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1.
Helicobacter ; 29(4): e13109, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38951739

RESUMO

BACKGROUND: Integrin-linked kinase (ILK) is crucial in solid tumors by regulating the Hippo-Yes-associated protein 1 (YAP) pathway. This study aimed to uncover how Helicobacter pylori influences ILK levels and its role in regulating YAP during H. pylori-induced gastric cancer. MATERIALS AND METHODS: GES-1 cells with stable Ilk knockdown and overexpression and a mouse carcinogenesis model for H. pylori infection were constructed. And ILK, the phosphorylated mammalian STE20-like protein kinase 1 (MST1), large tumor suppressor 1 (LATS1; S909, T1079), and YAP (S109, S127) were detected in cells, and mice by western blotting, as well as fluorescence intensity of YAP were assayed by immunofluorescence. YAP downstream genes Igfbp4 and Ctgf, the pathological changes and tumor necrosis factor alpha (TNF-α), interleukin-6 (IL-6), interleukin-1beta (IL-1ß), and nitric oxide (NO) levels in mice gastric tissues were detected by real-time PCR, H&E, and ELISA assays. RESULTS: In this study, stable Ilk knockdown cells exhibited significantly higher phosphorylated levels of MST1, LATS1, and YAP, as well as increased YAP in the nuclei of GES-1 cells. Conversely, cells with Ilk overexpression showed opposite results. H. pylori infection led to decreased ILK levels in gastric epithelial cells but increased ILK levels in gastric cancer cell lines (MGC803, SGC7901) and gastric cancer tissues in mice. Treatment with the ILK inhibitor OST-T315 elevated the phosphorylated MST, LATS1, and YAP levels, and inhibited the mRNA levels of Igfbp4 and Ctgf at 44, 48 week-aged mice. OST-T315 also reduced the release of TNF-α, IL-6, IL-1ß, and NO, as well as the progression of gastric cancer caused by H. pylori and N-Nitroso-N-methylurea (NMU) treatment. CONCLUSION: Upon initiation of gastric tumorigenesis signals, H. pylori increases ILK levels and suppresses Hippo signaling, thereby promoting YAP activation and gastric cancer progression. ILK can serve as a potential prevention target to impede H. pylori-induced gastric cancer.


Assuntos
Infecções por Helicobacter , Helicobacter pylori , Proteínas Serina-Treonina Quinases , Neoplasias Gástricas , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Serina-Treonina Quinases/genética , Animais , Neoplasias Gástricas/microbiologia , Neoplasias Gástricas/patologia , Neoplasias Gástricas/metabolismo , Neoplasias Gástricas/genética , Infecções por Helicobacter/microbiologia , Infecções por Helicobacter/patologia , Camundongos , Humanos , Modelos Animais de Doenças , Linhagem Celular , Masculino
2.
PLoS Genet ; 17(9): e1009432, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34506495

RESUMO

Epigenetic alterations occur as organisms age, and lead to chromatin deterioration, loss of transcriptional silencing and genomic instability. Dysregulation of the epigenome has been associated with increased susceptibility to age-related disorders. In this study, we aimed to characterize the age-dependent changes of the epigenome and, in turn, to understand epigenetic processes that drive aging phenotypes. We focused on the aging-associated changes in the repressive histone marks H3K9me3 and H3K27me3 in C. elegans. We observed region-specific gain and loss of both histone marks, but the changes are more evident for H3K9me3. We further found alteration of heterochromatic boundaries in aged somatic tissues. Interestingly, we discovered that the most statistically significant changes reflected H3K9me3-marked regions that are formed during aging, and are absent in developing worms, which we termed "aging-specific repressive regions" (ASRRs). These ASRRs preferentially occur in genic regions that are marked by high levels of H3K9me2 and H3K36me2 in larval stages. Maintenance of high H3K9me2 levels in these regions have been shown to correlate with a longer lifespan. Next, we examined whether the changes in repressive histone marks lead to de-silencing of repetitive DNA elements, as reported for several other organisms. We observed increased expression of active repetitive DNA elements but not global re-activation of silent repeats in old worms, likely due to the distributed nature of repetitive elements in the C. elegans genome. Intriguingly, CELE45, a putative short interspersed nuclear element (SINE), was greatly overexpressed at old age and upon heat stress. SINEs have been suggested to regulate transcription in response to various cellular stresses in mammals. It is likely that CELE45 RNAs also play roles in stress response and aging in C. elegans. Taken together, our study revealed significant and specific age-dependent changes in repressive histone modifications and repetitive elements, providing important insights into aging biology.


Assuntos
Envelhecimento/genética , Caenorhabditis elegans/genética , Histonas/genética , Animais , Proteínas de Caenorhabditis elegans/genética , Mutação , RNA/genética , RNA/metabolismo , Receptores Notch/genética , Retroelementos , Estresse Fisiológico/genética
3.
Chemistry ; 29(42): e202300973, 2023 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-37100743

RESUMO

Electrooxidation of 5-hydroxymethylfural (HMF) into 2,5-furandicarboxylicacid (FDCA) has been regarded as a promising sustainable approach to achieve value-added chemicals. However, it is still impeded by the unsatisfactory performance of electrocatalysts. Here, Cu2 P7 -CoP heterostructure nanosheets were reported to enable powerful HMF electrooxidation. The Cu2 P7 -CoP heterostructure nanosheets were fabricated by microwave-assisted deep eutectic solvent (DES) approach, along with subsequent phosphiding. The Cu2 P7 -CoP heterostructure nanosheets enabled a superb 100 % HMF conversion at 1.43 V (vs. RHE) with 98.8 % FDCA yield and 98 % Faradaic efficiency (FE), demonstrating its promising application in HMF electrooxidation. X-ray photoelectron spectroscopy (XPS) analysis, open-circuit potential (OCP) approach and density functional theory (DFT) calculation uncovered that the electron transfer and redistribution between Cu2 P7 and CoP improved the adsorption capacity of HMF and modulated the catalytic performance. This study not only offered a powerful electrocatalyst for HMF electrooxidation, but also provided a conceptually new strategy for the heterostructure catalyst design.

4.
Ecotoxicology ; 32(1): 57-72, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36567403

RESUMO

The widespread spread of antibiotic resistance genes (ARGs) in hyporheic zone (HZ) has become an emerging environmental problem due to their potentially harmful nature. In this research, three different oxygen treatment systems were set up to study the effects of oxygen changes on the abundance of ARGs in the HZ. In addition, the effects of temperature and salinity on ARGs were investigated under aerobic and anaerobic systems, respectively. The bacterial community composition of sediment samples and the relationship with ARGs were analyzed. The explanation ratio and causality of the driving factors affecting ARGs were analyzed using variation partitioning analysis (VPA) and structural equation model (SEM). The relative abundance of ARGs and mobile genetic elements (MGEs) in the anaerobic system increased significantly, which was higher than that in the aerobic system and the aerobic-anaerobic interaction system. The experiment of salinity and temperature also further proved this result. There were many bacterial communities that affected tetracycline and sulfonamide ARGs in sediments, and these host bacteria are mainly concentrated in Proteobacteria, Firmicutes and Bacteroidetes. VPA and SEM further revealed that the abundance of ARGs was mainly influenced by changes in bacterial communities and oxygen conditions, and horizontal gene transfer (HGT) of MGEs also had a positive effect on the spread of ARGs. Those findings suggest that complex oxygen conditions in the HZ alter bacterial communities and promote MGEs-mediated horizontal transfer, which together lead to the spread of ARGs. This study has value as a reference for formulating effective strategies to minimize the propagation of ARGs in underground environment.


Assuntos
Antibacterianos , Genes Bacterianos , Antibacterianos/farmacologia , Bactérias/genética , Resistência Microbiana a Medicamentos/genética , Sulfanilamida
5.
BMC Genomics ; 23(1): 842, 2022 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-36539699

RESUMO

BACKGROUND: Organisms in the wild can acquire disease- and stress-resistance traits that outstrip the programs endogenous to humans. Finding the molecular basis of such natural resistance characters is a key goal of evolutionary genetics. Standard statistical-genetic methods toward this end can perform poorly in organismal systems that lack high rates of meiotic recombination, like Caenorhabditis worms. RESULTS: Here we discovered unique ER stress resistance in a wild Kenyan C. elegans isolate, which in inter-strain crosses was passed by hermaphrodite mothers to hybrid offspring. We developed an unbiased version of the reciprocal hemizygosity test, RH-seq, to explore the genetics of this parent-of-origin-dependent phenotype. Among top-scoring gene candidates from a partial-coverage RH-seq screen, we focused on the neuronally-expressed, cuticlin-like gene cutl-24 for validation. In gene-disruption and controlled crossing experiments, we found that cutl-24 was required in Kenyan hermaphrodite mothers for ER stress tolerance in their inter-strain hybrid offspring; cutl-24 was also a contributor to the trait in purebred backgrounds. CONCLUSIONS: These data establish the Kenyan strain allele of cutl-24 as a determinant of a natural stress-resistant state, and they set a precedent for the dissection of natural trait diversity in invertebrate animals without the need for a panel of meiotic recombinants.


Assuntos
Proteínas de Caenorhabditis elegans , Caenorhabditis , Humanos , Animais , Caenorhabditis elegans/genética , Quênia , Fenótipo , Proteínas de Caenorhabditis elegans/genética
6.
Med Sci Monit ; 27: e930921, 2021 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-34408123

RESUMO

BACKGROUND Diabetes is related to higher risk of multiple cancers. This study aimed to explore the effect and mechanism of diabetes on liver metastasis of CRC. MATERIAL AND METHODS Overall and liver metastasis-free survival in diabetic and non-diabetic CRC patients were compared by Kaplan-Meier analysis. Expression of alphavß6 was detected by immunohistochemistry in clinical specimens. Effects of hyperglycemia on alphavß6 expression in colon cancer cells were assessed by western blot, real-time PCR, and flowcytometry. Effects of hyperglycemia on migration and invasion were demonstrated by Transwell assay. Expression and activity of MMP-9 and MMP-2 were determined by real-time PCR and gelatin zymography. Liver metastatic nodules were counted and b6 expression was detected by western blot in a liver metastasis mouse model. RESULTS CRC patients with diabetes had poorer overall and liver metastasis-free survival, and diabetes was associated with higher alphavß6 expression in CRC specimens. Hyperglycemia promoted the invasion and migration of colon cancer cells, and upregulated the expression and activity of MMP-9, which were attenuated by inhibition of alphavß6. Hyperglycemia upregulated the expression of ß6 and cell surface expression of avb6, which was reduced by ERK inhibitor. The in vitro results were confirmed in vivo in the mouse model. CONCLUSIONS Our study demonstrated the enhancing effect of hyperglycemia on liver metastasis of CRC, and showed that alphavß6 was involved in this process, suggesting that control of glucose levels and inhibition of alphavß6 can reduce the risk of liver metastasis in diabetic CRC patients.


Assuntos
Antígenos de Neoplasias/metabolismo , Neoplasias Colorretais/sangue , Hiperglicemia/metabolismo , Integrinas/metabolismo , Adulto , Animais , Antígenos de Neoplasias/genética , Linhagem Celular Tumoral , Movimento Celular/fisiologia , Proliferação de Células/fisiologia , Neoplasias Colorretais/genética , Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/patologia , Transição Epitelial-Mesenquimal , Feminino , Expressão Gênica , Humanos , Hiperglicemia/patologia , Integrinas/genética , Neoplasias Hepáticas/genética , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Pessoa de Meia-Idade , Metástase Neoplásica , RNA Longo não Codificante , Regulação para Cima
7.
PLoS Genet ; 14(6): e1007466, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29912876

RESUMO

Tri-methylation on histone H3 lysine 4 (H3K4me3) is associated with active gene expression but its regulatory role in transcriptional activation is unclear. Here we used Caenorhabditis elegans to investigate the connection between H3K4me3 and gene expression regulation during aging. We uncovered around 30% of H3K4me3 enriched regions to show significant and reproducible changes with age. We further showed that these age-dynamic H3K4me3 regions largely mark gene-bodies and are acquired during adult stages. We found that these adult-specific age-dynamic H3K4me3 regions are correlated with gene expression changes with age. In contrast, H3K4me3 marking established during developmental stages remained largely stable with age, even when the H3K4me3 associated genes exhibited RNA expression changes during aging. Importantly, the genes associated with changes in H3K4me3 and RNA levels with age are enriched for functional groups commonly implicated in aging biology. Therefore, our findings suggested divergent roles of H3K4me3 in gene expression regulation during aging, with important implications on aging-dependent pathophysiologies.


Assuntos
Histonas/genética , Histonas/metabolismo , Fatores Etários , Animais , Caenorhabditis elegans/citologia , Caenorhabditis elegans/metabolismo , Metilação de DNA , Epigênese Genética/genética , Regulação da Expressão Gênica , Lisina/metabolismo , Metilação , Ativação Transcricional/genética , Ativação Transcricional/fisiologia
8.
J Acoust Soc Am ; 150(2): 1140, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34470258

RESUMO

A three-dimensional (3D) finite difference (FD) model with formal fourth-order accuracy has been developed for the ocean acoustic Helmholtz equation (HE), which can be used to address arbitrary bathymetry and provide more accurate benchmark solutions for other 3D underwater acoustic approximate models. The derivatives in the acoustic HE are numerically discretized based on regular grids, and the perfectly matched layer is introduced to absorb unphysical reflections from the boundaries where Sommerfeld radiation conditions are deployed. The system of linear equations is solved using a parallel matrix-free geometric multigrid preconditioned biconjugate gradient stabilized iteration method, and the code (named COACH) is run on the Tianhe-2 supercomputer in China. Four 3D topographic benchmark acoustic cases-a wedge waveguide, Gaussian canyon, conical seamount, and corrugated seabed-are simulated to test the present FD model, and the maximum number of grid points reaches 33.15 × 109 in the wedge waveguide case, running in parallel with 988 central processing unit cores. Furthermore, the accuracy and generality of the present model have been verified by solution comparisons with other available 3D acoustic propagation models, and the two-dimensional and 3D transmission loss contours are presented to facilitate the distinguishing among the acoustic field features of these cases.

9.
BMC Cancer ; 20(1): 686, 2020 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-32703187

RESUMO

BACKGROUND: In this study, we examined the differential associations of various proinflammatory and anti-inflammatory cytokines with depression severity from the development of breast cancer to subsequent chemotherapy treatment. METHODS: A cross-sectional study was conducted on a sample of 116 women: 29 controls without cancer, 55 patients with breast cancer who were not receiving chemotherapy, and 32 patients with breast cancer who were receiving chemotherapy. Blood samples were assayed to evaluate serum levels of the following cytokines: interferon-γ, interleukin (IL)-12 (p70), IL-1ß, IL-2, tumor necrosis factor (TNF)-α, IL-4, IL-5, IL-10, IL-13, IL-6, and IL-17A. Depression severity was assessed using the Patient Health Questionnaire. RESULTS: After adjustment for sociodemographics, consistent patterns of the association between cytokine and depression were noted in the different groups. No significant associations were observed in the controls. Inverse associations were observed between cytokines levels and depression severity in patients with breast cancer who were not receiving chemotherapy, whereas positive associations were noted in patients with breast cancer who were receiving chemotherapy. Specific differential relationships between IL-5 levels and depression severity were found between patients with breast cancer who were receiving and not receiving chemotherapy. CONCLUSIONS: Our study revealed differential relationships between cytokine levels and depression severity with the development of cancer. Immunostimulation and immunosuppression in breast cancer and cancer treatment may account for the differential responses with the development of breast cancer.


Assuntos
Neoplasias da Mama/sangue , Depressão/sangue , Interferon gama/sangue , Interleucinas/sangue , Fator de Necrose Tumoral alfa/sangue , Adulto , Idoso , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/imunologia , Estudos Transversais , Depressão/imunologia , Feminino , Humanos , Mediadores da Inflamação/sangue , Pessoa de Meia-Idade , Índice de Gravidade de Doença
10.
Bioorg Med Chem Lett ; 28(2): 94-102, 2018 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-29233653

RESUMO

LpxC inhibitors are new-type antibacterial agents developed in the last twenty years, mainly against Gram-negative bacteria infections. To develop novel LpxC inhibitors with good antibacterial activities and biological metabolism, we summarized the basic skeleton of reported LpxC inhibitors, designed and synthesized several series of compounds and tested their antibacterial activities against Escherichial coli and Pseudomonas aeruginosa in vitro. Structure-activity relationships have been discussed in this article. The metabolism stability of YDL-2, YDL-5, YDL-8, YDL-14, YDL-20-YDL-23 have been evaluated in liver microsomes, which indicated that the 2-amino isopropyl group may be a preferred structure than the 2-hydroxy ethyl group in the design of LpxC inhibitors.


Assuntos
Amidoidrolases/antagonistas & inibidores , Antibacterianos/farmacologia , Desenho de Fármacos , Inibidores Enzimáticos/farmacologia , Escherichia coli/efeitos dos fármacos , Pseudomonas aeruginosa/efeitos dos fármacos , Amidoidrolases/metabolismo , Antibacterianos/síntese química , Antibacterianos/química , Relação Dose-Resposta a Droga , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/química , Testes de Sensibilidade Microbiana , Estrutura Molecular , Relação Estrutura-Atividade
11.
BMC Genomics ; 18(Suppl 7): 753, 2017 10 16.
Artigo em Inglês | MEDLINE | ID: mdl-29513197

RESUMO

BACKGROUND: Identifying rare germline and somatic variants associated with cancer progression is an important research topic in cancer genomics. Although many approaches are proposed for rare variant association study, they are not fit for cancer sequencing data due to multiple issues, such as overly relying on pre-selection, losing sight of interacting hotspots, etc. RESULTS: In this article, we propose an improved pipeline to identify germline variant and somatic mutation interactions influencing cancer susceptibility from pair-wise cancer sequencing data. The proposed pipeline, RareProb-C performs an algorithmic selection on the given variants by incorporating the variant allelic frequencies. The interactions among the variants are considered within the regions which are limited by a four-gamete test. Then it filters singular cases according to the posterior probability at each site. Finally, it outputs the selected candidates that pass a collapse test. CONCLUSIONS: We apply RareProb-C on a series of carefully constructed simulation cases and it outperforms six existing genetic model-free approaches. We also test RareProb-C on 429 TCGA ovarian cancer cases, and RareProb-C successfully identifies the known highlighted variants which are considered increasing disease susceptibilities.


Assuntos
Genômica/métodos , Mutação em Linhagem Germinativa/genética , Algoritmos , Análise Mutacional de DNA , Progressão da Doença , Neoplasias/genética
12.
PLoS Genet ; 10(1): e1004108, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24453993

RESUMO

Seminal fluid proteins transferred from males to females during copulation are required for full fertility and can exert dramatic effects on female physiology and behavior. In Drosophila melanogaster, the seminal protein sex peptide (SP) affects mated females by increasing egg production and decreasing receptivity to courtship. These behavioral changes persist for several days because SP binds to sperm that are stored in the female. SP is then gradually released, allowing it to interact with its female-expressed receptor. The binding of SP to sperm requires five additional seminal proteins, which act together in a network. Hundreds of uncharacterized male and female proteins have been identified in this species, but individually screening each protein for network function would present a logistical challenge. To prioritize the screening of these proteins for involvement in the SP network, we used a comparative genomic method to identify candidate proteins whose evolutionary rates across the Drosophila phylogeny co-vary with those of the SP network proteins. Subsequent functional testing of 18 co-varying candidates by RNA interference identified three male seminal proteins and three female reproductive tract proteins that are each required for the long-term persistence of SP responses in females. Molecular genetic analysis showed the three new male proteins are required for the transfer of other network proteins to females and for SP to become bound to sperm that are stored in mated females. The three female proteins, in contrast, act downstream of SP binding and sperm storage. These findings expand the number of seminal proteins required for SP's actions in the female and show that multiple female proteins are necessary for the SP response. Furthermore, our functional analyses demonstrate that evolutionary rate covariation is a valuable predictive tool for identifying candidate members of interacting protein networks.


Assuntos
Drosophila melanogaster/genética , Peptídeos/genética , Reprodução/genética , Proteínas de Plasma Seminal/genética , Comportamento Sexual Animal , Animais , Copulação , Drosophila melanogaster/fisiologia , Feminino , Fertilidade/genética , Masculino , Oviposição/genética , Peptídeos/metabolismo , Proteínas de Plasma Seminal/isolamento & purificação , Proteínas de Plasma Seminal/metabolismo , Espermatozoides/metabolismo
13.
Water Sci Technol ; 76(2): 471-477, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28726712

RESUMO

In the last 10 years, the microbial fuel cell (MFC) has been extensively studied worldwide to extract energy from wastewater via electricity generation. More recently, a merged technique of embedding MFC into a constructed wetland (CW) has been developed and appears to be increasingly investigated. The driving force to integrate these two technologies lies in the fact that CWs naturally possess a redox gradient (depending on flow direction and wetland depth), which is required by MFCs as anaerobic anode and aerobic cathode chambers. No doubt, the integration of MFC with a CW will upgrade the CW to allow it to be used for wastewater treatment and, simultaneously, electricity generation, making CWs more sustainable and environmentally friendly. Currently, published work shows that India, China, Ireland, Spain, Germany and Malaysia are involved in the development of this technology although it is in its infant stage and many technical issues are faced on system configuration, operation and maximisation of electricity production. This paper aims to provide an updated review and analysis of the CW-MFC development. Focuses are placed on the experience gained so far from different researchers in the literature and further research directions and proposals are discussed in great detail.


Assuntos
Fontes de Energia Bioelétrica , Eliminação de Resíduos Líquidos/métodos , Áreas Alagadas , Eletricidade , Eletrodos , Águas Residuárias
16.
Eur Heart J ; 35(14): 911-9, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23999450

RESUMO

AIMS: The aim of this study was to investigate the effect of Arginase I (ArgI) on plaque stabilization in unruptured atherosclerotic plaque and explore its mechanism. METHODS AND RESULTS: The atherosclerotic plaque model was established in New Zealand rabbits by balloon injury of abdominal arteries and a high cholesterol (1%) diet. Arginase I overexpression reduced the content of macrophages and lipids and increased that of smooth muscle cells and collagen in the atherosclerotic plaque, thus contributing to decreased plaque vulnerability. Arginase I overexpression decreased the expression of the inflammatory cytokines tumour necrosis factor-α (TNF-α) and interleukin-6 (IL-6) as well as inducible nitric oxide synthase (iNOS) in plaques. In vitro, ArgI overexpression or iNOS inhibition abolished the secretion of TNF-α and IL-6 induced by lipopolysaccharide in Raw264.7 cells. However, exogenous l-arginine restored the expression of inflammatory cytokines. Arginase I overexpression inhibited the activity of iNOS without changing its expression. Moreover, ArgI co-localized with iNOS in both Raw264.7 cells and human aortic atherosclerotic plaques. In addition, the IL-10 level was increased in plaque with ArgI overexpression. Finally, ArgI promoted aortic vascular smooth muscle cell proliferation, which was associated with increased production of intracellular polyamines. CONCLUSION: ArgI enhances the stability of atherosclerotic plaque by inhibiting the expression of inflammatory cytokines and stimulating smooth muscle cell proliferation.


Assuntos
Arginase/metabolismo , Músculo Liso Vascular/enzimologia , Miócitos de Músculo Liso/enzimologia , Placa Aterosclerótica/enzimologia , Animais , Proliferação de Células/fisiologia , Interleucina-6/metabolismo , Óxido Nítrico Sintase Tipo II/antagonistas & inibidores , Óxido Nítrico Sintase Tipo II/metabolismo , Coelhos , Fator de Necrose Tumoral alfa/metabolismo
17.
Water Sci Technol ; 71(12): 1775-82, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26067496

RESUMO

Globally, alum sludge is an easily, locally and largely available by-product from water treatment plants where aluminium sulphate is used as the coagulant for raw water purification. Owing to the high content of Al ions (29.7±13.3% dry weight) in alum sludge and the strong affinity of Al ions to adsorb various pollutants especially phosphorus (P), alum sludge (in the form of dewatered cakes) has been investigated in recent years as a low-cost alternative substrate in constructed wetland (CW) systems to enhance the treatment efficiency especially for high strength P-containing wastewater. Long-term trials in different scales have demonstrated that the alum sludge-based CW is a promising technique with a two-pronged feature of using 'waste' for wastewater treatment. Alum sludge cakes in CW can serve as a medium for wetland plant growth, as a carrier for biofilm development and as a porous material for wastewater infiltration. After the intensive studies of the alum sludge-based CW system, this paper aims to address the key issues and concerns pertaining to this kind of CW system. These include: (1) Is alum sludge suitable for reuse in CWs? (2) Is Al released from the sludge a concern? (3) What is the lifespan of the alum sludge in CWs? (4) How can P be recovered from the used alum sludge? (5) Does clogging happen in alum sludge-based CW systems and what is the solution?


Assuntos
Compostos de Alúmen/química , Esgotos/química , Áreas Alagadas , Adsorção , Alumínio/química , Fósforo/química , Reciclagem , Eliminação de Resíduos Líquidos/métodos , Poluentes Químicos da Água/química , Purificação da Água/métodos
18.
Carcinogenesis ; 35(2): 282-91, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24085800

RESUMO

Colorectal cancer (CRC) displays a predilection for metastasis to liver. Although stromal cell-derived factor-1 (SDF-1)/CXCR4 plays an important role in the liver metastasis, the molecular mechanism still remains obscure. We previously reported that integrin αvß6 was implicated in the progression of CRC. However, no data are currently available on the cross talk between CXCR4 and αvß6. In the present study, we first demonstrated the cross talk between CXCR4 and αvß6 and their role in liver metastasis of CRC. We analyzed 159 human CRC samples and found that expression of CXCR4 and αvß6 was significantly associated with liver metastasis, and interestingly expression of αvß6 significantly correlated with expression of CXCR4. Both CXCR4 and αvß6 were highly expressed in metastatic CRC cell lines HT-29 and WiDr, whereas both of them were exiguous in non-metastatic cell line Caco-2. Furthermore, inhibition of αvß6 significantly decreased SDF-1α-induced cell migration in vitro. SDF-1/CXCR4 could upregulate αvß6 expression through phosphorylation of ERK and activation of Ets-1 transcription factor. In conclusion, we demonstrate that SDF-1/CXCR4 induces directional migration and liver metastasis of CRC cells by upregulating αvß6 through ERK/Ets-1 pathway. These data support combined inhibition of CXCR4 and αvß6 to prevent development of liver metastasis of CRC.


Assuntos
Antígenos de Neoplasias/metabolismo , Movimento Celular , Quimiocina CXCL12/metabolismo , Neoplasias Colorretais/patologia , Integrinas/metabolismo , Neoplasias Hepáticas/secundário , Proteína Proto-Oncogênica c-ets-1/metabolismo , Receptores CXCR4/metabolismo , Antígenos de Neoplasias/genética , Apoptose , Western Blotting , Células CACO-2 , Proliferação de Células , Quimiocina CXCL12/genética , Neoplasias Colorretais/genética , Neoplasias Colorretais/metabolismo , Ensaio de Desvio de Mobilidade Eletroforética , Citometria de Fluxo , Imunofluorescência , Células HT29 , Humanos , Técnicas Imunoenzimáticas , Integrinas/genética , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , Proteína Proto-Oncogênica c-ets-1/genética , RNA Mensageiro/genética , Reação em Cadeia da Polimerase em Tempo Real , Receptores CXCR4/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa
19.
J Cell Mol Med ; 18(11): 2311-20, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25210949

RESUMO

Apoptosis is a key event involved in diabetic cardiomyopathy. The expression of high mobility group box 1 protein (HMGB1) is up-regulated in diabetic mice. However, the molecular mechanism of high glucose (HG)-induced cardiomyocyte apoptosis remains obscure. We aimed to determine the role of HMGB1 in HG-induced apoptosis of cardiomyocytes. Treating neonatal primary cardiomyocytes with HG increased cell apoptosis, which was accompanied by elevated levels of HMGB1. Inhibition of HMGB1 by short-hairpin RNA significantly decreased HG-induced cell apoptosis by reducing caspase-3 activation and ratio of Bcl2-associated X protein to B-cell lymphoma/leukemia-2 (bax/bcl-2). Furthermore, HG activated E26 transformation-specific sequence-1 (Ets-1), and HMGB1 inhibition attenuated HG-induced activation of Ets-1 via extracellular signal-regulated kinase 1/2 (ERK1/2) signalling. In addition, inhibition of Ets-1 significantly decreased HG-induced cardiomyocyte apoptosis. Similar results were observed in streptozotocin-treated diabetic mice. Inhibition of HMGB1 by short-hairpin RNA markedly decreased myocardial cell apoptosis and activation of ERK and Ets-1 in diabetic mice. In conclusion, inhibition of HMGB1 may protect against hyperglycaemia-induced cardiomyocyte apoptosis by down-regulating ERK-dependent activation of Ets-1.


Assuntos
Apoptose/genética , Diabetes Mellitus Experimental/genética , Cardiomiopatias Diabéticas/genética , Proteína HMGB1/genética , Proteína Proto-Oncogênica c-ets-1/metabolismo , Animais , Diabetes Mellitus Experimental/patologia , Cardiomiopatias Diabéticas/patologia , Proteína HMGB1/antagonistas & inibidores , Humanos , Hiperglicemia/metabolismo , Hiperglicemia/patologia , Proteínas Quinases JNK Ativadas por Mitógeno/genética , Camundongos , Camundongos Endogâmicos NOD , Miócitos Cardíacos/metabolismo , Miócitos Cardíacos/patologia , Fosforilação , Transdução de Sinais/genética , Proteína X Associada a bcl-2/genética
20.
Biochim Biophys Acta ; 1833(1): 59-68, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23085506

RESUMO

BACKGROUND: Atherosclerosis begins as local inflammation of vessels at sites of disturbed flow, where low shear stress (LSS) leads to mechanical irritation and plaque development and progression. Nuclear enzyme poly(ADP-ribose) polymerase 1 (PARP-1) is associated with the inflammation response during atherosclerosis. We investigated the role and underlying mechanism of PARP-1 in LSS-induced inflammation in human umbilical vein endothelial cells (HUVECs). METHODS AND RESULTS: HUVECs were simulated by LSS (0.4Pa). PARP-1 expression was inhibited by ABT888 or siRNA. The inducible nitric oxide synthase (iNOS) and intercellular adhesion molecular-1 (ICAM-1) expression was regulated by LSS in a time dependent manner. LSS could increase superoxide production and 3-nitrotyrosine formation. LSS induced DNA damage as assessed by H2A.X phosphorylation and comet assay. Compared with cells under static, LSS increased PARP-1 expression and PAR formation via MEK/ERK signaling pathway. PARP-1 inhibition increased Sirt1 activity through an increased intracellular nicotinamide adenine dinucleotide (NAD(+)) level. Moreover, PARP-1 inhibition attenuated LSS-induced iNOS and ICAM-1 upregulation by inhibiting nuclear factor kappa B (NF-κB) nuclear translocation and activity, with a reduced NF-κB phosphorylation. CONCLUSIONS: LSS induced oxidative damage and PARP-1 activation via MEK/ERK pathway. PARP-1 inhibition restored Sirt1 activity by increasing NAD(+) level and decreased iNOS and ICAM-1 expression by inhibiting NF-κB nuclear translocation and activity as well as NF-κB phosphorylation. PARP-1 played a fundamental role in LSS induced inflammation. Inhibition of PARP-1 might be a mechanism for treatment of inflammation response during atherosclerosis.


Assuntos
Citoproteção/efeitos dos fármacos , Inflamação/prevenção & controle , Inibidores de Poli(ADP-Ribose) Polimerases , RNA Interferente Pequeno/farmacologia , Estresse Mecânico , Células Cultivadas , Citoproteção/genética , Inibidores Enzimáticos/farmacologia , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Células Endoteliais da Veia Umbilical Humana/metabolismo , Células Endoteliais da Veia Umbilical Humana/fisiologia , Humanos , Inflamação/etiologia , Inflamação/genética , Inflamação/metabolismo , Mediadores da Inflamação/metabolismo , Óxido Nítrico Sintase Tipo II/genética , Óxido Nítrico Sintase Tipo II/metabolismo , Poli(ADP-Ribose) Polimerase-1 , Poli(ADP-Ribose) Polimerases/genética , Poli(ADP-Ribose) Polimerases/metabolismo , Resistência ao Cisalhamento/efeitos dos fármacos , Resistência ao Cisalhamento/fisiologia , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/genética , Fatores de Tempo
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