Characterization of proteinase A excretion from Saccharomyces cerevisiae in high sugar stress conditions

Dong, Liang,Li, Feng,Piao, Yongzhe,Sun, Dong,Zhao, Rui,Li, Cheng,Cong, Lina,Zhao, Changxin The Korean Society for Applied Biological Chemistr 2015 Applied Biological Chemistry (Appl Biol Chem) Vol.58 No.2

High sugar concentration culturing was commonly used in modern fermentation industry. However, it leads to the reduction of the foam stability in beer brewing due to the excess secretion of proteinase A. To better understand the characterization of proteinase A excretion from Saccharomyces cerevisiae in high sugar stress conditions, the cultures were grown by using YNB medium with a high concentration of glucose. Pro-PrA isolated from the medium was purified by gel exclusion chromatography, and the PrA activity was detected using fluorescent substrate analysis. The relative molecular weight of the purified PrA and pro-PrA was estimated at 42 and 54 kDa, respectively, by SDS-PAGE. It indicated that the metabolic behavior of PrA in the high glucose culturing was quite different from the normal conditions, and glucose concentration may have a big influence on its secreted process. Further study showed that PrA was released at the logarithmic growth phase of the culturing, and the amount of PrA was 11 times higher compared with the normal culturing. PrA was considered to be activated by itself under acidic conditions. And it was also confirmed in this work that the step-wise pathway for the autoactivation known as a pseudo-PrA has a major contribution to the autoactivation process of PrA zymogen outside the cell.

Characterization of proteinase A excretion from Saccharomyces cerevisiae in high sugar stress conditions

Liang Dong,Feng Li,Yongzhe Piao,Dong Sun,Rui Zhao,Cheng Li,Lina Cong,Changxin Zhao 한국응용생명화학회 2015 Applied Biological Chemistry (Appl Biol Chem) Vol.58 No.2

High sugar concentration culturing was commonly used in modern fermentation industry. However, it leads to the reduction of the foam stability in beer brewing due to the excess secretion of proteinase A. To better understand the characterization of proteinase A excretion from Saccharomyces cerevisiae in high sugar stress conditions, the cultures were grown by using YNB medium with a high concentration of glucose. Pro-PrA isolated from the medium was purified by gel exclusion chromatography, and the PrA activity was detected using fluorescent substrate analysis. The relative molecular weight of the purified PrA and pro-PrA was estimated at 42 and 54 kDa, respectively, by SDS-PAGE. It indicated that the metabolic behavior of PrA in the high glucose culturing was quite different from the normal conditions, and glucose concentration may have a big influence on its secreted process. Further study showed that PrA was released at the logarithmic growth phase of the culturing, and the amount of PrA was 11 times higher compared with the normal culturing. PrA was considered to be activated by itself under acidic conditions. And it was also confirmed in this work that the step-wise pathway for the autoactivation known as a pseudo-PrA has a major contribution to the autoactivation process of PrA zymogen outside the cell.

Pretension design of a flexible support cable net structure with high node position precision

Hangjia Dong,Tuanjie Li,Cong-Cong Chen 대한기계학회 2023 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.37 No.6

A prestressed cable net structure is applied to shape and support the reflective surface of mesh antennas. The radiation pattern of an antenna highly depends on the positions of the cable net nodes. The pretension force and node positions of the cable net structure are strongly coupled. The deformation of the flexible support frame changes the positions of the cable net nodes, causing the radiation pattern to deteriorate. To achieve high node position precision, this study proposes the pretension design method of a cable net structure with flexible supports. To improve calculation efficiency, finite element method and force density method are combined to calculate structural deformation directly and accurately. Furthermore, a pretension optimization model is established by considering the rigid body displacements of the nodes. This model is solved iteratively. Numerical results show that the proposed pretension design method can achieve high design accuracy for a flexible support cable net structure and significantly improve the mechanical properties of a support frame.

Serum Carbohydrate Antigen 19-9 as an Indicator of Liver Metastasis in Colorectal Carcinoma Cases

Dong, Hang,Tang, Jie,Li, Long-Hao,Ge, Jun,Chen, Xin,Ding, Jing,Men, Hai-Tao,Luo, Wu-Xia,Du, Yang,Li, Cong,Zhao, Feng,Chen, Ye,Cheng, Ke,Liu, Ji-Yan Asian Pacific Journal of Cancer Prevention 2013 Asian Pacific journal of cancer prevention Vol.14 No.2

Purpose: The liver is the organ to which colorectal carcinomas (CRCs) most commonly metastasize, and surgical resection has been established as the most effective and potentially curative treatment for CRC with liver metastasis (LM). Therefore, surveillance of LM is vital for improvement of prognosis of CRC patients. In this study, we aimed to explore the potential value of carbohydrate antigen 19-9 (CA 19-9), carcinoembryonic antigen (CEA), and marker enzymes in indicating LM with CRC. Methods: Three groups of eligible patients with metastatic cancers were retrospectively included: CRC patients with LM (CRC-LM) or without LM (CRC-NLM), and non-CRC patients with LM (NCRC-LM). All metastatic lesions were identified by CT or MRI. Data on characteristics of the patients, the primary site, the locations of metastasis, CA 19-9, CEA, and biochemical parameters were collected for analysis. Results: A total of 493 patients were retrospectively included. More alcohol consumption was found in CRC-LM than CRC-NLM. Some biochemical enzymes were found to be significantly higher in groups with LM than without (CRC-LM or NCRC-LM v.s CRC-NLM). Both CEA and CA 19-9 were much higher in CRC-LM than CRC-NLM or NCRC-LM. For CRC patients, CA 19-9, ${\gamma}$-glutamyl transpeptidase, CEA and alcohol consumption were identified as independent factors associated with LM. Conclusion: Our analysis suggested the CA 19-9 might be a potential valuable indicator for LM of CRC in the clinic.

A New Cache Replacement Policy for Improving Last Level Cache Performance

Cong Thuan Do(두콩튜안),Dong Oh Son(손동오),Jong Myon Kim(김종면),Cheol Hong Kim(김철홍) 한국정보과학회 2014 정보과학회논문지 Vol.41 No.11

캐쉬 교체 기법은 캐쉬 미스를 감소시키기 위해서 개발되었다. 마이크로프로세서와 주기억장치의 속도 차이를 해결하기 위해서는 캐쉬 교체 기법의 성능이 중요하다. 일반적인 캐쉬 교체 기법으로는 LRU 기법이 있으며 대부분의 마이크로프로세서에서 캐쉬 교체 기법으로 LRU 기법을 사용한다. 그러나, 최근의 연구에 따르면 LRU 기법과 최적 교체(OPT) 기법 간의 성능 차이는 매우 크다. LRU 기법의 성능은 많은 연구를 통해서 검증되었지만, 캐쉬 사상방식이 높아질수록 LRU 기법과 OPT 기법의 성능 차이는 증가한다. 본 논문에서는 기존의 LRU 기법을 활용하여 캐쉬 성능을 향상시키는 캐쉬 교체 기법을 제안하였다. 제안된 캐쉬 교체 기법은 캐쉬 블록의 접근율에 따라 교체 대상을 선정하여 캐쉬 블록을 교체시킨다. 제안된 캐쉬 교체 기법은 512KB L2 캐쉬에서 기존의 LRU 기법과 비교하여 평균 15%의 미스율을 감소시켰고, 프로세서 성능은 4.7% 향상됨을 알 수 있다. Cache replacement algorithms have been developed in order to reduce miss counts. In modern processors, the performance gap between the processor and main memory has been increasing, creating a more important role for cache replacement policies. The Least Recently Used (LRU) policy is one of the most common policies used in modern processors. However, recent research has shown that the performance gap between the LRU and the theoretical optimal replacement algorithm (OPT) is large. Although LRU replacement has been proven to be adequate over and over again, the OPT/LRU performance gap is continuously widening as the cache associativity becomes large. In this study, we observed that there is a potential chance to improve cache performance based on existing LRU mechanisms. We propose a method that enhances the performance of the LRU replacement algorithm based on the access proportion among the lines in a cache set during a period of two successive replacement actions that make the final replacement action. Our experimental results reveals that the proposed method reduced the average miss rate of the baseline 512KB L2 cache by 15 percent when compared to conventional LRU. In addition, the performance of the processor that applied our proposed cache replacement policy improved by 4.7 percent over LRU, on average.

The Stent-Assisted Coil-Jailing Technique Facilitates Efficient Embolization of Tiny Cerebral Aneurysms

Cong-Hui Li,Xian-Hui Su,Bo Zhang,Yong-Feng Han,Er-Wei Zhang,Lei Yang,Dong-Liang Zhang,Song-Tao Yang,Zhen-Quan Yan,Bu-Lang Gao 대한영상의학회 2014 Korean Journal of Radiology Vol.15 No.6

Objective: Tiny cerebral aneurysms are difficult to embolize because the aneurysm’s sac is too small for a single small coil, and coils within the aneurysm may escape from the confinement of a stent. This study was performed to introduce the stent-assisted coil-jailing technique and to investigate its effect on the coil embolization of tiny intracranial aneurysms. Materials and Methods: Sixteen patients with tiny intracranial aneurysms treated with the stent-assisted coil-jailing technique between January 2011 and December 2013 were retrospectively reviewed and followed-up. Results: All aneurysms were successfully treated with the coil-jailing technique, and at the end of embolization, complete occlusion of the aneurysm was achieved in 9 cases (56.3%), incomplete occlusion in 6 (37.5%), and partial occlusion in 1 (6.3%). Intraprocedural complications included acute thrombosis in one case (6.3%) and re-rupture in another (6.3%). Both complications were managed appropriately with no sequela. Follow-up was performed in all patients for 3–24 months (mean, 7.7 months) after embolization. Complete occlusion was sustained in the 9 aneurysms with initial complete occlusion, progressive thrombosis to complete occlusion occurred in the 6 aneurysms with initial near-complete occlusion, and one aneurysm resulted in progressive thrombosis to complete occlusion after initial partial occlusion. No migration of stents or coils occurred at follow-up as compared with their positions immediately after embolization. At follow-up, all patients had recovered with no sequela. Conclusion: The stent-assisted coil-jailing technique can be an efficient approach for tiny intracranial aneurysms, even though no definite conclusion regarding its safety can be drawn from the current data.

Visual Attention Servo Control for Task-specific Robotic Applications

Dong Liu,Ming Cong,Yu Du,Yunfei Zhang,Clarence W. de Silva 제어·로봇·시스템학회 2013 International Journal of Control, Automation, and Vol.11 No.6

This paper proposes a visual attention servo control (VASC) method which uses the Gaussian mixture model (GMM) for task-specific applications of mobile robots. In particular, low dimensional bias feature template is obtained using GMM to get an efficient attention process. An image-based visual servo (IBVS) controller is used to search for a desired object in a scene through an attention system which forms a task-specific state representation of the environment. First, task definition and object representation in semantic memory (SM) are proposed, and bias feature template is obtained using GMM deduction for features from high dimension to low dimension. Second, the features intensity, color, size and orientation are extracted to build the feature set. Mean shift method is used to segment the visual scene into discrete proto-objects. Given a task-specific object, top-down bias attention is evaluated to generate the saliency map by combining with the bottom-up saliency-based attention. Third, a visual attention servo controller is developed to integrate the IBVS controller and the attention system for robotic cognitive control. A rule-based arbitrator is proposed to switch between the episodic memory (EM)-based controller and the IBVS controller depending on whether the robot obtains the desired attention point on the image. Finally, the proposed method is evaluated on task-specific object detection under different conditions and visual attention servo tasks. The obtained results validate the applicability and usefulness of the developed method for robotics.

Phloretin Ameliorates Succinate-Induced Liver Fibrosis by Regulating Hepatic Stellate Cells

Cong Thuc Le,Giang Nguyen,박소영,Hanh Nguyen Dong,조윤경,이재호,임승순,최대호,조은희 대한내분비학회 2023 Endocrinology and metabolism Vol.38 No.4

Background: Hepatic stellate cells (HSCs) are the major cells which play a pivotal role in liver fibrosis. During injury, extracellular stimulators can induce HSCs transdifferentiated into active form. Phloretin showed its ability to protect the liver from injury, so in this research we would like to investigate the effect of phloretin on succinate-induced HSCs activation in vitro and liver fibrosis in vivo study. Methods: In in vitro, succinate was used to induce HSCs activation, and then the effect of phloretin on activated HSCs was examined. In in vivo, succinate was used to generated liver fibrosis in mouse and phloretin co-treated to check its protection on the liver. Results: Phloretin can reduce the increase of fibrogenic markers and inhibits the proliferation, migration, and contraction caused by succinate in in vitro experiments. Moreover, an upregulation of proteins associated with aerobic glycolysis occurred during the activation of HSCs, which was attenuated by phloretin treatment. In in vivo experiments, intraperitoneal injection of phloretin decreased expression of fibrotic and glycolytic markers in the livers of mice with sodium succinate diet-induced liver fibrosis. These results suggest that aerobic glycolysis plays critical role in activation of HSCs and succinate can induce liver fibrosis in mice, whereas phloretin has therapeutic potential for treating hepatic fibrosis. Conclusion: Intraperitoneal injection of phloretin attenuated succinate-induced hepatic fibrosis and alleviates the succinate-induced HSCs activation.

Asiatic Acid Protects Dopaminergic Neurons from Neuroinflammation by Suppressing Mitochondrial ROS Production

( Dong Chen ),( Xiao-ya Zhang ),( Jing Sun ),( Qi-jie Cong ),( Wei-xiong Chen ),( Hafiz Muhammad Ahsan ),( Jing Gao ),( Jin-jun Qian ) 한국응용약물학회 2019 Biomolecules & Therapeutics(구 응용약물학회지) Vol.27 No.5

This study sought to evaluate the effects of Asiatic acid in LPS-induced BV2 microglia cells and 1-methyl-4-phenyl-pyridine (MPP+)-induced SH-SY5Y cells, to investigate the potential anti-inflammatory mechanisms of Asiatic acid in Parkinson’s disease (PD). SH-SY5Y cells were induced using MPP+ to establish as an in vitro model of PD, so that the effects of Asiatic acid on dopaminergic neurons could be examined. The NLRP3 inflammasome was activated in BV2 microglia cells to explore potential mechanisms for the neuroprotective effects of Asiatic acid. We showed that Asiatic acid reduced intracellular production of mitochondrial reactive oxygen species and altered the mitochondrial membrane potential to regulate mitochondrial dysfunction, and suppressed the NLRP3 inflammasome in microglia cells. We additionally found that treatment with Asiatic acid directly improved SH-SY5Y cell viability and mitochondrial dysfunction induced by MPP+. These data demonstrate that Asiatic acid both inhibits the activation of the NLRP3 inflammasome by downregulating mitochondrial reactive oxygen species directly to protect dopaminergic neurons from, and improves mitochondrial dysfunction in SH-SY5Y cells, which were established as a model of Parkinson’s disease. Our finding reveals that Asiatic acid protects dopaminergic neurons from neuroinflammation by suppressing NLRP3 inflammasome activation in microglia cells as well as protecting dopaminergic neurons directly. This suggests a promising clinical use of Asiatic acid for PD therapy.

The Relationship Between Business Resources, Outside Cooperation, Dynamic Capability, and Performance of Startup Enterprises

Dong Van VU1,Tai Van PHAM2,Ghi Nha TRAN3,Anh Phuong Thi NGUYEN4,Cong Van NGUYEN5 한국유통과학회 2021 The Journal of Asian Finance, Economics and Busine Vol.8 No.6

This study seeks to examine the relationship between business resources (through VRIN: Valuable - valuable, Rare - scarce; Inimitable - difficult to adapt, Irreplaceable - hard to replace), dynamic capability, external cooperation, and efficiency of startups operating in the seafood export sector. Research data was collected randomly and conveniently from 250 enterprises in Ba Ria-Vung Tau province, Vietnam, from October 2020 to December 2020. After excluding those ineligible, the remaining 204 enterprises meet the research conditions. With the support of SPSS-AMOS 22 dedicated software, using the 5-step Likert scale and Structural Equation Modeling (SEM), the study conducted analysis steps such as verifying convergence, discriminant value, unidirectional and scale reliability when giving the components correlated freely in the critical model by Confirmatory Factor Analysis (CFA) analysis. Results of the study have shown that the enterprise resource factor - VRIN has a positive impact on dynamic capability, and outside cooperation. However, in contrast to previous studies, we found that the relationship between enterprise resources - VRIN and performance as well as the relationship between dynamics capacity and performance is not clear. This shows that seafood exporters need to promote, exploit and effectively use this precious resource to improve business efficiency.