Transient virus-induced gene silencing of MaBAM9b efficiently suppressed starch degradation during postharvest banana fruit ripening

Liu Mengting,Li Meng,Wang Yudi,Wang Jingyi,Miao Hongxia,Wang Zhuo,Xu Biyu,Li Xinguo,Jin Zhiqiang,Liu Juhua 한국식물생명공학회 2021 Plant biotechnology reports Vol.15 No.4

The genetic basis of metabolic pathways that operate during fruit ripening needs to be understood before the nutritional value of the banana can be improved. The banana is a typical starch conversion fruit, and β-amylase is a key enzyme that may play an important role in starch degradation during the ripening process. Musa acuminata β-amylase 9b (MaBAM9b) is closely related to starch degradation. However, its exact function in starch degradation has not been demonstrated in banana. Stable genetic transformation to identify gene function is a time- and energy-consuming process. Thus, an efficient and rapid method is needed for functional identification. Virus-induced gene silencing (VIGS) is a reverse-genetics method based on RNA-mediated antiviral plant defense that has been used to rapidly identify gene functions in plants. The aim of this study was to optimize a transient VIGS system and functionally elucidate MaBAM9b in postharvest banana fruit. Using 2- to 4-mm-thick fruit slices, vacuum infiltration of suspensions of Agrobacterium strains carrying TRV1 and TRV2-MaBAM9b, 0.5% iodine-potassium-iodide (I2-KI) staining for 150 s, and 1:3 TRV1:TRV2-MaBAM9b cultivation at 30 mmHg for 30 s achieved an optical density (OD) of 0.8 at 600 nm; after being incubated on Murashige and Skoog (MS) media for 5 days (d), starch degradation was efficiently suppressed during postharvest banana fruit ripening, as determined by I2-KI staining, total starch content, β-amylase activity, soluble sugar content, and endogenous MaBAM9b expression. The system described here is particularly useful for studying genes and networks involved in starch conversion in fruits, which alone would not produce a visual phenotype. This system will provide a platform for functional genomics and fruit quality improvement in banana.

Research on the Mechanical Properties of Some New Aluminum Alloy Composite Structures in Construction Engineering

Mengting Fan,Xuan Wang 한국재료학회 2024 한국재료학회지 Vol.34 No.2

The lightweight and high strength characteristics of aluminum alloy materials make them have promising prospects in the field of construction engineering. This paper primarily focuses on aluminum alloy materials. Aluminum alloy was combined with concrete, wood and carbon fiber reinforced plastic (CFRP) cloth to create a composite column. The axial compression test was then conducted to understand the mechanical properties of different composite structures. It was found that the pure aluminum tube exhibited poor performance in the axial compression test, with an ultimate load of only 302.56 kN. However, the performance of the various composite columns showed varying degrees of improvement. With the increase of the load, the displacement and strain of each specimen rapidly increased, and after reaching the ultimate load, both load and strain gradually decreased. In comparison, the aluminum alloy-concrete composite column performed better than the aluminum alloy-wood composite column, while the aluminum alloy-wood-CFRP cloth composite column demonstrated superior performance. These results highlight excellent performance potential for aluminum alloy-wood-CFRP composite columns in practical applications.

Distributed Multimedia Scheduling in the Cloud

Zheng, Mengting,Wang, Wei Korea Multimedia Society 2015 The journal of multimedia information system Vol.2 No.1

Multimedia services in the cloud have become a popular trend in the big data environment. However, how to efficiently schedule a large number of multimedia services in the cloud is still an open and challengeable problem. Current cloud-based scheduling algorithms exist the following problems: 1) the content of the multimedia is ignored, and 2) the cloud platform is a known parameter, which makes current solutions are difficult to utilize practically. To resolve the above issues completely, in this work, we propose a novel distributed multimedia scheduling to satisfy the objectives: 1) Develop a general cloud-based multimedia scheduling model which is able to apply to different multimedia applications and service platforms; 2) Design a distributed scheduling algorithm in which each user makes a decision based on its local information without knowing the others' information; 3) The computational complexity of the proposed scheduling algorithm is low and it is asymptotically optimal in any case. Numerous simulations have demonstrated that the proposed scheduling can work well in all the cloud service environments.

Emotional Children Air Purifier Product Design

Xia Mengting,Wang Zhenxing 한국디자인학회 2023 한국디자인학회 국제초대전도록 Vol.2023 No.10

The Clinical Characteristic and Management of Patients with Nocardiosis in a Tertiary Hospital in China

Liu Peilin,Wang Zhiqian,Jian Zijuan,Liu Xuan,Li Yanming,Yan Qun,Zhong Baiyun,Liao Mengting,Liang Xianghui,Liu Wenen 한국미생물·생명공학회 2023 Journal of microbiology and biotechnology Vol.33 No.5

Nocardiosis is an uncommon opportunistic bacterial infection which becomes a significant health problem due to its increasing incidence and high mortality rate. However, many nocardiosis patients are underdiagnosed by physicians. To summarize the clinical characteristics and management of nocardiosis would help with better diagnosis and prognosis of nocardiosis. This retrospective study was conducted based on the medical records of nocardiosis patients between January 2015 and December 2021 in a tertiary hospital in China. Overall, 44 nocardiosis patients with 54 specimens were included. The patients consisted of 26 males and 18 females with a mean age of 50.4 ± 13.2 years. Among 44 patients, 26 (59.1%) were previously given immunosuppressive therapy. Connective tissue diseases (CTDs) were the most common underlying disease (16/44). The most frequent infection sites were the lungs (17/44) and skin or soft tissues (8/44). Common symptoms included cough (23/44), expectoration (18/44), fever (15/44), and subcutaneous abscesses (15/44). Forty-five out of 54 specimens (83.3%) required over 48 hours of culture time for nocardiosis detection. Thirty-six patients were cured or improved, 5 patients were discharged from the hospital due to poor prognosis, and 1 patient died. The average diagnosis time of poor prognosis cases was 19.7 days, which was significantly longer than those of improved or cured patients (7.3 days). Immunosuppressed patients comprise a large part of nocardiosis cases, which is worth attention in clinical practice. Early diagnosis, specifically through prolonged cultivation time of specimen, could help achieve better prognosis of nocardiosis patients.

Sequential anti-inflammatory and osteogenic effects of a dual drug delivery scaffold loaded with parthenolide and naringin in periodontitis

Rui Chen,Mengting Wang,Qiaoling Qi,Yanli Tang,Zhenzhao Guo,Shuai Wu,Qiyan Li 대한치주과학회 2023 Journal of Periodontal & Implant Science Vol.53 No.1

Purpose: Our pilot study showed that a 3-dimensional dual drug delivery scaffold (DDDS) loaded with Chinese herbs significantly increased the regenerated bone volume fraction. This study aimed to confirm the synergistic anti-inflammatory and osteogenic preclinical effects of this system. Methods: The targets and pathways of parthenolide and naringin were predicted. Three cell models were used to assess the anti-inflammatory effects of parthenolide and the osteogenic effects of naringin. First, the distance between the cementoenamel junction and alveolar bone crest (CEJ-ABC) and the bone mineral density (BMD) of surgical defects were measured in a rat model of periodontitis with periodontal fenestration defects. Additionally, the mRNA expression levels of matrix metallopeptidase 9 (MMP9) and alkaline phosphatase (ALP) were measured. Furthermore, the number of inflammatory cells and osteoclasts, as well as the protein expression levels of tumor necrosis factor-alpha (TNF-α) and levels of ALP were determined. Results: Target prediction suggested prostaglandin peroxidase synthase (PTGS2) as a potential target of parthenolide, while cytochrome P450 family 19 subfamily A1 (CYP19A1) and taste 2 receptor member 31 (TAS2R31) were potential targets of naringin. Parthenolide mainly targeted inflammation-related pathways, while naringin participated in steroid hormone synthesis and taste transduction. In vitro experiments revealed significant antiinflammatory effects of parthenolide on RAW264.7 cells, and significant osteogenic effects of naringin on bone marrow mesenchymal stem cells and MC3T3-E1 cells. DDDS loaded with parthenolide and naringin decreased the CEJ-ABC distance and increased BMD and ALP levels in a time-dependent manner. Inflammation was significantly alleviated after 14 days of DDDS treatment. Additionally, after 56 days, the DDDS group exhibited the highest BMD and ALP levels. Conclusions: DDDS loaded with parthenolide and naringin in a rat model achieved significant synergistic anti-inflammatory and osteogenic effects, providing powerful preclinical evidence.

Using tyrosinase as a tri-modality reporter gene to monitor transplanted stem cells in acute myocardial infarction

Mei Liu,Yichun Wang,Mengting Li,Hongyan Feng,Qingyao Liu,Chunxia Qin,Yongxue Zhang,Xiaoli Lan 생화학분자생물학회 2018 Experimental and molecular medicine Vol.50 No.-

The study aimed to investigate the feasibility of noninvasive monitoring of bone marrow mesenchymal stem cells (MSCs) transduced with the tyrosinase reporter gene for acute myocardial infarction (AMI) with photoacoustic imaging (PAI), magnetic resonance imaging (MRI), and positron emission tomography (PET) in vitro and in vivo. MSCs were transduced with a lentivirus carrying a tyrosinase reporter gene. After transduction, the rate of 18F-5-fluoro-N-(2- [diethylamino]ethyl)picolinamide (18F-5-FPN) uptake was measured. PAI and MRI of stable cell lines expressing tyrosinase (TYR-MSCs) were performed in vitro. An AMI model was induced and verified. TYR-MSCs and MSCs were injected into the margins of the infarcted areas, and PAI, MRI, and PET images were acquired 1, 7, 14, 21, and 28 days after cell injection. Sham-operated models without injection were used as the control group. TYR-MSCs showed noticeably higher uptake of 18F-5-FPN and stronger signals in T1-weighted MRI and PAI than non-transduced MSCs. In vivo studies revealed prominent signals in the injected area of the infarcted myocardium on PAI/MRI/PET images, whereas no signal could be seen in rats injected with non-transduced MSCs or sham-operated rats. The uptake values of 18F-5-FPN in vivo showed a slight decrease over 28 days, whereas MRI and PAI signal intensity decreased dramatically. MSCs stably transduced with the tyrosinase reporter gene could be monitored in vivo in myocardial infarction models by PET, MRI, and PAI, providing a feasible and reliable method for checking the viability, location, and dwell time of transplanted stem cells.