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1.
Biotechnol Bioeng ; 117(11): 3345-3355, 2020 11.
Artículo en Inglés | MEDLINE | ID: mdl-32678455

RESUMEN

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.


Asunto(s)
Técnicas de Cultivo de Célula/métodos , Clostridium butyricum/metabolismo , Fermentación/fisiología , Redes Neurales de la Computación , Glicoles de Propileno , Reactores Biológicos/microbiología , Medios de Cultivo/análisis , Medios de Cultivo/química , Medios de Cultivo/metabolismo , Glicerol/análisis , Glicerol/metabolismo , Cinética , Glicoles de Propileno/análisis , Glicoles de Propileno/metabolismo
2.
Biotechnol Bioeng ; 115(3): 684-693, 2018 03.
Artículo en Inglés | MEDLINE | ID: mdl-29105732

RESUMEN

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.


Asunto(s)
Carbono/metabolismo , Clostridium butyricum/crecimiento & desarrollo , Glicoles de Propileno/metabolismo , Adsorción
3.
Appl Biochem Biotechnol ; 191(2): 893-903, 2020 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-31912425

RESUMEN

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.


Asunto(s)
Proteínas Bacterianas/genética , Regulación Bacteriana de la Expresión Génica , Percepción de Quorum/genética , Genes Bacterianos/genética , Metaloendopeptidasas/genética , Regiones Promotoras Genéticas , Proteínas Represoras , Transactivadores
4.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 28(4): 1183-1188, 2020 Aug.
Artículo en Zh | MEDLINE | ID: mdl-32798396

RESUMEN

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.


Asunto(s)
Trasplante de Células Madre Hematopoyéticas , Leucemia Mieloide Aguda , Adulto , Humanos , Recurrencia Local de Neoplasia , Pronóstico , Resultado del Tratamiento , Tirosina Quinasa 3 Similar a fms
5.
IEEE Trans Vis Comput Graph ; 23(7): 1796-1808, 2017 07.
Artículo en Inglés | MEDLINE | ID: mdl-27254869

RESUMEN

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.

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