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1.
Small ; : e2310801, 2024 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-38308086

RESUMO

Lithium-sulfur (Li-S) batteries show extraordinary promise as a next-generation battery technology due to their high theoretical energy density and the cost efficiency of sulfur. However, the sluggish reaction kinetics, uncontrolled growth of lithium sulfide (Li2 S), and substantial Li2 S oxidation barrier cause low sulfur utilization and limited cycle life. Moreover, these drawbacks get exacerbated at high current densities and high sulfur loadings. Here, a heterostructured WOx /W2 C nanocatalyst synthesized via ultrafast Joule heating is reported, and the resulting heterointerfaces contribute to enhance electrocatalytic activity for Li2 S oxidation, as well as controlled Li2 S deposition. The densely distributed nanoparticles provide abundant binding sites for uniform deposition of Li2 S. The continuous heterointerfaces favor efficient adsorption and promote charge transfer, thereby reducing the activation barrier for the delithiation of Li2 S. These attributes enable Li-S cells to deliver high-rate performance and high areal capacity. This study provides insights into efficient catalyst design for Li2 S oxidation under practical cell conditions.

2.
Cell Immunol ; 385: 104677, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36746070

RESUMO

BACKGROUND: Postoperative ileus (POI) is characterized by the activation of inflammation triggered by tissue damage. Damage-associated molecular patterns (DAMPs) reportedly induce local inflammation after injury. However, the impact of DAMPs on intestinal resident lymphocytes during POI remains poorly elucidated. METHODS: POI in mice was induced via intestinal manipulation (IM). The concentration of nicotinamide adenine dinucleotide (NAD) was detected after IM. The gastrointestinal motility of the mice was assessed after IM or NAD injection. Cytokine production and calcium influx in T cells were investigated after NAD stimulation using flow cytometry. RESULTS: The concentration of extracellular NAD significantly increased after IM administration, and NAD directly impaired gastrointestinal motility. Intraperitoneal injection of NAD promoted the expression of TNF-α in intestinal CD8+ and CD4+ T cells, but only IFN-γ production by CD8+ T cells was significantly promoted by NAD injection. Granzyme B production in CD8+ and CD4+ T cells decreased after administration. Concordantly, the same results were observed in NAD stimulation of intestinal CD3+ T cells in vitro. Blocking the P2X7R-related membrane enzyme ART2.2 significantly diminished the pro-inflammatory effect of NAD. CONCLUSION: IM includes the release of NAD derived from damaged tissues, consequently promoting pro-inflammatory cytokine production in intestinal CD4+ and CD8+ T lymphocytes. NAD-induced intestinal T cells activation may be associated with POI progression in the mouse.


Assuntos
Íleus , NAD , Camundongos , Animais , Íleus/metabolismo , Inflamação/metabolismo , Complicações Pós-Operatórias/metabolismo , Citocinas , Linfócitos T CD8-Positivos/metabolismo , Linfócitos T CD4-Positivos/metabolismo
3.
Water Res ; 203: 117520, 2021 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-34392040

RESUMO

Surface modification of nanofiltration (NF) membranes has great potential to improve the removal of organic micropollutants (OMs) by NF membranes. This study used polydopamine (PDA) as a model coating to comprehensively link the changes in membrane properties with the changes in transmission of 34 OMs. The membrane characterization demonstrated that a thicker, denser, and more hydrophilic PDA coating can be achieved by increasing the PDA deposition time from 0.5 to 4 hours. Overall, the transmissions of target OMs were reduced by PDA-coated NF membranes compared to unmodified NF membranes. The neutral hydrophobic compounds showed lower transmissions for longer PDA coating (PDA4), while the neutral hydrophilic compounds tended to show lower transmissions for shorter PDA coating (PDA0.5). To explain this, competing effects provided by the PDA coatings are proposed including sealing defects, inducing cake-enhanced concentration polarization in the coating layer for neutral hydrophilic compounds, and weakened hydrophobic adsorption for neutral hydrophobic compounds. For charged compounds, PDA4 with the greatest negative charge among the PDA-coated membranes showed the lowest transmission. Depending on the molecular size and hydrophilicity of the compounds, the transmission of OMs by the PDA4 coating could be reduced by 70% with only a 26.4% decline in water permeance. The correlations and mechanistic insights provided by this work are highly useful for designing membranes with specific surface properties via surface modification to improve the removal of OMs without compromising water production.


Assuntos
Purificação da Água , Adsorção , Interações Hidrofóbicas e Hidrofílicas , Membranas Artificiais , Propriedades de Superfície
4.
Materials (Basel) ; 14(7)2021 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-33805355

RESUMO

In the selective laser melting process, metal powder melted by the laser heat source generates large instantaneous energy, resulting in transient high temperature and complex stress distribution. Different temperature gradients and anisotropy finally determine the microstructure after melting and affect the build quality and mechanical properties as a result. It is important to monitor and investigate the temperature and stress distribution evolution. Due to the difficulties in online monitoring, finite element methods (FEM) are used to simulate and predict the building process in real time. In this paper, a thermo-mechanical coupled FEM model is developed to predict the thermal behaviors of the melt pool by using Gaussian moving heat source. The model could simulate the shapes of the melt pool, distributions of temperature and stress under different process parameters through FEM. The influences of scanning speed, laser power, and spot diameter on the distribution of the melt pool temperature and stress are investigated in the SLM process of Al6063, which is widely applied in aerospace, transportation, construction and other fields due to its good corrosion resistance, sufficient strength and excellent process performance. Based on transient analysis, the relationships are identified among these process parameters and the melt pool morphology, distribution of temperature and thermal stress. It is shown that the maximum temperature at the center point of the scanning tracks will gradually increase with the increment of laser power under the effect of thermal accumulation and heat conduction, as the preceded scanning will preheat the subsequent scanning tracks. It is recommended that the parameters with optimized laser power (P = 175-200 W), scanning speed (v = 200-300 mm/s) and spot diameter (D = 0.1-0.15 mm) of aluminum alloy powder can produce a high building quality of the SLM parts under the pre-set conditions.

5.
Food Chem ; 349: 129143, 2021 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-33581432

RESUMO

Millions of tons of collagen-rich bovine bone are produced as byproducts of the consumption of beef. Hydrolyzing bovine bone collagen (BBC) is an effective measure for both increasing its added value and protecting the environment. In this study, a kind of recombinant bacterial collagenase mining from Bacillus cereus was successfully performed and applied to hydrolyze BBC to collagen-soluble peptides (CPP). Response surface methodology (RSM) was applied to optimize the processing conditions of antioxidant CPP, attaining a distinguished ABTS free radical scavenging activity of 99.21 ± 0.35% while keeping DPPH free radical scavenging activity and reducing power at high levels under the optimal condition. Furthermore, we identified five new antioxidant peptides by LC-MS/MS with typical collagen repeated Gly-Xaa-Yaa sequence units within the CPP. These results suggest that our recombinant collagenase is a powerful tool for degrading collagen and the CPP are promising candidates for antioxidant and related functional food applications.


Assuntos
Bacillus cereus/enzimologia , Osso e Ossos/química , Colágeno/química , Colagenases/metabolismo , Fragmentos de Peptídeos/metabolismo , Fragmentos de Peptídeos/farmacologia , Proteínas Recombinantes/metabolismo , Animais , Antioxidantes/metabolismo , Antioxidantes/farmacologia , Bovinos , Hidrólise
6.
Mol Psychiatry ; 26(6): 2363-2379, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-32317715

RESUMO

FAM19A5/TAFA5 is a member of the family with sequence similarity 19 with unknown function in emotional and cognitive regulation. Here, we reported that FAM19A5 was highly expressed in the embryonic and postnatal mouse brain, especially in the hippocampus. Behaviorally, genetic deletion of Fam19a5 resulted in increased depressive-like behaviors and impaired hippocampus-dependent spatial memory. These behavioral alterations were associated with the decreased expression of α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptors and N-methyl-D-aspartic acid receptors, as well as significantly reduced glutamate release and neuronal activity in the hippocampus. Subsequently, these changes led to the decreased density of dendritic spines. In recent years, the roles of chronic stress participating in the development of depression have become increasingly clear, but the mechanism remains to be elucidated. We found that the levels of FAM19A5 in plasma and hippocampus of chronic stress-treated mice were significantly decreased whereas overexpression of human FAM19A5 selectively in the hippocampus could attenuate chronic stress-induced depressive-like behaviors. Taken together, our results revealed for the first time that FAM19A5 plays a key role in the regulation of depression and spatial cognition in the hippocampus. Furthermore, our study provided a new mechanism for chronic stress-induced depression, and also provided a potential biomarker for the diagnosis and a new strategy for the treatment of depression.


Assuntos
Depressão , Memória Espacial , Animais , Biomarcadores , Hipocampo , Camundongos , Estresse Psicológico , Ácido alfa-Amino-3-hidroxi-5-metil-4-isoxazol Propiônico
7.
Nat Commun ; 11(1): 5912, 2020 11 20.
Artigo em Inglês | MEDLINE | ID: mdl-33219235

RESUMO

The physiological homeostasis of gut mucosal barrier is maintained by both genetic and environmental factors and its impairment leads to pathogenesis such as inflammatory bowel disease. A cytokine like molecule, FAM3D (mouse Fam3D), is highly expressed in mouse gastrointestinal tract. Here, we demonstrate that deficiency in Fam3D is associated with impaired integrity of colonic mucosa, increased epithelial hyper-proliferation, reduced anti-microbial peptide production and increased sensitivity to chemically induced colitis associated with high incidence of cancer. Pretreatment of Fam3D-/- mice with antibiotics significantly reduces the severity of chemically induced colitis and wild type (WT) mice co-housed with Fam3D-/- mice phenocopy Fam3D-deficiency showing increased sensitivity to colitis and skewed composition of fecal microbiota. An initial equilibrium of microbiota in cohoused WT and Fam3D-/- mice is followed by an increasing divergence of the bacterial composition after separation. These results demonstrate the essential role of Fam3D in colon homeostasis, protection against inflammation associated cancer and normal microbiota composition.


Assuntos
Carcinogênese , Colo , Citocinas/metabolismo , Animais , Colite , Colo/metabolismo , Colo/microbiologia , Colo/patologia , Neoplasias Colorretais , Modelos Animais de Doenças , Microbioma Gastrointestinal , Inflamação , Doenças Inflamatórias Intestinais , Mucosa Intestinal/crescimento & desenvolvimento , Mucosa Intestinal/patologia , Camundongos , Proteínas Citotóxicas Formadoras de Poros/metabolismo
8.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 28(4): 1183-1188, 2020 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-32798396

RESUMO

OBJECTIVE: To detect the expression levels of FAM19A5 in patients with mantle cell lymphoma (MCL), and to determine the relationship between FAM19A5 and the prognosis of MCL patients. METHODS: Twenty-five MCL patients were choosen in the study, cytometric bead assay was used to detected the concentration of FAM19A5 in serum and immunohistochemical analysis were used to detect the expression levels of FAM19A5 in lymph nodes. The relationship of the FAM19A5 expression in serum and tissue were analyzed, the relationship of FAM19A5 and clinical characteristics of MCL patients, treatment and prognosis of MCL patients was analyzed. RESULTS: The average serum concentration of FAM19A5 in MCL patients was 90.55±38.24 (ng/ml), which was significantly higher than that in control (P=0.0461). The proportion of high, medium, and low expression of FAM19A5 in lymph nodes was 32%, 36% and 32%, respectively, which showed significant difference from that in control group (P=0.001). The expression of FAM19A5 in serum and lymph nodes showed significant correlation (r=0.8683,P=0.001). The serum concentration of FAM19A5 showed positive correlation with the proportion of Ki67 (P=0.0222, r=0.4554). The mean survival time without relapse/death of MCL patients with high, middle and low expression of FAM19A5 was 17, 27 and 37.5 months, respectively,which showed significant statistical difference (P=0.0360). ROC curve analysis showed that serum concentration of FAM19A5 could predict the therapeutic effect in MCL patients, the cut-off value was 91.49 ng/ml. The proportion of recurrent/death in AML patients with FAM19A5 >91.49 ng/ml was significantly higher than that in patients with FAM19A5<91.49 ng/ml (P=0.0156). CONCLUSION: The expression level of FAM19A5 is increased in MCL patient, and patients with high expression of FAM19A5 are more likely to relapse or die. FAM19A5 may be a new prognostic marker and potential therapeutic target for MCL.


Assuntos
Transplante de Células-Tronco Hematopoéticas , Leucemia Mieloide Aguda , Adulto , Humanos , Recidiva Local de Neoplasia , Prognóstico , Resultado do Tratamento , Tirosina Quinase 3 Semelhante a fms
9.
Biotechnol Bioeng ; 117(11): 3345-3355, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32678455

RESUMO

With the aggravation of environmental pollution and energy crisis, the sustainable microbial fermentation process of converting glycerol to 1,3-propanediol (1,3-PDO) has become an attractive alternative. However, the difficulty in the online measurement of glycerol and 1,3-PDO creates a barrier to the fermentation process and then leads to the residual glycerol and therefore, its wastage. Thus, in the present study, the four-input artificial neural network (ANN) model was developed successfully to predict the concentration of glycerol, 1,3-PDO, and biomass with high accuracy. Moreover, an ANN model combined with a kinetic model was also successfully developed to simulate the fed-batch fermentation process accurately. Hence, a soft sensor from the ANN model based on NaOH-related parameters has been successfully developed which cannot only be applied in software to solve the difficulty of glycerol and 1,3-PDO online measurement during the industrialization process, but also offer insight and reference for similar fermentation processes.


Assuntos
Técnicas de Cultura de Células/métodos , Clostridium butyricum/metabolismo , Fermentação/fisiologia , Redes Neurais de Computação , Propilenoglicóis , Reatores Biológicos/microbiologia , Meios de Cultura/análise , Meios de Cultura/química , Meios de Cultura/metabolismo , Glicerol/análise , Glicerol/metabolismo , Cinética , Propilenoglicóis/análise , Propilenoglicóis/metabolismo
10.
Appl Biochem Biotechnol ; 191(2): 893-903, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31912425

RESUMO

Quorum quenching (QQ) enzymes, which degrade signaling molecules so as to disrupt the quorum sensing signaling process, have drawn much attention as alternative antimicrobial agents. However, the screening methods for evolution of such enzymes through constructing genetic circuits remain a challenge for its relatively high false positive rates caused by the higher basal expression level of the naturally acquired promoter. Thus, we presented an improved genetic circuit by introducing an artificial hybrid promoter PluxI-lacO combining PlacO originated from lactose promoter with QS regulatory promoter PluxI to control the expression of reporter gene rfp. Herein, we investigated the effect of various expression strengths of suppressive protein LacI and signaling molecule AHL on the expression of rfp. We found that the effect AHL exerted on the expression of rfp outweighed that from IPTG. The results also demonstrated that our genetic circuit could achieve the lower basal expression level of reporter gene and could respond to the expression of AiiA. The resulting circuits show the potential for screening the evolved AiiA more efficiently by virtue of inherent low basal expression level.


Assuntos
Proteínas de Bactérias/genética , Regulação Bacteriana da Expressão Gênica , Percepção de Quorum/genética , Genes Bacterianos/genética , Metaloendopeptidases/genética , Regiões Promotoras Genéticas , Proteínas Repressoras , Transativadores
11.
J Hepatol ; 72(3): 506-518, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31813573

RESUMO

BACKGROUND & AIMS: C-C motif chemokine receptor 2 (CCR2) has been recognized as a promising target for the treatment of liver fibrosis. PC3-secreted microprotein (PSMP)/microseminoprotein (MSMP) is a novel chemotactic cytokine and its receptor is CCR2. In the present study we investigated the expression and role of PSMP in liver fibrosis/cirrhosis. METHODS: PSMP expression was studied in patients with fibrosis/cirrhosis and in 3 murine models of liver fibrosis, including mice treated with carbon tetrachloride (CCl4), bile-duct ligation, or a 5-diethoxycarbonyl-1,4-dihydrocollidine diet. The role of PSMP was evaluated in Psmp-/- mice and after treatment with a PSMP antibody in wild-type mice. The direct effects of PSMP on macrophages and hepatic stellate cells were studied in vitro. RESULTS: In this study, we found that PSMP was highly expressed in fibrotic/cirrhotic tissues from patients with different etiologies of liver disease and in the 3 experimental mouse models of fibrosis. Damage-associated molecular pattern molecules HMGB-1 and IL-33 induced hepatocytes to produce PSMP. PSMP deficiency resulted in a marked amelioration of hepatic injury and fibrosis. In CCl4-induced hepatic injury, the infiltration of macrophages and CCR2+ monocytes into the liver was significantly decreased in Psmp-/- mice. Consistent with the decreased levels of intrahepatic macrophages, proinflammatory cytokines were significantly reduced. Moreover, adeno-associated virus-8 vectors successfully overexpressing human PSMP in Psmp-/- mouse livers could reverse the attenuation of liver injury and fibrosis induced by CCl4 in a CCR2-dependent manner. Treatment with a specific PSMP-neutralizing antibody, 3D5, prevented liver injury and fibrosis induced by CCl4 in mice. At the cellular level, PSMP directly promoted M1 polarization of macrophages and activation of LX-2 cells. CONCLUSION: PSMP enhances liver fibrosis through its receptor, CCR2. PSMP is a potentially attractive therapeutic target for the treatment of patients with liver fibrosis. LAY SUMMARY: Our present study identifies the essential role of the protein PSMP for the development and progression of liver fibrosis in humans and mice. PSMP promotes liver fibrosis through inflammatory macrophage infiltration, polarization and production of proinflammatory cytokines, as well as direct activation of hepatic stellate cells via its receptor CCR2. A PSMP antibody can significantly reduce liver fibrosis development in vivo. These findings indicate that PSMP is a potential therapeutic target and its antibody is a potential therapeutic agent for the treatment of liver fibrosis.


Assuntos
Carcinoma Hepatocelular/metabolismo , Cirrose Hepática Experimental/metabolismo , Neoplasias Hepáticas/metabolismo , Proteínas de Neoplasias/deficiência , Receptores CCR2/deficiência , Receptores CCR2/metabolismo , Animais , Anticorpos Neutralizantes/uso terapêutico , Tetracloreto de Carbono/efeitos adversos , Carcinoma Hepatocelular/patologia , Polaridade Celular/genética , Células Cultivadas , Citocinas/biossíntese , Vetores Genéticos , Células Estreladas do Fígado/efeitos dos fármacos , Células Estreladas do Fígado/metabolismo , Humanos , Cirrose Hepática Experimental/induzido quimicamente , Cirrose Hepática Experimental/prevenção & controle , Neoplasias Hepáticas/patologia , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Masculino , Camundongos , Camundongos Knockout , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/imunologia , Proteínas de Neoplasias/farmacologia , Receptores CCR2/genética , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/genética , Resultado do Tratamento , Regulação para Cima
12.
FASEB J ; : fj201800020RRR, 2018 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-29799787

RESUMO

FAM19A1 is a member of the family with sequence similarity 19 with unknown function. FAM19A1 mRNA expression is restricted to the CNS. Here, we report that FAM19A1 is a classic secretory protein, and expression levels correlate with brain development, increasing from embryonic d 12.5, peaking between postnatal d (P)1 and P7 and decreasing at wk 8. The adult hippocampus is a region of FAM19A1 high expression. Recombinant FAM19A1 suppressed the proliferation and self-renewal of neural stem cells (NSCs) and altered the lineage progression of NSCs with promoted neuron differentiation and suppressed astrocyte differentiation. Although GPCR 1 (GPR1) has been reported to be expressed in the CNS, its functions in the brain remain unclear. We identified GPR1 to be a functional receptor for FAM19A1. FAM19A1 interacted with GPR1 via the N-terminal domain (GPR1-ND), and its NSC modulatory functions required the Rho-associated protein kinase (ROCK) /ERK1/2 and ROCK/signal transducer and activator of transcription 3 signaling pathways. GPR1-ND that selectively bound to FAM19A1 neutralized the effects of FAM19A1 on NSC functions. Taken together, our results show, for the first time to our knowledge, that FAM19A1 is a novel regulatory factor of the proliferation and differentiation of NSCs, and identified a novel mechanism by which GPCR mediates the effects of FAM19A1 on NSC functions that may be important for brain development and neurogenesis. Additional exploration of the functions of FAM19A1 and GPR1 in the CNS may broaden the range of therapeutic options available for major brain disorders.-Zheng, C., Chen, D., Zhang, Y., Bai, Y., Huang, S., Zheng, D., Liang, W., She, S., Peng, X., Wang, P., Mo, X., Song, Q., Lv, P., Huang, J., Ye, R. D., Wang, Y. FAM19A1 is a new ligand for GPR1 that modulates neural stem-cell proliferation and differentiation.

13.
Circulation ; 138(1): 48-63, 2018 07 03.
Artigo em Inglês | MEDLINE | ID: mdl-29453251

RESUMO

BACKGROUND: Obesity plays crucial roles in the development of cardiovascular diseases. However, the mechanisms that link obesity and cardiovascular diseases remain elusive. Compelling evidence indicates that adipokines play an important role in obesity-related cardiovascular diseases. Here, we found a new adipokine-named family with sequence similarity 19, member A5 (FAM19A5), a protein with unknown function that was predicted to be distantly related to the CC-chemokine family. We aimed to test whether adipose-derived FAM19A5 regulates vascular pathology on injury. METHODS: DNA cloning, protein expression, purification, and N-terminal sequencing were applied to characterize FAM19A5. Adenovirus infection and siRNA transfection were performed to regulate FAM19A5 expression. Balloon and wire injury were performed in vivo on the rat carotid arteries and mouse femoral arteries, respectively. Bioinformatics analysis, radioactive ligand-receptor binding assays, receptor internalization, and calcium mobilization assays were used to identify the functional receptor for FAM19A5. RESULTS: We first characterized FAM19A5 as a secreted protein, and the first 43 N-terminal amino acids were the signal peptides. Both FAM19A5 mRNA and protein were abundantly expressed in the adipose tissue but were downregulated in obese mice. Overexpression of FAM19A5 markedly inhibited vascular smooth muscle cell proliferation and migration and neointima formation in the carotid arteries of balloon-injured rats. Accordingly, FAM19A5 silencing in adipocytes significantly promoted vascular smooth muscle cell activation. Adipose-specific FAM19A5 transgenic mice showed greater attenuation of neointima formation compared with wild-type littermates fed with or without Western-style diet. We further revealed that sphingosine-1-phosphate receptor 2 was the functional receptor for FAM19A5, with a dissociation constant (Kd) of 0.634 nmol/L. Inhibition of sphingosine-1-phosphate receptor 2 or its downstream G12/13-RhoA signaling circumvented the suppressive effects of FAM19A5 on vascular smooth muscle cell proliferation and migration. CONCLUSIONS: We revealed that a novel adipokine, FAM19A5, was capable of inhibiting postinjury neointima formation via sphingosine-1-phosphate receptor 2-G12/13-RhoA signaling. Downregulation of FAM19A5 during obesity may trigger cardiometabolic diseases.


Assuntos
Tecido Adiposo/metabolismo , Citocinas/metabolismo , Músculo Liso Vascular/metabolismo , Neointima , Receptores de Lisoesfingolipídeo/metabolismo , Lesões do Sistema Vascular/metabolismo , Adipócitos/metabolismo , Animais , Sinalização do Cálcio , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Citocinas/genética , Modelos Animais de Doenças , Subunidades alfa G12-G13 de Proteínas de Ligação ao GTP/metabolismo , Células HEK293 , Humanos , Masculino , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Músculo Liso Vascular/lesões , Músculo Liso Vascular/patologia , Miócitos de Músculo Liso/metabolismo , Miócitos de Músculo Liso/patologia , Obesidade/genética , Obesidade/metabolismo , Comunicação Parácrina , Ratos Sprague-Dawley , Receptores de Lisoesfingolipídeo/genética , Receptores de Esfingosina-1-Fosfato , Técnicas de Cultura de Tecidos , Lesões do Sistema Vascular/genética , Lesões do Sistema Vascular/patologia , Proteína rhoA de Ligação ao GTP/metabolismo
14.
Biotechnol Bioeng ; 115(3): 684-693, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29105732

RESUMO

1,3-propanediol production by Clostridium butyricum is a low productivity process due to the long time seed cultivation and thus hinders its industrial scale production. In the present study, repeated batch fermentation coupled with activated carbon adsorption strategy was first established which conduced not only to saving the time of seed cultivation and enhancing the productivity, but also to reducing the costs for the seed cultivation to achieve the purpose of 1,3-propanediol continuous production. The concentration of 1,3-propanediol from first to fourth cycle was 42.89, 45.78, 44.48, 42.39 (g/L), and the corresponding volumetric productivity was 2.14, 1.91, 1.85, 2.12 (g/L · h-1 ) respectively. More importantly, a relatively complete schematic diagram of the proposed metabolic pathways was firstly mapped out based on the intracellular metabolites analysis through GC-MS. At the same time, metabolic pathway and principal components analyses were carried out to give us deep insight into metabolic state. Many metabolites occurred to response to the stress in Cycle II. Even resting body formed and lipid accumulated owing to the worsening environment in the group without activated carbon in Cycle III. Thus, it demonstrated that activated carbon provided a favorable microenvironment for Clostridium butyricum in the repeated batch fermentation process to achieve the purpose of 1,3-propanediol continuous production.


Assuntos
Carbono/metabolismo , Clostridium butyricum/crescimento & desenvolvimento , Propilenoglicóis/metabolismo , Adsorção
15.
IEEE Trans Vis Comput Graph ; 23(7): 1796-1808, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-27254869

RESUMO

We introduce an interactive user-driven method to reconstruct high-relief 3D geometry from a single photo. Particularly, we consider two novel but challenging reconstruction issues: i) common non-rigid objects whose shapes are organic rather than polyhedral/symmetric, and ii) double-sided structures, where front and back sides of some curvy object parts are revealed simultaneously on image. To address these issues, we develop a three-stage computational pipeline. First, we construct a 2.5D model from the input image by user-driven segmentation, automatic layering, and region completion, handling three common types of occlusion. Second, users can interactively mark-up slope and curvature cues on the image to guide our constrained optimization model to inflate and lift up the image layers. We provide real-time preview of the inflated geometry to allow interactive editing. Third, we stitch and optimize the inflated layers to produce a high-relief 3D model. Compared to previous work, we can generate high-relief geometry with large viewing angles, handle complex organic objects with multiple occluded regions and varying shape profiles, and reconstruct objects with double-sided structures. Lastly, we demonstrate the applicability of our method on a wide variety of input images with human, animals, flowers, etc.

16.
BMC Bioinformatics ; 16 Suppl 7: S7, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25952938

RESUMO

BACKGROUND: The reconstruction of gene regulatory network from time course microarray data can help us comprehensively understand the biological system and discover the pathogenesis of cancer and other diseases. But how to correctly and efficiently decifer the gene regulatory network from high-throughput gene expression data is a big challenge due to the relatively small amount of observations and curse of dimensionality. Computational biologists have developed many statistical inference and machine learning algorithms to analyze the microarray data. In the previous studies, the correctness of an inferred regulatory network is manually checked through comparing with public database or an existing model. RESULTS: In this work, we present a novel procedure to automatically infer and verify gene regulatory networks from time series expression data. The dynamic Bayesian network, a statistical inference algorithm, is at first implemented to infer an optimal network from time series microarray data of S. cerevisiae, then, a weighted symbolic model checker is applied to automatically verify or falsify the inferred network through checking some desired temporal logic formulas abstracted from experiments or public database. CONCLUSIONS: Our studies show that the marriage of statistical inference algorithm with model checking technique provides a more efficient way to automatically infer and verify the gene regulatory network from time series expression data than previous studies.


Assuntos
Algoritmos , Biologia Computacional/métodos , Interpretação Estatística de Dados , Perfilação da Expressão Gênica , Regulação Fúngica da Expressão Gênica/genética , Redes Reguladoras de Genes , Saccharomyces cerevisiae/genética , Genoma Fúngico , Humanos , Análise de Sequência com Séries de Oligonucleotídeos , Software , Fatores de Tempo
17.
PLoS One ; 9(8): e104578, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25119347

RESUMO

Vibrio fischeri is a typical quorum-sensing bacterium for which lux box, luxR, and luxI have been identified as the key elements involved in quorum sensing. To decode the quorum-sensing mechanism, an artificially constructed cell-cell communication system has been built. In brief, the system expresses several programmed cell-death BioBricks and quorum-sensing genes driven by the promoters lux pR and PlacO-1 in Escherichia coli cells. Their transformation and expression was confirmed by gel electrophoresis and sequencing. To evaluate its performance, viable cell numbers at various time periods were investigated. Our results showed that bacteria expressing killer proteins corresponding to ribosome binding site efficiency of 0.07, 0.3, 0.6, or 1.0 successfully sensed each other in a population-dependent manner and communicated with each other to subtly control their population density. This was also validated using a proposed simple mathematical model.


Assuntos
Aliivibrio fischeri/crescimento & desenvolvimento , Modelos Biológicos , Percepção de Quorum/fisiologia , Sítios de Ligação/genética , Morte Celular/genética , Primers do DNA/genética , Plasmídeos/genética , Reação em Cadeia da Polimerase , Densidade Demográfica , Percepção de Quorum/genética
18.
Gen Comp Endocrinol ; 204: 1-7, 2014 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-24818970

RESUMO

Muskrat is a seasonal breeder, males of which secret musk from paired perineal scented glands found beneath the skin at the ventral base of the tail for attracting female during the breeding season. The aim of this study was to investigate the seasonal changes of expression of androgen receptor (AR) in the scented gland of muskrat during the breeding and nonbreeding seasons. Histologically, glandular cells, interstitial cells and excretory tubules were identified in scented glands in both seasons, whereas epithelial cells were sparse in the nonbreeding season. AR was observed in glandular cells of scented glands during the breeding and nonbreeding seasons with stronger immunostaining during the breeding season compared to the nonbreeding season. Consistent with the immunohistochemical results, AR protein level was higher in the scented glands of the breeding season, and then decreased to a relatively low level in the nonbreeding season. The mean mRNA level of Ar was significantly higher in the breeding season than in the nonbreeding season. In addition, plasma gonadotropins and testosterone concentrations were remarkably higher in the breeding season than those in the nonbreeding season. These results suggested that muskrat scented gland was the direct target organ of androgen, and stronger expression of AR in scented glands during the breeding season suggested that androgens may directly influence scented glandular function of the muskrats and also courtship behavior as we inferred.


Assuntos
Androgênios/sangue , Arvicolinae/fisiologia , Receptores Androgênicos/metabolismo , Glândulas Odoríferas/metabolismo , Estações do Ano , Testosterona/sangue , Animais , Cruzamento , Feminino , Masculino , Períneo/fisiologia
20.
J Ovarian Res ; 7: 3, 2014 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-24405743

RESUMO

The aim of this study was to investigate the presence of nerve growth factor (NGF) and its receptors tyrosine kinase A (TrkA) and p75 in the ovaries of the wild ground squirrels during the breeding and nonbreeding seasons. In the breeding period, NGF, TrkA and p75 were immunolocalized in granulosa cells, thecal cells, interstitial cells and luteal cells whereas in the nonbreeding period, both of them were detected only in granulosa cells, thecal cells and interstitial cells. Stronger immunostaining of NGF, TrkA and p75 were observed in granulosa cells, thecal cells and interstitial cells in the breeding season compared to the nonbreeding season. Corresponding for the immunohistochemical results, immunoreactivities of NGF and its two receptors were greater in the ovaries of the breeding season then decreased to a relatively low level in the nonbreeding season. The mean mRNA levels of NGF, TrkA and p75 were significantly higher in the breeding season than in the nonbreeding season. In addition, plasma gonadotropins, estradiol-17ß and progesterone concentrations were significantly higher in the breeding season than in the nonbreeding season, suggesting that the expression patterns of NGF, and TrkA and p75 were correlated with changes in plasma gonadotropins, estradiol-17ß and progesterone concentrations. These results indicated that NGF and its receptors, TrkA and p75 may be involved in the regulation of seasonal changes in the ovarian functions of the wild ground squirrel.


Assuntos
Fator de Crescimento Neural/metabolismo , Ovário/enzimologia , Receptor de Fator de Crescimento Neural/metabolismo , Receptor trkA/metabolismo , Sciuridae/metabolismo , Estações do Ano , Animais , Biomarcadores/sangue , Estradiol/sangue , Feminino , Regulação Enzimológica da Expressão Gênica , Gonadotropinas/sangue , Fator de Crescimento Neural/genética , Ovário/citologia , Progesterona/sangue , RNA Mensageiro/metabolismo , Receptor de Fator de Crescimento Neural/genética , Receptor trkA/genética , Reprodução , Sciuridae/sangue , Sciuridae/genética , Fatores de Tempo
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