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1.
Abdom Radiol (NY) ; 2020 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-32006072

RESUMO

OBJECTIVE: To assess the clinical efficacy and safety of computed tomography-guided radiofrequency ablation(CT-RFA) combined with transarterial embolization(TAE) assisted by a three-dimensional visualization ablation planning system(3DVAPS) for hepatocellular carcinoma(HCC) in challenging locations. METHODS: Data from 62 treatment-naive patients with hepatocellular carcinoma(HCC), with 83 lesions in challenging locations, and who met the Milan criteria and underwent CT-RFA between June 2013 and June 2016 were reviewed. Patients were divided into one of two groups according to different treatment modalities: study group (TAE combined with RFA assisted by 3DVAPS [n = 32]); and control (RFA only [n = 30]). Oncological outcomes included ablation-related complications, local tumor progression (LTP), and overall survival (OS). Univariate and multivariate Cox proportional hazards regression analyses were performed to assess risk factors associated with LTP and OS. RESULTS: HCC lesions (mean size, 1.9 ± 1.0 mm in diameter) abutting the gastrointestinal tract (n = 25), heart and diaphragm (n = 21), major vessels (n = 13), and gallbladder (n = 3) were treated. A significant difference was detected in LTP between the two groups (P = 0.034), with no significant difference in OS between the two groups (P = 0.193). There were no severe complications related to ablation. Univariate analysis revealed that sex (P = 0.046) and child-turcotte-pugh (CTP) grade (P<0.001) were risk factors for OS, whereas CTP grade and treatment method (P<0.001) were risk factors for LTP. Multivariate analysis revealed that CTP grade B (P = 0.005) was independently associated with poor OS, and RFA alone (P<0.001) was independently associated with poor LTP. CONCLUSION: CT-RFA combined with TAE assisted by a 3DVAPS provided ideal clinical efficiency for HCC in challenging locations and was a highly safe treatment modality.

2.
Sci Rep ; 10(1): 199, 2020 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-31932711

RESUMO

It is well known that when a laser is reflected from a rough surface or transmitted through a diffusive medium, a speckle pattern will be formed at a given observation plane. An important parameter of speckle is its size, which for the case of homogeneous illumination, well-known relations for its computation have been derived. This is not the case for structured light beams of non-homogeneous intensity and phase distribution. Here, we propose and demonstrate, using Hermite- and Laguerre-Gaussian light modes, that the mean size of the speckle generated by these structured light beams can be measured assuming a homogeneous illumination. We further provide with mathematical expressions that relate the speckle size to the generalised definition of "spot size". To reinforce our assessment, we compare the mean speckle size generated by structured light modes with that generated by wave fronts of constant phase and amplitude and show that in both cases the mean speckle size is almost identical. Our findings reveal a fundamental property of speckle, which will be of great relevance in many speckle-based applications and will pave the way towards the development of novel applications.

3.
Nat Commun ; 11(1): 79, 2020 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-31911589

RESUMO

Mice are widely used as experimental models for gut microbiome (GM) studies, yet the majority of mouse GM members remain uncharacterized. Here, we report the construction of a mouse gut microbial biobank (mGMB) that contains 126 species, represented by 244 strains that have been deposited in the China General Microorganism Culture Collection. We sequence and phenotypically characterize 77 potential new species and propose their nomenclatures. The mGMB includes 22 and 17 species that are significantly enriched in ob/ob and wild-type C57BL/6J mouse cecal samples, respectively. The genomes of the 126 species in the mGMB cover 52% of the metagenomic nonredundant gene catalog (sequence identity ≥ 60%) and represent 93-95% of the KEGG-Orthology-annotated functions of the sampled mouse GMs. The microbial and genome data assembled in the mGMB enlarges the taxonomic characterization of mouse GMs and represents a useful resource for studies of host-microbe interactions and of GM functions associated with host health and diseases.

4.
Subst Use Misuse ; 55(1): 156-166, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31474171

RESUMO

Background and Objectives: Based on the theory of reasoned action, the present study investigated the relative effects of drinking outcome expectancies and parental norms, as well as the mediating effect of drinking motivations, on hazardous drinking in Chinese university students. Method: A sample of Chinese university students in Hong Kong and Macao (N = 973, M = 19.82, SD = 1.57, 48.9% males), who reported drinking in the past 3 months, voluntarily completed an anonymous questionnaire. Path analysis was used to test the effects of the variables on hazardous drinking. Results: All the psychosocial variables showed positive correlations with hazardous drinking. In the path model, controlling for sex, parental norms had both direct and indirect effects on hazardous drinking through social and enhancement motivations. Courage had the strongest indirect effect on drinking behavior through social, enhancement, and coping motivations, whereas the relationship between tension reduction and hazardous drinking was mediated by enhancement and coping motivations. Sociality and sexuality only had indirect effect through social and coping motivations respectively. Negative outcome expectancies had no direct nor indirect effects on hazardous drinking. Conclusions: Perceived approval from parents and positive alcohol outcome expectancies may enhance individuals' tendency to engage in hazardous drinking by increasing their motivation to drink to be social, for enjoyment, and to cope with problems. Parents should explicitly show their disapproval of their children's drinking, and education efforts should focus on decreasing positive outcome expectancies and associated motivations for drinking among Chinese university students.

5.
Huan Jing Ke Xue ; 40(10): 4319-4329, 2019 Oct 08.
Artigo em Chinês | MEDLINE | ID: mdl-31854798

RESUMO

To investigate the diurnal variations and sources of water-soluble compounds in Liaocheng City, PM2.5 samples were collected between January and February 2017. The PM2.5 samples were analyzed for the compositions, concentrations, and sources of water-soluble inorganic ions, oxalic acid, and levoglucosan. The sources of these chemical compound were investigated using principal component analysis (PCA) and multiple linear regression (MLR) modeling. The results showed that the mass concentrations of PM2.5during the nighttime were higher than those during the daytime, and the average concentrations exceeded the National Ambient Air Quality Standard (GB 3095-2012) by more than 1.8 times. Moreover, atmospheric pollution was worse during the day than during the night. SNA (SO42-, NO3-, and NH4+) were the dominant species among the inorganic ions, the relative abundance of which with respect to the total concentrations of inorganic ions was 73.4% and 77.1% during the daytime and nighttime, respectively. The ratios of anion to cation equivalents (AE/CE) were less than one, suggesting that the PM2.5 was slightly alkaline, and the degree of acidity at night was stronger than during the day. The results of the correlation analyses suggested that aqueous-phase oxidation was the major formation pathway of oxalic acid, which is driven by acid-catalyzed oxidation. The oxalic acid was mainly influenced by biomass burning during the winter in Liaocheng City. The results of the PCA-MLR model suggested that water-soluble compounds in Liaocheng City were mostly from vehicular emissions and secondary oxidation, biomass burning, while the impacts of mineral dust and coal burning were relatively minor.

6.
Huan Jing Ke Xue ; 40(9): 3875-3885, 2019 Sep 08.
Artigo em Chinês | MEDLINE | ID: mdl-31854849

RESUMO

To investigate the mass concentrations, sources, and health effects of polycyclic aromatic hydrocarbons (PAHs) in ambient particulate matter (PM) in Liaocheng City during winter, 14 types of PAHs in PM2.5 were determined from January to February of 2017. The sources of the PAHs were analyzed by using diagnostics ratios and the principal component analysis (PCA)-multiple linear regression (MLR) model,and the health risk of PAHs was assessed by BaP equivalent concentrations (BaPeq) and incremental lifetime cancer risk (ILCR). The results showed that the mass concentrations of PAHs in PM2.5 during winter were (64.89±48.23) ng·m-3, Fla, Pyr, and Chry were predominant species, accounting for 15.5%, 12.8%, and 12.7% of the total concentrations of PAHs, respectively. Moreover, the ring distribution of the PAHs was dominated by four-ring PAHs. The pollution during the pre-Spring Festival and firework Ⅱwere the most severe during the sampling period. The results of the PCA-MLR model suggested that PAHs originated mostly from coal burning, biomass burning, and vehicle emissions. The toxicity exposure index (TEQ) in Liaocheng City during winter was (6.37±4.92) ng·m-3. The results of the risk model revealed that the ILCR of adults was higher than that of children, and both groups of ILCR for winter were in the range of the risk threshold. This suggests that a potential risk in terms of inhalation PAH exposure for residents in Liaocheng City.


Assuntos
Poluentes Atmosféricos , Saúde Ambiental , Hidrocarbonetos Policíclicos Aromáticos , Medição de Risco , Adulto , Criança , China , Cidades , Monitoramento Ambiental , Humanos , Material Particulado , Estações do Ano
7.
J Exp Clin Cancer Res ; 38(1): 443, 2019 10 31.
Artigo em Inglês | MEDLINE | ID: mdl-31666112

RESUMO

In the original publication of this article [1], the author would like to revise Figure 4.

8.
Hum Mutat ; 2019 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-31696999

RESUMO

To assess the spectrum of pediatric clinical phenotypes in TJP2 disease, we reviewed records of our seven patients in whom intrahepatic cholestasis was associated with biallelic TJP2 variants (13; 12 novel) and correlated clinical manifestations with mutation type. The effect of a splicing variant was analyzed with a minigene assay. The effects of three missense variants were analyzed with protein expression in vitro. Our patients had both remitting and persistent cholestasis. Three exhibited growth retardation. Six responded to treatment with cholestyramine, ursodeoxycholic acid, or both. Two had cholecystolithiasis. None required liver transplantation or developed hepatocellular or cholangiocellular malignancy. None manifested extrahepatic disease not attributable to effects of cholestasis. The variant c.2180-5T>G resulted in exon 15 skipping with in-frame deletion of 32 amino acid residues in TJP2. The three missense variants decreased but did not abolish TJP2 expression. Patients with truncating or canonical splice-site variants had clinically more severe disease. TJP2 disease in children includes a full clinical spectrum of severity, with mild or intermittent forms as well as the severe and minimal forms hitherto described. Biallelic TJP2 variants must be considered in children with clinically intermittent or resolved intrahepatic cholestasis.

9.
Cancer Sci ; 2019 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-31742824

RESUMO

Identification of deleterious variants in hereditary breast and ovarian cancer (HBOC) susceptibility genes allows for increased clinical surveillance and early detection, and could predict the response to poly (ADP-ribose) polymerase (PARP) inhibitor in patients with advanced ovarian carcinomas. To determine the prevalence and clinical prediction factors for HBOC syndrome, 882 selected individuals underwent multigene panel testing for HBOC risk assessment during the period from January 2015 to March 2018. Overall, 176 deleterious mutations were observed in 19.50% (n = 172) of individuals. Twenty-six of 176 mutations could not be retrieved in related public databases and were considered to be novel. Among patients with ovarian cancer, 115 deleterious mutations were identified in 429 patients (48.6%) with significant enrichment for a family history of breast or ovarian cancer syndrome (P < .05). In the breast cancer subgroup, 31 deleterious mutations were identified in 261 patients. Besides BRCA1 (8; 25.8%) and BRCA2 (11; 35.5%), the most frequently occurring genes, an additional 12 deleterious mutations (38.7%) were found in seven other susceptibility genes. Higher mutation incidence (57.9%) was observed in subjects with histories of breast and ovarian cancer. Our results highlighted the genetic heterogeneity of HBOC and the efficiency of a multigene panel in carrying out risk assessment.

10.
Nano Lett ; 19(11): 7866-7876, 2019 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-31594301

RESUMO

Nanoscale photodynamic therapy (PDT) is an appealing antitumor modality for which apoptosis is the major mechanism of toxicity induction. It was postulated that the highly reactive singlet oxygen in PDT could deplete glutathione (GSH) and activate ferroptosis, the extent to which could be further manipulated by a redox-responsive nanocarrier. To validate this, a disulfide-bearing imidazole ligand coordinated with zinc to form an all-active metal organic framework (MOF) nanocarrier where a photosensitizer (chlorin e6/Ce6) was encapsulated. Regardless of light irradiation, the Ce6-loaded nanocarrier caused the depletion of intracellular GSH via the disulfide-thiol exchange reaction in a murine mammary carcinoma cell line (4T1). The GSH depletion further caused the inactivation of glutathione peroxide 4 (GPX4) and the enhancement of cytotoxicity that was alleviated by ferroptosis inhibitors. The superior in vivo antitumor efficacy of the all-active nanocarrier was corroborated in a 4T1 tumor-bearing mice model regarding tumor growth suppression and animal survival rate. The coadministration of an iron chelator weakened the antitumor potency of the nanocarrier due to ferroptosis inhibition, which was supported by the fact of tumor growth upsurge and the recovered GPX4 activity. The current work highlights the contribution of ferroptotic machinery to antitumor PDT via an activatable, adaptable, all-active MOF nanocarrier.

11.
Bioorg Chem ; 93: 103283, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31585260

RESUMO

Phosphatidylinositol 3-kinase (PI3K) pathway regulates various cellular processes, such as proliferation, growth, autophagy and apoptosis. Class I PI3K is frequently mutated and overexpressed in a lot of human cancers and PI3K was considered as a target for therapeutic treatment of cancer. In this study, we designed and synthesized a series of 1,6-disubstituted-1H-benzo[d]imidazoles derivatives and evaluated their anticancer activity and the compound 8i was identified as a lead compound. Compound 8i with the most potent antiproliferative activity was selected for further biological mechanism. The PI3K kinase assay have shown potent efficiency against four subtypes of PI3K with an IC50 of 0.5-1.9 nM. Molecular docking showed a possible formation of H-bonding with essential amino acid residues. Meanwhile, western blot assay indicated that 8i inhibited cell proliferation via suppression of PI3K kinase activity and subsequently blocked PI3K/Akt pathway activation in HCT116 cells. In addition, 8i could inhibit the migration and invasion ability of HCT116 cells and could induce apoptosis of HCT116 cells.

12.
J Exp Clin Cancer Res ; 38(1): 409, 2019 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-31533816

RESUMO

BACKGROUND: ATPase associated with a variety of cellular activities (AAA ATPase) family members are closely linked to tumor formation and progression. However, their roles in hepatocellular carcinoma (HCC) largely remain unclear. METHODS: Bioinformatic analyses of public databases were used to excavate the potential AAA ATPases that may contribute to HCC, and thyroid hormone receptor interactor 13 (TRIP13) was selected to following researches because of its most prominently differential expression. Western blot, qRT-PCR and immunohistochemistry were used to detect the expression of TRIP13 in HCC tissues, and then the relationship between TRIP13 expression and clinicopathological parameters were evaluated. Finally, its functions and potential mechanisms were investigated through a series gain- and loss-of-function strategies both in vitro and in vivo. RESULTS: TRIP13 was significantly overexpressed in HCC tissues and high level of TRIP13 was closely correlated with a worse clinical outcome. Functionally, elevated TRIP13 facilitated cell proliferation, migration, invasion, and promoted cellular epithelial-mesenchymal transition (EMT) in vitro, while promote tumor growth and lung metastasis in vivo. Mechanistically, TRIP13 interacted with ACTN4 and positively regulated its expression, thus activating the AKT/mTOR pathway to drive tumor progression. Moreover, miR-192-5p served as an upstream regulator of TRIP13 by directly binding to TRIP13 mRNA 3' UTR, which may partially explain the high expression of TRIP13 in HCC. CONCLUSION: Our findings identified TRIP13 as a promising candidate oncogene in HCC, and TRIP13 induced cell migration, invasion and metastasis of HCC through the AKT/mTOR signaling via interacting with ACTN4.

13.
Addict Behav ; 99: 106070, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31430620

RESUMO

AIMS: Given the high prevalence of Internet gaming disorder (IGD) among university students and the beneficial effects of positive psychological factors on mental illness, the present longitudinal research aimed to investigate whether purpose in life and social support yields long-term results in protecting university students from IGD. METHODS: We recruited 469 Chinese university students to voluntarily fill out an anonymous questionnaire at baseline, and 283 of them were followed up and given similar measures after one year. RESULTS: The prevalence of probable IGD at the baseline and follow-up surveys was 14.8% and 9.9% respectively. Purpose in life and social support were negatively correlated with IGD symptoms in both surveys (p < .05). The results of a cross-lagged analysis showed that purpose in life, but not social support, assessed at baseline predicted fewer IGD symptoms at follow-up (p < .001). In addition, social support and purpose in life predicted one another across time. CONCLUSIONS: The prevalence of probable IGD was high among Chinese university students. Purpose in life was shown to be an effective significant protective factor against IGD, while the effect of social support might be indirect. Positive psychology interventions, which promote the search for and attainment life purpose, may be incorporated in school-based program for IGD prevention.

15.
Vascul Pharmacol ; 121: 106582, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31437529

RESUMO

BACKGROUND: The contentious effects of estrogen therapy on the risk of postmenopausal cardiovascular disease (CVD) indicate that this type of atherosclerosis is not solely induced by estrogen deficiency. Other sex hormones such as elevated luteinizing hormone (LH) may also affect CVD risk in this population. We therefore explored the relationship between LH and atherosclerosis in ovariectomized (OVX) female mice. METHODS: Aortic atherosclerotic lesions were assessed in OVX ApoE knock out (ApoE-/-) female mice administered with LH. Human umbilical vascular endothelial cells (HUVECs) were cultured as cell model. The influence of LH on NO release, phosphorylated endothelial nitric oxide synthase (eNOS) and Akt levels were evaluated. Immunoprecipitation and lentiviral particle transfection were applied to assess the role of Gαq on PI3K activity. RESULTS: LH increased the atherosclerotic lesion area and carotid artery intima-media thickness (IMT) in OVX ApoE-/- female mice. High levels of LH attenuated vasodilation induced by Ach and inhibited NO release from HUVECs. These effects were related to the findings that LH enhanced interaction between Gαq and p110α, which subsequently inhibited PI3K activity and suppressed the phosphorylation of Akt and eNOS. CONCLUSIONS: Elevated LH promotes atherosclerosis formation in OVX ApoE-/- female mice. This effect may be mediated by inhibiting endothelial NO synthesis via PI3K/Akt signaling pathway.

16.
Aging (Albany NY) ; 11(16): 6273-6285, 2019 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-31427543

RESUMO

BACKGROUND: In our previous study, kindlin-2 promoted skin wound healing and decreased the permeability of neovascularization during angiogenesis. Herein, we explored the biological function and underlying mechanism of kindlin-2 in cutaneous melanoma. METHODS AND RESULTS: Through a series of in vitro assays, we found that high levels of kindlin-2 promoted migration and invasion of melanoma cells without influencing cell proliferation. Quantitative real-time polymerase chain reaction (qRT-PCR) and western blot analyses showed that upregulated kindlin-2 promoted the cellular epithelial-mesenchymal transition (EMT). Importantly, we found that melanoma cells overexpressing kindlin-2 promoted angiogenesis and VEGFA secretion in vitro and facilitated tumour growth and lung metastasis in vivo. To unveil the underlying mechanism, we conducted Next-generation sequencing (NGS) and differential expression analyses. Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis showed that overlapping differentially expressed genes (DEGs) were primarily enriched in the TGF-ß, mTOR and VEGF signalling pathways. Then, we confirmed that the mTOR/VEGFA pathway was activated during the process of kindlin-2-induced melanoma progression and angiogenesis. Moreover, we demonstrated that kindlin-2 was significantly overexpressed in clinical melanoma samples and that a high level of kindlin-2 predicted a poor prognosis. CONCLUSIONS: Taken together, these findings showed that kindlin-2 promotes angiogenesis and tumour progression via the mTOR/VEGFA pathway.

17.
Artigo em Inglês | MEDLINE | ID: mdl-31382434

RESUMO

This one-year longitudinal study examined trait emotional intelligence as a predictor of Internet gaming disorder (IGD). To date, only cross-sectional research has been conducted to test the protective effects of emotional intelligence against IGD tendency. Based on the Interaction of Person-Affect-Cognition-Execution (I-PACE) model, this study aimed to address the research gap by examining not only the direct effects of trait emotional intelligence, but also its indirect effects (via depressive symptoms and coping flexibility) on IGD, with both a cross-sectional and longitudinal design. The participants were 282 Chinese university students (mean age = 20.47; 39.4% males) who voluntarily completed an anonymous questionnaire at both baseline (W1) and one-year follow-up (W2). Path analysis results revealed that trait emotional intelligence had a protective but indirect effect on IGD tendency in both our cross-sectional and longitudinal data. Depression was found to have a significant, full mediating effect on the relationship between: (i) trait emotional intelligence and IGD tendency (W2) and (ii) coping flexibility and IGD tendency (W2), after adjusting for IGD tendency at the baseline (W1). Gender invariance of the path coefficient was also observed in the prospective model. This study provided longitudinal evidence to support the I-PACE model. Interventions should address both IGD and depressive symptoms, and school-based workshops to increase emotional intelligence and coping flexibility are also recommended.


Assuntos
Comportamento Aditivo/diagnóstico , Inteligência Emocional , Jogos de Vídeo , Adolescente , Adulto , Estudos Transversais , Depressão , Feminino , Humanos , Internet , Estudos Longitudinais , Masculino , Estudos Prospectivos , Inquéritos e Questionários , Adulto Jovem
18.
ACS Appl Mater Interfaces ; 11(33): 29655-29666, 2019 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-31359759

RESUMO

Ferroptosis is an iron-dependent cell death pathway that can eradicate certain apoptosis-insensitive cancer cells. The ferroptosis-inducing molecules are tailored lipid peroxides whose efficacy is compromised in hypoxic solid tumor and lack of tumor selectivity. It has been demonstrated that ascorbate (Asc) in pharmacological concentrations can selectively kill cancer cells via accumulating hydrogen peroxide (H2O2) only in tumor extracellular fluids. It was hypothesized that Asc-induced, selective enrichment of H2O2 in tumor coupled with Fe3+ codelivery could simultaneously address the above two problems via boosting the levels of hydroxyl radicals and oxygen in the tumor site to ease peroxidation initiation and propagation, respectively. The aim of this work was to synergize the action of Asc with lipid-coated calcium phosphate (CaP) hybrid nanocarrier that can concurrently load polar Fe3+ and nonpolar RSL3, a ferroptosis inducer with the mechanism of inhibiting lipid peroxide repair enzyme (GPX4). The hybrid nanocarriers showed accelerated cargo release at acidic conditions (pH 5.0). The combinational approach (Asc plus nanocarrier) produced significantly elevated levels of hydroxyl radicals, lipid peroxides, and depleted glutathione under hypoxia, which was accompanied with the strong cytotoxicity (IC50 = 1.2 ± 0.2 µM) in the model 4 T1 cells. In the 4 T1 tumor-bearing xenograft mouse model, the intravenous nanocarrier delivery plus intraperitoneal Asc administration resulted in a superior antitumor performance in terms of tumor suppression, which did not produce supplementary adverse effects to the healthy organs. This work provides a novel approach to enhance the potency of ferroptotic nanomedicine against solid tumors without inducing additional side effects.


Assuntos
Antineoplásicos/farmacologia , Peroxidação de Lipídeos/efeitos dos fármacos , Animais , Apoptose/efeitos dos fármacos , Fosfatos de Cálcio , Morte Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/fisiologia , Glutationa/metabolismo , Humanos , Peróxido de Hidrogênio/metabolismo , Peróxidos Lipídicos/química , Peróxidos Lipídicos/metabolismo , Camundongos , Espécies Reativas de Oxigênio/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto
19.
ACS Appl Mater Interfaces ; 11(27): 24377-24385, 2019 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-31195793

RESUMO

Mesoporous silica nanocarriers (MSNs) are appealing in terms of their large cavity surface area and high loading capacity, but they have been suffering from premature cargo release. Herein, we report a gated smart MSN that is sensitive to low oxygen concentration (i.e., hypoxia) via taking advantage of the superior electron-accepting ability of the azobenzene moiety. The azobenzene polymer was employed as the responsive gate-keeper that was deposited on the MSN surface, followed by coating with amphiphilic Pluronic F68 for steric stabilization. The obtained nanocarriers were less than 200 nm. The in vitro polymer degradation was spectrophotometrically witnessed via the employment of a reducing agent, namely, sodium dithionite, with a strong electron-donating ability. The hypoxia-responsive cargo release from the gated MSN was quantitatively demonstrated in breast cancer cells (MCF-7) using the fluorescence resonance energy transfer (FRET) technique where coumarin 6 and rhodamine B was selected as the FRET donor and acceptor, respectively. The FRET ratio was used as the index and decreased linearly over time under hypoxia, whereas it almost remained steady under normoxia. In addition, a model photosensitizer, namely, chlorin e6, was also loaded in the gated MSN whose toxicity under hypoxia was verified. This study developed a hypoxia-responsive MSN with the azobenzene polymer as the removable gate-keeper, which would expand the application of MSNs in pharmaceutical and biomedical areas since the low oxygen concentration is a unique trigger in many pathological conditions.

20.
J Behav Addict ; 8(2): 295-305, 2019 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-31120320

RESUMO

BACKGROUND AND AIMS: Internet gaming disorder (IGD) was proposed in Diagnostic and Statistical Manual of Mental Disorders of American Psychiatric Association as an area warranting more research attention. High prevalence of excessive Internet game use and related addictions has been reported in China, especially among youth; however, there is a lack of psychometrically and theoretically sound instruments for assessing IGD in the Chinese language. METHODS: This study aimed to examine the psychometric properties of a Chinese version of the Internet Gaming Disorder Test (IGD-20 Test) among Chinese middle school (n = 569; Mage = 13.34; 46.2% females) and university students (n = 523; Mage = 20.12; 48.4% females) samples in Beijing, China. All participants voluntarily completed an anonymous questionnaire. RESULTS: Confirmatory factor analysis results showed that the Chinese version of the IGD-20 Test had five factors (i.e., salience-tolerance, mood modification, withdrawal, conflict, and relapse). Measurement invariance was confirmed across the two samples. The test score was positively associated with the modified Young's Internet Addiction Test for gaming addiction. Concurrent validation was further demonstrated by the IGD-20 Test's positive correlation with weekly gameplay and depression symptoms. The latent profile analysis showed four different gamer classes (i.e., regular gamers, low-risk engaged gamers, high-risk engaged gamers, and probable disordered gamers), with the estimated prevalence of 2.1% of the last group. DISCUSSION AND CONCLUSION: The IGD-20 Test was applicable to Chinese youth and its Chinese version generally demonstrated good psychometric properties.


Assuntos
Comportamento Aditivo/diagnóstico , Comportamento Aditivo/psicologia , Internet , Inquéritos e Questionários/normas , Jogos de Vídeo/psicologia , Adolescente , Adulto , China , Análise Fatorial , Feminino , Humanos , Masculino , Psicometria , Reprodutibilidade dos Testes , Estudantes/psicologia , Tradução , Adulto Jovem
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