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1.
Artigo em Inglês | MEDLINE | ID: mdl-32242313

RESUMO

Pentamidine sensitizes FDA-approved antibiotics to combat Gram-negative pathogens. We screened 1374 FDA-approved non-antibiotics for their ability to be sensitized by pentamidine against Escherichia coli. We identified mitomycin C and mefloquine as potent hits effective against multiple drug-resistant, Gram-negative bacteria. Killing kinetics and an in vivo model with Caenorhabditis elegans (C. elegans) revealed that such combinations produced synergy against colistin-resistant Enterobacter cloacae (E. cloacae). These findings suggest combinations of FDA-approved non-antibiotics, and pentamidine can be repurposed into new antimicrobial agents.

2.
Drug Des Devel Ther ; 14: 1333-1339, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32308366

RESUMO

Background: Carbon monoxide (CO) poisoning is a common health problem among people in many countries, primarily because of its severe clinical effects and high toxicological morbidity and mortality. Acute brain injury and delayed encephalopathy after acute carbon monoxide poisoning (DEACMP) are the most common neurological complications. This study was performed to assess the efficacy of N-butylphthalide (NBP) and dexamethasone (DXM) combined with hyperbaric oxygen (HBO) in patients with DEACMP. Patients and Methods: A total of 171 patients with DEACMP were recruited and assigned to the combined therapy group (receiving NBP and DXM 5 mg/day plus HBO therapy) or the control group (HBO therapy as monotherapy). Conventional treatments were provided for all patients. The cognition and movement changes in patients were evaluated by the Mini-Mental State Examination (MMSE), the Montreal Cognitive Assessment (MoCA) scale and the Barthel index of activities of daily living (ADL) before and after the treatment at 1 month, 3 months, and 1 year, respectively. Results: At 1 month, 3 months, and 1 year after the treatment, the MMSE, MoCA and ADL scores were all significantly higher in the combined therapy group than those in the control group. There were no significant alterations in blood glucose, blood lipids, or liver and kidney function during the whole treatment session. Some patients experienced loss of appetite, mild headache and minor skin irritations. However, these patients recovered by themselves and needed no additional medications or special treatment. Conclusion: These results indicated that NBP and DXM combined with HBO for the treatment of DEACMP can significantly improve the cognitive and motor functions of patients and is very safe.

3.
Front Chem ; 7: 595, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31552217

RESUMO

Binary metal oxides composed of molybdenum-vanadium oxides are promising candidates for supercapacitors. Here, we report the synthesis of one-dimensional V0.13Mo0.87O2.935 nanowires through a facile one-step hydrothermal method. This nanowire presented a high specific capacitance of 394.6 F g-1 (1 mV s-1) as an electrode applied to the supercapacitor. Importantly, this electrode showed a perfect rate capability of 91.5% (2 to 10 A g-1) and a continuous verified outstanding cyclic voltammetry of 97.6% after 10,000 cycles. These superior electrochemical properties make the synthesized V0.13Mo0.87O2.935 nanowires a prospective candidate for high-performance supercapacitors.

4.
J Colloid Interface Sci ; 556: 386-391, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31470353

RESUMO

The design of multicomponent electrode materials is attractive for advanced supercapacitors due to synergistic and multifunctional effects among different active materials. We reported here a structure-designed synthesis strategy to controllably fabricate hierarchical NiCo2O4@NiO composites on carbon fiber paper. The hierarchical structure with NiCo2O4 core and NiO shell provided more active sites for ion transportation and storage to improve utilization rate of electrode materials, enhancing the specific capacitance and rate performance. As an ideal electrode material for supercapacitors, the NiCo2O4@NiO electrode exhibit high specific capacitance (1188 F/g at 2 A/g), excellent rate capability with ∼85% capacitance retained at 10 A/g, and compelling cycling performance (∼106.8% of the initial capacitance retention over 7000 cycles). The present work demonstrated a structure-designed strategy to construct high-performance multicomponent electrode materials for supercapacitors.

5.
Materials (Basel) ; 12(16)2019 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-31426615

RESUMO

TiO2 is regarded as a prospective electrode material owing to its excellent electrochemical properties such as the excellent cycling stability and the high safety. However, its low capacity and low electronic conductivity greatly restrict the further improvement in electrochemical performance. A new strategy was put forward to solve the above defects involved in TiO2 in which the low capacity was enhanced by nanomerization and porosity of TiO2, and the low electronic conductivity was improved by introducing Ag with a high conductivity. One-dimensional mesoporous Ag nanoparticles-embedded TiO2 nanofibers (Ag@TiO2 nanofibers) were successfully synthesized via a one-step electrospinning process combined with subsequent annealing treatment in this study. The microstructure and morphology of mesoporous TiO2@Ag nanofibers were confirmed by X-ray diffraction, scanning electron microscopy, transmission electron microscopy, and nitrogen adsorption-desorption. TiO2 nanofibers mainly consisted of a large amount of anatase TiO2, accompanied with traces of rutile TiO2. Ag nanoparticles were uniformly distributed throughout TiO2 nanofibers and promoted the transformation of TiO2 from the anatase to the rutile. The corresponding electrochemical performances are measured by galvanostatic charge-discharge, cycle stability, rate performance, cycle voltammetry, and electrochemical impedance spectroscopy measurements in this research, with pristine TiO2 nanofibers as the reference. The results indicated that the introduction of Ag nanoparticles into TiO2 nanofibers significantly improved the diffusion coefficient of Li ions (5.42 × 10-9 cm2⋅s-1 for pristine TiO2, 1.96 × 10-8 cm2⋅s-1 for Ag@TiO2), and the electronic conductivity of TiO2 (1.69 × 10-5 S⋅cm-1 for pristine TiO2, and 1.99 × 10-5 S⋅cm-1 for Ag@TiO2), based on which the comprehensive electrochemical performance were greatly enhanced. The coulombic efficiency of the Ag@TiO2 nanofibers electrode at the first three cycles was about 56%, 93%, and 96%, which was higher than that without Ag (48%, 66%, and 79%). The Ag@TiO2 nanofibers electrode exhibited a higher specific discharge capacity of about 128.23 mAh⋅g-1 when compared with that without Ag (72.76 mAh·g-1) after 100 cycles at 100 mA·g-1. With the current density sharply increased from 40 mA·g-1 to 1000 mA·g-1, the higher average discharge capacity of 56.35 mAh·g-1 was remained in the electrode with Ag, when compared with the electrode without Ag (average discharge capacity of about 12.14 mAh·g-1). When the current density was returned to 40 mA·g-1, 80.36% of the initial value was returned (about 162.25 mAh·g-1) in the electrode with Ag, which was evidently superior to that without Ag (about 86.50 mAh·g-1, only 55.42% of the initial value). One-dimensional mesoporous Ag@TiO2 nanofibers can be regarded as a potential and promising candidate as anode materials for lithium ion batteries.

6.
Chem Commun (Camb) ; 55(64): 9432-9435, 2019 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-31328209

RESUMO

Humid atmospheric pressure plasma jets (APPJs) sustained in an argon/water vapour mixture were adopted to treat CoMoO4 nanosheets arrays, which resulted in micro-defects on the surface and the appearance of hydroxyl (OH-) groups absorbed on the nanosheets. Benefiting from these changes, the plasma treated CoMoO4 exhibited similar catalytic property to RuO2, an overpotential 70 mV lower than for pristine CoMoO4 and maintained good stability after 30 hours for the water oxidation.

7.
Medicine (Baltimore) ; 98(7): e14445, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30762755

RESUMO

The aim of this study was to investigate the association between purinergic receptor P2X7 (P2RX7) gene rs1718125 polymorphism and analgesic effect of fentanyl after surgery among patients with lung cancer in a Chinese Han population.A total of 238 patients with lung cancer who received resection were enrolled in our study. The genotype distributions of P2RX7 rs1718125 polymorphism were detected by polymerase chain reaction and direct sequencing. Postoperative analgesia was performed by patient-controlled intravenous analgesia, and the consumption of fentanyl was recorded. The postoperative pain was measured by visual analog scale (VAS). Differences in postoperative VAS score and postoperative fentanyl consumption for analgesia in different genotype groups were analyzed by analysis of variance assay.The frequencies of GG, GA, and AA genotypes were 46.22%, 44.96%, and 8.82%, respectively. After surgery, the postoperative VAS score of GA group was significantly high in the period of analepsia after general anesthesia and at 6 hours after surgery (P = .041 and P = .030, respectively), while AA group exhibited obviously high in the period of analepsia after general anesthesia (P < .001), at postoperative 6 hours (P = .006) and 24 hours (P = .016). Moreover, the patients carrying GA and AA genotypes needed more fentanyl to control pain within 48 hours after surgery (P < .05 for all).P2RX7 gene rs1718125 polymorphism is significantly associated with postoperative pain and fentanyl consumption in patients with lung cancer.


Assuntos
Analgésicos Opioides/uso terapêutico , Fentanila/uso terapêutico , Neoplasias Pulmonares/genética , Dor Pós-Operatória/genética , Receptores Purinérgicos P2X7/genética , Idoso , Analgesia Controlada pelo Paciente/estatística & dados numéricos , Grupo com Ancestrais do Continente Asiático/genética , China , Feminino , Genótipo , Humanos , Neoplasias Pulmonares/cirurgia , Masculino , Pessoa de Meia-Idade , Medição da Dor , Dor Pós-Operatória/tratamento farmacológico , Polimorfismo de Nucleotídeo Único/genética , Fatores de Tempo
8.
Nanomaterials (Basel) ; 9(1)2019 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-30669389

RESUMO

The harmful nature of high concentrations of antibiotics to humans and animals requires the urgent development of novel materials and techniques for their absorption. In this work, CTAB (Cetyltrimethyl Ammonium Bromide)-assisted synthesis of ZIF-8 (zeolitic imidazolate framework)-derived hollow carbon (ZHC) was designed, prepared, and used as a high-performance adsorbent, and further evaluated by Langmuir and Freundlich isothermal adsorption experiments, dynamic analysis, as well as theoretical calculation. The maximum capacities of ZHC for adsorbing tetracycline (TC), norfloxacin (NFO), and levofloxacin (OFO) are 267.3, 125.6, and 227.8 mg g-1, respectively, which delivers superior adsorptive performance when compared to widely studied inorganic adsorbates. The design concept of ZIF-8-derived hollow carbon material provides guidance and insights for the efficient adsorbent of environmental antibiotics.

9.
J Nanosci Nanotechnol ; 19(1): 263-267, 2019 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-30327034

RESUMO

The new demands for energy storage systems have been placed with demands for flexible wearable electronics. Herein, rugby-like GeO2 nanoparticles (NPs) have been directly grown on carbon cloth (GeO2 NPs/CC) through a one-step hydrolysis process at room temperature, which can be used as a self-supporting flexible anode for lithium ion battery (LIBs). The rugby-like GeO2 NPs/CC showed an improved lithium-storage performance with features of high reversible capacity ~2000 mA·h·g-1 even after 100 cycles and good cycling stability. Besides, its initial coulomb efficiency (79.1%) was also enhanced compared to that of some reported GeO2-based materials.

10.
Trials ; 19(1): 348, 2018 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-29970155

RESUMO

BACKGROUND: Primary dysmenorrhea (PD), is one of main gynecological complaints in women of child-bearing age. Common medications for PD do not always achieve satisfactory outcome of pain relief. Hence, both health professionals and patients are seeking help from complementary and alternative medicine. The acupoint herbal plaster (AHP), which appears to be a safe and effective way to alleviate menstrual pain, as well as to improve other PD-related symptoms. Despite similar clinical studies for this condition in the past, no high-quality methodology-based clinical trial has been reported to date. The current study aims to assess the efficacy of the AHP compared with the acupoint placebo plaster (APP) and being placed on a waiting-list control group in patients with primary dysmenorrhea. METHODS/DESIGN: This study is a randomized, single-center, placebo-controlled clinical trial. A total of 180 women with PD will be included and randomly allocated to the AHP, APP and waiting-list (WL) groups in a 1:1:1 ratio. Patients in the AHP group will be provided with herbal plasters (Shaofuzhuyu decoction) on various acupoints: Shenque (CV8), Guanyuan (CV4), Qihai (CV5), Ciliao (BL32) and Zigong (EX-CA1). Women in the APP group will receive placebo plasters on the same acupoints, and no intervention will be given to the WL group until completion of the study. The primary outcome will be pain intensity reduction measured by a Visual Analog Scale (VAS), with other outcome measurements including the Cox Menstrual Symptom Scale (CMSS), the 12-Item Short Form Health Survey (SF-12) and the Participant Global Impression of Change (PGIC). All assessments will be performed at baseline, each menstrual cycle during the treatment course and the follow-up course. Any adverse events will be recorded throughout the study. DISCUSSION: This is the first study to compare the changes in menstrual pain after three different interventions: the active intervention (AHP), the placebo intervention (APP), and a period of no intervention (WL). This three-arm randomized controlled trial (RCT) aims to investigate the relative contributions of the specific (AHP vs. APP) and non-specific (APP vs. WL) effects to the overall clinical effects of the active AHP on women with PDM. The scientific and rigorous methodology design of this trial should gather good evidence to assess the curative effects and safety of the AHP on PD. Moreover, the results of this study may provide evidence-based references for the treatment of menstrual pain in future. TRIAL REGISTRATION: Chinese Clinical Trial Registry, ID: ChiCTR-TRC-16008701. Registered on 22 July 2016.


Assuntos
Pontos de Acupuntura , Bandagens , Medicamentos de Ervas Chinesas/administração & dosagem , Dismenorreia/terapia , Administração Cutânea , Adolescente , Adulto , China , Medicamentos de Ervas Chinesas/efeitos adversos , Dismenorreia/diagnóstico , Dismenorreia/fisiopatologia , Feminino , Humanos , Medição da Dor , Ensaios Clínicos Controlados Aleatórios como Assunto , Fatores de Tempo , Resultado do Tratamento , Adulto Jovem
11.
Zhen Ci Yan Jiu ; 43(4): 269-73, 2018 Apr 25.
Artigo em Chinês | MEDLINE | ID: mdl-29888584

RESUMO

OBJECTIVE: To analyze studies published in journals included in PubMed in terms of randomized controlled trials (RCTs) examining the therapeutic effect of acupuncture for simple obesity, so as to provide a reference for subsequent RCT-related designs and results. METHODS: RCT literature about acupuncture treatment of simple obesity from the PubMed database and from 2000 to 2016 was retrieved by using keywords of "obesity" "fat" "acupuncture" "joint application of acupuncture and herbal medicine" or "auricular point" "electroacupuncture", "acupoint application", or "cupping", followed by screening, extraction and evaluation of the design methodology and outcomes using Consolidated Standards for Reporting of Trials (CONSORT) and Standards for Reporting Interventions in Controlled Trials of Acupuncture (STRICTA). RESULTS: Fourteen articles from six countries in Asia examining the therapeutic effect of acupuncture in the treatment of simple obesity mainly by using acupoints of the Stomach Meridian were included. Generally, acupuncture was found to be more effective than sham acupuncture. However, PubMed did not include any RCTs comparing acupuncture with western medicine for weight loss and many problems (as details of needling manipulation, etc.) remained in the the research reports available in the database. CONCLUSION: All the existing RCTs generally affirm the positive efficacy of acupuncture for simple obesity, but high-quality RCTs, particularly those comparing acupuncture with western medicines for weight loss are lacking.


Assuntos
Terapia por Acupuntura , Humanos , Obesidade/terapia , PubMed , Ensaios Clínicos Controlados Aleatórios como Assunto
12.
J Int Med Res ; 46(4): 1404-1413, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29458276

RESUMO

Objective Postoperative cognitive dysfunction (POCD) is common after surgery in elderly patients and is associated with high morbidity. The molecular mechanisms responsible for POCD are unknown. Minocycline, an inhibitor of microglial activation, may be useful in treating and preventing POCD. We explored whether minocycline can inhibit microglial activation and prevent POCD in aged rats as a surgery model. Methods Rats aged 18 to 20 months were randomly allocated to the following groups: naïve, abdominal surgery alone, or minocycline injection before abdominal surgery. Hippocampal cytokine mRNA levels were measured at 3 hours, 1 day, 3 days, and 7 days after surgery, and microglial activation was measured at 3 hours and 7 days after surgery. Memory was assessed using the Morris water maze test. Results Surgery resulted in severe cognitive impairment in aged rats and induced a significant neuroinflammatory response and microglial activation. The use of minocycline can prevent microglial activation after surgery, but delayed microglial activation may occur. The use of minocycline may further impair memory after surgery. Conclusion Minocycline can restrain microglial activation and restrict the inflammatory response in the hippocampus early after surgery, but it may induce delayed microglial activation and cannot prevent POCD in aged rats.


Assuntos
Envelhecimento/patologia , Disfunção Cognitiva/etiologia , Disfunção Cognitiva/prevenção & controle , Microglia/patologia , Minociclina/efeitos adversos , Complicações Pós-Operatórias/prevenção & controle , Animais , Disfunção Cognitiva/fisiopatologia , Relação Dose-Resposta a Droga , Hipocampo/metabolismo , Hipocampo/patologia , Hipocampo/fisiopatologia , Interleucina-1beta/genética , Interleucina-1beta/metabolismo , Memória de Curto Prazo , Microglia/metabolismo , Complicações Pós-Operatórias/fisiopatologia , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ratos Sprague-Dawley , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/metabolismo
13.
Oncol Res ; 26(6): 827-835, 2018 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-28477403

RESUMO

Pancreatic ductal adenocarcinoma (PDAC) is one of the leading causes of cancer deaths due to its highly aggressive biological nature and resistance to chemotherapy. Previous studies indicate that miR-21 is an important regulator in the activation of cancer-associated fibroblasts (CAFs). However, whether miR-21 in CAFs would regulate PDAC's tumor microenvironment and lead to drug resistance remain unknown. In this study, we evaluated the relationship between CAF activation, miR-21 expression, and drug resistance using tumor samples from PDAC patients. We changed the miR-21 expression level in CAFs and tested its roles in regulating the function of CAFs. In addition, we explored the roles of miR-21 in CAFs in the development of PDAC using an animal model. We found that PDAC patients who were resistant to gemcitabine treatment tended to have higher miR-21 expression and more activated CAFs. An in vitro study showed that CAFs with high miR-21 expression had elevated MMP-3, MMP-9, PDGF, and CCL-7 expression and promoted the invasion of PDAC cell lines. miR-21 overexpression also contributed to the activation of CAFs by regulating the PDCD4 gene. The in vivo study showed that upregulating miR-21 in CAFs promoted PDAC desmoplasia and increased its drug resistance to gemcitabine treatment, but downregulating miR-21 in CAFs suppressed desmoplasia and enhanced the effect of gemcitabine. We concluded that miR-21 promoted the activation of CAFs and contributed to the drug resistance of PDAC.


Assuntos
Proteínas Reguladoras de Apoptose/metabolismo , Fibroblastos Associados a Câncer/patologia , Carcinoma Ductal Pancreático/patologia , Desoxicitidina/análogos & derivados , Resistencia a Medicamentos Antineoplásicos/genética , MicroRNAs/genética , Neoplasias Pancreáticas/patologia , Proteínas de Ligação a RNA/metabolismo , Animais , Antimetabólitos Antineoplásicos/farmacologia , Apoptose , Proteínas Reguladoras de Apoptose/genética , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Fibroblastos Associados a Câncer/efeitos dos fármacos , Fibroblastos Associados a Câncer/metabolismo , Carcinoma Ductal Pancreático/tratamento farmacológico , Carcinoma Ductal Pancreático/genética , Movimento Celular , Proliferação de Células , Desoxicitidina/farmacologia , Feminino , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Neoplasias Pancreáticas/tratamento farmacológico , Neoplasias Pancreáticas/genética , Prognóstico , Proteínas de Ligação a RNA/genética , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto
15.
World J Gastroenterol ; 23(21): 3907-3914, 2017 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-28638231

RESUMO

AIM: To detect the expression of pleiotrophin (PTN) and N-syndecan in pancreatic cancer and analyze their association with tumor progression and perineural invasion (PNI). METHODS: An orthotopic mouse model of pancreatic cancer was created by injecting tumor cells subcapsularly in a root region of the pancreas beneath the spleen. Pancreatic cancer tissues were taken from 36 mice that survived for more than 90 d. PTN and N-syndecan proteins were detected by immunohistochemistry and analyzed for their correlation with pathological features, PNI, and prognosis. RESULTS: The expression rates of PTN and N-syndecan proteins were 66.7% and 61.1%, respectively, in cancer tissue. PTN and N-syndecan expression was associated with PNI (P = 0.019 and P = 0.032, respectively). High PTN expression was closely associated with large bloody ascites (P = 0.009), liver metastasis (P = 0.035), and decreased survival time (P = 0.022). N-syndecan expression was significantly associated with tumor size (P = 0.025), but not with survival time (P = 0.539). CONCLUSION: High PTN and N-syndecan expression was closely associated with metastasis and poor prognosis, suggesting that they may promote tumor progression and PNI in the orthotopic mouse model of pancreatic cancer.


Assuntos
Biomarcadores Tumorais/metabolismo , Proteínas de Transporte/metabolismo , Citocinas/metabolismo , Neoplasias Pancreáticas/patologia , Nervos Periféricos/patologia , Sindecana-3/metabolismo , Animais , Linhagem Celular Tumoral , Progressão da Doença , Humanos , Imuno-Histoquímica , Estimativa de Kaplan-Meier , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Invasividade Neoplásica/patologia , Pâncreas/patologia , Neoplasias Pancreáticas/mortalidade , Prognóstico , Ensaios Antitumorais Modelo de Xenoenxerto
16.
J Med Phys ; 42(1): 1-8, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28405101

RESUMO

This study demonstrated the feasibility and advantages of a hybrid, volumetric arc therapy technique that used two 90° coplanar arcs and two three-dimensional conformal tangential beams in the simultaneous-integrated boost radiotherapy of left-sided breast cancer after breast-conserving surgery. A total of nine patients with stage I, left-sided breast cancer who underwent breast-conserving surgery were selected for this retrospective study. For each patient, a hybrid arc plan was generated and then compared with two hybrid intensity-modulated radiotherapy plans. All plans were optimized using the same objectives and dose constraints. The prescription dose was 50.4 Gy to the planning target volume with simultaneous boost to 60 Gy to the expanded gross target volume in 28 fractions. The differences among these hybrid plans were analyzed by the Kolmogorov-Smirnov test or the Wilcoxon rank sum test. The hybrid arc plans achieved the clinical requirements of target dose coverage and normal tissue (NT) dose constraints. It was found that the hybrid arc plans showed advantages in the conformity index of the expanded gross target volume, the V5 of the heart, the D2 of the left ventricle, and the D2 and V50.4 of NTs. The average beam-on time and monitor units of the hybrid arc plans were significantly lower (P < 0.001).

17.
Adv Sci (Weinh) ; 4(1): 1600214, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28105397

RESUMO

Metal sulfides are commonly used in energy storage and electrocatalysts due to their redox centers and active sites. Most literature reports show that their performance decreases significantly caused by oxidation in alkaline electrolyte during electrochemical testing. Herein, S and N co-doped graphene-based nickel cobalt sulfide aerogels are synthesized for use as rechargeable alkaline battery electrodes and oxygen reduction reaction (ORR) catalysts. Notably, this system shows improved cyclability due to the stabilization effect of the S and N co-doped graphene aerogel (SNGA). This reduces the rate of oxidation and the decay of electronic conductivity of the metal sulfides materials in alkaline electrolyte, i.e., the capacity decrease of CoNi2S4/SNGA is 4.2% for 10 000 cycles in a three-electrode test; the current retention of 88.6% for Co-S/SNGA after 12 000 s current-time chronoamperometric response in the ORR test is higher than corresponding Co-S nanoparticles and Co-S/non-doped graphene aerogels. Importantly, the results here confirm that the Ni-Co-S ternary materials behave as an electrode for rechargeable alkaline batteries rather than supercapacitors electrodes in three-electrode test as commonly described and accepted in the literature. Furthermore, formulas to evaluate the performance of hybrid battery devices are specified.

18.
Biomater Sci ; 5(1): 77-88, 2016 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-27822577

RESUMO

Our previous work reported the development of a proteasome inhibitor, bortezomib (BTZ) encapsulated hollow mesoporous silica nanospheres (HMSNs), as a biocompatible and effective drug-delivery system for non-small cell lung cancer (NSCLC) therapy. Then we found that the tumor-suppressing effect of BTZ or HMSNs-BTZ was compromised in p53 null/mutant NSCLC. In fact, clinical studies have shown a beneficial effect of the combination of p53 gene therapy and chemotherapeutic drugs for patients with NSCLC, especially with the p53 gene null/mutant NSCLC. But there are some safety and toxicity concerns that face the use of gene delivery viral vectors. Here, HMSN-based co-delivery of BTZ and the tumor-suppressor gene p53 was developed for p53 signal impaired NSCLC therapy. The result of the cell viability assay on p53-mutant H1299 cells showed that the half-maximum inhibiting concentration (IC50) of HMSN-PEI-BTZ-p53 was 51% or 25% of that for HMSN-BTZ in 72 or 96 h treatment, respectively. Live/dead staining assay for treated H1299 cells exhibited wider distribution, and higher dead staining was prominent in the HMSNs-PEI-BTZ-p53 group when compared to that of the HMSNs-BTZ group with equivalent BTZ concentration, which was consistent with accumulated p53 expression. Furthermore, the Annexin V-FITC/PI assay suggested restored p53 expression by HMSNs-PEI-BTZ-p53 induced activation of early apoptosis which contributed to enhanced later cell death. Western blotting and real time PCR results showed that several p53 downstream genes responded strongly and synergistically to BTZ function and p53 restored expression (accumulation of p21 and bax, activation of caspase 3, down-regulation of Bcl-2, etc.). Restoration and re-activation of the p53 signal pathway was the basic molecular mechanism for enhanced efficacy of HMSNs-PEI-BTZ-p53 on p53-mutant NSCLC cells.


Assuntos
Bortezomib/uso terapêutico , Carcinoma Pulmonar de Células não Pequenas/terapia , Terapia Genética , Neoplasias Pulmonares/terapia , Proteína Supressora de Tumor p53/genética , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Apoptose/efeitos dos fármacos , Bortezomib/farmacologia , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/genética , Linhagem Celular Tumoral , Humanos , Concentração Inibidora 50 , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , Nanosferas/administração & dosagem , Nanosferas/química , Dióxido de Silício/química
19.
Nanoscale Res Lett ; 11(1): 469, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27766608

RESUMO

Large-area ultrafine MnO2 nanowire arrays (NWA) directly grew on a carbon fiber (CF, used as a substrate) by a simple electrochemical method, forming three-dimensional (3D) hierarchical heterostructures of a CF@MnO2 NWA composite. As an electrode for supercapacitors, the CF@MnO2 NWA composite exhibits excellent electrochemical performances including high specific capacitance (321.3 F g-1 at 1000 mA g-1) and good rate capability. Further, the overall capacitance retention is ~99.7 % capacitance after 3000 cycles. These outstanding electrochemical performances attribute to a large number of transport channels for the penetration of electrolyte and the transportation of ions and electrons of electrodes. The as-prepared CF@MnO2 NWA composite may be a promising electrode material for high-performance supercapacitors.

20.
Mol Pharm ; 13(11): 3934-3944, 2016 11 07.
Artigo em Inglês | MEDLINE | ID: mdl-27744704

RESUMO

Tumor cells can acquire multidrug resistance (MDR) as a result of drug efflux mediated by P-glycoprotein (P-gp). Here we report a targeted delivery system to carry pirarubicin (THP) to MDR breast cancer both in vitro and in vivo. PEG-derivatized vitamin E (PAMV6) amphiphiles loaded with THP were self-assembled in a single step. The PAMV6 micelles showed unimodal size distribution and high drug loading efficiency. Cytotoxicity of PAMV6/THP was higher than that of free THP on MCF-7/ADR cells but comparable to that of THP on MCF-7 cells. PAMV6/THP was able to reverse MDR more than free THP in MCF-7/ADR cells, likely reflecting the remarkably higher intracellular THP concentration in micelle-treated cells and PAMV6-mediated inhibition of P-gp activity. PAMV6/THP micelles were internalized into MCF-7/ADR cells via macropinocytosis and caveolin-mediated endocytosis, further avoiding P-gp-mediated efflux. Mechanistic studies revealed that blank PAMV6 micelles inhibited P-gp activity but did not affect P-gp expression, by significantly reducing mitochondrial membrane potential and slightly decreasing intracellular ATP levels. In a nude mouse xenograft model, PAMV6/THP led to much greater THP accumulation in tumors and much slower tumor growth than free THP. At the same time, PAMV6/THP was associated with significantly less severe bone marrow suppression and organ toxicity than free THP. Our results indicate that this PAMV6-based micelle system holds promise for combating MDR in cancer therapy.


Assuntos
Doxorrubicina/análogos & derivados , Micelas , Trifosfato de Adenosina/metabolismo , Animais , Adesão Celular/efeitos dos fármacos , Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Doxorrubicina/química , Doxorrubicina/uso terapêutico , Humanos , Células MCF-7 , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Camundongos , Camundongos Nus , Ratos , Ratos Wistar
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