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1.
Food Chem Toxicol ; 187: 114550, 2024 May.
Article in English | MEDLINE | ID: mdl-38467300

ABSTRACT

BACKGROUND: The effect of human 8-Oxoguanine DNA Glycosylase (hOGG1) on exogenous chemicals in esophageal squamous cell carcinoma (ESCC) remain unclear. The study plans to determine hOGG1 expression levels in ESCC and possible interactions with known environmental risk factors in ESCC. MATERIAL AND METHODS: We analyzed levels of exposure to urinary nitrosamines in volunteers from high and low prevalence areas by GC-MS. And we performed the interaction between hOGG1 gene and nitrosamine disinfection by-products by analyzing hOGG1 gene expression in esophageal tissues. RESULTS: In ESCC, nitrosamine levels were significantly increased and hOGG1 mRNA expression levels were significantly decreased. There was a statistically significant interaction between reduced hOGG1 mRNA levels and non-tap drinking water sources in ESCC. The apparent indirect association between ESCC and NMEA indicated that 33.4% of the association between ESCC and NMEA was mediated by hOGG1. CONCLUSION: In populations which exposed to high levels of environmental pollutants NDMA, low expression of hOGG1 may promote the high incidence of esophageal cancer in Huai'an. hOGG1 may be a novel mediator in nitrosamine-induced esophageal tumorigenesis.


Subject(s)
Esophageal Neoplasms , Esophageal Squamous Cell Carcinoma , Nitrosamines , Humans , Esophageal Neoplasms/chemically induced , Esophageal Neoplasms/genetics , Esophageal Squamous Cell Carcinoma/chemically induced , Esophageal Squamous Cell Carcinoma/complications , Nitrosamines/toxicity , Cell Transformation, Neoplastic , RNA, Messenger
2.
Biochem Biophys Res Commun ; 534: 511-518, 2021 01 01.
Article in English | MEDLINE | ID: mdl-33220929

ABSTRACT

Dysfunction of long noncoding RNA (lncRNA) is associated with tumorigenesis of various malignancies, including glioma. Previously, lncRNA ARRDC1 antisense RNA 1(ARRDC1-AS1) has been reported to be dysregulated in several tumors. However, the roles of ARRDC1-AS1 in glioma have not been investigated. In this study, we firstly reported that ARRDC1-AS1 expression was distinctly increased in both glioma specimens and cell lines, and high ARRDC1-AS1 expression was associated with advanced clinical progression and poor prognosis of glioma patients. Additionally, STAT1 could activate the transcription of ARRDC1-AS1. Functional studies revealed that knockdown of ARRDC1-AS1 suppressed the proliferation, migration and invasion of glioma cells. Mechanisms exploration indicated ARRDC1-AS1 served as a sponge of miR-432-5p to upregulate PRMT5 expressions. Rescue experiments indicated that knockdown of miR-432-5p reversed the inhibiting effects of ARRDC1-AS1 knockdown on glioma cells. Overall, our findings highlighted the importance of STAT1/ARRDC1-AS1/miR-432-5p/PRMT5 axis in glioma progression and offered novel strategies for glioma treatments.


Subject(s)
Brain Neoplasms/genetics , Glioma/genetics , MicroRNAs/genetics , Protein-Arginine N-Methyltransferases/genetics , RNA, Long Noncoding/genetics , STAT1 Transcription Factor/metabolism , Brain Neoplasms/diagnosis , Brain Neoplasms/metabolism , Cell Line, Tumor , Gene Expression Regulation, Neoplastic , Glioma/diagnosis , Glioma/metabolism , Humans , Prognosis , Transcriptional Activation
3.
Front Neurol ; 11: 950, 2020.
Article in English | MEDLINE | ID: mdl-33178091

ABSTRACT

Background: Benign paroxysmal positional vertigo (BPPV) is a self-limiting and recurrent disease but the cost is considerable. The number of patients with BPPV increased significantly under the quarantine policy in Hangzhou. The unhealthy lifestyle risk factors of BPPV have not yet been investigated. Thus, the objective is to analyze whether an unhealthy lifestyle is a risk factor of BPPV. Methods: One hundred and sixty three patients with idiopathic BPPV aged 22-87 years (BPPV group), and 89 aged 23-92 years sex-matched control subjects (non-BPPV group) were enrolled in this study. All BPPV patients received a definitive diagnosis which excluded secondary BPPV. Non-BPPV cases excluded BPPV, sudden deafness, Meniere's disease, ear or craniofacial surgery, vestibular neuritis, and head trauma history. We obtained a blood lipids profile, serum uric acid, total bilirubin, and related diagnostic information through the electronic medical record system. To get the time of physical activities and recumbent positions, we asked the patient or their family from February 2020 to June 2020, and the rest of the patient's information was acquired by phone or WeChat. Data Analyses: The t-test or chi-squared test, univariate, and multiple logistic regression analyses were performed for the two groups. For each factor, odds ratios were calculated with 95% confidence intervals (CIs). Moreover, test equality of two or more receiver operating characteristic (ROC) analyses were applied to the physical activities, and recumbent position time; area under curve (AUC) measures were calculated with 95% CIs and compared with each other. Results: The BPPV group had unhealthy lifestyles such as poor physical activities, prolonged recumbent position time, and low rate of calcium or VD supplementation in univariate logistic regression analyses (P < 0.05). Poor physical activities and prolonged recumbent position time were independently associated with BPPV in multiple logistic regression models (OR = 18.92, 95% CI: 6.34-56.43, p = 0.00 and OR = 1.15, 95% CI: 1.01-1.33, p < 0.04). In the comparison of ROC curves of recumbent position time and physical activities in identifying BPPV, AUCs were 0.68 (0.61-0.74), and 0.68 (0.63-0.73), respectively. Conclusion: We conclude that poor physical activities and prolonged recumbent position time may be independent risk factors for BPPV patients, but hypertension, hyperuricemia, hyperlipidemia, hemoglobin, diabetes, serum bilirubin, CHD, and CI, may not be.

4.
Adv Sci (Weinh) ; 6(17): 1900766, 2019 Sep 04.
Article in English | MEDLINE | ID: mdl-31508282

ABSTRACT

Red/near-infrared (NIR) emissive carbon nanodots (CNDs) with photoluminescence (PL) quantum yield (QY) of 57% are prepared via an in situ solvent-free carbonization strategy for the first time. 1-Photon and 2-photon cellular imaging is demonstrated by using the CNDs as red/NIR fluorescence agent due to the high PL QY and low biotoxicity. Further study shows that the red/NIR CNDs exhibit multiphoton excited (MPE) upconversion fluorescence under excitation of 800-2000 nm, which involves three NIR windows (NIR-I, 650-950 nm; NIR-II, 1100-1350; NIR-III, 1600-1870 nm). 2-Photon, 3-photon, and 4-photon excited fluorescence of the CNDs under excitation of different wavelengths is achieved. This study develops an in situ solvent-free carbonization method for efficient red/NIR emissive CNDs with MPE upconversion fluorescence, which may push forward the application of the CNDs in bioimaging.

5.
Molecules ; 23(6)2018 May 28.
Article in English | MEDLINE | ID: mdl-29843370

ABSTRACT

We designed a series of novel phenothiazine-1,2,3-triazole hybrids by the molecular hybridization strategy and evaluated their antiproliferative activity against three cancer cell lines (MDA-MB-231, MDA-MB-468 and MCF-7). For the structure-activity relationships, the importance of 1,2,3-triazole and substituents on phenyl ring was explored. Among these phenothiazine-1,2,3-triazole hybrids, compound 9f showed the most potent inhibitory effect against MCF-7 cells, with an IC50 value of 0.8 µM. Importantly, compound 9f could induce apoptosis against MCF-7 cells by regulating apoptosis-related proteins (Bcl-2, Bax, Bad, Parp, and DR5). These potent phenothiazine-1,2,3-triazole hybrids as novel apoptosis inducers might be used as antitumor agents in the future.


Subject(s)
Antineoplastic Agents/chemical synthesis , Apoptosis Regulatory Proteins/genetics , Breast Neoplasms/genetics , Phenothiazines/chemical synthesis , Antineoplastic Agents/chemistry , Antineoplastic Agents/pharmacology , Breast Neoplasms/drug therapy , Cell Cycle/drug effects , Cell Line, Tumor , Cell Proliferation/drug effects , Cell Survival/drug effects , Drug Screening Assays, Antitumor , Female , Gene Expression Regulation, Neoplastic/drug effects , Humans , MCF-7 Cells , Molecular Structure , Phenothiazines/chemistry , Phenothiazines/pharmacology , Structure-Activity Relationship
6.
Exp Ther Med ; 15(4): 3836-3846, 2018 Apr.
Article in English | MEDLINE | ID: mdl-29563983

ABSTRACT

Ischemic stroke is a highly complex pathological process that is divided into acute, subacute and chronic phases. Paeonol is a biologically active natural product with a variety of pharmacological effects, including those on neuronal activity. However, the effects of paeonol on subacute/chronic ischemic stroke have remained to be elucidated. The present study was designed to investigate the effects of paeonol against subacute and chronic cerebral ischemic injury and to explore the possible underlying mechanisms. Male adult Sprague Dawley rats were randomly divided into a sham group (treated with saline), a model group [subjected to middle cerebral artery occlusion (MCAO) and treated with saline] and a paeonol-treated group (MCAO + paeonol at 25 mg/kg). Behavioral impairment, infarct volume and ischemic/contralateral hemispheric ratios were assessed at 72 h and at 28 days after MCAO, respectively. Immunofluorescence was employed to determine the neuronal damage and glial responses after MCAO. Compared with the model group, paeonol treatment significantly attenuated behavioral impairment, ischemic infarct volume and moderate cerebral edema in the ischemic brain at 72 h, as well as brain atrophy at 28 days after reperfusion. Furthermore, paeonol treatment ameliorated neuronal damage in the ischemic core and boundary zone regions at 72 h after reperfusion and in the boundary zone at 28 days after reperfusion. In addition, paeonol treatment reduced the proliferation of astrocytes in the boundary zone, and inhibited microglial activation in the ischemic core and boundary zone regions at 72 h and 28 days after reperfusion. These results demonstrated the protective effects of paeonol against subacute/chronic cerebral ischemia, and the mechanism of action may include subacute/chronic microglial activation and astrocyte proliferation.

7.
Chin J Nat Med ; 15(10): 758-765, 2017 Oct.
Article in English | MEDLINE | ID: mdl-29103461

ABSTRACT

Stroke remains the third leading cause of death and of adult disability worldwide. Vascular occlusion, followed by ischemic cascade, leads to irreversible tissue injury. Recombinant tissue plasminogen activator is the only FDA approved drug for the current treatment of acute ischemic stroke. However, traditional Chinese medicine has a long history and rich clinical experience in the treatment and rehabilitation of ischemic stroke. Using a classical middle cerebral artery occlusion (MCAO) stroke model, we tested the effectiveness of Yiqihuoxue calm wind (YCW) capsule on neurological function, gross pathology and oxidative stress status in MCAO rats. YCW capsule (3.36 and 6.72 g·kg-1 of crude drug) could significantly lower Longa's score and superoxide dismutase (SOD) level, together with less necrotic cells and infarcted area. In addition to elevated MDA and downregulated iNOS expression, YCW capsule exhibited its neuroprotective effects via free radical scavenging and NO inhibition.


Subject(s)
Brain Ischemia/drug therapy , Neuroprotective Agents/administration & dosage , Stroke/drug therapy , Animals , Brain Ischemia/genetics , Brain Ischemia/metabolism , Humans , Male , Malondialdehyde/metabolism , Oxidative Stress/drug effects , Rats , Rats, Sprague-Dawley , Stroke/genetics , Stroke/metabolism , Superoxide Dismutase/metabolism
8.
Nan Fang Yi Ke Da Xue Xue Bao ; 36(7): 1018-20, 2016 Jun 20.
Article in Chinese | MEDLINE | ID: mdl-27435787

ABSTRACT

An esophageal squamous cell carcinoma measuring 18.3 cm in length and 5 cm in diameter was found in the mediastinum of a 53-year man. The patient underwent a modified 3-stage esophagectomy and an esophagogastrostomy at the cervical level (Wu's method). The operation was performed smoothly and the patient recovered uneventfully after the operation. The patient was followed up for 6 months after discharge and reported no difficulties in eating with improved quality of life. This case represents the world's longest esophageal cancer that had been surgically removed. Local advanced esophageal cancer should be removed immediately to prevent potential occurrence of esophageal obstruction, tracheoesophageal fistula or aorto-esophageal fistula.


Subject(s)
Carcinoma, Squamous Cell/surgery , Esophageal Neoplasms/surgery , Esophagectomy , Esophageal Fistula , Esophageal Squamous Cell Carcinoma , Esophageal Stenosis , Female , Humans , Male , Middle Aged , Quality of Life
9.
ACS Appl Mater Interfaces ; 8(27): 17334-42, 2016 Jul 13.
Article in English | MEDLINE | ID: mdl-27323648

ABSTRACT

Cu2ZnSn(S,Se)4 (CZTSSe) films were deposited on the Mo-coated glass substrates, and the CZTSSe-based solar cells were successfully fabricated by a facile solution method and postselenization technique. The influencing mechanisms of the selenization temperature and time on the power conversion efficiency (PCE), short-circuit current density (Jsc), open-circuit voltage (Voc), and fill factor (FF) of the solar cell are systematically investigated by studying the change of the shunt conductance (Gsh), series resistance (Rs), diode ideal factor (n), and reversion saturation current density (J0) with structure and crystal quality of the CZTSSe film and CZTSSe/Mo interface selenized at various temperatures and times. It is found that a Mo(S1-x,Sex)2 (MSSe) layer with hexagonal structure exists at the CZTSSe/Mo interface at the temperature of 500 °C, and its thickness increases with increasing selenization temperature and time. The MSSe has a smaller effect on the Rs, but it has a larger influence on the Gsh, n, and J0. The PCE, Voc, and FF change dominantly with Gsh, n, and J0, while Jsc changes with Rs and Gsh, but not Rs. These results suggest that the effect of the selenization temperature and time on the PCE is dominantly contributed to the change of the CZTSSe/CdS p-n junction and CZTSSe/MSSe interface induced by variation of the quality of the CZTSSe film and thickness of MSSe in the selenization process. By optimizing the selenization temperature and time, the highest PCE of 7.48% is obtained.

10.
Onco Targets Ther ; 8: 3449-55, 2015.
Article in English | MEDLINE | ID: mdl-26640385

ABSTRACT

OBJECTIVE: The disheveled, Egl-10, and pleckstrin (DEP) domain containing mammalian target of rapamycin (mTOR)-interacting protein (DEPTOR) is a binding protein containing mTOR complex 1 (mTORC1), mTOR complex 2 (mTORC2), and an endogenous mTOR inhibitor. DEPTOR shows abnormal expressions in numerous types of solid tumors. However, how DEP-TOR is expressed in esophageal squamous cell carcinoma (ESCC) remains elusive. METHODS: The expression of DEPTOR in 220 cases of ESCC and non-cancerous adjacent tissues was detected by immunohistochemistry. DEPTOR levels in ESCC and paired normal tissue were quantified using reverse transcription-polymerase chain reaction and Western blot analysis to verify the immunohistochemical results. The relationship between DEPTOR expression and the clinicopathological features of ESCC was analyzed based on the results of immunohistochemistry. Finally, we analyzed the relationship between DEPTOR expression and the prognosis of patients with ESCC. RESULTS: Immunohistochemical staining showed that the expression rate of DEPTOR in ESCC tissues was significantly increased. DEPTOR mRNA and protein expression was significantly higher in ESCC tissues than in normal adjacent esophageal squamous tissues. High DEPTOR expression was significantly correlated with regional lymph node status in the TNM stage of patients with ESCC. Kaplan-Meier survival curves showed that the rate of overall survival was significantly lower in patients with high DEPTOR expression than in those with low DEPTOR expression. Additionally, high DEPTOR expression was an independent prognostic predictor for ESCC patients. CONCLUSION: High DEPTOR expression is an independent prognostic biomarker indicating a worse prognosis for patients with ESCC.

11.
ACS Appl Mater Interfaces ; 7(37): 20600-6, 2015 Sep 23.
Article in English | MEDLINE | ID: mdl-26325521

ABSTRACT

Mixed-phase ZnMgO (m-ZMO) thin films with a single absorption edge tuning from ∼3.9 to ∼4.8 eV were realized on a-face sapphire (a-Al2O3) by plasma-assisted molecular beam epitaxy. The small lattice mismatch of both ZnO and MgO with a-Al2O3 should be responsible for the single and controllable absorption edge. Metal-semiconductor-metal (MSM) photodetectors were fabricated based on these m-ZMO films, and the devices have the single cutoff wavelength, which can be tuned from 335 to 275 nm. These devices possess low dark current (78 pA for m-Z0.67M0.33O, 11 pA for m-Z0.59M0.41O, and 4 pA for m-Z0.39M0.61O at 40 V) and high responsivity (434 A/W for m-Z0.67M0.33O, 89.8 A/W for m-Z0.59M0.41O, and 3.7 A/W for m-Z0.39M0.61O at 40 V). Further response study reveals that the 90-10% decay time of m-Z0.67M0.33O, m-Z0.59M0.41O, and m-Z0.39M0.61O is around 37, 30, and 0.7 ms, respectively. Large amounts of heterojunction interfaces between wurtzite ZMO and cubic rock-salt ZMO could be responsible for the low dark current and high responsivity of our mixed-phase devices. The excellent comprehensive performance of m-ZMO UV photodetectors on a-Al2O3 suggests that m-ZMO UV photodetectors should have great applied potential.

12.
J Photochem Photobiol B ; 149: 51-7, 2015 Aug.
Article in English | MEDLINE | ID: mdl-26046749

ABSTRACT

Fullerene (C60) L-phenylalanine derivative attached with poly (lactic acid) (C60-phe-PLA) was developed to prepare injectable Mitoxantrone (MTX) multifunctional implants. C60-phe-PLA was self-assembled to form microspheres consisting of a hydrophilic antitumor drug (MTX) and a hydrophobic block (C60) by dispersion-solvent diffusion method. The self-assembled microspheres showed sustained release pattern almost 15days in vitro release experiments. According to the tissue distribution of C57BL mice after intratumoral administration of the microspheres, the MTX mainly distributed in tumors, and rarely in heart, liver, spleen, lung, and kidney. Photodynamic antitumor efficacy of blank microsphere was realized. Microspheres afforded high antitumor efficacy without obvious toxic effects to normal organs, owing to its significantly increased MTX tumor retention time, low MTX levels in normal organs and strong photodynamic activity of PLA-phe-C60. These C60-phe-PLA microspheres may be promising for the efficacy with minimal side effects in future treatment of solid tumors.


Subject(s)
Drug Carriers/chemistry , Fullerenes/chemistry , Lactic Acid/chemistry , Mitoxantrone/chemistry , Mitoxantrone/pharmacology , Photochemotherapy/methods , Polymers/chemistry , Animals , Antineoplastic Agents/chemistry , Antineoplastic Agents/pharmacokinetics , Antineoplastic Agents/pharmacology , Chemistry, Pharmaceutical , Combined Modality Therapy , Drug Liberation , Injections , Male , Melanoma/drug therapy , Mice , Microspheres , Mitoxantrone/pharmacokinetics , Phenylalanine/chemistry , Polyesters , Xenograft Model Antitumor Assays
13.
Photochem Photobiol Sci ; 14(6): 1197-206, 2015 Jun.
Article in English | MEDLINE | ID: mdl-25997891

ABSTRACT

Recently, porous carbons have showed great potential in many areas. In this study, TiO2-doped mesoporous carbonaceous (TiO2@C) nanoparticles were obtained by a simple one-pot hydrothermal treatment, folic acid (FA) was conjugated to TiO2@C through an amide bond, then Mitoxantrone HCl (MTX) was adsorbed onto TiO2@C-FA and a drug delivery system, TiO2@C-FA/MTX was obtained. TiO2@C-FA/MTX showed a much faster MTX release at pH 4.5 than at pH 6.0 and pH 7.4. Furthermore, compared with free MTX, this drug delivery system showed a dose-dependent cytotoxicity by varying the irradiance, and afforded higher antitumor efficacy in cultured PC3 cells in vitro. The ability of TiO2@C-FA/MTX to combine chemotherapy with photodynamic activity enhanced the cancer cell killing effect in vitro, demonstrating that TiO2@C-FA/MTX has a great potential for cancer therapy in the future.


Subject(s)
Folic Acid/therapeutic use , Mitoxantrone/therapeutic use , Nanocomposites/therapeutic use , Photochemotherapy/methods , Titanium/chemistry , Cell Death/drug effects , Cell Line, Tumor , Folic Acid/chemistry , Folic Acid/pharmacology , Humans , Mitoxantrone/chemistry , Mitoxantrone/pharmacology , Nanocomposites/chemistry , Porosity , Spectroscopy, Fourier Transform Infrared
14.
Med Sci Monit ; 20: 2817-23, 2014 Dec 29.
Article in English | MEDLINE | ID: mdl-25544260

ABSTRACT

BACKGROUND: Although many epidemiology studies have investigated the methylenetetrahydrofolate reductase (MTHFR) gene polymorphisms and their associations with lung cancer (LC), definite conclusions cannot be drawn. To clarify the effects of MTHFR polymorphisms on the risk of LC, we performed a meta-analysis in Chinese populations. MATERIAL/METHODS: Related studies were identified from PubMed, Springer Link, Ovid, Chinese Wanfang Data Knowledge Service Platform, Chinese National Knowledge Infrastructure (CNKI), and Chinese Biology Medicine (CBM) until 16 February 2014. Pooled odds ratios (ORs) and 95% confidence intervals (CIs) were used to assess the strength of the associations. RESULTS: A total of 11 studies with 2487 LC cases and 3228 controls were included in this meta-analysis. Overall, no significant association was found between MTHFR C677T polymorphism and LC risk when all studies in Chinese populations were pooled into this meta-analysis. In subgroup analyses stratified by geographical location and source of controls, significantly increased risk was found in North China (T vs. C: OR=1.28, 95% CI: 1.14-1.44; TT vs. CC: OR=1.67, 95% CI: 1.33-2.10; TT + CT vs. CC, OR=1.39, 95% CI=1.15-1.69; TT vs. CC + CT: OR=1.46, 95% CI: 1.03-2.06) and in population-based studies (TT vs. CC: OR=1.37, 95% CI: 1.14-1.65; TT vs. CC + CT: OR=1.25, 95% CI: 1.07-1.45). CONCLUSIONS: This meta-analysis provides evidence that MTHFR C677T polymorphism may contribute to LC development in North China. Studies with larger sample sizes and wider spectrum of populations are warranted to verify this finding.


Subject(s)
Genetic Predisposition to Disease , Lung Neoplasms/genetics , Methylenetetrahydrofolate Reductase (NADPH2)/genetics , Polymorphism, Single Nucleotide/genetics , China , Confidence Intervals , Humans , Odds Ratio , Publication Bias , Risk Factors
15.
Photochem Photobiol ; 90(5): 1144-9, 2014.
Article in English | MEDLINE | ID: mdl-24913433

ABSTRACT

This report explores some properties of 80-200 nm nanoparticles containing 5-aminolevulinic acid (ALA) and fullerene (C60) for photodynamic therapy (PDT). Compared with ALA, the nanoparticles yielded more protoporphyrin IX (PpIX) formation in cells and tissues and to a significant improvement in antitumor efficacy in tumor-bearing mice. Maximum levels of PpIX were obtained 4 h after administration and selective PpIX formation in tumor was observed. These nanoparticles appear to be a useful vehicle for drug delivery purposes. In this study, a procedure for preparing fullerene nanoparticles containing ALA was developed. The product alone exhibited no detectable toxicity in the dark and was superior to ALA alone in promoting PpIX biosynthesis and PDT efficacy both in culture and in a murine tumor model. These results suggest that this procedure could be the basis for an improved PDT protocol for cancer control.


Subject(s)
Aminolevulinic Acid/administration & dosage , Fullerenes/chemistry , Melanoma, Experimental/drug therapy , Nanoparticles/chemistry , Photochemotherapy , Photosensitizing Agents/pharmacology , Skin Neoplasms/drug therapy , Aminolevulinic Acid/metabolism , Animals , Cell Survival/drug effects , Cell Survival/radiation effects , Disease Models, Animal , Humans , Injections, Intravenous , Light , Melanoma, Experimental/blood , Melanoma, Experimental/pathology , Mice , Photosensitizing Agents/chemistry , Photosensitizing Agents/metabolism , Protoporphyrins/chemistry , Protoporphyrins/metabolism , Skin Neoplasms/blood , Skin Neoplasms/pathology , Tumor Burden/drug effects , Tumor Burden/radiation effects
16.
J Nanosci Nanotechnol ; 14(6): 4513-8, 2014 Jun.
Article in English | MEDLINE | ID: mdl-24738422

ABSTRACT

The properties of an ideal photosensitizer are water solubility, low cytotoxicity in the dark, high ability to produce reactive oxygen species (ROS). The characteristics of water-soluble fullerene (C60) amino acid nanoparticles as a photosensitizer were evaluated. C60 modified with l-phenylalanine (C60-phe) or glycine (C60-gly) was very efficient to carry out photodynamic activity leading to cleavage of plasmid DNA in vitro. These C60 amino acid nanoparticles were the most active photosensitizer against human Liver cancer cells and induced cancer cells apoptosis after illumination. However, these derivatives exhibited no significant cytotoxicity in dark. It produced diffuse intracellular fluorescence when 2',7'-dichlorfluorescein-diacetate (DCFH-DA) was added as an ROS probe, suggesting phototoxicity of these derivatives related with the generation of intracellular ROS. These findings indicate that these fullerene derivatives may be excellent candidate PDT enhancing agents.


Subject(s)
Fullerenes/therapeutic use , Glycine/therapeutic use , Liver Neoplasms/drug therapy , Nanoconjugates/therapeutic use , Nanoparticles/therapeutic use , Phenylalanine/therapeutic use , Photochemotherapy/methods , Cell Line, Tumor , Fullerenes/chemistry , Glycine/chemistry , Humans , Liver Neoplasms/pathology , Nanoconjugates/chemistry , Nanoconjugates/ultrastructure , Nanoparticles/chemistry , Nanoparticles/ultrastructure , Phenylalanine/chemistry , Photosensitizing Agents/chemical synthesis , Photosensitizing Agents/therapeutic use , Treatment Outcome
17.
Opt Lett ; 38(12): 2113-5, 2013 Jun 15.
Article in English | MEDLINE | ID: mdl-23938994

ABSTRACT

MgZnO heterostructure light-emitting devices (LEDs) have been fabricated from p-Mg(0.35)Zn(0.65)O/n-Mg(0.20)Zn(0.80)O structures, and the p-type Mg(0.35)Zn(0.65)O film was realized using a lithium-nitrogen codoping method. Obvious ultraviolet emission peaked at around 355 nm dominates the electroluminescence (EL) spectra of the device at room temperature, which comes from the near-band-edge emission of the n-type Mg(0.20)Zn(0.80)O film. This is the first report on MgZnO heterostructured LEDs and the shortest EL emission ever reported in ZnO-based p-n junction LEDs to the best of our knowledge.

18.
J Zhejiang Univ Sci B ; 14(7): 615-20, 2013 Jul.
Article in English | MEDLINE | ID: mdl-23825147

ABSTRACT

A new liquid chromatographic method has been developed for the chiral separation of the enantiomers of mandelic acid and their derivatives 2-chloromandelic acid, 4-hydroxymandelic acid, 4-methoxymandelic acid, and 3,4,5-trismethoxymandelic acid. The enantiomers were separated by a CHIRALPAK(®) IC (250 mm×4.6 mm, 5 µm). Mandelic acid, 4-methoxymandelic acid, and 3,4,5-trismethoxymandelic acid were baseline resolved (resolution factor (RS)=2.21, RS=2.14, and RS=3.70, respectively). In contrast, the enantioselectivities between CHIRALPAK(®) IC and 2-chloromandelic acid and 4-hydroxymandelic acid investigated were low. By comparing the chromatographs of mandelic acid enantiomers and mandelic acid spiked with (R)-mandelic acid, it was determined that the first effluent was (R)-mandelic acid.


Subject(s)
Cellulose/chemistry , Chromatography, High Pressure Liquid/methods , Mandelic Acids/analysis , Mandelic Acids/isolation & purification , Alcohols/chemistry , Chemistry Techniques, Analytical , Stereoisomerism , Temperature , Trifluoroacetic Acid/chemistry
19.
Nanoscale ; 4(9): 2843-6, 2012 Apr 28.
Article in English | MEDLINE | ID: mdl-22441877

ABSTRACT

Vertically aligned ZnO nanowires have been prepared, and structural characterization shows that the nanowires have relatively high crystalline quality. The dominant free exciton emission and the appearance of B-type exciton emissions at low temperatures reveal the high optical quality of the nanowires. Au-MgO-ZnO nanowire structures have been constructed, and random lasing has been observed from the structure under the injection of continuous current.

20.
Sensors (Basel) ; 12(2): 1280-7, 2012.
Article in English | MEDLINE | ID: mdl-22438709

ABSTRACT

To increase the responsivity is one of the vital issues for a photodetector. By employing ZnO as a representative material of ultraviolet photodetectors and Si as a representative material of visible photodetectors, an impact ionization process, in which additional carriers can be generated in an insulating layer at a relatively large electric field, has been employed to increase the responsivity of a semiconductor photodetector. It is found that the responsivity of the photodetectors can be enhanced by tens of times via this impact ionization process. The results reported in this paper provide a general route to enhance the responsivity of a photodetector, thus may represent a step towards high-performance photodetectors.


Subject(s)
Heavy Ions , Photometry/instrumentation , Semiconductors , Transducers , Zinc Oxide/chemistry , Equipment Design , Equipment Failure Analysis , Light , Sensitivity and Specificity , Zinc Oxide/radiation effects
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