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1.
Asian J Androl ; 2024 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-39285693

RESUMO

Spermatogenesis is a fundamental process that requires a tightly controlled epigenetic event in spermatogonial stem cells (SSCs). The mechanisms underlying the transition from SSCs to sperm are largely unknown. Most studies utilize gene knockout mice to explain the mechanisms. However, the production of genetically engineered mice is costly and time-consuming. In this study, we presented a convenient research strategy using an RNA interference (RNAi) and testicular transplantation approach. Histone H3 lysine 9 (H3K9) methylation was dynamically regulated during spermatogenesis. As Jumonji domain-containing protein 1A (JMJD1A) and Jumonji domain-containing protein 2C (JMJD2C) demethylases catalyze histone H3 lysine 9 dimethylation (H3K9me2), we firstly analyzed the expression profile of the two demethylases and then investigated their function. Using the convenient research strategy, we showed that normal spermatogenesis is disrupted due to the downregulated expression of both demethylases. These results suggest that this strategy might be a simple and alternative approach for analyzing spermatogenesis relative to the gene knockout mice strategy.

2.
Nat Prod Res ; : 1-8, 2024 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-38824429

RESUMO

Three new phenylpropanoids, namely (7'R,8'R) guaiacylglycerol 4'-O-ß-D-[6″-O-(4-O-ß-D-glucopyranosyl)-p-hydroxyl-benzoyl]-glucopyranoside (1), (7 R,8R) guaiacylglycerol 8-O-1'-(2',6'-dimethoxy-4'-O-ß-D-glucopyranosyl)-benzene (2), (7'R,8'R) guaiacylglycerol 4'-O-ß-D-[6″-O-3,5-dimethoxy-4-hydroxylbenzoyl]-gluco-pyranoside (3), along with one known phenylpropanoid (4) were isolated from the ethanol extract of Phyllostachys nigra var. henonis fresh culm. The structures of all compounds were determined by analysis of UV, 1D NMR, 2D NMR, HR-ESI-MS and CD data. All compounds were evaluated for their DPPH radical scavenging activity. Compound 2 (IC50 54.9 µM) and 3 (IC50 77.2 µM) exhibited moderate antioxidant activity compared with two positive control compounds L-ascorbic acid (IC50 15.5 µM) and 2,6-ditertbutyl-4-methyl phenol (IC50 19.1 µM).

3.
Adv Healthc Mater ; 13(18): e2304439, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38486060

RESUMO

Hepatocellular carcinoma (HCC) hematogenous dissemination is a leading cause of HCC-related deaths. The inflammatory facilitates this process by promoting the adhesion and invasion of tumor cells in the circulatory system. But the contribution of hemodynamics to this process remains poorly understood due to the lack of a suitable vascular flow model for investigation. This study develops a vascular flow model to examine the impact of hemodynamics on endothelial inflammation-mediated HCC metastasis. This work finds the increasing shear stress will reduce the recruitment of HCC cells by disturbing adhesion forces between endothelium and HCC cells. However, this reduction will be restored by the inflammation. When applying high FSS (4-6 dyn cm-2) to the inflammatory endothelium, there will be a 4.8-fold increase in HCC cell adhesions compared to normal condition. Nevertheless, the increase fold of cell adhesions is inapparent, around 1.5-fold, with low and medium FSS. This effect can be attributed to the FSS-induced upregulation of ICAM-1 and VCAM-1 of the inflammatory endothelium, which serve to strengthen cell binding forces. These findings indicate that hemodynamics plays a key role in HCC metastasis during endothelial inflammation by regulating the expression of adhesion-related factors.


Assuntos
Carcinoma Hepatocelular , Hemodinâmica , Inflamação , Neoplasias Hepáticas , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas/metabolismo , Humanos , Carcinoma Hepatocelular/patologia , Carcinoma Hepatocelular/metabolismo , Inflamação/patologia , Inflamação/metabolismo , Metástase Neoplásica , Adesão Celular , Molécula 1 de Adesão Intercelular/metabolismo , Endotélio Vascular/patologia , Endotélio Vascular/metabolismo , Molécula 1 de Adesão de Célula Vascular/metabolismo , Células Endoteliais da Veia Umbilical Humana/metabolismo , Linhagem Celular Tumoral , Biomimética/métodos
4.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 55(1): 6-12, 2024 Jan 20.
Artigo em Chinês | MEDLINE | ID: mdl-38322525

RESUMO

Hepatocellular carcinoma (HCC) is one of the leading causes of cancer-related deaths in the world. Due to the insidious onset and rapid progression and a lack of effective treatments, the prognosis of patients with HCC is extremely poor, with the average 5-year survival rate being less than 10%. The tumor microenvironment (TME), the internal environment in which HCC develops, can regulate the oncogenesis, development, invasion, and metastasis of HCC. During the process of cancer progression, HCC cells can regulate the biological behaviors of tumor cells, cancer-associated fibroblasts, cancer-associated immune cells, and other cells in the TME by releasing exosomes containing specific signals, thereby promoting cancer progression. However, the exact molecular mechanisms and the roles of exosomes in the specific cellular regulation of these processes are not fully understood. Herein, we summarized the TME components of HCC, the sources and the biological traits of exosomes in the TME, and the impact of mechanical factors on exosomes. In addition, special attention was given to the discussion of the effects of HCC-exosomes on different types of cells in the microenvironment. There are still many difficulties to be overcome before exosomes can be applied as carriers in clinical cancer treatment. First of all, the homogeneity of exosomes is difficult to ensure. Secondly, exosomes are mainly administered through subcutaneous injection. Although this method is simple and easy to implement, the absorption efficiency is not ideal. Thirdly, exosome extraction methods are limited in number and inefficient, making it difficult to prepare exosomes in large quantities. It is important to ensure that exosomes are used in sufficient quantities to trigger an effective tumor immune response, especially for exosome-mediated tumor immunotherapy. With the improvement in identification, isolation, and purification technology, exosomes are expected to be successfully used in the clinical diagnosis of early-stage HCC and the clinical treatment of liver cancer.


Assuntos
Carcinoma Hepatocelular , Exossomos , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/patologia , Neoplasias Hepáticas/patologia , Microambiente Tumoral , Comunicação Celular
5.
Genes Dis ; 10(2): 583-595, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37223522

RESUMO

Atherosclerosis is a chronic inflammatory disease, occurring preferentially in bifurcation, branching, and bending of blood vessels exposed to disturbed flow. Disturbed flow in atheroprone areas activates elevated proteases, degrading elastin lamellae and collagenous matrix, resulting in endothelial dysfunction and vascular remodeling. As a mediator for extracellular matrix protein degradation, cathepsin K (CTSK) was directly regulated by hemodynamics and contributed to atherosclerosis. The mechanism of CTSK responding to disturbed flow and contributing to disturbed flow-induced atherosclerosis is unclear. In this study, the partial carotid ligation model of mice and in vitro disturbed shear stress model were constructed to explore the contribution and potential mechanism of CTSK in atherosclerosis. Our results indicated that CTSK elevated in the disturbed flow area in vivo and in vitro along with endothelial inflammation and atherogenesis. Additionally, the expression of integrin αvß3 was upregulated in these atheroprone areas. We found that inhibition of the integrin αvß3-cytoskeleton pathway could significantly block the activation of NF-κB and the expression of CTSK. Collectively, our findings unraveled that disturbed flow induces increased CTSK expression, and contributes to endothelial inflammation and vascular remodeling, leading to atherogenesis eventually. This study is helpful to provide new enlightenment for the therapy of atherosclerosis.

6.
Nat Biotechnol ; 40(9): 1370-1377, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35788567

RESUMO

The usefulness of live attenuated virus vaccines has been limited by suboptimal immunogenicity, safety concerns or cumbersome manufacturing processes and techniques. Here we describe the generation of a live attenuated influenza A virus vaccine using proteolysis-targeting chimeric (PROTAC) technology to degrade viral proteins via the endogenous ubiquitin-proteasome system of host cells. We engineered the genome of influenza A viruses in stable cell lines engineered for virus production to introduce a conditionally removable proteasome-targeting domain, generating fully infective PROTAC viruses that were live attenuated by the host protein degradation machinery upon infection. In mouse and ferret models, PROTAC viruses were highly attenuated and able to elicit robust and broad humoral, mucosal and cellular immunity against homologous and heterologous virus challenges. PROTAC-mediated attenuation of viruses may be broadly applicable for generating live attenuated vaccines.


Assuntos
Vacinas contra Influenza , Influenza Humana , Infecções por Orthomyxoviridae , Animais , Furões , Humanos , Vacinas contra Influenza/genética , Influenza Humana/prevenção & controle , Camundongos , Infecções por Orthomyxoviridae/prevenção & controle , Complexo de Endopeptidases do Proteassoma , Proteólise , Vacinas Atenuadas/genética
7.
Front Biosci (Landmark Ed) ; 27(3): 104, 2022 03 17.
Artigo em Inglês | MEDLINE | ID: mdl-35345336

RESUMO

BACKGROUND: Cancer-associated fibroblasts (CAFs) are of considerable importance in tumor progression by interacting with the tumor microenvironment. However, the hidden mechanism explaining how tumor cells interact with CAFs in the tumor mechanical microenvironment remains largely unknown. METHODS: We highlighted exosomes as the mediator modulating the interaction between liver cancer cells and CAFs under mechanical conditions. The normal hepatic stellate cells LX2 were exposed to the medium or exosomes from the HepG2 cells with or without fluid shear stress subjection, and the CAFs activation markers were checked. To further explore the potential role of PI3K, which is active in liver fibrosis, the PI3K inhibitor was used. RESULTS: The specific markers of CAFs, FAP, and α-SMA, increased in LX2 with subjection to the fluid shear stress-induced exosomes from HepG2 cells. In turn, the enriched IGF2 in the exosomes activated the IGF2-PI3K signaling pathway in LX2 cells. CONCLUSIONS: These findings reveal that fluid shear stress-induced liver cancer cells possess a stronger capacity to convert normal fibroblasts to CAFs than statically cultured liver cancer cells, and tumor-derived exosomes mediated the intercellular cross-talk between liver cancer cells and fibroblasts.


Assuntos
Fibroblastos Associados a Câncer , Exossomos , Fibroblastos , Neoplasias Hepáticas , Estresse Mecânico , Fibroblastos Associados a Câncer/metabolismo , Linhagem Celular Tumoral , Proliferação de Células , Exossomos/metabolismo , Fibroblastos/metabolismo , Humanos , Fator de Crescimento Insulin-Like II/metabolismo , Neoplasias Hepáticas/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Microambiente Tumoral
8.
J Infect Prev ; 23(1): 20-24, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35126677

RESUMO

BACKGROUND: Powered Air-Purifying Respirator (PAPR) was widely used in Sengkang General Hospital (SKH) during the SARS-CoV-2 outbreak. Ensuring a sustained supply of clean and reusable PAPR masks for frontline medical team is an immediate challenge. The Central Sterile Supplies Unit (CSSU) adopts existing disinfection methods and technology for the reprocessing of reusable personal protective equipment (PPE) such as PAPR masks and goggles. OBJECTIVE: To determine an effective disinfecting method for protective devices used in the course of treating SARS-CoV2-positive patients. METHOD: A comparison on surface disinfection and modified thermal disinfection outcome was conducted on 30 PAPR masks through detecting the presence of adenosine triphosphate (ATP) by swab following both disinfecting methods. RESULTS: The modified thermal cycles emerged as the recommended disinfection method. DISCUSSION: The outcome of this study has enhanced understanding on the risk imposed on frontline healthcare personnel who perform surface disinfecting on masks for reuse during the work shift. Leveraging on the current expertise from existing instrument logistics, CSSU takes charge of the processing and stock management of SKH's PAPR masks. An additional workflow is needed to establish reprocessing methods for other reusable PPEs such as face shields or overalls.

9.
Front Cell Dev Biol ; 10: 825622, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35127686

RESUMO

Vascular calcification (VC) is linked to an increased risk of heart disease, stroke, and atherosclerotic plaque rupture. It is a cell-active process regulated by vascular cells rather than pure passive calcium (Ca) deposition. In recent years, extracellular vesicles (EVs) have attracted extensive attention because of their essential role in the process of VC. Matrix vesicles (MVs), one type of EVs, are especially critical in extracellular matrix mineralization and the early stages of the development of VC. Vascular smooth muscle cells (VSMCs) have the potential to undergo phenotypic transformation and to serve as a nucleation site for hydroxyapatite crystals upon extracellular stimulation. However, it is not clear what underlying mechanism that MVs drive the VSMCs phenotype switching and to result in calcification. This article aims to review the detailed role of MVs in the progression of VC and compare the difference with other major drivers of calcification, including aging, uremia, mechanical stress, oxidative stress, and inflammation. We will also bring attention to the novel findings in the isolation and characterization of MVs, and the therapeutic application of MVs in VC.

10.
Mol Carcinog ; 60(9): 607-619, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34107107

RESUMO

Hepatocellular carcinoma is a highly fatal disease and threatens human health seriously. Fluid shear stress (FSS), which is caused by the leakage of plasma from abnormally permeable tumor blood vessels and insufficient lymphatic drainage, has been identified as contributing pathologically to cancer metastasis. Autophagy and epithelial-mesenchymal transition (EMT) are both reported to be involved in cancer cell migration and invasion, but little has been revealed about the interaction between autophagy and EMT under a tumor mechanical microenvironment. Here, we identified that exposure to 1.4 dyne/cm2 FSS could promote the formation of autophagosomes and significantly increase the expressions of autophagy-related markers of beclin1 and ATG7, and the ratio of LC3Ⅱ/Ⅰ in both of HepG2 and QGY-7703 cells. The FSS loading also elevated the levels of mesenchymal markers N-cadherin, Vimentin, Twist, Snail, and ß-catenin, while the epithelial markers E-cadherin showed a decrease. Once the autophagy was blocked by 3-methyladenine (3-MA) or knocking ATG5 down, the occurrence of FSS-induced EMT was inhibited dramatically according to the expression and translocation of E-cadherin, N-cadherin, and ß-catenin. Given the effect of EMT on cell migration, we observed that inhibition of autophagy could impede FSS-induced cell migration. Collectively, this study demonstrated that autophagy played a crucial role in FSS-induced EMT and cell migration in hepatocellular carcinoma.


Assuntos
Autofagia , Carcinoma Hepatocelular/etiologia , Carcinoma Hepatocelular/patologia , Transição Epitelial-Mesenquimal , Neoplasias Hepáticas/etiologia , Neoplasias Hepáticas/patologia , Resistência ao Cisalhamento , Autofagossomos/metabolismo , Autofagia/genética , Biomarcadores , Linhagem Celular Tumoral , Movimento Celular , Suscetibilidade a Doenças , Humanos , Microambiente Tumoral
11.
ACS Biomater Sci Eng ; 5(4): 1804-1821, 2019 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-33405555

RESUMO

Gold nanoparticles (Au NPs) have received much attention because of their distinct physicochemical properties. The surface terminal functional groups of Au NPs can facilitate easy conjugation with biological molecules for targeting cancer cells and controlling drugs/genes release. However, little is known regarding molecular mechanisms involved in their regulation of cancer cell migration and invasion. In the present study, Au NPs were successfully conjugated with functional groups (CH3, NH2, OH and COOH) by self-assembled monolayer (SAM) technique. The endocytosis of SAM-Au NPs mediating HepG2 cell migration and invasion in integrin-induced cascaded events were examined. Our results showed that the combination of integrins-Caveolin-1 together contributed to the internalization of SAM-Au NPs. The CH3-Au NPs showed fast cell motility than COOH- and OH- groups by upregulating PI3K expression, but reducing FAK phosphorylation level. Additionally, CH3-Au NPs showed the strongest activated GTP-bound Rac1 and RhoA. Taken together, these results concluded that internalization of SAM-Au NPs inhibited cancer cell migration via FAK/PI3K and downstream Rho-GTPase signaling pathway in a time-dependent manner. This work provides a further understanding of SAM-Au NPs regulating cancer cell migration, which might be helpful to functionalize the Au NP surface in drug delivery system.

12.
Int J Biol Sci ; 14(10): 1277-1290, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30123076

RESUMO

The autophagy in cancer cells is recognized as an essential hallmark of tumors, which can enhance cancer cell migration and invasion, and result in high incidence of tumor metastasis. The fluid shear stress (FSS) in tumor mechanical microenvironment plays a pivotal role in mediating the behaviors and functions of cells. In this study, the hepatocellular carcinoma cells were exposed to 1.4 dyn/cm2 FSS to explore whether FSS could induce autophagy. The results of TEM, Ad-mCherry-GFP labeled LC3B, and mRNA and protein expression of autophagy markers confirmed that FSS could induce autophagy in a time-dependent manner. Additionally, the inhibition of autophagy significantly downregulated the expression of PI3K, FAK and Rho GTPases, and attenuated the ability of cell migration, suggesting that FSS-induced autophagy depended on PI3K- FAK-Rho GTPases pathway. This study elucidated the role of FSS in inducing autophagy during tumor progression, which has emerged as a promising clinical strategy for cancer.


Assuntos
Autofagia/fisiologia , Carcinoma Hepatocelular/metabolismo , Neoplasias Hepáticas/metabolismo , Resistência ao Cisalhamento/fisiologia , Autofagia/genética , Linhagem Celular Tumoral , Movimento Celular , Quinase 1 de Adesão Focal/metabolismo , Células Hep G2 , Humanos , Fosfatidilinositol 3-Quinases/metabolismo , RNA Mensageiro/metabolismo , Proteínas rho de Ligação ao GTP/metabolismo
13.
Gene ; 651: 200-205, 2018 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-29366758

RESUMO

OBJECTIVE: High altitude pulmonary edema (HAPE) is a life threatening condition occurring in otherwise healthy individuals who rapidly ascend to high altitude. However, the molecular mechanisms of its pathophysiology are not well understood. The objective of this study is to evaluate differential gene expression in patients with HAPE during acute illness and subsequent recovery. METHODS: Twenty-one individuals who ascended to an altitude of 3780 m were studied, including 12 patients who developed HAPE and 9 matched controls without HAPE. Whole-blood samples were collected during acute illness and subsequent recovery for analysis of the expression of hypoxia-related genes, and physiologic and laboratory parameters, including mean pulmonary arterial pressure (mPAP), heart rate, blood pressure, and arterial oxygen saturation (SpO2), were also measured. RESULTS: Compared with control subjects, numerous hypoxia-related genes were up-regulated in patients with acute HAPE. Gene network analyses suggested that HIF-1α played a central role in acute HAPE by affecting a variety of hypoxia-related genes, including BNIP3L, VEGFA, ANGPTL4 and EGLN1. Transcriptomic profiling revealed the expression of most HAPE-induced genes was restored to a normal level during the recovery phase except some key hypoxia response factors, such asBNIP3L, EGR1, MMP9 and VEGF, which remained persistently elevated. CONCLUSIONS: Differential expression analysis of hypoxia-related genes revealed distinct molecular signatures of HAPE during acute and recovery phases. This study may help us to better understand HAPE pathogenesis and putative targets for further investigation and therapeutic intervention.


Assuntos
Doença da Altitude/genética , Hipertensão Pulmonar/genética , Edema Pulmonar/genética , Lesão Pulmonar Aguda/etiologia , Lesão Pulmonar Aguda/genética , Adulto , Estudos de Casos e Controles , Estudos de Coortes , Perfilação da Expressão Gênica , Humanos , Regulação para Cima
14.
Cell Adh Migr ; 12(1): 56-68, 2018 01 02.
Artigo em Inglês | MEDLINE | ID: mdl-28636424

RESUMO

Hepatocellular carcinoma (HCC) is a subtype of malignant liver cancer with poor prognosis and limited treatment options. It is noteworthy that mechanical forces in tumor microenvironment play a pivotal role in mediating the behaviors and functions of tumor cells. As an instrumental type of mechanical forces in vivo, fluid shear stress (FSS) has been reported having potent physiologic and pathologic effects on cancer progression. However, the time-dependent mechanochemical transduction in HCC induced by FSS remains unclear. In this study, hepatocellular carcinoma HepG2 cells were exposed to 1.4 dyn/cm2 FSS for transient duration (15s and 30s), short duration (5 min, 15 min and 30 min) and long duration (1h, 2h and 4h), respectively. The expression and translocation of Integrins induced FAK-Rho GTPases signaling events were examined. Our results showed that FSS endowed HepG2 cells with higher migration ability via reorganizing cellular F-actin and disrupting intercellular tight junctions. We further demonstrated that FSS regulated the expression and translocation of Integrins and their downstream signaling cascade in time-dependent patterns. The FSS downregulated focal adhesion components (Paxillin, Vinculin and Talin) while upregulated the expression of Rho GTPases (Cdc42, Rac1 and RhoA) in long durations. These results indicated that FSS enhanced tumor cell migration through Integrins-FAK-Rho GTPases signaling pathway in time-dependent manners. Our in vitro findings shed new light on the role of FSS acting in physiologic and pathological processes during tumor progression, which has emerged as a promising clinical strategy for liver carcinoma.


Assuntos
Carcinoma Hepatocelular/metabolismo , Integrinas/metabolismo , Neoplasias Hepáticas/metabolismo , Estresse Mecânico , Adesão Celular/fisiologia , Movimento Celular/efeitos dos fármacos , Células Hep G2 , Humanos , Neoplasias Hepáticas/tratamento farmacológico , Fosforilação/efeitos dos fármacos , Fatores de Tempo , Regulação para Cima
15.
Oncotarget ; 8(41): 69577-69593, 2017 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-29050226

RESUMO

Tumor angiogenesis plays a central role in the development and metastasis of hepatocellular carcinoma. Cancer cells secrete angiogenic factors to recruit vascular endothelial cells and sustain tumor vascular networks, which facilitate the migration and invasion of cancer cells. Therefore, the cross-talk between vascular endothelial cells and cancer cells is vitally necessary, however, little is known about the cross-talk mechanism of these cells interaction. In the present study, the proliferation, migration, invasion and tube formation of vascular endothelial EA.hy926 cells and hepatocellular carcinoma HepG2 cells were studied by exchanging their culture medium. The time-dependent differences of integrins induced signaling pathway associated with cell migration were investigated. Our results showed that HepG2 cells markedly enhanced the proliferation and migration ability as well as the tube formation of EA.hy926 cells by releasing growth factors. Also, the EA.hy926 cells promoted the proliferation, migration and invasion ability of HepG2 cells. The further analysis demonstrated that the integrins-FAK-Rho GTPases signaling events in both of two cells was activated under conditioned medium, and the signaling molecules in two cell lines showed a different time-dependent expression within 1h. These findings reveal the cross-talk mechanism between the endothelial cells and hepatocellular carcinoma cells, which were expected to find out new ideas for the prevention and treatment of hepatocellular carcinoma.

16.
J Air Waste Manag Assoc ; 67(12): 1319-1327, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-28742986

RESUMO

Mesitylene (or 1,3,5-trimethylbenzene) is a volatile organic compound emitted from various industrial processes, e.g., spray coating. Its emissions have become a critical issue because mesitylene is toxic and cannot be removed using traditional adsorbents, e.g., zeolite (H-ZSM-5; the diameter of mesitylene molecules is greater than the pore size of H-ZSM-5). Hence, an adsorbent with a large pore size, MCM-41, is used in this study to investigate its adsorption capacity for mesitylene and compare with that of H-ZSM-5. Experimental results reveal that MCM-41 without Al2O3 exhibits a good adsorption capacity (184 mg/g) for the gas stream containing 100 ppm of mesitylene at a relative humidity of 10%. The adsorption kinetics is well described by the Freundlich isotherm. Furthermore, experimental results reveal that MCM-41 is effective for the adsorption of low concentrations (10 ppm) of mesitylene. In addition, adsorption-desorption tests revealed that the sample MCM-41-AS is stable to sustain the adsorption capacity after 10 adsorption-desorption cycles. After 10 adsorption-desorption cycles, MCM-41-AS retains 92.4% of its initial adsorption capacity (170 vs. 184 mg/g). Finally, MCM-41 and H-ZSM-5 in series are effective for the simultaneous removal of mesitylene and toluene in the gas stream. IMPLICATIONS: This study aims to improve the performance of adsorbent for mesitylene, which is typically applied in the spray-coating industry. The zeolite MCM-41-AS is selected as a candidate for the investigation. Experimental results reveal that MCM-41-AS exhibits a good adsorption capacity for mesitylene and that it can be integrated with H-ZSM-5-25 for the simultaneous adsorption of mesitylene and toluene.


Assuntos
Derivados de Benzeno/análise , Poluentes Ambientais/análise , Dióxido de Silício/química , Adsorção , Derivados de Benzeno/química , Poluentes Ambientais/química , Cinética , Exposição Ocupacional/prevenção & controle , Tolueno/análise , Tolueno/química
17.
Wilderness Environ Med ; 28(4): 285-290, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28735657

RESUMO

BACKGROUND: Chronic hypoxia-induced pulmonary hypertension and vascular remodeling have been shown to be associated with ornithine decarboxylase 1 (ODC1). However, few animal studies have investigated the role of ODC1 in acute hypoxia. OBJECTIVES: We investigated ODC1 gene expression, morphologic and functional changes, and the effect of L-arginine as an attenuator in lung tissues of rats exposed to acute hypobaric hypoxia at a simulated altitude of 6000 m. METHODS: Sprague-Dawley rats exposed to simulated hypobaric hypoxia (6000 m) for 24, 48, or 72 hours were treated with L-arginine (L-arginine group, 20 mg/100 g intraperitoneal; n=15) or untreated (non-L-arginine group, n=15). Control rats (n=5) were maintained at 2260 m in a normal environment for the same amount of time but were treated without L-arginine. The mean pulmonary artery pressure was measured by PowerLab system. The morphologic and immunohistochemical changes in lung tissue were observed under a microscope. The mRNA and protein levels of ODC1 were measured by real-time polymerase chain reaction and Western-blot, respectively. RESULTS: Hypobaric hypoxia induced pulmonary interstitial hyperemia and capillary expansion in the lungs of rats exposed to acute hypoxia at 6000 m. The mean pulmonary artery pressure and the mRNA and protein levels of ODC1 were significantly increased, which could be attenuated by treatment with L-arginine. CONCLUSIONS: L-arginine attenuates acute hypobaric hypoxia-induced increase in mean pulmonary artery pressure and ODC1 gene expression in lung tissues of rats. ODC1 gene contributes to the development of hypoxic pulmonary hypertension.


Assuntos
Arginina/metabolismo , Pressão Arterial , Expressão Gênica , Hipóxia/fisiopatologia , Inibidores da Ornitina Descarboxilase/metabolismo , Ornitina Descarboxilase/genética , Doença da Altitude/fisiopatologia , Animais , Hipertensão Pulmonar , Hipóxia/etiologia , Hipóxia/genética , Pulmão/metabolismo , Masculino , Ornitina Descarboxilase/metabolismo , Ratos , Ratos Sprague-Dawley
18.
IEEE Trans Image Process ; 26(4): 1952-1964, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28237926

RESUMO

Previous works on palette-based color manipulation typically fail to produce visually pleasing results with vivid color and natural appearance. In this paper, we present an approach to edit colors of an image by adjusting a compact color palette. Different from existing methods that fail to preserve inherent color characteristics residing in the source image, we propose a color decomposition optimization for flexible recoloring while retaining these characteristics. For an input image, we first employ a variant of the k -means algorithm to create a palette consisting of a small set of most representative colors. Next, we propose a color decomposition optimization to decompose colors of the entire image into linear combinations of basis colors in the palette. The captured linear relationships then allow us to recolor the image by recombining the coding coefficients with a user-modified palette. Qualitative comparisons with existing methods show that our approach can more effectively recolor images. Further user study quantitatively demonstrates that our method is a good candidate for color manipulation tasks. In addition, we showcase some applications enabled by our method, including pattern colorings suggesting, color transfer, tissue staining analysis and color image segmentation.

19.
Sheng Wu Yi Xue Gong Cheng Xue Za Zhi ; 34(4): 591-596, 2017 08 25.
Artigo em Chinês | MEDLINE | ID: mdl-29745557

RESUMO

To investigate the effects of Snail1 gene silence on the expression of tight junction proteins and the migration ability of Hep-2 cells, Hep-2 cells were transfected with plasmids which is containing the shRNA of Snail1 gene, and cultured till the cells could be passaged stably (named Sh-snail1 cells). The expression of tight junction proteins (ZO-1, Occludin, Claudin-5) were detected by Western blot. The migration ability of Sh-snail1 cells was investigated by wound healing assay, and the protein expression of members of RhoGTPase family (RhoA, Cdc42) was detected by Western blot, which is closely related to the migration ability. Our results showed that the expression of tight junction proteins (ZO-1, Occludin, Claudin-5) was significantly increased; the migration ability of Sh-snail1 cell was inhibited; the expression of RhoA and Cdc42 was downregulated. All of these indicated that silencing the gene of Snail1 in Hep-2 cells can up-regulate the expression of tight junction proteins and down regulate the expression of Cdc42 and RhoA, and further inhibit the migration of Hep-2 cells. Furthermore, opening of the tight junctions between cells and the stronger migration ability of cancer cells are important processes in cancer metastasis. It is confirmed that the Snail1 gene is closely related to the two processes, providing an experimental basis for targeted therapy of laryngeal squamous cell carcinoma.

20.
Zhongguo Xue Xi Chong Bing Fang Zhi Za Zhi ; 29(6): 788-790, 2017 Dec 12.
Artigo em Chinês | MEDLINE | ID: mdl-29469468

RESUMO

OBJECTIVE: To study the expression profiles of circulating microRNAs (miRNAs) in newly-developed advanced schistosomiasis patients. METHODS: Ten healthy controls (Group 1), ten patients with schistosomiasis history (without advanced schistosomiasis, Group 2) and ten patients with newly-developed advanced schistosomiasis (Group 3) were randomly selected from Jiangsu Province. The expression profiles of 570 human related circulatingmiRNAs were measured and analyzed with the Agilent Human microRNAs microarray Rel 12.0. RESULTS: Compared to the healthy controls, four miRNAs were up-regulated, while 16 miRNAs were down-regulated in the patients with newly-developed advanced schistosomiasis. Moreover, six miRNAs were up-regulated, while 21 miRNAs were down-regulated in the patients in Group 2. Among of them, the expression level of miR-383 was significantly decreased by 4.23 and 11.82 folds in Group 2 and Group 3, respectively. CONCLUSIONS: There are significant differences among the healthy controls, patients with schistosomiasis history (without advanced schistosomiasis) and the patients with newly-developed advanced schistosomiasisin the expression profiles of circulatingmiRNAs. Moreover, circulating miR-383 might be involved in the development of newly-developed advanced schistosomiasis.


Assuntos
MicroRNAs/sangue , Esquistossomose/sangue , Estudos de Casos e Controles , Perfilação da Expressão Gênica , Humanos
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