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1.
Nanotechnology ; 31(4): 045602, 2020 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-31578001

RESUMO

Exfoliation of two-dimensional (2D) materials is an issue of concern among scientific researchers. This is because many solvents such as N, N-dimethylformamide and N-methyl-2-pyrrolidone that are capable of better dispersion of 2D materials are relatively toxic and nonvolatile. This work focused on the reasonable design and mixture of two or three less toxic and volatile solvents based on Hansen solubility parameters theory to demonstrate the excellent exfoliation of 2D materials particularly reduced graphene oxide (rGO) and black phosphorus (BP). Polyvinylpyrrolidone (PVP) was introduced as a surfactant to functionalize rGO to help improve its dispersion. Results showed that PVP could effectively functionalize graphene. Few layers of rGO and BP were facilely achieved with 2-3 nm thickness from the use of the designed solvent mixtures, indicating the accomplishment of solvent mixtures in exfoliation/dispersion roles instead of the use of other toxic and nonvolatile solvents.

2.
Water Res ; 168: 115099, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31604174

RESUMO

Cow manure (CM) was added to a dynamic membrane bioreactor (DMBR) operated under anaerobic condition for enhancing food waste (FW) digestion for over 300 days with stepwise increase of organic loading rates (OLRs) from 1.07 to 11.9 g COD/L/day. At a FW/CM ratio of 3.5:1 (based on volatile solids), the mixed liquor pH was always above 8.0 and no apparent volatile fatty acids (VFAs) accumulation occurred even at the highest OLR of 11.9 g COD/L/day (hydraulic retention time as 10 days and solid retention time as 15.5 days, correspondingly), indicating a very stable operation condition which resulted in an average CH4 yield as high as 250 mL/g COD and CH4 production as high as 2.71 L CH4/L/day. The hardly biodegradable organic components, such as cellulose, hemicellulose, and lignin, were effectively degraded by 78.3%, 58.8%, and 47.5%, respectively. Significantly high anaerobic digestion reaction ratios, especially the hydrolysis ratio which is usually the limiting factor, were calculated based on experimental results. Furthermore, the high lignocellulase contents and coenzyme F420 levels, along with the decrease of cellulose crystallinity from 72.6% to 16.4% in the feedstock, provided strong evidence of an enhanced biological activity by CM addition. By high-throughput sequencing analysis, more abundant and diverse bacterial, archaeal, and fungal genera were identified from the DMBR sludge. With CM addition, the biodegradation of lignocellulose might have produced sufficient H2 and CO2 for the hydrogenotrophic methanogens such as Methanoculleus, Methanomassiliicoccus, and Methanobacterium, which were highly tolerant to ammonium inhibition, and then the elevated ammonium level would have provided high buffering capacity in the DMBR thus ensuring a stable condition for high rate FW digestion and CH4 production.


Assuntos
Microbiota , Eliminação de Resíduos , Anaerobiose , Animais , Biocombustíveis , Reatores Biológicos , Bovinos , Feminino , Alimentos , Esterco , Metano
3.
J Nanosci Nanotechnol ; 20(3): 1540-1553, 2020 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-31492317

RESUMO

To exploit new adsorbents for oil-spill cleanup, a superhydrophobic material was fabricated by hightemperature reduced graphene oxide (HRGO) coated on commercial polyurethane (PU) sponge via facile dip-coating process. Compared with chemical reagent reduced graphene oxide, the graphene showed expanded sheets and vast surface area, which ensured the water contact angle of this synthesized sponge reached 150.0±2.5°. In order to break the boundary of poor adhesion of graphene on sponge skeleton, a simple approach of sealed thermal treatment was adopted in our work. And then the high-temperature reduced graphene oxide/polyurethane sponge treated with binary flourine-free organosilanes solution showed superhydrophobicity with high water contact angle (162.4±1.0°). Silanes addition also endowed the resultant sponge with enhanced interfacial adhesion on PU skeleton owing to interconnected structure. The as-prepared sponge displayed excellent adsorption capacity, which was 48-74 times of its own weight for different organic solvents and oils, and no decrease of the adsorption capacity was observed after 20 cycles. Besides, for the very sticky oil, the Joule-heat generated in the sponge by applied voltage could reduce the viscosity of oil. With the assistance of Joule-heat, the silane modified high-temperature reduced graphene oxide/polyurethane sponge achieved effective oil-water separation and greatly speeded up the separation efficiency. Additionally, whether in various temperature or corrosive conditions, the superhydrophobicity of the sponge almost remained stable, which was promising for oil/water treatment.

4.
J Nanosci Nanotechnol ; 20(3): 1749-1755, 2020 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-31492339

RESUMO

A novel bilayer counter electrodes for Dye-sensitized Solar Cells (DSSCs) made of reduced graphene oxide (RGO) and aligned carbon nanotube (ACNT) was developed. The underlayer ACNT severs as a transition layer for RGO. The overlayer of RGO plays the role of catalytic layer. It was demonstrated that the property of graphene counter electrode was adversely affected by aggregation, by adding surfactant, the aggregation of graphene can be inhabited effectively. Moreover, the interface between the RGO and the ACNT can be optimized by surfactant functionalization of RGO. After screening, a cationic surfactant cetylpyridinium chloride (CPC) functionalized RGO, code as CPC-RGO, exhibits the best performance. Compare to the ACNT based counter electrode and other surfactant functionalized RGO/ACNT based bilayer counter electrodes, the CPC-RGO/ACNT reduced interface resistance and improved the double chemical capacitance efficiently, thus uplifting the short circuit current density and fill factor from 7.35 to 8.8 mA cm-2, and 59.87 to 62.79, respectively. Eventually, the CPC-RGO/ACNT based DSSC giving a power conversion efficiency of 3.9%, which is 1.24-fold than that of ANCT based DSSC, because of the best splay degree of CPC/RGO.

5.
Artigo em Inglês | MEDLINE | ID: mdl-31793624

RESUMO

CONTEXT: Sex hormone-binding globulin (SHBG), a homodimeric glycoprotein produced by hepatocytes has been shown to be associated with metabolic disorders. Whether circulating SHBG levels are predictive of later risk of non-alcoholic fatty liver disease (NAFLD) remains unknown. In this study, we prospectively investigated the association between SHBG and NAFLD progression through a community-based cohort comprising 3,389 Chinese adults. METHODS: NAFLD was diagnosed using abdominal ultrasonography. Serum SHBG levels were measured by chemiluminescent enzyme immunometric assay, and their relationship with NAFLD development and regression was investigated after a mean follow-up of 3.09 years using multivariable logistic regression. RESULTS: Basal SHBG was negatively associated with NAFLD development, with a fully adjusted odds ratio (OR) and its 95% confidence interval (CI) of 0.22 (0.12-0.40) (P-trend < 0.001). In contrast, basal SHBG was positively associated with NAFLD regression, with a fully adjusted OR of 4.83 (2.38-9.81) (P-trend < 0.001). Multiple-stepwise logistic regression analysis showed that SHBG concentration was an independent predictor of NAFLD development (OR, 0.28 [0.18-0.45]; P < 0.001) and regression (OR, 3.89 [2.43-6.22]; P < 0.001). In addition, the area under the receiver operating characteristic curves were 0.764 (95% CI, 0.740-0.787) and 0.762 (95% CI, 0.738-0.785) for the prediction models of NAFLD development and regression, respectively. CONCLUSIONS: Serum SHBG concentration is associated with the development and regression of NAFLD; moreover, it can be a potential biomarker for predicting NAFLD progression, and also a novel preventive and therapeutic target for NAFLD.

6.
J Econ Entomol ; 2019 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-31800055

RESUMO

The Bemisia tabaci (Gennadius) (Hemiptera: Aleyrodidae) complex comprises important pests and virus vectors in agricultural crops worldwide. In China, B. tabaci has spread to more than 20 provinces and caused severe losses of vegetables, fruits, and ornamental plants. However, B. tabaci has developed resistance to many insecticidal classes in Shandong Province, eastern China. In this study, we investigated the cryptic species, insecticide resistance and detoxifying enzymes of B. tabaci from six representative locations exhibiting severe damage in Shandong. At four of the six locations, B. tabaci Mediterranean (MED) comprised 100% of the samples collected. In a further two locations, species composition was predominantly (>94%) MED with B. tabaci Middle East-Asia Minor 1 (MEAM1), comprising a low proportion (<6%) of the samples collected. For all field populations, avermectin was the most effective insecticide against adult B. tabaci, pyriproxyfen had a significant effect on B. tabaci eggs and field populations were susceptible to pymetrozine. Six field populations of B. tabaci have developed low-to-moderate resistance to neonicotinoids. The detoxifying enzyme activity of carboxylesterase, glutathione S-transferase, and multifunctional oxidase were quantified. Multifunctional oxidase and glutathione S-transferase activity were positively correlated with insecticide resistance in several B. tabaci populations.

7.
J Environ Pathol Toxicol Oncol ; 38(3): 285-295, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31679314

RESUMO

Psoriasis is an autoregulated immune and inflammation-based skin disease affecting approximately 3-4% of the worldwide population. Pinitol, conservatively used in ayurvedic medicine, has been shown to disclose an antiinflammatory effect, hold back the T-helper cells, and postpone cardiovascular diseases. In the present study we aimed to reveal the effect of D-pinitol on imiquimod (IMQ)-induced psoriasis-like skin inflammation in a mouse model via the nuclear factor-κB (NF-κB) pathway genes. In the current study, we found that D-pinitol ameliorated the skin abrasion and abridged epithelial thickness, inflammation numbers, and collagen-occupied regions in IMQ-induced psoriasis-like mice. The same results (epithelial thickness, inflammation numbers, and collagen-occupied regions) we achieved in dorsal skin regions. In addition, D-pinitol modified the lipid profile and antioxidant enzyme levels, which means that the IMQ-induced group showed elevated malondialdehyde when compared to D-pinitol. Downregulated expression of glutathione, superoxide dismutase, and catalase in the IMQ-induced group was incomparable with D-pinitol, control, and standard group. Additionally, inflammatory and NF-kB pathway gene levels in the psoriatic mouse skin, which includes tumor necrosis factor-α, interleukin [IL]-6, IL-17A, IL-23,TRAF3, NIK, IKKα, and RelB, were dramatically increased or decreased by treatment with D-pinitol. Histological and morphometric studies disclose the efficiency of D-pinitol. Finally, we found that D-pinitol reserved the TRAF3, NIK, IKKα, and RelB in the psoriatic skin, signifying that it restrains the commencement of NF-κB signaling pathways. The present results suggest that D-pinitol could prove to have tremendous preventive potential against the treatment and prevention of inflammatory disease.


Assuntos
Anti-Inflamatórios/farmacologia , Imiquimode/imunologia , Inflamação/tratamento farmacológico , Inositol/análogos & derivados , Psoríase/tratamento farmacológico , Animais , Inflamação/induzido quimicamente , Inflamação/imunologia , Inositol/farmacologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , NF-kappa B/imunologia , Psoríase/imunologia
8.
Breast Cancer ; 2019 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-31721061

RESUMO

BACKGROUND: MicroRNAs (miRNAs) are well known to play crucial role in various types of cancers, including breast cancer (BC). METHODS: The present study aimed to investigate the expression, clinical value, and functional role of miR-302b in BC. The expression level of miR-302b was determined by quantitative real-time polymerase chain reaction (qRT-PCR). The clinical value of miR-302b in BC prognosis was calculated via Kaplan-Meier survival analysis and Cox regression analysis. Cell experiments were applied to investigate the functional role of miR-302b in BC. RESULTS: miR-302b was significantly downregulated in BC tissues and cell lines compared to the corresponding controls (all P < 0.01). Notably, the expression of miR-302b was significantly associated with lymph node metastasis and TNM stage (all P < 0.05). Patients with lower miR-302b expression had shorter survival time than those with higher miR-302b expression (log-rank P = 0.002). Furthermore, miR-302b expression and TNM stage were proven to be independent prognostic factors for BC. Overexpression of miR-302b inhibited BC cell proliferation, migration, and invasion in BT549 and MCF-7 cell lines, while silence of miR-302b exhibited an opposite effects on BC cells (all P < 0.05). RUNX2 was determined to be the target gene of miR-302b. CONCLUSIONS: The present study suggests that miR-302b functions as a tumor suppressor in BC and inhibits the tumor progression of BC via targeting RUNX2. Downregulation of miR-302b might be a significant prognostic factor for poor survival in BC patients.

9.
Sci Rep ; 9(1): 15999, 2019 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-31690791

RESUMO

As a multifunctional material, biochar is considered a potential adsorbent for removing heavy metals from wastewater. Most biochars with high adsorption capacities have been modified, but this modification is uneconomical, and modifying biochar may cause secondary pollution. Thus, it is necessary to develop an efficient biochar without modification. In this study, spent P. ostreatus substrate and spent shiitake substrate were used as the raw materials to prepare biochar. Then, the physicochemical properties of the biochars and their removal efficiencies for Pb(II) were investigated. The results showed that the physicochemical properties (e.g., large BET surface area, small pore structure and abundant functional groups) contributed to the large adsorption capacity for Pb(II); the maximum adsorption capacities were 326 mg g-1 (spent P. ostreatus substrate-derived biochar) and 398 mg g-1 (spent shiitake substrate-derived biochar), which are 1.6-10 times larger than those of other modified biochars. The Pb(II) adsorption data could be well described by the pseudo-second-order kinetic model and the Langmuir model. This study provides a new method to comprehensively utilize spent mushroom substrates for the sustainable development of the edible mushroom industry.

10.
Food Chem ; 309: 125651, 2019 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-31678674

RESUMO

The effects of low frequency magnetic field on myoglobin (Mb) oxidation stability were evaluated by treatments at 0, 3, 6, 9, 12 mT and storage for 10 h. The results showed that Mb oxidation was inhibited under all magnetic field treatments, due to the increase of total sulfhydryl and free amino groups (9 or 12 mT) from unfolding of Mb clusters (3, 9, 12 mT) as well as ß-turn and ß-sheet structures (9 or 12 mT). The unfolding also induced (i) the destruction or burial of iron porphyrin and tyrosine residues; (ii) the exposure of tryptophan; (iii) more uniform Mb particle size distribution (3, 9, 12 mT) and increased zeta potential (3, 6, 12 mT). Overall, magnetic field promoted exposed active groups as the preferred oxidation target, thus decreasing the oxidation rate of central iron atoms. It also promoted Mb stability by redistributing particle size and increasing zeta potential.

11.
Bioorg Med Chem ; : 115190, 2019 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-31744779

RESUMO

A novel series of graveolinine derivatives were synthesized and evaluated as potential anti-Alzheimer agents. Compound 5f exhibited the best inhibitory activity for acetylcholinesterase (AChE) and had surprisingly potent inhibitory activity for butyrylcholinesterase (BuChE), with IC50 values of 0.72 µM and 0.16 µM, respectively. The results from Lineweaver-Burk plot and molecular modeling study indicated non-competitive inhibition of AChE by compound 5f. In addition, these derivatives showed potent self-induced ß-amyloid (Aß) aggregation inhibition. Moreover, 5f didn't show obvious toxicity against PC12 and HepG2 cells at 50 µM. Finally, in vivo studies confirmed that 5f significantly ameliorates the cognitive performances of scopolamine-treated ICR mice. Therefore, these graveolinine derivatives should be thoroughly and systematically studied for the treatment of Alzheimer's disease.

12.
Int J Mol Sci ; 20(21)2019 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-31731556

RESUMO

The WRKY transcription factors are one of the most important plant-specific transcription factors and play vital roles in various biological processes. However, the functions of WRKY genes in wintersweet (Chimonanthus praecox) are still unknown. In this report, a group IIc WRKY gene, CpWRKY71, was isolated from wintersweet. CpWRKY71 was localized to the nucleus and possessed transcriptional activation activity. qRT-PCR (quantitative real-time PCR) analysis showed that CpWRKY71 was expressed in all tissues tested, with higher expression in flowers and senescing leaves. During the flower development, the highest expression was detected in the early-withering stage, an obvious expression of CpWRKY71 was also observed in the flower primordia differentiation and the bloom stage. Meanwhile, the expression of CpWRKY71 was influenced by various abiotic stress and hormone treatments. The expression patterns of the CpWRKY71 gene were further confirmed in CpWRKY71pro:GUS (ß-glucuronidase) plants. Heterologous overexpression of CpWRKY71 in Arabidopsis caused early flowering. Consistent with the early flowering phenotype, the expression of floral pathway integrators and floral meristem identity (FMI) genes were significantly up-regulated in transgenic plants. In addition, we also observed that the transgenic plants of CpWRKY71 exhibited precocious leaf senescence. In conclusion, our results suggested that CpWRKY71 may be involved in the regulation of flowering and leaf senescence in Arabidopsis. Our study provides a foundation for further characterization of CpWRKY genes function in wintersweet, and also enrich our knowledge of molecular mechanism about flowering and senescence in wintersweet.

13.
Pharmacology ; : 1-9, 2019 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-31671428

RESUMO

OBJECTIVES: Sepsis-induced inflammation injury and oxidative stress are well known causes of mortality. The anti-inflammatory effects of baicalin have been proposed in a mouse model of experimental sepsis. Here, we investigated its protective effects and associated mechanisms with respect to lipopolysaccharide (LPS)-induced injury in Caenorhabditis elegans. METHODS: Worms were stimulated by LPS (100 µg/mL), with baicalin (1, 10, 100 µmol/L), for 24 h. Animal survival rates and behaviors (reversal and omega turn) were then determined. Further, levels of the inflammatory cytokines interleukin 6 (IL-6), IL-1, and tumor necrosis factor (TNF)-α were detected by enzyme-linked immunosorbent assay. Western blotting was also performed to determine the protein expression levels of Toll-like receptor 4 (TLR4), nuclear factor-κB (NF-κB), Bax, and Bcl-2. The activities of malondialdehyde (MDA) and superoxide dismutase (SOD) contents were determined using corresponding kits. RESULTS: Baicalin (10, 100 µmol/L) improved LPS-stimulated C. elegans survival and rescued behavioral phenotypes. It also suppressed the oxidative stress related to LPS injury by decreasing MDA levels and increasing SOD activity. Moreover, the inflammatory response was inhibited as evidenced by decreased levels of cytokines including IL-6, IL-1, and TNF-α. In addition, baicalin treatment significantly decreased cleaved Bax levels and increased Bcl-2 expression in C. elegans treated with LPS. Simultaneously, the expression of NF-κB and TLR4 was significantly decreased. CONCLUSION: Baicalin treatment protects against LPS-induced injury by decreasing oxidative stress, repressing the inflammatory cascade, and inhibiting apoptosis.

14.
Opt Express ; 27(19): 26615-26638, 2019 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-31674539

RESUMO

Optical image tracing is one of key technologies to realize and maintain satellite-to-ground laser communication. Since machine learning has been proved to be a powerful tool for modeling nonlinear system, a model containing a preprocessing module, a CNN module (Convolutional Neural Network Module) as well as a LSTM module (Long-Short Term Neural Network Memory Module) was developed to process digital images in time series and then predict centroid positions under the influence of atmospheric turbulence. Different from most previous models composed of neural networks, some important physical situations are considered for light fields distributed on CMOS. By building and training this model, centroid positions can be predicted in real time for practical applications in laser satellite communication.

15.
J Mech Behav Biomed Mater ; 102: 103497, 2019 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-31669982

RESUMO

Carbon fiber reinforced Polyetheretherketone (PEEK) acquires mechanical strength which is close to human bone, but PEEK is inert, which can affect the bone fixation and osseointegration during dental implantation. To improve the bioactivity of PEEK, surface modification with nitric acid (HNO3) and calcium chloride (CaCl2) were utilized in this work. As the results, the hydrophilicity of the treated samples is significantly improved with the reduced roughness and attached nitro-functional group on its surface. The biological activity of CF/PEEK samples are enhanced by apatite formation evaluation soaking in simulated body fluid (SBF) in vitro after HNO3 and CaCl2 treatment. Moreover, the cytotoxicity experiments results confirm that surface treatment with HNO3 and CaCl2 is not harmful to the compatibility and safety of the cells.

16.
Biosci Rep ; 39(11)2019 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-31713581

RESUMO

Kanglaite, a type of Chinese medicine preparation, is considered a promising complementary therapy option for advanced hepatocellular carcinoma (HCC). Although an analysis of the published literature has been performed, the exact effects and safety are yet to be systematically investigated. Therefore, we conducted a wide-ranging online search of electronic databases to provide systematic conclusions; data from 31 trials with 2315 HCC patients were included. The results indicated that compared with conventional treatment (CT) alone, the combination of kanglaite with CT markedly prolonged patients' 6-month overall survival (OS, P=0.003), 12-month OS (P<0.0001), 18-month OS (P=0.003), 24-month OS (P=0.03) and 36-month OS (P=0.0006) and significantly improved the overall response rate (odds ratio (OR) = 2.57, 95% confidence interval (CI) = 2.10-3.16, P<0.00001) and disease control rate (OR = 3.10, 95% CI = 2.42-3.97, P<0.00001) of patients. The quality of life (QoL), clinical symptoms and immune function of patients were also obviously improved after combined treatment. The incidence rates of nausea and vomiting (P=0.04), hepatotoxicity (P=0.0002), leukopenia (P<0.00001), thrombocytopenia (P<0.0001), gastrointestinal side effects (P=0.01) and fever (P<0.0009) were lower in the group receiving CT and kanglaite than in the group receiving CT alone. In summary, the combination of kanglaite and CT is safe and more effective in treating HCC than is CT alone, and its application in the clinic is worth promoting.

17.
Medicine (Baltimore) ; 98(46): e17687, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31725611

RESUMO

To analyze the factors that affecting the help-seeking behavior of bipolar disorder (BD) patients by conducting interviews BD individuals in Hunan province of China.In 2015, 72,999 people from 123 counties of Hunan province of China were interviewed through multistage stratified random sampling. Twelve items of general health questionnaire (GHQ-12) and abnormal behavioral clue questionnaire were used as screening tools. The Structured Clinical Interview for Diagnostic and Statistical Manual of Mental Disorders-IV (DSM-IV) (SCID) was used as a diagnostic tool.Among the 75 BD patients, 36% (27/75) sought help. Compared with help-seekers, non-help-seekers were more likely to be older, divorced, or widowed, mostly illiterate or elementary education, family monthly income at least 3000 ¥, more physically consulted in the past year, able to effective work or study, at a stable illness status. 70.4% help-seekers firstly sought help from a medical institution. The main reasons that patients did not seek help were economic problem, did not know where to seek help, unsatisfied with medical services, afraid of mental health stigma, and other problems, such as traffic inconvenience.Non-help-seekers were faced with more difficulties in their social functions and social interactions.


Assuntos
Transtorno Bipolar/psicologia , Comportamento de Busca de Ajuda , Aceitação pelo Paciente de Cuidados de Saúde/psicologia , Adulto , Idoso , China , Análise por Conglomerados , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
18.
J Med Chem ; 2019 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-31765154

RESUMO

Diverse platinum drug candidates have been designed to improve inhibitory potency and overcome resistance for orthotopic tumor. However, the antimetastatic properties are rarely reported. We herein report that homospermidineplatin (4a), a polyamine-Pt(IV) prodrug, can potently inhibit tumor growth in situ and reverse cisplatin resistance as expected. And more importantly, 4a displays remarkably elevated antimetastatic activity in vivo (65.7%), compared to that of cisplatin (27.0%) and oxaliplatin (19.6%). The underlying molecular mechanism indicates that in addition to targeting nuclear DNA, 4a can modulate the polyamine metabolism and function in a different way from that of cisplatin. By up-regulating SSAT and PAO, 4a down-regulates the concentrations of Put, Spd and Spm, which are in favor of suppressing fast-growing tumor cells. Moreover, the p53/SSAT/ß-catenin and PAO/ROS/GSH/GSH-Px pathways are involved in the 4a-induced tumor metastasis inhibition. Our study implies a promising strategy for the design of platinum drugs to treat terminal cancer.

19.
Artigo em Inglês | MEDLINE | ID: mdl-31767528

RESUMO

OBJECTIVE: This study aimed to investigate whether air quality influences ocular comfort when wearing contact lenses and the selection tendency of myopic populations who wears contact lenses. METHODS: Questionnaires were distributed to one hundred and twenty corneal contact lens wearers to understand whether the respondents would reduce or stop the use of contact lenses according to air quality and to evaluate and compare their ocular status under different air quality conditions. RESULTS: Forty-three point eight percent of the respondents were concerned about reduced oxygen permeability of contact lenses and increased contact lens-associated complications caused by the adsorption and accumulation of haze particles on the contact lens. Thirteen point four percent of the respondents stated that they would stop using contact lenses during moderate to severe air pollution and switch to glasses. Twenty-eight point six percent of respondents remarked that they would reduce the use of contact lenses depending on the situation during moderate to severe air pollution. However, this study did not find statistically significant differences in the ocular comfort while wearing contact lenses and in the eye scores of contact lens wearers under different air quality conditions. CONCLUSION: Air quality has an impact on the selection tendency of some contact lens wearers. However, whether moderate or more severe air pollution causes ocular discomfort or contact lens-associated complications in contact lens wearers awaits further investigation.

20.
J Dent ; 91: 103231, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31712128

RESUMO

OBJECTIVES: To compare the anti-biofilm efficacy of two antimicrobial peptides (AMPs), 1018 and DJK-5, in disrupting canal wall biofilms in the isthmus, canal and dentinal tubules of single-rooted maxillary premolars. METHODS: Enterococcus faecalis single-species biofilms were formed in-situ in the root canal system of the premolars (n = 91). Confocal laser scanning microscopy, bacterial sampling, colony-forming unit counting, XTT assay, lactate dehydrogenase assay and phenol-sulphuric acid method were used to identify the anti-biofilm efficacy of both AMPs and their influence on bacterial metabolic activity. RESULTS: Both AMPs disrupted in-situ E. faecalis biofilms and altered their metabolic activity. At 20 µg/mL, the d-enantiomeric AMP DJK-5 killed 55.5 %, 57.3 % and 55.8 % of biofilm bacteria in the isthmus, canal and dentinal tubules, respectively, in 1 min. In contrast, the l-enantiomeric AMP 1018 only eradicated 25.6 %, 25.5 % and 27.5 % of biofilm bacteria in the isthmus, canal and dentinal tubules, respectively, within the same time. Anti-biofilm efficacy of the root canal irrigants tested were in the order: 6 % NaOCl > 20 µg/mL DJK-5 > 10 µg/mL DJK-5 > 20 µg/mL 1018 > 10 µg/mL 1018 > 0.9 % NaCl. CONCLUSIONS: The present results are confirmatory of previous studies, in that d-enantiomeric AMPs exhibit more potent antibacterial properties than l-enantiomeric AMPs against E. faecalis biofilms within the canal space. Nevertheless, the potency of both AMPs are concentration-dependent. Incorporation of these agents into EDTA, a non-antibacterial calcium-chelating irrigant for removal of the inorganic component of the canal space debris, does not reduce the efficacy of either AMP. CLINICAL SIGNIFICANCE: The present study provides the proof of concept that incorporation of an antimicrobial peptide into a calcium-chelating root canal irrigant enhances the disinfection of intratubular single-species biofilms during smear layer and smear plug removal.

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