RESUMO
The performance optimization of isolated atomically dispersed metal active sites is critical but challenging. Here, TiO2@Fe species-N-C catalysts with Fe atomic clusters (ACs) and satellite Fe-N4 active sites were fabricated to initiate peroxymonosulfate (PMS) oxidation reaction. The AC-induced charge redistribution of single atoms (SAs) was verified, thus strengthening the interaction between SAs and PMS. In detail, the incorporation of ACs optimized the HSO5- oxidation and SO5·- desorption steps, accelerating the reaction progress. As a result, the Vis/TiFeAS/PMS system rapidly eliminated 90.81% of 45 mg/L tetracycline (TC) in 10 min. The reaction process characterization suggested that PMS as an electron donor would transfer electron to Fe species in TiFeAS, generating 1O2. Subsequently, the hVB+ can induce the generation of electron-deficient Fe species, promoting the reaction circulation. This work provides a strategy to construct catalysts with multiple atom assembly-enabled composite active sites for high-efficiency PMS-based advanced oxidation processes (AOPs).
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Despite the increasing prevalence of atmospheric nanoplastics (NPs), there remains limited research on their phytotoxicity, foliar absorption, and translocation in plants. In this study, we aimed to fill this knowledge gap by investigating the physiological effects of tomato leaves exposed to differently charged NPs and foliar absorption and translocation of NPs. We found that positively charged NPs caused more pronounced physiological effects, including growth inhibition, increased antioxidant enzyme activity, and altered gene expression and metabolite composition and even significantly changed the structure and composition of the phyllosphere microbial community. Also, differently charged NPs exhibited differential foliar absorption and translocation, with the positively charged NPs penetrating more into the leaves and dispersing uniformly within the mesophyll cells. Additionally, NPs absorbed by the leaves were able to translocate to the roots. These findings provide important insights into the interactions between atmospheric NPs and crop plants and demonstrate that NPs' accumulation in crops could negatively impact agricultural production and food safety.
Assuntos
Antioxidantes , MicroplásticosRESUMO
Vacancy engineering can modulate the electronic structure of the material and thus contribute to the formation of coordination unsaturated sites, which makes it easier to act on the substrate. Herein, Ag2 S and Ag2 S-100, which mainly have vacancy associates VAgS and VAgSAg , respectively, are prepared and characterized by positron annihilation spectroscopy. Both experimental and theoretical calculation results indicate that Ag2 S-100 exhibits excellent antibacterial activity due to its appropriate bandgap and stronger bacteria-binding ability, which endow it with a superior antibacterial activity compared to Ag2 S in the absence of light. The in vivo antibacterial experiment using a mouse wound-infection model further confirms that Ag2 S-100 has excellent antibacterial and wound-healing properties. This research provides clues for a deeper understanding of modulating electronic structures through vacancy engineering and develops a strategy for effective treatment of bacterial infections.
Assuntos
Infecções Bacterianas , Antibacterianos/química , Antibacterianos/farmacologia , Bactérias , Eletrônica , Humanos , CicatrizaçãoRESUMO
Dissipating energy by activating thermogenic adipose to combating obesity attracts many interests. Ski-interacting protein (Skip) has been known to play an important role in cell proliferation and differentiation, but whether it participates in energy metabolism is not known. Our previous study revealed that BTM-0512 could induce beige adipose formation, accompanying with up-regulation of Skip, but the role of Skip in metabolism was unknown. In this study, we mainly investigated whether Skip was involved in beige remodeling of subcutaneous white preadipocytes as well as in lipid metabolism of differentiated beige adipocytes. The results showed that in high fat diet-induced obesity mice, the protein levels of Skip in subcutaneous and visceral white adipose as well as in brown adipose were all down-regulated, especially in subcutaneous white adipose. Then we cultured subcutaneous adipose derived-stem cells (ADSCs) and found knock-down of Skip (siSkip) inhibited the expressions of thermogenic adipose specific genes including PRDM16 and UCP1 in both undifferentiated ADSCs and differentiated beige adipocytes, which could abolish the effects of BTM-0512 on beige remodeling. We further observed that siSkip affected multiple rate-limiting enzymes in lipid metabolism. The expressions of ACC, GPAT-1, HSL and ATGL were down-regulated, while CPT1α expression was up-regulated by siSkip. The expression of AMPK was also decreased by siSkip. In conclusion, our study demonstrated that Skip might play an important role in the beige remodeling of white adipocytes as well as lipid metabolism of beige adipose.
Assuntos
Tecido Adiposo Bege/metabolismo , Metabolismo dos Lipídeos , Monoéster Fosfórico Hidrolases/metabolismo , Sirtuína 1/metabolismo , Estilbenos/farmacologia , Tecido Adiposo Bege/efeitos dos fármacos , Animais , Diferenciação Celular/efeitos dos fármacos , Diferenciação Celular/genética , Dieta , Regulação para Baixo/efeitos dos fármacos , Regulação para Baixo/genética , Metabolismo dos Lipídeos/efeitos dos fármacos , Metabolismo dos Lipídeos/genética , Masculino , Camundongos Endogâmicos C57BL , Obesidade/genética , Monoéster Fosfórico Hidrolases/genética , Células-Tronco/citologia , Células-Tronco/efeitos dos fármacos , Células-Tronco/metabolismo , Termogênese/efeitos dos fármacos , Termogênese/genética , Proteína Desacopladora 1/metabolismoRESUMO
The two-dimensional counterpart of diamond, diamane, has attracted increasing interest due to its potentially distinctive properties. In this paper, diamanes anchored with different anion groups have been systematically studied with density functional theory (DFT) for the first time. Among them 12 conformers are confirmed to be stable and present direct semiconductor features with bandgaps ranging from 2.527 eV to 4.153 eV, and the in-plane stiffness is larger than that of graphene. Moreover, the electron carrier mobility of chair2-F is exceptionally high at 16546.713 cm2 V-1 s-1 along the y-direction, which is remarkably larger than that of diamond; and N-, B-doped boat2-H can be doped to have n-, p-type conductivity with a moderate activation energy of 0.34 and 0.37 eV, respectively. This work suggests that functionalized diamanes are promising for electronic devices and engineering materials.
RESUMO
Our previous study has suggested suppressor of cytokine signaling 1 (SOCS1) is associated with clinical progression and functions as an oncogenic role to regulate cell proliferation and apoptosis in triple-negative breast cancer (TNBC). Several microRNA-messenger RNA (miRNA-mRNA) relationship databases show SOCS1 is identified as a direct target gene of miRNA-4458 (miR-4458). The purpose of this study was to study the relationship between miR-4458 and SOCS1 in TNBC. In our results, miR-4458 expression was decreased in TNBC tissues and cells compared with adjacent normal tissues and normal mammary epithelial cell line, respectively. Moreover, miR-4458 directly bound to SOCS1, and negatively regulated SOCS1 mRNA and protein expression. Furthermore, miR-4458 suppressed cell proliferation and promote cell apoptosis through regulating SOCS1 in TNBC. Besides, levels of miR-4458 expression in patients with advanced clinical stage were obviously lower than in patients with early clinical stage. In conclusion, miR-4458 mediates SOCS1 to play a tumor-suppressive role in TNBC.
Assuntos
Apoptose/genética , Proliferação de Células/genética , Regulação Neoplásica da Expressão Gênica , MicroRNAs/genética , Proteína 1 Supressora da Sinalização de Citocina/genética , Neoplasias de Mama Triplo Negativas/genética , Regiões 3' não Traduzidas/genética , Sequência de Bases , Linhagem Celular , Linhagem Celular Tumoral , Sobrevivência Celular/genética , Feminino , Humanos , Estadiamento de Neoplasias , Homologia de Sequência do Ácido Nucleico , Neoplasias de Mama Triplo Negativas/patologiaRESUMO
Calcium homeostasis in osteoblasts plays fundamental roles in the physiology and pathology of bone tissue. Various types of mechanical stimuli promote osteogenesis and increase bone formation elicit increases in intracellular-free calcium concentration in osteoblasts. However, whether microgravity, a condition of mechanical unloading, exerts an influence on intracellular-free calcium concentration in osteoblasts or what mechanisms may underlie such an effect are unclear. Herein, we show that simulated microgravity reduces intracellular-free calcium concentration in primary mouse osteoblasts. In addition, simulated microgravity substantially suppresses the activities of L-type voltage-sensitive calcium channels, which selectively allow calcium to cross the plasma membrane from the extracellular space. Moreover, the functional expression of ryanodine receptors and inositol 1,4,5-trisphosphate receptors, which mediate the release of calcium from intracellular storage, decreased under simulated microgravity conditions. These results suggest that simulated microgravity substantially reduces intracellular-free calcium concentration through inhibition of calcium channels in primary mouse osteoblasts. Our study may provide a novel mechanism for microgravity-induced detrimental effects in osteoblasts, offering a new avenue to further investigate bone loss induced by mechanical unloading.
Assuntos
Canais de Cálcio/efeitos dos fármacos , Cálcio/metabolismo , Osteoblastos/efeitos da radiação , Simulação de Ausência de Peso , Animais , Bloqueadores dos Canais de Cálcio/farmacologia , Humanos , Camundongos , Osteoblastos/efeitos dos fármacos , Osteogênese/efeitos da radiação , Cultura Primária de CélulasRESUMO
Trichloroethene (TCE), a common environmental toxicant and widely used industrial solvent, has been implicated in the development of various autoimmune diseases (ADs). Although oxidative stress has been involved in TCE-mediated autoimmunity, the molecular mechanisms remain to be fully elucidated. These studies were, therefore, aimed to further explore the contribution of oxidative stress to TCE-mediated autoimmune response by specifically assessing the role of oxidative DNA damage, its repair enzyme poly(ADP-ribose)polymerase-1 (PARP-1) and apoptosis. To achieve this, groups of female MRL +/+ mice were treated with TCE, TCE plus N-acetylcysteine (NAC) or NAC alone (TCE, 10â¯mmol/kg, i.p., every 4th day; NAC, 250â¯mg/kg/day in drinking water) for 6â¯weeks. TCE treatment led to significantly higher levels of 8-hydroxy-2'-deoxyguanosine (8-OHdG) in the livers compared to controls, suggesting increased oxidative DNA damage. TCE-induced DNA damage was associated with significant activation of PARP-1 and increases in caspase-3, cleaved caspase-8 and -9, and alterations in Bcl-2 and Bax in the livers. Moreover, the TCE-mediated alterations corresponded with remarkable increases in the serum anti-ssDNA antibodies. Interestingly, NAC supplementation not only attenuated elevated 8-OHdG, PARP-1, caspase-3, cleaved caspase-9, and Bax, but also the TCE-mediated autoimmune response supported by significantly reduced serum anti-ssDNA antibodies. These results suggest that TCE-induced activation of PARP-1 followed by increased apoptosis presents a novel mechanism in TCE-associated autoimmune response and could potentially lead to development of targeted preventive and/or therapeutic strategies.
Assuntos
Autoimunidade/efeitos dos fármacos , Poli(ADP-Ribose) Polimerase-1/fisiologia , Solventes/toxicidade , Tricloroetileno/toxicidade , 8-Hidroxi-2'-Desoxiguanosina , Acetilcisteína/farmacologia , Animais , Anticorpos Antinucleares/sangue , Apoptose/efeitos dos fármacos , Dano ao DNA , Desoxiguanosina/análogos & derivados , Desoxiguanosina/metabolismo , Feminino , Fígado/efeitos dos fármacos , Fígado/metabolismo , Camundongos Knockout , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Proteína X Associada a bcl-2/metabolismoRESUMO
Cryptosporidium spp., Giardia duodenalis, and Enterocytozoon bieneusi are common gastrointestinal pathogens in humans and animals. Little is known about them and the range of species/assemblages/genotypes occurring in domestic pigs in China. Here, we present data on the occurrence and molecular diversity of these pathogens detected in the feces from farms in Henan, central China. Of 897 fecal samples tested, 28 (3.1%), 15 (1.7%), and 408 (45.5%) samples were positive for Cryptosporidium, G. duodenalis, and E. bieneusi, respectively. Cryptosporidium and G. duodenalis were most frequently detected in piglets, while E. bieneusi was markedly more prevalent in fattening pigs. Sequence analysis of SSU rRNA gene revealed that positive Cryptosporidium strains belonged to C. suis (n = 18) and C. scrofarum (n = 10). Giardia duodenalis assemblages E (n = 9), assemblages A (n = 3), and assemblages C (n = 3) were characterized based on the sequence analysis of tpi gene. Thirteen E. bieneusi genotypes comprising four novel (pigHN-I to pigHN-IV) and nine known (EbpC, EbpA, pigEbITS5, LW1, H, CM8, G, CHG19, and CHS5) genotypes were identified by ITS sequence analysis of a large proportion (n = 200) of E. bieneusi-positive samples. EbpC was the most frequent genotype, detected in 60 specimens. All 13 genotypes identified in this study clustered in zoonotic Group 1. The findings indicate that the presence of zoonotic species/assemblages/genotypes of these pathogens poses a threat to public health, suggesting that pigs in Henan province could be a significant source of human infection and water pollution.
Assuntos
Cryptosporidium/genética , Enterocytozoon/genética , Giardia lamblia/genética , Doenças dos Suínos/parasitologia , Zoonoses/parasitologia , Animais , Animais Domésticos , China/epidemiologia , Cryptosporidium/classificação , Cryptosporidium/isolamento & purificação , Cryptosporidium/patogenicidade , DNA de Protozoário , Enterocytozoon/classificação , Enterocytozoon/isolamento & purificação , Enterocytozoon/patogenicidade , Fezes/parasitologia , Genes de Protozoários/genética , Genes de RNAr/genética , Genótipo , Giardia lamblia/classificação , Giardia lamblia/isolamento & purificação , Giardia lamblia/patogenicidade , Prevalência , Análise de Sequência de DNA , Suínos , Doenças dos Suínos/epidemiologia , Zoonoses/epidemiologiaRESUMO
Tetrachloroethene (perchloroethylene, PCE), an ubiquitous environmental contaminant, has been implicated in inducing autoimmunity/autoimmune diseases (ADs), including systemic lupus erythematosus (SLE) and scleroderma in humans. However, experimental evidence suggesting the potential of PCE in mediating autoimmunity is lacking. This study was, therefore, undertaken to explore PCE's potential in inducing/exacerbating an autoimmune response. Six-week old female MRL+/+ mice, in groups of 6 each, were treated with PCE (0.5mg/ml) via drinking water for 12, 18 and 24weeks and markers of autoimmunity and oxidative stress were evaluated. PCE exposure led to significant increases in serum anti-nuclear antibodies (ANA), anti-dsDNA and anti-scleroderma-70 (anti-Scl-70) antibodies at 18weeks and, to a greater extent at 24weeks, suggesting that PCE exposure exacerbated autoimmunity in our animal model. The increases in autoantibodies were associated with time-dependent increases in malondialdehyde (MDA)-protein adducts and their antibodies, as well as significantly decreased levels of antioxidants GSH and SOD. The splenocytes isolated from mice treated with PCE for 18 and 24weeks showed greater Th17 cell proliferation and increased release of IL-17 in culture supernatants following stimulation with MDA-mouse serum albumin adducts, suggesting that MDA-modified proteins may act as an immunologic trigger by activating Th17 cells and contribute to PCE-mediated autoimmunity. Our studies thus provide an experimental evidence that PCE induces/exacerbates an autoimmune response and lipid-derived aldehydes (such as MDA) contribute to this response.
Assuntos
Autoimunidade/efeitos dos fármacos , Malondialdeído/metabolismo , Solventes/toxicidade , Tetracloroetileno/toxicidade , Animais , Anticorpos/sangue , Proliferação de Células/efeitos dos fármacos , Modelos Animais de Doenças , Feminino , Glutationa/sangue , Interleucina-17/metabolismo , Lipídeos , Lúpus Eritematoso Sistêmico , Camundongos , Ligação Proteica , Escleroderma Sistêmico , Baço/citologia , Superóxido Dismutase/sangue , Células Th17/efeitos dos fármacosRESUMO
RATIONALE: Necrosis is one of the main forms of cardiomyocyte death in heart disease. Recent studies have demonstrated that certain types of necrosis are regulated and programmed dependent on the activation of receptor-interacting serine/threonine-protein kinase (RIPK) 1 and 3 which may be negatively regulated by Fas-associated protein with death domain (FADD). In addition, microRNAs and long noncoding RNAs have been shown to play important roles in various biological processes recently. OBJECTIVE: The purpose of this study was to test the hypothesis that microRNA-103/107 and H19 can participate in the regulation of RIPK1- and RIPK3-dependent necrosis in fetal cardiomyocyte-derived H9c2 cells and myocardial infarction through targeting FADD. METHODS AND RESULTS: Our results show that FADD participates in H2O2-induced necrosis by influencing the formation of RIPK1 and RIPK3 complexes in H9c2 cells. We further demonstrate that miR-103/107 target FADD directly. Knockdown of miR-103/107 antagonizes necrosis in the cellular model and also myocardial infarction in a mouse ischemia/reperfusion model. The miR-103/107-FADD pathway does not participate in tumor necrosis factor-α-induced necrosis. In exploring the molecular mechanism by which miR-103/107 are regulated, we show that long noncoding RNA H19 directly binds to miR-103/107 and regulates FADD expression and necrosis. CONCLUSIONS: Our results reveal a novel myocardial necrosis regulation model, which is composed of H19, miR-103/107, and FADD. Modulation of their levels may provide a new approach for preventing myocardial necrosis.
Assuntos
Proteína de Domínio de Morte Associada a Fas/metabolismo , MicroRNAs/metabolismo , Infarto do Miocárdio/metabolismo , Traumatismo por Reperfusão Miocárdica/metabolismo , Miócitos Cardíacos/metabolismo , Animais , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Proteína de Domínio de Morte Associada a Fas/genética , Células HEK293 , Humanos , Peróxido de Hidrogênio/toxicidade , Masculino , Camundongos Endogâmicos C57BL , MicroRNAs/genética , Infarto do Miocárdio/genética , Infarto do Miocárdio/patologia , Infarto do Miocárdio/prevenção & controle , Traumatismo por Reperfusão Miocárdica/genética , Traumatismo por Reperfusão Miocárdica/patologia , Traumatismo por Reperfusão Miocárdica/prevenção & controle , Miócitos Cardíacos/efeitos dos fármacos , Miócitos Cardíacos/patologia , Necrose , Oligonucleotídeos/administração & dosagem , Proteínas Serina-Treonina Quinases/metabolismo , Interferência de RNA , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Ratos , Proteína Serina-Treonina Quinases de Interação com Receptores/metabolismo , Transdução de Sinais , Transfecção , Fator de Necrose Tumoral alfa/toxicidadeRESUMO
Polyhedral borane derivatives have been utilized in the treatment of boron neuron capture therapy (BNCT) for brain glioma, and much attention has been paid to search excellent biocompatible boron-rich composites for effective cancer BNCT therapy. In this study, we have exploited the self-assembly of the gold nanoclusters with carborane amino derivatives (GNCs-CB) for the precise bioimaging of cancer cells and targeted delivery of this carborane compound to the tumors. Our observations demonstrate that the GNCs-CB can readily realize accurate tumor imaging and long-term accumulation in tumor sites by EPR effect and nanometer size effect, and thus efficiently implement tumor-targeting delivery of the carborane derivative and facilitate the real-time fluorescent visualization monitoring of the carborane targeted delivery process. This makes it possible to realize the accurate location of the tumor by the carborane derivative and reduce the damage to normal tissues in the process of boron neutron capture therapy through imaging guided treatment.
Assuntos
Compostos de Boro/química , Ouro/química , Nanoconjugados/química , Neoplasias/diagnóstico por imagem , Imagem Óptica/métodos , Animais , Corantes Fluorescentes/química , Corantes Fluorescentes/farmacocinética , Células HeLa , Humanos , Camundongos , Camundongos Nus , Nanoconjugados/efeitos adversosRESUMO
Aniline exposure is associated with toxicity to the spleen, however, early molecular events in aniline-induced cell cycle progression in the spleen remain unknown. MicroRNAs (miRNAs) have been implicated in tumor development by modulating key cell cycle regulators and controlling cell proliferation. This study was, therefore, undertaken on the expression of miRNAs, regulation of cyclins and cyclin-dependent kinases (CDKs) in an experimental condition that precedes a tumorigenic response. Male SD rats were treated with aniline (1 mmol/kg/day by gavage) for 7 days, and expression of miRNAs, cyclins and CDKs in rat spleens were analyzed. Microarray and/or qPCR analyses showed that aniline exposure led to significantly decreased miRNA expression of let-7a, miR-24, miR-34c, miR-100, miR-125b, and greatly increased miR-181a. The aberrant expression of miRNAs was associated with significantly increased protein expression of cyclins A, B1, D3 and E. Furthermore, remarkably enhanced expression of CDKs like CDK1, CDK2, CDK4, CDK6, especially p-CDK1 and p-CDK2 as well as alternations in the expression of pRB, p27, and CDC25A in the spleens of aniline-treated rats was also observed. The data suggest that aniline exposure leads to aberrant expression of miRNAs in the spleen which could be important in the regulation of cell cycle proteins. Our findings, thus, provide new insight into the role of miRNAs in cell cycle progression, which may contribute to aniline-induced tumorigenic response in the spleen.
Assuntos
Compostos de Anilina/toxicidade , Carcinógenos Ambientais/toxicidade , Ciclo Celular/efeitos dos fármacos , Regulação da Expressão Gênica/efeitos dos fármacos , MicroRNAs/antagonistas & inibidores , Intoxicação/metabolismo , Baço/efeitos dos fármacos , Animais , Análise por Conglomerados , Quinases Ciclina-Dependentes/química , Quinases Ciclina-Dependentes/genética , Quinases Ciclina-Dependentes/metabolismo , Ciclinas/agonistas , Ciclinas/genética , Ciclinas/metabolismo , Indução Enzimática/efeitos dos fármacos , Perfilação da Expressão Gênica , Masculino , MicroRNAs/metabolismo , Intoxicação/patologia , RNA Mensageiro/metabolismo , Distribuição Aleatória , Ratos Sprague-Dawley , Reprodutibilidade dos Testes , Baço/metabolismo , Baço/patologiaRESUMO
Xylanase XynG1-1 from Paenibacillus campinasensis G1-1 consists of a catalytic domain (CD), a family 6_36 carbohydrate-binding module which is a xylan-binding domain (XBD), and a linker sequence (LS)between them. The structure of XynG1-3 from Bacillus pumilus G1-3 consists only of a CD. To investigate the functions and properties of the XBD and LS of XynG1-1, two truncated forms (XynG1-1CDL, XynG1-1CD) and three fusion derivatives (XynG1-3CDL, XynG1-3CDX and XynG1-3CDLX) were constructed and biochemically characterized. The optimum conditions for the catalytic activity of mutants of XynG1-1 and XynG1-3 were 60 °C and pH 7.0, and 55 °C and pH 8.0, respectively, the same as for the corresponding wild-type enzymes. XynGs with an XBD were stable over a broad temperature (30-80 °C)and pH range (4.0-11.0), respectively, on incubation for 3 h. Kinetic parameters (Km, kcat, kcat/Km) of XynGs were determined with soluble birchwood xylan and insoluble oat spelt xylan as substrates. XynGs with the XBD showed better affinities toward, and more efficient catalysis of hydrolysis of the insoluble substrate. The XBD had positive effects on thermostability and pH stability and a crucial function in the ability of the enzyme to bind and hydrolyze insoluble substrate. The LS had little effect on the overall stability of the xylanase and no relationship with affinities for soluble and insoluble substrates or catalytic efficiency.
Assuntos
Endo-1,4-beta-Xilanases/química , Endo-1,4-beta-Xilanases/metabolismo , Paenibacillus/enzimologia , Xilanos/metabolismo , Domínio Catalítico , Estabilidade Enzimática , Concentração de Íons de Hidrogênio , Hidrólise , Cinética , Modelos Moleculares , Solubilidade , Especificidade por Substrato , TemperaturaRESUMO
OBJECTIVE: To explore the levels of autoantibodies against AT1-receptor (AT1-AA) in hypertensive patients with acute coronary syndrome (ACS) and observe the in vitro effects of AT1-AA on resting tension of isolated anterior descending artery of vascular ring in male Wistar rats. METHODS: All patients were recruited from June 2007 to August 2008. There were hypertensive patients with ACS (n = 120), those with simple hypertension (n = 253) and those with simple ACS (n = 115). And the outpatients for health examination during the same period were selected as healthy control group (n = 188). The second extracellular loop amino acid sequences of peptides of ATI receptor was synthesized and used as antigen (AT1-Ag) and sialic acid-enzyme-linked immunosorbent assay (SA-ELISA) for detect the serum levels of AT1-AA. Microvascular ring tension technology was used to test the vascular loop resting tension of anterior descending coronary artery from rats induced by a high-fat diet. RESULTS: The positive rates of AT1-AA in patients with simple hypertension (35.2%) and those with simple ACS (30.4%) were significantly higher than those in healthy control group (7.2%, P < 0.01). And the positive rate of AT1-AA in hypertensive patients with ACS (43.3%) was significantly higher than that in those with simple hypertension (35.2%, P < 0.05) and that in healthy control group (7.2%, P < 0.05).Furthermore, AT1-AA increased the vascular loop resting tension of anterior descending coronary artery rings in rats induced by a high-fat diet in a dose-dependant manner. And the vasoconstrictive action of AT1-AA was equal to 46.4% of AngII's action. And such an action was blocked by losartan and antigens. CONCLUSION: The level of AT1-AA increases markedly in hypertensive patients with ACS. And AT1-AA induces vasoconstrictive effects on anterior descending artery rings in rats induced by a high-fat diet.
Assuntos
Síndrome Coronariana Aguda , Hipertensão , Animais , Aorta , Autoanticorpos , Dieta Hiperlipídica , Ensaio de Imunoadsorção Enzimática , Humanos , Masculino , Ratos , Ratos Wistar , Receptor Tipo 1 de Angiotensina , VasoconstriçãoRESUMO
Herein we report the successful incorporation of a lactam as an amide replacement in the design of hepatitis C virus NS5B Site II thiophene carboxylic acid inhibitors. Optimizing potency in a replicon assay and minimizing potential risk for CYP3A4 induction led to the discovery of inhibitor 22a. This lead compound has a favorable pharmacokinetic profile in rats and dogs.
Assuntos
Antivirais/farmacologia , Ácidos Carboxílicos/farmacologia , Desenho de Fármacos , Inibidores Enzimáticos/farmacologia , RNA Polimerase Dependente de RNA/antagonistas & inibidores , Proteínas não Estruturais Virais/antagonistas & inibidores , Animais , Antivirais/síntese química , Antivirais/química , Ácidos Carboxílicos/síntese química , Ácidos Carboxílicos/química , Cães , Relação Dose-Resposta a Droga , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/química , Hepacivirus/efeitos dos fármacos , Hepacivirus/enzimologia , Lactamas/química , Estrutura Molecular , RNA Polimerase Dependente de RNA/metabolismo , Ratos , Relação Estrutura-Atividade , Tiofenos/química , Proteínas não Estruturais Virais/metabolismoRESUMO
The transglutaminase (BTG) from Bacillus subtilis is considered to be a new type of transglutaminase for the food industry. Given that the BTG gene only encodes a mature peptide, the expression of BTG in heterologous microbial hosts could affect their normal growth due to BTG's typical transglutaminase activity which can catalyze cross-linking of proteins in the cells. Therefore, we developed a novel approach to suppress BTG activity and reduce the toxicity on microbial hosts, thus improving BTG yield. Genes encoding the respective regions of transglutaminase propeptide from seven species of Streptomyces were fused to the N-terminal of the BTG gene to produce fusion proteins. We found that all the fused propeptides could suppress BTG activity. Importantly, BTG activity could be completely restored after the removal of the propeptides by proteolytic cleavage. Of the seven propeptides tested, the propeptide proD from Streptomyces caniferus had the strongest suppressive effect on BTG activity (70 % of the activity suppressed). Moreover, fusion protein proD-BTG (containing proD) also exhibited the highest yield which was more than twofold of the expression level of BTG in an active form in Escherichia coli. Secretion expression of BTG and proD-BTG in Corynebacterium glutamicum further showed that our novel approach was suitable for the efficient BTG expression, thus providing a valuable platform for further optimization of large-scale BTG production.
Assuntos
Bacillus subtilis/enzimologia , Reatores Biológicos , Precursores Enzimáticos/genética , Proteínas Recombinantes de Fusão/biossíntese , Streptomyces/genética , Transglutaminases/biossíntese , Sequência de Aminoácidos , Corynebacterium glutamicum , Eletroforese em Gel de Poliacrilamida , Precursores Enzimáticos/metabolismo , Escherichia coli , Microbiologia Industrial/métodos , Dados de Sequência Molecular , Plasmídeos/genética , Corantes de Rosanilina , Streptomyces/enzimologia , Transglutaminases/antagonistas & inibidores , Transglutaminases/genéticaRESUMO
The extreme process condition of high temperature and high alkali limits the applications of most of natural xylanases in pulp and paper industry. Recently, various methods of protein engineering have been used to improve the thermal and alkalic tolerance of xylanases. In this work, directed evolution and site-directed mutagenesis were performed to obtain a mutant xylanase improved both on alkali stability and thermostability from the native Paenibacillus campinasensis Family-11 xylanase (XynG1-1). Mutant XynG1-1B43 (V90R/P172H) with two units increased in the optimum pH (pH 7.0-pH 9.0) and significant improvement on alkali stability was selected from the second round of epPCR library. And the further thermoduric mutant XynG1-1B43cc16 (V90R/P172H/T84C-T182C/D16Y) with 10 °C increased in the optimum temperature (60-70 °C) was then obtained by introducing a disulfide bridge (T84C-T182C) and a single amino acid substitution (D16Y) to XynG1-1B43 using site-directed mutagenesis. XynG1-1B43cc16 also showed higher thermostability and catalytic efficiency (k cat /K m ) than that of wild-type (XynG1-1) and XynG1-1B43. The attractive improved properties make XynG1-1B43cc16 more suitable for bioleaching of cotton stalk pulp under the extreme process condition of high temperature (70 °C) and high alkali (pH 9.0).
Assuntos
Endo-1,4-beta-Xilanases/química , Endo-1,4-beta-Xilanases/genética , Paenibacillus/enzimologia , Álcalis/química , Sequência de Aminoácidos , Substituição de Aminoácidos , Evolução Molecular Direcionada , Dissulfetos/química , Endo-1,4-beta-Xilanases/metabolismo , Estabilidade Enzimática/genética , Biblioteca Gênica , Temperatura Alta , Concentração de Íons de Hidrogênio , Dados de Sequência Molecular , Mutagênese Sítio-Dirigida , Alinhamento de SequênciaRESUMO
OBJECTIVE: To explore the effect of the autoantibody against the ß3-adrenoceptor on rats with experimental heart failure. METHOD: The peptide corresponding to the sequence of ß3 adrenoceptor was synthesized to actively immunize the rats, ELISA was used to detect the serum level of autoantibody against the ß3-adrenoceptor (ß3AA). Total IgGs were extracted from the serum containing ß3AA in immunized rats. Aortic banding surgery was used to establish the heart failure model in male Wistar rats and rats were divided into the sham group (n = 8), heart failure group(n = 8),ß3AA-immunized heart failure group (HF+ß3AA, n = 8) and corresponding negative IgG-immunized heart failure group (HF+ IgG, n = 8).In 6 weeks and 8 weeks after aortic banding surgery, the serum levels of NT-pro brain natriuretic peptide (NT-proBNP) were assayed with ELISA assay and cardiac function was assessed by echocardiography. RESULTS: ß3AA was used to immunize rat with heart failure, the serum level of ß3AA was stable at 50 days post immunization. At 8 weeks after aortic banding surgery, heart failure group showed significantly increased LVEDD [(6.92 ± 0.22) mm vs.(5.62 ± 0.19) mm, P < 0.001], LVESD [(4.63 ± 0.23) mm vs.(3.50 ± 0.20) mm, P < 0.01] and IVS [(2.44 ± 0.06) mm vs.(2.28 ± 0.05) mm, P < 0.05], and decreased LVEF[(62.07 ± 3.99)% vs.(79.63 ± 3.02)%, P < 0.01] and LVFS [(31.46 ± 3.22)% vs.(43.65 ± 2.68) %, P < 0.05] compared with the sham group.HF+ß3AA IgG group showed decreased LVEDD [(6.07 ± 0.30) mm vs.(6.92 ± 0.24) mm, P < 0.05] and LVESD [(3.92 ± 0.22) mm vs.(4.68 ± 0.23) mm, P < 0.05], and higher LVEF [(70.29 ± 1.78)% vs.(61.95 ± 3.03)%, P < 0.05] and LVFS [(38.08 ± 2.32)% vs.(30.50 ± 1.82)%, P < 0.05] compared to the HF+ IgG group.In addition, compared with the HF+ IgG group, HF+ß3AA IgG group showed decreased serum levels of NT-proBNP [(196.43 ± 6.56) pg/ml vs.(242.13 ± 7.86) pg/ml, P < 0.01]. CONCLUSION: Our results demonstrate that ß3AA can improve cardiac function and reduce the serum levels of NT-proBNP in rat with heart failure.
Assuntos
Autoanticorpos/uso terapêutico , Cardiotônicos/uso terapêutico , Insuficiência Cardíaca/tratamento farmacológico , Receptores Adrenérgicos beta 3/imunologia , Animais , Modelos Animais de Doenças , Masculino , Peptídeo Natriurético Encefálico/sangue , Fragmentos de Peptídeos/sangue , Ratos , Ratos WistarRESUMO
PURPOSE: The role of dual-specificity phosphatase-5 (DUSP5) in BRAF-mutant thyroid cancers remains unclear. The aims of this study are to investigate the role of DUSP5 in BRAF-mutant thyroid cancer cells, explore its value in the diagnosis and evaluate therapeutic potential of targeting DUSP5 combined with sorafenib for BRAF-mutant thyroid cancer patients. METHODS: The role of DUSP5 in thyroid cancer cells was determined by a series of in vitro and in vivo experiments. Underlying mechanisms were explored by western blotting analysis. The diagnostic value of combination detection of DUSP5 expression and BRAFV600E mutation was evaluated using ROC curve. RESULTS: Knocking down DUSP5 in BRAF-mutant thyroid cancer cells significantly inhibited colony formation, cell migration and invasion, meanwhile, induced cell cycle arrest and cell apoptosis. Moreover, inhibition of DUSP5 improved the anti-tumor efficacy of sorafenib both in vitro and in vivo. Besides, combination detection of DUSP5 expression and BRAFV600E mutation showed much more accuracy in preoperative diagnosis of thyroid cancer. CONCLUSIONS: Our data demonstrate an oncogenic role of DUSP5 in BRAF-mutant thyroid cancer cells, and combined analysis of its expression and BRAFV600E mutation can accurately diagnose thyroid cancer. In addition, inhibition of DUSP5 improves the response of BRAF-mutant thyroid cancer cells to sorafenib.