = 6.31, 95% CI 1.95-20.39, P = 0.002). The partial response rate, grade ≥3 nausea and vomiting, treatment-related, and 1- and 3-year survival were not significantly different between IFN combined with DTIC and DTIC alone. IFN combined with DTIC may moderately improve the complete response rate, but increases the incidence of adverse events and has no significant effect on 1- and 3-year survival in cutaneous malignant melanoma.


Assuntos
Dacarbazina/uso terapêutico , Interferon-alfa/uso terapêutico , Melanoma/tratamento farmacológico , Antineoplásicos Alquilantes/uso terapêutico , Humanos , Fatores Imunológicos/uso terapêutico , Indução de Remissão , Neoplasias Cutâneas , Resultado do Tratamento , Melanoma Maligno Cutâneo
12.
Artigo em Inglês | MEDLINE | ID: mdl-26955964

RESUMO

Hepatocellular carcinoma (HCC) is one of the most common malignant tumors worldwide. However, the inherent limitations of traditional surgery and insensitivity to radiation and chemotherapy result in failing treatment and poor prognosis. In recent years, the development and advances of nanotechnology has brought new hope for the diagnosis and treatment of HCC. This article reviews the development of nanoparticles used for cancer detection, diagnosis and treatment due to their large specific surface area and unique optical, electronic and magnetic properties. Moreover, studies have shown that after intended surface modification, nano-carriers can achieve active targeting effect, which improves the efficiency of chemotherapeutic drugs and decreases their side effects. In this review, we provide an overview of these studies results, patents about novel nanomaterials and conclude with a discussion about future development.


Assuntos
Antineoplásicos/administração & dosagem , Carcinoma Hepatocelular/diagnóstico , Carcinoma Hepatocelular/terapia , Sistemas de Liberação de Medicamentos/métodos , Terapia Genética/métodos , Neoplasias Hepáticas/diagnóstico , Neoplasias Hepáticas/terapia , Técnicas de Diagnóstico Molecular , Nanomedicina/métodos , Nanopartículas , Animais , Carcinoma Hepatocelular/genética , Meios de Contraste , Difusão de Inovações , Portadores de Fármacos , Humanos , Neoplasias Hepáticas/genética , Valor Preditivo dos Testes , Resultado do Tratamento
13.
J Coll Physicians Surg Pak ; 25(9): 680-8, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26374366

RESUMO

Melanoma is one of the most malignant forms of skin cancer; with a rapidly increasing prevalence. Early-stage melanoma is curable, but advanced metastatic melanoma is almost always fatal, and patients with such advanced disease have short median survival. Surgery and radiotherapy play a limited role in the treatment of metastatic melanoma. Rather, chemotherapy remains the mainstay of treatment, although other approaches, including biotherapy and gene therapy, have been attempted. The authors hereby, evaluated the use of temozolomide (TMZ) for treating metastatic melanoma compared to dacarbazine (DTIC), the effectiveness of TMZ for treating brain metastases, as well as TMZ resistance and how the efficacy of TMZ in malignant melanoma can be increased. Two chemotherapeutic regimens are commonly used for palliative treatment of malignant melanoma: intravenous administration of DTIC and oral administration of the alkylating agent temozolomide (TMZ). Compared to DTIC, TMZ is very well tolerated and has an advantage in terms of improving the quality of life of patients with metastatic melanoma. While the prognosis is currently unpromising, chemotherapy plays a palliative role for patients with metastatic melanoma. The toxicity of treatment regimens based on DTIC and TMZ do not differ significantly, although TMZ is costlier. These findings provide a reference for future researchers via a comprehensive analysis of the relevant literature.


Assuntos
Antineoplásicos Alquilantes/uso terapêutico , Neoplasias Encefálicas/secundário , Dacarbazina/análogos & derivados , Melanoma/tratamento farmacológico , Neoplasias Cutâneas/patologia , Neoplasias Encefálicas/tratamento farmacológico , Dacarbazina/uso terapêutico , Humanos , Melanoma/patologia , Melanoma/psicologia , Qualidade de Vida , Temozolomida , Resultado do Tratamento , Melanoma Maligno Cutâneo
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