Nutrition and bioprocess development for efficient biosynthesis of an antitumor compound from marine-derived fungus

An integrated nutrition and bioprocess strategy was developed for improving the biosynthesis of an antitumor compound, 1403C, by a marine-derived fungus, Halorosellinia sp. (no. 1403). First, statistical design strategies were synthetically applied to optimize the nutritional composition. The resulting 1403C production reached 2.07 g/l, which was 143.5 % higher than the original production. However, it only produced 0.44 g/l of 1403C in 5-l bioreactor fermentation. Thus, the operating parameters including culture pH, dissolved oxygen, agitation speed, impeller type and inoculum level were considered to improve the fermentation process, and an effective control strategy for 1403C production by Halorosellinia sp. submerged in a 5-l bioreactor was established. When inoculating 0.22 g/l dry biomass, controlling dissolved oxygen not lower than 30 % during the growth phase but ranging between 30 and 40 % during the stationary phase, using a double-layer six-flat-blade Rushton disc turbine agitated at 400 rpm, keeping short-term low pH and rapid-rising pH with glucose starvation, the highest 1403C production was finally obtained at 1.32 g/l, which was promoted by 200 % compared to before optimization. Fermentation scale-up was finally performed in a 500-l bioreactor, and 1403C production of 1.09 g/l was obtained.     

Responses of macrophages against Salmonella infection compared with phagocytosis

To explore the responses of host cell after infection with live Salmonella compared with phagocytosis to dead bacteria, the responses of mouse macrophage after infection with Salmonella enteritidis C50041 and the fixed C50041 (C50041-d) were analyzed. Results indicated that the cytotoxicity induced by C50041 was stronger than C50041-d. Similar changing trends of mitochondrial membrane potential, intracellular concentration of calcium ions, reactive oxygen species and nitric oxide were found between C50041 and C50041-d infection. But the cell responses against C50041 were earlier and stronger than C50041-d. LC3 expression of macrophage induced by C50041 was lower than C50041-d. C50041 significantly inhibited the production of tumor necrosis factor and interleukin (IL)-6. Whereas intracellular caspase-1 activation and IL-1β release induced by C50041 were stronger than C50041-d, caspase-1 activation and IL-1β release are the innate defense responses of macrophage. Therefore, it will be beneficial to explore the use of this pathway in the control of Salmonella infection.     

Altered miRNA Expression is Associated with Differentiation, Invasion, and Metastasis of Esophageal Squamous Cell Carcinoma (ESCC) in Patients from Huaian, China

Esophageal squamous cell carcinoma (ESCC) is the leading malignancy in Huaian, China. Recently, emerging studies have suggested that an aberrant microRNA (miRNA) expression signature exists in ESCC. However, there is discordant information available on specific miRNA expression in patients from different regions. In this study, we identified 12 miRNAs that are differentially expressed in patients with ESCC from Huaian, China. Among these miRNAs that displayed unique miRNA expression signatures, miR-1, miR-29c, miR-100, miR-133a, miR-133b, miR-143, miR-145, and miR-195 were downregulated, and miR-7, miR-21, miR-223, and miR-1246 were upregulated in cancerous tissue compared with the adjacent normal tissue. Bioinformatics analyses identified the major biological processes and signaling pathways that are targeted by these differentially expressed miRNAs. Accordingly, miR-29c, miR-100, miR-133a, and miR-133b were found to be involved in invasion and metastasis of ESCC, and miR-7 and miR-21 were found to be related to the differentiation of ESCC. Thus, our data present new evidence for the important roles of miRNAs in ESCC.     

基于InVEST模型的金沙江流域干热河谷区水源涵养功能评估

以金沙江流域干热河谷区1990年、2000年、2010年和2019年4期Landsat遥感影像为基础数据,通过目视解译和最大似然相结合的方法进行土地利用类型分类,定量分析金沙江流域干热河谷区土地利用类型的时间变化与空间转移过程;采用InVEST模型,结合气象、土壤和地形等数据评估了1990-2019年金沙江流域干热河谷区及不同土地利用类型的产水功能和水源涵养功能。结果表明：1）1990-2019年金沙江流域干热河谷区土地利用类型以草地、乔木林地和耕地为主;近30年来,灌木林地、建设用地、交通运输用地和水域的面积不断增加,建设用地面积增幅最大;草地、乔木林地、耕地和裸地面积均减少。2）1990-2019年,建设用地、灌木林地、交通运输用地和水域面积的增加来源于草地、耕地和乔木林地。3）金沙江流域干热河谷区多年平均产水量为26.09×10⁸ m³,水源涵养量为7.26×10⁸ m³,产水量的变化与分布直接影响着区域的水源含养量;平均水源涵养能力68.74 mm,呈现上升-下降-上升的波动变化趋势。4）1990-2019年不同土地利用类型的水源涵养量变化明显,不同地类平均水源涵养量的大小依次为耕地 > 草地 > 建设用地 > 乔木林地 > 交通运输用地 > 灌木林地 > 裸地 > 水域。     

Development and characterization of 14 novel microsatellite markers for an invasive goby (Tridentiger bifasciatus) in water transfer system

Genetic patterns observed among populations by neutral molecular markers is a major method used to reconstruct the invasion history of invasive species. The Shimofuri goby (Tridentiger bifasciatus) has invaded several lakes along the East Route of the South-to-North Water Transfer Project, China (ENST). However, neutral molecular markers for this goby are not currently available. In this study, fourteen novel polymorphic microsatellite loci were developed through next generation sequencing technology. These markers were also tested in an invasive population (Nansi Lake, a storage lake of ENST) consisting of 54 individuals. The average number of alleles per locus was 7.6 and ranged from 4 to 13. The average H_o was 0.587 and ranged from 0.404 to 0.852, and the average H_e was 0.733 and ranged from 0.564 to 0.851. The average PIC per locus was 0.689 and ranged from 0.521 to 0.824. Four markers (TB4, TB65, TB66 and TB26) were found to deviate from HWE after correction following the False Discovery Rate method. Null alleles were found in four loci (TB11, TB65, TB66 and TB26). These highly polymorphic microsatellite markers are useful for further study to reconstruct invasion history of Shimofuri goby.