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1.
EMBO J ; 42(7): e111112, 2023 04 03.
Artigo em Inglês | MEDLINE | ID: mdl-36799040

RESUMO

Brain metastasis, most commonly originating from lung cancer, increases cancer morbidity and mortality. Although metastatic colonization is the rate-limiting and most complex step of the metastatic cascade, the underlying mechanisms are poorly understood. Here, in vivo genome-wide CRISPR-Cas9 screening revealed that loss of interferon-induced transmembrane protein 1 (IFITM1) promotes brain colonization of human lung cancer cells. Incipient brain metastatic cancer cells with high expression of IFITM1 secrete microglia-activating complement component 3 and enhance the cytolytic activity of CD8+ T cells by increasing the expression and membrane localization of major histocompatibility complex class I. After activation, microglia (of the innate immune system) and cytotoxic CD8+ T lymphocytes (of the adaptive immune system) were found to jointly eliminate cancer cells by releasing interferon-gamma and inducing phagocytosis and T-cell-mediated killing. In human cancer clinical trials, immune checkpoint blockade therapy response was significantly correlated with IFITM1 expression, and IFITM1 enhanced the brain metastasis suppression efficacy of PD-1 blockade in mice. Our results exemplify a novel mechanism through which metastatic cancer cells overcome the innate and adaptive immune responses to colonize the brain, and suggest that a combination therapy increasing IFITM1 expression in metastatic cells with PD-1 blockade may be a promising strategy to reduce metastasis.


Assuntos
Neoplasias Encefálicas , Neoplasias Pulmonares , Humanos , Animais , Camundongos , Linfócitos T CD8-Positivos , Receptor de Morte Celular Programada 1 , Neoplasias Pulmonares/patologia , Encéfalo/patologia
3.
Front Chem ; 10: 971859, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36157033

RESUMO

Ternary composite with great modulation of electron transfers has attracted a lot of attention from the field of high-performance room-temperature (RT) gas sensing. Herein, walnut-like WO3-Ni-graphene ternary composites were successfully synthesized by the hydrothermal method for formaldehyde (HCHO) sensing at RT. The structural and morphological analyses were carried out by scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), Raman spectroscopy, and X-ray photoelectron spectroscopy (XPS). SEM and TEM studies confirmed that walnut-like WO3 nanostructures with an average size of 53 ± 23 nm were functionalized. The Raman and XPS results revealed that, due to the deformation of the O-W-O lattice, surface oxygen vacancies Ov and surface-adsorbed oxygen species Oc were present. The gas-sensing measurement shows that the response of the WO3-Ni-Gr composite (86.8%) was higher than that of the Ni-Gr composite (22.7%) for 500 ppm HCHO at RT. Gas-sensing enhancement can be attributed to a p-n heterojunction formation between WO3 and Ni-Gr, Oc, spill-over effect of Ni decoration, and a special walnut-like structure. Moreover, long term stability (%R = 61.41 ± 1.66) for 30 days and high selectivity in the presence of other gases against HCHO suggested that the proposed sensor could be an ideal candidate for future commercial HCHO-sensing in a real environment.

4.
Arch Virol ; 167(12): 2519-2528, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36083350

RESUMO

The wide spread of coronavirus disease 2019 (COVID-19) has significantly threatened public health. Human herd immunity induced by vaccination is essential to fight the epidemic. Therefore, highly immunogenic and safe vaccines are necessary to control SARS-CoV-2, whose S protein is the antigenic determinant responsible for eliciting antibodies that prevent viral entry and fusion. In this study, we developed a SARS-CoV-2 DNA vaccine expressing the S protein, named pVAX-S-OP, which was optimized according to the human-origin codon preference and using polyinosinic-polycytidylic acid as an adjuvant. pVAX-S-OP induced specific antibodies and neutralizing antibodies in BALB/c and hACE2 transgenic mice. Furthermore, we observed 1.43-fold higher antibody titers in mice receiving pVAX-S-OP plus adjuvant than in those receiving pVAX-S-OP alone. Interferon gamma production in the pVAX-S-OP-immunized group was 1.58 times (CD3+CD4+IFN-gamma+) and 2.29 times (CD3+CD8+IFN-gamma+) lower than that in the pVAX-S-OP plus adjuvant group but higher than that in the control group. The pVAX-S-OP vaccine was also observed to stimulate a Th1-type immune response. When, hACE2 transgenic mice were challenged with SARS-CoV-2, qPCR detection of N and E genes showed that the viral RNA loads in pVAX-S-OP-immunized mice lung tissues were 104 times and 106 times lower than those of the PBS control group, which shows that the vaccine could reduce the amount of live virus in the lungs of hACE2 mice. In addition, pathological sections showed less lung damage in the pVAX-S-OP-immunized group. Taken together, our results demonstrated that pVAX-S-OP has significant immunogenicity, which provides support for developing SARS-CoV-2 DNA candidate vaccines.


Assuntos
COVID-19 , Vacinas de DNA , Animais , Humanos , Camundongos , Adjuvantes Imunológicos , Anticorpos Neutralizantes , Anticorpos Antivirais , COVID-19/prevenção & controle , Imunidade Celular , Camundongos Transgênicos , SARS-CoV-2/genética , Glicoproteína da Espícula de Coronavírus/genética , Vacinas de DNA/genética
5.
Front Physiol ; 13: 865627, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35655959

RESUMO

Circadian control allows organisms to anticipate and adapt to environmental changes through changes in physiology and behavior. The circadian system timing is entrained by cues, such as light, food, and temperature. An ambient temperature dramatically impacts the sleep-wake cycle and metabolic rhythmicity. As endotherms, mammals rely on tissues such as the liver to provide fuel for thermogenesis to maintain body temperature. The adaptive response of the circadian rhythm of liver metabolism to chronic cold exposure remains largely unexplored. Here, we investigated the circadian rhythm adaptation of hepatic metabolism in response to environmental cold stress using a mouse model of chronic cold exposure. We analyzed metabolites and transcripts of mouse livers at 24 h and found that long-term low-temperature exposure resulted in a synergistic and phase synchronization of transcriptional rhythms of many genes associated with metabolic pathways. Notably, transcription peaked in the early light phase when the body temperature was relatively low. Our results suggest that chronic cold does not alter the rhythmic expression of essential core clock genes in the liver, so the rewiring of clock control gene expression is another mechanism that optimizes the circadian rhythm of liver metabolism to meet the energy requirements of animal thermogenesis.

6.
Am J Reprod Immunol ; 88(1): e13579, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35594386

RESUMO

PROBLEM: Ghrelin has been thought of as a potential link between energy homeostasis and fertility. The aim of this study was to evaluate levels of ghrelin in obese and non-obese systemic lupus erythematosus (SLE) patients, and to reveal a possible association between ghrelin and Anti-Mullerian hormone (AMH) in SLE patients. METHOD OF STUDY: One hundred SLE patients (50 obese and 50 non-obese subjects) at childbearing age and 100 age-matched healthy controls (50 obese and 50 non-obese subjects) were included. Ghrelin and leptin were examined by enzyme-linked immunosorbent assay. AMH was tested through electrochemiluminescence. Demographics, clinical and laboratory indicators were obtained from medical records. RESULTS: Ghrelin levels were significantly lower in obese SLE patients than non-obese SLE patients (P = .000) and obese controls (P = .002). Non-obese SLE patients and non-obese controls had similar ghrelin levels. Ghrelin levels were correlated positively with AMH (r = .2683, P = .0070) in SLE patients. And ghrelin were negatively associated with leptin (r = -.1969, P = .0496) and BMI (r = - .2401, P = .0161). CONCLUSION: Our results provide evidence for a potential relationship between ghrelin and AMH in SLE patients, indicating that ghrelin may play a part in energy homeostasis and ovarian damage of SLE patients.


Assuntos
Lúpus Eritematoso Sistêmico , Reserva Ovariana , Hormônio Antimülleriano , Estudos de Casos e Controles , China , Feminino , Grelina , Humanos , Leptina , Obesidade
7.
Front Chem ; 9: 742488, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34616714

RESUMO

As formaldehyde is an extremely toxic volatile organic pollutant, a highly sensitive and selective gas sensor for low-concentration formaldehyde monitoring is of great importance. Herein, metal-organic framework (MOF) derived Pd/PdO@ZnO porous nanostructures were synthesized through hydrothermal method followed by calcination processes. Specifically, porous Pd/PdO@ZnO nanomaterials with large surfaces were synthesized using MOFs as sacrificial templates. During the calcination procedure, an optimized temperature of 500°C was used to form a stable structure. More importantly, intensive PdO@ZnO inside the material and composite interface provides lots of p-n heterojunction to efficiently manipulate room temperature sensing performance. As the height of the energy barrier at the junction of PdO@ZnO exponentially influences the sensor resistance, the Pd/PdO@ZnO nanomaterials exhibit high sensitivity (38.57% for 100 ppm) at room temperature for 1-ppm formaldehyde with satisfactory selectivity towards (ammonia, acetone, methanol, and IPA). Besides, due to the catalytic effect of Pd and PdO, the adsorption and desorption of the gas molecules are accelerated, and the response and recovery time is as small as 256 and 264 s, respectively. Therefore, this MOF-driven strategy can prepare metal oxide composites with high surface area, well-defined morphology, and satisfactory room-temperature formaldehyde gas sensing performance for indoor air quality control.

8.
J Nanosci Nanotechnol ; 21(10): 5241-5246, 2021 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-33875113

RESUMO

In this work, we describe the principle and operation of a bubble-liquid membrane reactor, and use of the reactor to prepare spherical calcium carbonate nanoparticles. The products were characterized by X-ray diffraction, Fourier transform infrared spectroscopy, scanning electron microscopy, and laser particle size analysis. The effects of additives to control crystal morphology, coating agents, and the stirring speed of the bubble-liquid membrane reactor were investigated. Spherical calcium carbonate nanoparticles with uniform dispersion and no agglomeration were obtained when a disodium hydrogen phosphate/ethylenediaminetetraacetic acid disodium salt mixture (1:1 mass ratio) was used as the additive, oleic acid was used as the coating agent (1.5 wt%), and the stirring speed was 5000-6000 r/min. The results indicate that the bubble-liquid membrane reactor may be suitable for continuous industrial production of calcium carbonate nanoparticles.


Assuntos
Carbonato de Cálcio , Nanopartículas , Microscopia Eletrônica de Varredura , Tamanho da Partícula , Espectroscopia de Infravermelho com Transformada de Fourier , Difração de Raios X
9.
Front Hum Neurosci ; 15: 739333, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34975431

RESUMO

Research on light modulation has typically examined the wavelength, intensity, and exposure time of light, and measured rhythm, sleep, and cognitive ability to evaluate the regulatory effects of light variables on physiological and cognitive functions. Although the frequency of light is one of the main dimensions of light, few studies have attempted to manipulate it to test the effect on brain activation and performance. Recently, 40-Hz light stimulation has been proven to significantly alleviate deficits in gamma oscillation of the hippocampus caused by Alzheimer's disease. Although this oscillation is one of the key functional characteristics of performing memory tasks in healthy people, there is no evidence that 40-Hz blue light exposure can effectively regulate brain activities related to complex cognitive tasks. In the current study, we examined the difference in the effects of 40-Hz light or 0-Hz light exposure on brain activation and functional connectivity during a recognition memory task. Through joint augmentation of visual area activation, 40-Hz light enhanced brain areas mostly in the limbic system that are related to memory, such as the hippocampus and thalamus. Conversely, 0-Hz light enhanced brain areas mostly in the prefrontal cortex. Additionally, functional connection analysis, with the hippocampus as the seed point, showed that 40-Hz light enhanced connection with the superior parietal lobe and reduced the connection with the default network. These results indicate that light at a frequency of 40 Hz can change the activity and functional connection of memory-related core brain areas. They also indicate that in the use of light to regulate cognitive functions, its frequency characteristics merit attention.

10.
Mater Sci Eng C Mater Biol Appl ; 118: 111432, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33255026

RESUMO

Nowadays featuring outstanding eco-friendliness, the phytochemical fabrication method of nanostructures is very popular. Here, we propose to utilize the Astragalus membranaceus extract as the reducing and capping agent to stabilize the metal and to avoid the aggregations of nanoparticles during ZnO nanoflowers synthesis procedure. As a result, the whole fabrication procedure was highly efficient and cost-effective without requiring a special environment of high pressure or elevated temperature and without chemical hazards used or produced. After the fabrication, detailed characterization about material morphology and crystal structure was carried out, including scanning electron microscopy (SEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and Fourier transform infrared spectroscope (FTIR). Moreover, the ZnO nanoflowers demonstrated distinctive antibacterial, antioxidant and electrochemical sensing effect. Specifically, ZnO nanoflowers had an antibacterial inhibition zone of 19(±0.7) and 15(±0.8) mm in diameter against the concentration of 50 µL (1 mg/mL) Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus), which is greatly improved compared to the reference drug (Kanamycin). Besides, antioxidant activity was also tested using H2O2 free radical scavenging assay and 60% 2,2-diphenyl-1-picrylhydrazyl (DPPH) inhibition of 0.5 mg/mL was reported. Finally, controlled by the diffusion process during the charge transfer procedure, 4-nitorphenol was dramatically reduced and a limit of detection of 0.08 µM by ZnO nanoflowers modified electrode was observed during the cyclic voltammetry (CV) experiment. Because the phenolic compounds originating from Astragalus membranaceus helped to facilitate the electron transfer, the limit of detection was lower compared to other materials, such as copper oxide nanoparticles (Cu2O-NPs), silicon dioxide/silver nanoparticles (SiO2/Ag-NPs), zinc oxide nanoparticles (ZnO-NPs), activated carbon (AC) and cobalt oxide nanocubes (Co3O4). Therefore, featuring easy operation, low-cost and eco-friendliness, our proposed ZnO nanoflowers fabrication method will have a great potential in biomedical and electro-catalytic fields.


Assuntos
Nanopartículas Metálicas , Óxido de Zinco , Antibacterianos/farmacologia , Antioxidantes/farmacologia , Astragalus propinquus , Biomimética , Escherichia coli , Testes de Sensibilidade Microbiana , Dióxido de Silício , Prata , Espectroscopia de Infravermelho com Transformada de Fourier , Staphylococcus aureus , Difração de Raios X
11.
Front Pharmacol ; 11: 573074, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33381029

RESUMO

The circadian clock plays a key role in our daily physiology and metabolism. Alcohol consumption disrupts the circadian rhythm of metabolic genes in the liver; however, the potential contribution of circadian clock modulation to alcoholic liver disease (ALD) is unknown. We identified a novel liver protective agent, physcion, which can alleviate fat accumulation and inflammation in ALD mice via reprogramming the hepatic circadian clock. The model of alcoholic hepatitis was established by intragastrically administering ethanol. In vitro, physcion was investigated by treating HepG2 cells with ethanol. The role of circadian clock in Physcion caused liver protection was tested by knocking down the core circadian gene Bmal1. Physcion application caused reduced lipogenesis and alleviated inflammation in alcohol-induced mice. In alcoholic hepatosteatosis models, physcion upregulated the core circadian genes. And the circadian misalignment triggered by ethanol was efficiently reversed by physcion. Physcion attenuated lipogenesis via reprogramming the circadian clock in HepG2 cells. Suppression of Bmal1 by RNA interference abolished the protective of physcion. In addition, Physcion binds to the active pocket of BMAL1 and promotes its expression. The study identified the novel liver protective effects of physcion on alcohol-induced liver injury, and modulation of the core circadian clock regulators contributes to ALD alleviation. More importantly, strategies targeting the circadian machinery, for example, Bmal1, may prove to be beneficial treatment options for this condition.

12.
Front Physiol ; 11: 294, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32390857

RESUMO

Alzheimer's disease (AD) patients often exhibit perturbed circadian rhythm with fragmented sleep before disease onset. This study was designed to evaluate the effect of a 40-Hz light flicker on circadian rhythm in an AD mouse model (APP/PS1). Locomotor rhythms recordings were conducted to examine the circadian clock rhythm in APP/PS1 mice. Molecular biology analyses, including western blot and real-time qPCR assays, were conducted to assess the changes in circadian locomotor output cycles kaput (CLOCK), brain and muscle arnt-like protein-1 (BMAL1), and period 2 (PER2). In addition to determining the direct effect of a 40-Hz light flicker on hypothalamic central clock, whole-cell voltage-clamp electrophysiology was employed to record individual neurons of suprachiasmatic nucleus (SCN) sections. The results reported herein demonstrate that a 40-Hz light flicker relieves circadian rhythm disorders in APP/PS1 mice and returns the expression levels of key players in the central circadian clock, including Clock, Bmal1, and Per2, to baseline. Moreover, the frequency of spontaneous inhibitory postsynaptic currents (sIPSCs) in SCN neurons is significantly lower in APP/PS1 mice than in the control, and the amplitude of sIPSCs is decreased. Exposure to a 40-Hz light flicker significantly increases the sIPSC frequency in SCN neurons of APP/PS1 mice, with little effect on the amplitude. However, the frequency and amplitude of spontaneous excitatory postsynaptic currents (sEPSCs) are both unaffected by a 40-Hz light flicker. The data suggest that a 40-Hz light flicker can ameliorate AD-associated circadian rhythm disorders, presenting a new type of therapeutic treatment for rhythm disorders caused by AD.

13.
Front Pharmacol ; 11: 355, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32269528

RESUMO

Sirtuin 1 (SIRT1) is a protein deacetylase with important cellular functions, as it regulates numerous processes, including the circadian rhythm in peripheral tissues. Efforts are ongoing to reveal how Sirt1 can be used to treat diseases, such as alcoholic liver disease (ALD), Alzheimer's disease, and liver fibrosis. We have recently shown that noninvasive exposure to 40-Hz light flicker activates hypothalamic SIRT1 gene expression, thereby regulating the central circadian clock. This study investigated the effects of 40-Hz light flicker in a mouse model of ALD. RNA sequencing (RNA-seq) analysis was performed to explore the potential pathways affected by 40-Hz light flicker. We found that 40-Hz light flicker significantly decreased the acute ethanol-induced increases in serum alanine aminotransferase (ALT) and serum triglyceride (TG) levels and reduced fat-droplet accumulation in mouse livers. Additionally, 40-Hz light flicker significantly suppressed ethanol-induced increases in sterol regulatory element binding protein 1 (SREBP-1) and fatty acid synthase (Fasn) levels. Furthermore, the ethanol induced significant decreases in both Sirt1 levels and phosphorylation of adenosine monophosphate-activated protein kinase subunit (AMPKα), compared with those in the control group. Strikingly, pretreatment with 40-Hz light flicker ameliorated such ethanol-induced decreases in SIRT1 levels and AMPKα phosphorylation. In addition, ethanol-induced increases in levels of brain and muscle arnt-like protein-1 (BMAL1), circadian locomotor output cycles kaput (CLOCK), and period 2 (PER2) were reversed by 40-Hz light flicker. RNA-seq analysis revealed significant differences in expression of genes related to the AMPK signalling. Moreover, ethanol consumption altered mRNA levels of Sirt1 and circadian genes in the suprachiasmatic nucleus (SCN), indicating that ethanol influenced central pacemaker genes; however, 40-Hz light flicker reversed these ethanol-induced changes. Taken together, our findings demonstrate that 40-Hz light flicker rapidly influence the SCN and exhibits inhibitory properties on hepatic lipogenesis, indicating that 40-Hz light flicker has therapeutic potential for preventing alcoholic liver steatosis.

14.
J Cell Mol Med ; 24(6): 3469-3480, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32052937

RESUMO

Primary open-angle glaucoma (POAG) is the second leading cause of irreversible blindness worldwide. Increased endothelin-1 (ET-1) has been observed in aqueous humour (AH) of POAG patients, resulting in an increase in the out-flow resistance of the AH. However, the underlining mechanisms remain elusive. Using established in vivo and in vitro POAG models, we demonstrated that water channel Aquaporin 1 (AQP1) is down-regulated in trabecular meshwork (TM) cells upon ET-1 exposure, which causes a series of glaucomatous changes, including actin fibre reorganization, collagen production, extracellular matrix deposition and contractility alteration of TM cells. Ectopic expression of AQP1 can reverse ET-1-induced TM tissue remodelling, which requires the presence of ß-catenin. More importantly, we found that ET-1-induced AQP1 suppression is mediated by ATF4, a transcription factor of the unfolded protein response, which binds to the promoter of AQP1 and negatively regulates AQP1 transcription. Thus, we discovered a novel function of ATF4 in controlling the process of TM remodelling in ET-1-induced POAG through transcription suppression of AQP1. Our findings also detail a novel pathological mechanism and a potential therapeutic target for POAG.


Assuntos
Fator 4 Ativador da Transcrição/metabolismo , Aquaporina 1/metabolismo , Endotelinas/metabolismo , Glaucoma de Ângulo Aberto/patologia , Malha Trabecular/metabolismo , Animais , Humor Aquoso/química , Cegueira/patologia , Linhagem Celular , Modelos Animais de Doenças , Regulação para Baixo , Regulação da Expressão Gênica/genética , Humanos , Coelhos , Transcrição Gênica/genética
15.
J Microencapsul ; 36(6): 552-565, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31403342

RESUMO

Taxane-based chemotherapy-loaded drug delivery systems have great potential for cancer treatment. The docetaxel (DTX)-loaded PAMAM-based poly (γ-benzyl-l-glutamate)-b-d-α-tocopheryl polyethylene glycol 1000 succinate (PAM-PBLG-b-TPGS) nanoparticles and the docetaxel (DTX)-loaded PAMAM-based poly (γ-benzyl-l-glutamate) (PAM-PBLG) nanoparticles were designed using a modified nanoprecipitation method. The particle size, encapsulation efficiency (EE), and in vitro release characteristics of the nanoparticles were tested. The effects of the two nanoparticles on the cellular uptake and cell viability on human cervical cancer cell line Hela and the human breast cancer cell line MCF-7 were compared. Furthermore, their antitumor efficiency was evaluated through in vivo tumour growth experiment in comparison with free DTX. PAM-PBLG-b-TPGS nanoparticles displayed high EE, smaller diameter, and a nice releasing profile. Besides, based on the high EE and 'self-controlled' drug release of the DTX-loaded PAM-PBLG-b-TPGS nanoparticles, they exhibited stronger cytotoxicity (lower survival rate) and higher uptake rate than DTX-loaded PAM-PBLG nanoparticles in Hela cells and MCF-7 cells. Furthermore, compared with DTX-loaded PAM-PBLG nanoparticles and free DTX, DTX-loaded PAM-PBLG-b-TPGS nanoparticles produced a potent anti-tumour effect. Thus, the DTX-loaded PAM-PBLG-b-TPGS nanoparticles provide a novel attractive nanocarrier for the DTX delivery of chemotherapy to human breast cancer cells and human cervical cancer cells.


Assuntos
Antineoplásicos/administração & dosagem , Neoplasias da Mama/tratamento farmacológico , Docetaxel/administração & dosagem , Portadores de Fármacos/química , Neoplasias do Colo do Útero/tratamento farmacológico , Vitamina E/química , Animais , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Neoplasias da Mama/patologia , Dendrímeros/química , Docetaxel/farmacologia , Docetaxel/uso terapêutico , Liberação Controlada de Fármacos , Feminino , Células HeLa , Humanos , Células MCF-7 , Camundongos Endogâmicos BALB C , Camundongos Nus , Neoplasias do Colo do Útero/patologia
16.
Biol Pharm Bull ; 42(2): 158-163, 2019 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-30429411

RESUMO

Ghrelin is a circulating peptide hormone, which involved in promoting feeding and regulating energy metabolism in human and rodents. Abnormal synovial hyperplasia is the most important pathologic hallmark of rheumatoid arthritis (RA), which is characterised by tumor-like expansion. Existing studies indicated that there may exist some relation between the decreased ghrelin and the abnormally proliferating synovial cells in RA. Therefore, the aim of this study is to explore the apoptotic effects of ghrelin on MH7A synovial cells in vitro. 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay was used to evaluate the effects of ghrelin on the viability of MH7A cells. Terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate-biotin nick-end labeling (TUNEL) and flow cytometry were used to test the apoptotic effects of ghrelin. At last, Western blot and real-time PCR were performed to explore the expression of caspases-8, -9, and -3 after the treatment of ghrelin. MTT experiments showed that ghrelin could inhibit viability of MH7A cells. The results of flow cytometry and TUNEL showed that ghrelin could induce apoptosis of MH7A synovial cells. Western blot showed that expression of cleaved-caspases-8, -9, and -3 were increased in ghrelin stimulation group compared with the control group, while expression of pro-caspases-8, -9, and -3 had no significant difference. In mRNA levels, ghrelin can decrease pro-caspases-8, -9, and -3 mRNA expression, which confirmed the results of protein levels. Then these apoptotic effects were significantly reversed by [D-Lys3] GHRP-6 (ghrelin receptor antagonist). This study found that ghrelin can induce apoptosis of MH7A cells through caspase signaling pathways.


Assuntos
Artrite Reumatoide/tratamento farmacológico , Grelina/farmacologia , Sinoviócitos/efeitos dos fármacos , Apoptose/efeitos dos fármacos , Artrite Reumatoide/metabolismo , Artrite Reumatoide/patologia , Caspases/metabolismo , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Fibroblastos/efeitos dos fármacos , Fibroblastos/metabolismo , Fibroblastos/patologia , Humanos , Lipopolissacarídeos/farmacologia , Sinoviócitos/metabolismo , Sinoviócitos/patologia
17.
Appl Opt ; 57(16): 4701-4706, 2018 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-29877353

RESUMO

We present what we believe is a novel directional coupler based on an elliptic cylindrical nanowire hybrid plasmonic waveguide. Using the finite element method, the electric field distributions of y-polarized symmetric and antisymmetric modes of the coupler are compared, and the coupling and transmission characteristics are analyzed; then the optimized separation distance between the two parallel waveguides, 100 nm, is obtained. This optimized architecture fits in the weak coupling regime. Furthermore, the energy transfer is studied, and the performances of the directional coupler are evaluated, including excess loss, coupling degree, and directionality. The results show that when the separation distance is set to 100 nm, the coupling length reaches the shorter value of 1.646 µm, and the propagation loss is as low as 0.076 dB/µm, and the maximum energy transfer can reach 80%. The proposed directional coupler features good energy confinement, ultracompact and low propagation loss, which has potential application in dense photonic-integrated circuits and other photonic devices.

18.
PLoS One ; 11(8): e0161339, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27571417

RESUMO

BACKGROUND: The role of human papilloma virus (HPV) in oral lichen planus (OLP) is controversial. OBJECTIVES: The primary aim of the current study is to calculate the pooled risk estimates of HPV infection in OLP when compared with healthy controls. METHODS: Bibliographic searches were conducted in three electronic databases. Articles on the association between HPV and OLP were selected from case-control studies or cross-sectional studies, following predefined criteria. Pooled data were analyzed by calculating odds ratios (OR) and 95% confidence interval (CI). RESULTS: Of the 233 publications identified, 22 case-control studies met the inclusion criteria. Collectively, 835 cases and 734 controls were available for analysis. The summary estimate showed that OLP patients have significantly higher HPV prevalence (OR: 6.83; 95% CI: 4.15-11.27) than healthy controls. In subgroup analyses, the association of HPV and OLP varied significantly by geographic populations. The ORs ranged from 2.43 to 132.04. The correlation of HPV and erosive-atrophic oral lichen planus (EA-OLP) (OR: 9.34) was comparable and well above that of HPV and non-EA-OLP (OR: 4.32). Among HPV genotypes, HPV 16 showed an extremely strong association with OLP (OR: 11.27), and HPV 18 showed a relatively strong one (OR: 6.54). CONCLUSION: In conclusion, a significant association was found between HPV and OLP. The strength of the association varied across geographic populations, clinical types of OLP, and HPV genotypes. The results suggest that HPV might play an important causal role in OLP and in its malignant to progression.


Assuntos
Líquen Plano Bucal/virologia , Papillomaviridae/fisiologia , Estudos de Casos e Controles , Humanos
19.
Appl Opt ; 54(23): 7037-44, 2015 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-26368373

RESUMO

We researched an elliptic cylindrical silicon nanowire hybrid surface plasmon polariton waveguide and evaluated its mode characteristics using the finite element method software COMSOL. The waveguide consists of three parts: an elliptic cylindrical silicon nanowire, a silver film layer, and a silica covering layer between them. All of the components are surrounded by air. After optimizing the geometrical parameters of the waveguide, we can achieve the waveguide's strong field confinement (ranging from λ2/270 to λ2/27) and long propagation distances (119-485 µm). In order to further understand the impact of the waveguide's architecture on its performance, we also studied the ridge hybrid waveguide. The results show that the ridge waveguide has moderate local field confinement ranging from λ2/190 to λ2/20 and its maximum propagation distance is about 340 µm. We compared the elliptic cylindrical and ridge nanowire hybrid waveguides with the cylindrical hybrid waveguide that we studied before. The elliptic cylindrical waveguide achieves a better trade-off between reasonable mode confinement and maximum propagation length in the three waveguides. The researched hybrid surface plasmon polaritons waveguides are useful to construct devices such as a directional coupler and may find potential applications in photonic integrated circuits or other novel SPP devices.

20.
Parasitol Res ; 114(3): 1001-10, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25547078

RESUMO

There has been no consistent conclusion on whether Sarcoptes mites parasitizing in humans and animals are the same species. To identify Sarcoptes (S.) hominis and S. canis in China, gDNA was extracted from individual mites (five from patients with scabies and five from dogs with mange) for amplification of rDNA ITS2, mtDNA 16S, and cox1 fragment sequences. Then, the sequences obtained were aligned with those from different hosts and geographical locations retrieved from GenBank and sequence analyses were conducted. Phylogenetic trees based on 317-bp mtDNA cox1 showed five distinctive branches (species) of Sarcoptes mites, four for S. hominis (S. hominis Chinese, S. nr. hominis Chinese, S. hominis Australian, and S. hominis Panamanian) and one for S. animal (S. animal). S. animal included mites from nine animal species, with S. canis China, S. canis Australia, and S. canis USA clustering as a subbranch. Further sequence divergence analysis revealed no overlap between intraspecific (≤ 2.6 %) and interspecific (2.6-10.5 %) divergences in 317-bp mtDNA cox1. However, overlap was detected between intra- and interspecific divergences in 311-bp rDNA ITS2 or 275-bp mtDNA 16S when the divergences exceeded 1.0 %, which resulted in failure in identification of Sarcoptes. The results showed that the 317-bp mtDNA cox1 could be used as a DNA barcode for molecular identification of Sarcoptes mites. In addition, geographical isolation was observed between S. hominis Chinese, S. hominis Australian, and S. hominis Panamanian, but not between all S. canis. S. canis and the other S. animal belonged to the same species.


Assuntos
DNA Mitocondrial/genética , DNA Ribossômico/genética , Filogenia , Sarcoptidae/classificação , Sarcoptidae/genética , Distribuição Animal , Animais , Austrália , China , Ciclo-Oxigenase 1/genética , Humanos , Estados Unidos
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