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1.
Ecotoxicol Environ Saf ; 198: 110698, 2020 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-32388187

RESUMO

Di-n-butyl phthalate (DBP), the most commonly used plasticizer and typical endocrine disrupting chemicals (EDCs), has shown its characteristics of causing reproductive and developmental toxicity in males, while the neuroendocrine toxicity induced by DBP exposure in utero and the mechanism beneath still remain unclear. Here, the pregnant mice were treated with corn oil (control) or DBP at three different doses by oral gavage during gestational days (GD) 12.5-21.5. The results showed that in utero exposure to DBP induced a significant increase of gonadotropin releasing hormone (GnRH) content in serum, as well as activation and proliferation of astrocytes in the hypothalamus of offspring male mice on postnatal day (PND) 22. However, in in vitro study, mono-n-butyl phthalate (MBP), the metabolite of DBP, could not increase the release of GnRH after GnRH neurons were exposed to MBP. Further studies identified that MBP-mediated activation and proliferation of astrocytes resulted in increased secretion of prostaglandin E2 (PGE2), which might be responsible for the increased release of GnRH from GnRH neurons. This study highlights the neuroendocrine toxicity of current plasticizer DBP exposure, laying the foundation for identifying potential molecular targets for related diseases.

2.
J Cell Mol Med ; 24(9): 5224-5237, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32233073

RESUMO

Liver fibrosis, a consequence of unhealthy modern lifestyles, has a growing impact on human health, particularly in developed countries. Here, we have explored the anti-fibrotic effects of propylene glycol alginate sodium sulphate (PSS), a natural extract from brown algae, in fibrotic mice and cell models. Thus, we established bile duct ligature and carbon tetrachloride mouse models and LX-2 cell models with or without PSS treatment. Liver pathological sections and the relevant indicators in serum and liver tissues were examined. PSS prevented hepatic injury and fibrosis to a significant extent, and induced up-regulation of matrix metalloproteinase-2 and down-regulation of tissue inhibitor of metalloproteinase-1 through suppressing the transforming growth factor ß1 (TGF-ß1)/Smad pathway. PSS additionally exerted an anti-autophagy effect through suppressing the Janus kinase (JAK) 2/transducer and activator of transcription 3 (STAT3) pathway. In conclusion, PSS prevents hepatic fibrosis by suppressing inflammation, promoting extracellular matrix (ECM) decomposition and inactivating hepatic stellate cells through mechanisms involving the TGF-ß1/Smad2/3 and JAK2/STAT3 pathways in vivo and in vitro.

3.
Int Immunopharmacol ; 84: 106529, 2020 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-32344356

RESUMO

OBJECTIVE: The study was aimed to explore the hepatocellular protective functions of cafestol during hepatic ischemia-reperfusion injury and the possible mechanisms. METHODS: Ninety male Balb/c mice were randomly divided into seven groups, including normal control group, L-cafestol(20mg/kg) group, H-cafestol(40mg/kg) group, sham group, IR group, L-cafestol(20mg/kg) + IR group, H-cafestol(40mg/kg) + IR group. Serum liver enzymes (ALT, AST), inflammation mediators, proteins associated with apoptosis and autophagy, indicators linked with ERK/PPARγ pathway, and liver histopathology were measured using ELISA, qRT-PCR, immunohistochemical staining, and western blotting at 2, 8, and 24 hours after reperfusion. RESULTS: Our findings confirmed that cafestol preconditioning groups could reduce the levels of ALT and AST, alleviate liver pathological damage, suppress the release of inflammation mediators, inhibit the production of pro-apoptosis protein including caspase-3, caspase-9 and Bax, decrease the expression of autophagy-linked protein including Beclin-1 and LC3, increase anti-apoptosis protein Bcl-2, and restrain the activation of ERK and PPARγ. CONCLUSION: Cafestol preconditioning could attenuate inflammatory response, apoptosis and autophagy on hepatic ischemia reperfusion injury by suppressing ERK/PPARγ pathway.

4.
Photodiagnosis Photodyn Ther ; : 101746, 2020 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-32268216

RESUMO

BACKGROUND: 5-aminolevulinic acid photodynamic therapy (ALA-PDT) is effective in skin tumours. Studies have demonstrated that the therapy has anti-tumour immunity in squamous cell carcinoma. Exosomes play an important role in tumour microenvironment (TME) crosstalk. Nevertheless, whether exosomes mediate the ALA-PDT anti-tumour effect is unclear. This study aims to investigate whether exosomes secreted from ALA-PDT-treated squamous carcinoma cells (SCCs) demonstrate an anti-tumour effect by inducing dendritic cell (DCs) maturation. METHOD: In this study, we used electron microscopy, nanoparticle tracking analysis and western blotting to identify exosomes. Subsequently, BCA assay and fluorescence staining were used to evaluate the biological activity of exosomes. Exosomes derived from ALA-PDT-treated SCCs were incubated with SCCs, fibroblasts and immature DCs, separately. A CCK-8 kit was used to analyse the cytotoxicity of exosomes to SCCs. ELISA was utilised to analyse IL-6, VEGF, MMP-3, and TGF-ß1 secreted from fibroblasts. FACS and ELISA were used to analysed DC phenotypic maturation (CD80, MHC-II) and IL-12 secretion. RESULT: Herein we show that exosomes secreted from SCCs after ALA-PDT cannot exert cytotoxicity towards SCCs. However, exosomes derived from ALA-PDT-treated SCCs could induce DCs maturation and IL-12 secretion. Furthermore, exosomes secreted from SCCs after ALA-PDT promote the secretion of TGF-ß1 from fibroblast. CONCLUSION: In conclusion, we found that exosomes derived from ALA-PDT-treated SCCs have the ability to stimulate DC maturation and fibroblast secretion of TGF-ß1, which results in the elevation of anti-tumour immunity. These findings provide a new promising strategy of anti-tumour immune response for ALA-PDT in treating SCCs.

6.
Biol Psychiatry ; 2020 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-32111343

RESUMO

BACKGROUND: The use of psilocybin in scientific and experimental clinical contexts has triggered renewed interest in the mechanism of action of psychedelics. However, its time-dependent systems-level neurobiology remains sparsely investigated in humans. METHODS: We conducted a double-blind, randomized, counterbalanced, crossover study comprising 23 healthy human participants who received placebo and 0.2 mg/kg of psilocybin orally on 2 different test days. Participants underwent magnetic resonance imaging at 3 time points between administration and peak effects: 20 minutes, 40 minutes, and 70 minutes after administration. Resting-state functional connectivity was quantified via a data-driven global brain connectivity method and compared with cortical gene expression maps. RESULTS: Psilocybin reduced associative, but concurrently increased sensory, brain-wide connectivity. This pattern emerged over time from administration to peak effects. Furthermore, we showed that baseline connectivity is associated with the extent of psilocybin-induced changes in functional connectivity. Lastly, psilocybin-induced changes correlated in a time-dependent manner with spatial gene expression patterns of the 5-HT2A (5-hydroxytryptamine 2A) and 5-HT1A (5-hydroxytryptamine 1A) receptors. CONCLUSIONS: These results suggest that the integration of functional connectivity in sensory regions and the disintegration in associative regions may underlie the psychedelic state and pinpoint the critical role of the serotonin 2A and 1A receptor systems. Furthermore, baseline connectivity may represent a predictive marker of the magnitude of changes induced by psilocybin and may therefore contribute to a personalized medicine approach within the potential framework of psychedelic treatment.

7.
J Hepatocell Carcinoma ; 7: 19-31, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32110554

RESUMO

Objective: Shikonin is a natural product with many activities, including anti-cancer effects. Pyruvate kinase type M2 (PKM2) plays a crucial role in the growth of tumor cells. However, the effect of shikonin on PKM2 in hepatocellular carcinoma (HCC) is unclear. Methods: Cell viability, apoptosis level, glucose uptake, and lactate production were detected in HCC cells. Lentivirus-overexpressed and -shRNA of PKM2 were used to verify the key target of shikonin. A xenograft mouse model was used to detect the efficacy of shikonin and its combination with sorafenib in vivo. Results: Shikonin inhibited proliferation and glycolysis and induced apoptosis in HCC cells. Either PKM2-overexpressed or PKM2-shRNA alleviated or enhanced this effect. The results of CCK-8 showed that shikonin significantly inhibited cell viability of HCC cells. The levels of glucose uptake and lactate production were dramatically decreased by shikonin-treated. Results of flow cytometry and Western blot showed that the levels of apoptosis of HCC cells were significantly increased in a dose-dependent manner after shikonin treatment. In addition, shikonin enhanced the anti-cancer effect of sorafenib in vitro and in vivo. Our results showed that SK combined with sorafenib markedly inhibits tumor growth in HCC-transplanted nude mice compared to SK or sorafenib alone. Conclusion: By inhibiting PKM2, shikonin inhibited proliferation and glycolysis and induced cell apoptosis in HCC cells. The effect of shikonin on tumor cell proliferation, apoptosis and glycolsis will make it promising drug for HCC patients.

8.
J Exp Clin Cancer Res ; 39(1): 24, 2020 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-32000827

RESUMO

BACKGROUND: Hepatocellular carcinoma (HCC) is a common primary malignant tumor which usually progresses to an advanced stage because of late diagnosis. Sorafenib (Sora) is a first line medicine for advanced stage HCC; however, it has been faced with enormous resistance. Simvastatin (Sim) is a cholesterol-lowering drug and has been reported to inhibit tumor growth. The present study aims to determine whether Sora and Sim co-treatment can improve Sora resistance in HCC. METHODS: The HCC cell line LM3 and an established Sora-resistant LM3 cell line (LM3-SR) were used to study the relationship between Sora resistance and aerobic glycolysis. Cell proliferation, apoptosis and glycolysis levels were analyzed by western blotting, flow cytometry analysis and biomedical tests. A xenograft model was also used to examine the effect of Sim in vivo. Detailed mechanistic studies were also undertaken by the use of activators and inhibitors, and lentivirus transfections. RESULTS: Our results demonstrated that the resistance to Sora was associated with enhanced aerobic glycolysis levels. Furthermore, LM3-SR cells were more sensitive to Sim than LM3 cells, suggesting that combined treatment with both Sora and Sim could enhance the sensitivity of LM3-SR cells to Sora. This finding may be due to the suppression of the HIF-1α/PPAR-γ/PKM2 axis. CONCLUSIONS: Simvastatin can inhibit the HIF-1α/PPAR-γ/PKM2 axis, by suppressing PKM2-mediated glycolysis, resulting in decreased proliferation and increased apoptosis in HCC cells, and re-sensitizing HCC cells to Sora.

9.
Gene ; 737: 144418, 2020 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-32006597

RESUMO

Dopamine beta-hydroxylase (DßH) plays a key role in the synthesis of catecholamines (CAs) in the neuroendocrine regulatory network. The DßH gene was identified from the razor clam Sinonovacula constricta and referred to as ScDßH. The ScDßH gene is a copper type II ascorbate-dependent monooxygenase with a DOMON domain and two Cu2_monooxygen domains. ScDßH transcript expression was abundant in liver and hemolymph. During early development, ScDßH expression significantly increased at the umbo larval stage. Furthermore, the inhibitors and siRNA of DßH were screened. After challenge with DßH inhibitor, the larval metamorphosis and survival rates, and juvenile growth were obviously decreased. Under the siRNA stress, the larval metamorphosis and survival rates were also significantly decreased. Therefore, ScDßH may play an important regulating role in larval metamorphosis and juvenile growth.


Assuntos
Bivalves/crescimento & desenvolvimento , Dopamina beta-Hidroxilase/metabolismo , Larva/crescimento & desenvolvimento , Metamorfose Biológica , Sequência de Aminoácidos , Animais , Bivalves/genética , DNA Complementar/genética , Dopamina beta-Hidroxilase/química , Dopamina beta-Hidroxilase/genética , Filogenia , RNA Interferente Pequeno/genética , Homologia de Sequência de Aminoácidos
10.
J Alzheimers Dis ; 74(2): 679-690, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32083578

RESUMO

BACKGROUND: Regular aerobic exercises could improve global cognition in older adults with mild cognitive impairment (MCI), such as aerobic dance a type of commonly practiced aerobic exercises. However, its effects remain debatable in improving the cognitive function in patients with MCI. OBJECTIVE: The aim of this systematic review and meta-analysis is to evaluate the effects of aerobic dance on cognitive function among older adults with MCI. METHODS: We searched articles in the MEDLINE, PubMed, Embase, and The Cochrane Library databases from inception to 28 February 2019, with the following criteria: 1) randomized controlled trials; 2) older adults with MCI; 3) aerobic dance intervention. RESULTS: Five studies of 842 participants were identified. This meta-analysis showed that aerobic dance can significantly improve global cognition (Mini-Mental State Examination: MD = 1.43; 95% CI:[0.59, 2.27]; p = 0.0009; Alzheimer's Disease Assessment Scale-Cognitive Subscale: MD=-2.30; 95% CI:[-3.60, -1.00]; p = 0.0005), and delayed recall ability (SMD = 0.46;95% CI: [0.30, 0.62]; p < 0.00001) in older adults with MCI. In addition, have positive effects on improving executive function (Trial-Making Test A: MD = -2.37;95% CI:[-4.16, -0.58]; p = 0.010; Trial-Making Test B: MD = -16.0; 95% CI: [-30.03, -2.11]; p = 0.020) and immediate recall ability (SMD = 0.24;95% CI: [0.01, 0.46]; p = 0.04). CONCLUSION: Aerobic dance significantly improves global cognitive function and memory in older adults with MCI. In addition, it also benefits executive function. However, due to the limitations as the review states, more randomized controlled trials with better study design and larger sample sizes should be conducted in the future research to make it much clearer.

11.
Curr Diabetes Rev ; 2020 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-31916517

RESUMO

BACKGROUND: China, as the largest developing country in the world, has experienced rapid economic development during the past decades. As a side effect of the rapid growth of Chinese economy, air pollution in the form of haze, is harmful to human health. INTRODUCTION: China is also one of the countries with the highest prevalence of diabetes in Asia and has the largest burden of diabetes in the world. Recent evidence suggests a positive correlation between air pollution and the increased risk of diabetes. However, the association of haze with diabetes is still unclear. Methods Based upon literature searching and study with PubMed, the information of haze and prevalence of diabetes in different cities or provinces of China is summarized. The possible association of haze with diabetes and the perspectives of haze research particularly in prevention of haze in China are then discussed. RESULTS: The exposure of long-term air pollution such as haze reduced insulin-dependent glucose uptake, leading to insulin resistance; damage beta cell function, leading to decreased insulin secretion, and promote subcutaneous fat accumulation. Pathophysiological effects of particulate matters in diabetes through inflammation and Oxidative stress were evidenced by several epidemiological and experimental studies. CONCLUSION: A better understanding of the incidence of diabetes caused by haze exposure may facilitate policy development in air pollution prevention and intervention design in diabetes prevention. Continuous improvement in air quality may help to reduce diabetes prevalence in China.

12.
Environ Sci Technol ; 54(4): 2379-2388, 2020 02 18.
Artigo em Inglês | MEDLINE | ID: mdl-31976662

RESUMO

Hardly any study has focused on the quantitative modeling of the toxicity of anionic metal(loid)s and their mixtures in the presence of potentially competing anions. Here, we designed a univariate experiment (420 treatments) to investigate the influence of various anions (phosphate, sulfate, carbonate, and OH-) on the toxicity of single anionic metal(loid)s (arsenate, selenite, and vanadate) and a full factorial mixture experiment (196 treatments) to examine the interactions and toxicity of As-Se mixtures at 4 phosphate levels. Standard root elongation tests with wheat (Triticum aestivum) were performed. A modeling framework, resembling the biotic ligand model (BLM) for cationic metals, was developed, extended, and applied to explain anion competitions and mixture effects. Carbonate significantly alleviated the toxicity of all three metal(loid)s. The toxicity of As was significantly mitigated by phosphate, while V toxicity was significantly relieved by OH-. The BLM-like model successfully explained more than 93% of the observed variance in toxicity. With the parameters derived from single-metal(loid) exposures, the developed BLM-toxic unit model reached an overall prediction performance of 78% in modeling the toxicity of As-Se mixtures at varying phosphate levels, validating the effectiveness of the model framework. It is concluded that by taking possible anion competitions and interactions into account, the BLM-type approaches can serve as promising tools for the risk assessment of single and mixed metal(loid)s contamination.


Assuntos
Arseniatos , Vanadatos , Cátions , Ácido Selenioso , Triticum
13.
Int Urol Nephrol ; 52(1): 115-120, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31642001

RESUMO

PURPOSE: Coexistence of frailty and hemodialysis is related to higher risk of hospitalization, falls and mortality. Given the potential reversibility of frailty, reaching the epidemiology of frailty in hemodialysis is of great importance. However, estimates of the prevalence of frailty in patients on hemodialysis vary widely. We tried to synthesize the existing body of literature on the prevalence of frailty in patients on hemodialysis. METHODS: We searched Pubmed, Embase, Web of Science and Cochrane for studies of the prevalence in patients on hemodialysis. The prevalence of frailty was synthesized across eligible studies using a random-effects model. We explored potential origin of heterogeneity in the estimates by meta-regression analysis. RESULTS: Prevalence range from 6.0 to 82.0% and the pooled prevalence of frailty in patients on dialysis was 34.3% (95% confidence interval (CI) 24.5-44.1%; z = 6.87; p = 0.00). The pooled estimates of prevalence for patients aged < 55, 55-65, and ≥ 65 were 56.0% (95% CI 28.9-83.2%; z = 4.04; p = 0.00), 32.3% (95% CI 22.9-41.7%; z = 6.74; p = 0.00), and 20.3% (95% CI 7.9-32.8%; z = 3.2; p = 0.00), respectively. There were no significant relationships between frailty in hemodialysis and factors such as years of publication, sample size (continuous), sample size(> 500 vs ≤ 500), diagnostic method (the Fried Frailty vs other), country (Europe & USA vs Asia) and duration of hemodialysis. CONCLUSIONS: Frailty influences almost three in ten patients on hemodialysis. Understanding the underlying pathophysiology mechanisms and weakening the impacts of frailty in patients on hemodialysis are called on to action in the future work.

14.
Chemosphere ; 245: 125625, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31855754

RESUMO

Using Caenorhabditis elegans as an animal model, we compared the toxicity between nanopolystyrene and three metal oxide nanoparticles (NPs) (Al2O3-NPs, TiO2-NPs, and SiO2-NPs). After exposure from L1-larvae to adult day-1, nanopolystyrene (100 µg/L) reduced brood size and induced severe germline apoptosis, and nanopolystyrene (10-100 µg/L) decreased locomotion behavior, induced obvious reactive oxygen species (ROS) production, and activated noticeable mitochondrial unfolded protein response (mt UPR). Using several endpoints (lethality, development, reproduction, and/or locomotion behavior), we found that nanopolystyrene could induce more severe toxicity than SiO2-NPs, although nanopolystyrene did not cause the toxicity comparable to that in Al2O3-NPs or TiO2-NPs exposed nematodes. Our data will be useful for understanding the exposure risk of nanopolystyrene on environmental organisms. Moreover, the detected toxicity difference between nanopolystyrene and three metal oxide NPs were associated with the differences in both induction of oxidative stress and activation of mt UPR in exposed nematodes.


Assuntos
Caenorhabditis elegans/efeitos dos fármacos , Nanopartículas Metálicas/toxicidade , Nanopartículas/toxicidade , Óxidos/toxicidade , Poliestirenos/toxicidade , Animais , Apoptose/efeitos dos fármacos , Caenorhabditis elegans/metabolismo , Locomoção/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Reprodução/efeitos dos fármacos , Resposta a Proteínas não Dobradas/efeitos dos fármacos
15.
Plant Methods ; 15: 134, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31832076

RESUMO

Background: Post-transcriptional gene regulation is one of the critical layers of overall gene expression programs and microRNAs (miRNAs) play an indispensable role in this process by guiding cleavage on the messenger RNA targets. The transcriptome-wide cleavages on the target transcripts can be identified by analyzing the degradome or PARE or GMUCT libraries. However, high-throughput sequencing of PARE or degradome libraries using Illumina platform, a widely used platform, is not so straightforward. Moreover, the currently used degradome or PARE methods utilize MmeI restriction site in the 5' RNA adapter and the resulting fragments are only 20-nt long, which often poses difficulty in distinguishing between the members of the same target gene family or distinguishing miRNA biogenesis intermediates from the primary miRNA transcripts belonging to the same miRNA family. Consequently, developing a method which can generate longer fragments from the PARE or degradome libraries which can also be sequenced easily using Illumina platform is ideal. Results: In this protocol, 3' end of the 5'RNA adaptor of TruSeq small RNA library is modified by introducing EcoP15I recognition site. Correspondingly, the double-strand DNA (dsDNA) adaptor sequence is also modified to suit with the ends generated by the restriction enzyme EcoP15I. These modifications allow amplification of the degradome library by primer pairs used for small RNA library preparation, thus amenable for sequencing using Illumina platform, like small RNA library. Conclusions: Degradome library generated using this improved protocol can be sequenced easily using Illumina platform, and the resulting tag length is ~ 27-nt, which is longer than the MmeI generated fragment (20-nt) that can facilitate better accuracy in validating target transcripts belonging to the same gene family or distinguishing miRNA biogenesis intermediates of the same miRNA family. Furthermore, this improved method allows pooling and sequencing degradome libraries and small RNA libraries simultaneously using Illumina platform.

16.
Front Physiol ; 10: 1198, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31607947

RESUMO

Skeletal muscle repair and systemic inflammation/immune responses are linked to endoplasmic reticulum stress (ER stress) pathways in myopathic muscle, and muscle cells play an active role in muscular immune reactions by exhibiting immunological characteristics under persistent proinflammation stimuli. Whether ER stress affects the intrinsic immunological capacities of myocytes in the inflammatory milieu, as it does to immune cells, and which arms of the unfolded protein response (UPR) mainly participate in these processes remain mostly unknown. We investigated this issue and showed that inflammatory stimuli can induce the activation of the protein kinase R (PKR)-like endoplasmic reticulum kinase (PERK) and inositol-requiring enzyme 1α (IRE1α) arms of the UPR in myocytes both in vivo and in vitro. UPR stressor administration reversed the increased IFN-γ-induced expression of the MHC-II molecule H2-Ea, the MHC-I molecule H-2K b , toll-like receptor 3 (TLR3) and some proinflammatory myokines in differentiated primary myotubes in vitro. However, further IRE1α inhibition thoroughly corrected the trend in the UPR stressor-triggered suppression of immunobiological molecules. In IFN-γ-treated myotubes, dramatic p38 MAPK activation was observed under IRE1α inhibitory conditions, and the pharmacological inhibition of p38 reversed the immune molecule upregulation induced by IRE1α inhibition. In parallel, our coculturing system verified that the ovalbumin (OVA) antigen presentation ability of inflamed myotubes to OT-I T cells was enhanced by IRE1α inhibition, but was attenuated by further p38 inhibition. Thus, the present findings demonstrated that p38 MAPK contributes greatly to IRE1α arm-dependent immunobiological suppression in myocytes under inflammatory stress conditions.

17.
Photodiagnosis Photodyn Ther ; 28: 330-337, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31618677

RESUMO

The emergence of drug-resistant bacteria, such as methicillin-resistant Staphylococcus aureus (MRSA), has brought great difficulties to clinical treatment. Antibacterial photodynamic therapy (aPDT) is a new non-antibiotic treatment strategy for a variety of drug-resistant bacteria. However, there are few studies on the antimicrobial mechanism of a PDT mediated by 5-aminolevulinic acid (ALA-PDT) for MRSA. In this study, we observed the bactericidal effect of ALA-PDT on MRSA. We found that ALA-PDT had the strongest bactericidal effect when ALA was at 0.05 mM, and the bactericidal activity of aPDT increased with the increase of light dose. MRSA was almost completely eliminated at 0.05 mM and 384 Jcm-2. In addition, the bactericidal morphology was also observed under a fluorescence microscope using a LIVE/DEAD® BacLight™ Bacterial Viability Kit and an electron microscope. It was also found that proteins and DNA were damaged by ALA-PDT. Finally, the transcription level of the specific gene of MRSA, nuc, was decreased by 0.74-fold (P < 0.05) after ALA-PDT treatment by qRT-PCR analysis. The findings suggest that ALA-PDT can effectively inhibit MRSA by damaging cell membrane, cytoplasm, proteins and nucleic acid.

18.
Appl Opt ; 58(23): 6244-6250, 2019 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-31503766

RESUMO

This paper presents the gradient-guided image super-resolution reconstruction for terahertz imaging to improve the image quality, taking advantage of super-resolution reconstruction based on adaptive super-pixel gradient field transform. Moreover, spatial entropy-based enhancement and a bilateral filter are introduced to ensure better performance of the reconstruction. Furthermore, we compare the performance of reconstruction operated on terahertz images with frequencies of 0.1 THz, 0.3 THz, 0.5 THz, and 0.7 THz. Experimental results demonstrate that this method successfully improves the image quality and reconstruct high-resolution images from low-resolution images with the peak signal-to-noise ratio and structural similarity index improved. In addition, the signal frequency and intensity are demonstrated to affect the performance of reconstruction.

19.
Sensors (Basel) ; 19(18)2019 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-31505866

RESUMO

The privacy and security of the Internet of Things (IoT) are emerging as popular issues in the IoT. At present, there exist several pieces of research on network analysis on the IoT network, and malicious network analysis may threaten the privacy and security of the leader in the IoT networks. With this in mind, we focus on how to avoid malicious network analysis by modifying the topology of the IoT network and we choose closeness centrality as the network analysis tool. This paper makes three key contributions toward this problem: (1) An optimization problem of removing k edges to minimize (maximize) the closeness value (rank) of the leader; (2) A greedy (greedy and simulated annealing) algorithm to solve the closeness value (rank) case of the proposed optimization problem in polynomial time; and (3)UpdateCloseness (FastTopRank)-algorithm for computing closeness value (rank) efficiently. Experimental results prove the efficiency of our pruning algorithms and show that our heuristic algorithms can obtain accurate solutions compared with the optimal solution (the approximation ratio in the worst case is 0.85) and outperform the solutions obtained by other baseline algorithms (e.g., choose k edges with the highest degree sum).

20.
Nanotoxicology ; 13(10): 1362-1379, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31462114

RESUMO

Carbon nanoparticles (CNP) are generated by incomplete combustion of diesel engines. Several epidemiological studies associated higher susceptibility to particulate matter related adverse respiratory outcomes with preexisting conditions like chronic bronchitis (CB). Therefore, we compared the effect of CNP exposure on primary bronchial epithelial cells (PBEC) developed in air-liquid interface (ALI) models of normal versus CB-like-mucosa.PBEC cultured at ALI represented normal mucosa (PBEC-ALI). To develop CB-like-mucosa (PBEC-ALI/CB), 1 ng/ml interleukin-13 was added to the basal media of PBEC-ALI culturing. PBEC-ALI and PBEC-ALI/CB were exposed to sham or to aerosolized CNP using XposeALI® system. Protein levels of CXCL-8 and MMP-9 were measured in the basal media using ELISA. Transcript expression of pro-inflammatory (CXCL8, IL6, TNF, NFKB), oxidative stress (HMOX1, SOD3, GSTA1, GPx), tissue injury/repair (MMP9/TIMP1) and bronchial cell type markers (MUC5AC, CC10) were assessed using qRT-PCR.Increased secretion of CXCL-8 and MMP-9 markers was detected 24 h post-exposure in both PBEC-ALI and PBEC-ALI/CB with more pronounced effect in the later. Pro-inflammatory and tissue injury markers were increased at both 6 h and 24 h post-exposure in PBEC-ALI/CB. Oxidative stress markers exhibited similar responses at 6 h and 24 h post-exposure in PBEC-ALI/CB. The club cell specific marker CC10 was increased by 300 fold in PBEC-ALI/CB and 20 fold in PBEC-ALI following CNP exposure.Our data indicates an earlier and stronger reaction of pro-inflammatory, oxidative stress and tissue injury markers in PBEC-ALI/CB models compared to PBEC-ALI models following CNP exposure. The findings may provide insight into the plausible mechanisms of higher susceptibility among predisposed individuals to nanoparticle exposure.

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