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[ Objective ] The NAC transcription factor family is a class of transcription factors that is widely studied in plants. It plays an important role in regulating plant growth and development and responding to abiotic stress. Maize is one of the three major food crops , which faces various adverse stresses in growth and development. Salt stress is one of the main environmental factors limiting crop growth and produc- tion. Therefore , it is of great significance to identify maize salt resistance genes and analyze their salt re- sistance mechanism for breeding stress-resistant maize varieties. [ Methods ] This study cloned the maize transcription factor ZmNAC59 and analyzed its conserved domain and phylogenetic relationship using bioinformatics methods. The expression pattern of the gene in leaves under NaCl and MeJA treatments was analyzed using the quantitative real-time PCR method. The stable transgenic system was used to het- erologously express the gene in Arabidopsis thaliana for phenotype observation. At the same time , virus- induced silencing technology was used to silence the gene in maize , followed by phenotype observation un- der salt stress and enzyme activity detection. [ Results ] The qRT-PCR results showed that ZmNAC59 was up-regulated by NaCl and MeJA treatments. After virus-induced silencing of ZmNAC59 , the silenced strains were more sensitive to salt stress and accumulated more ROS. After over expression of ZmNAC59 in A . thaliana , the over expression lines had higher survival rate , less accumulation of ROS , and lower Na + / K + ratios under salt stress , indicating that ZmNAC59 , as a positive regulator of salt stress , can im- prove plant salt resistance by regulating ion homeostasis. qRT-PCR results showed that Na + and K + transport related genes were significantly up-regulated in A . thaliana overexpression lines. After transient expression of ZmNAC59 in maize protoplasts , the expression of ZmSOS1 , ZmNHX1 , and ZmNHX7 were significantly up-regulated after salt treatment. The Dual-LUC experiment showed that ZmSOS1 was the target gene of ZmNAC59. [ Conclusion ] This study finds that ZmNAC59 activates ZmSOS1 promoter and regulates its expression to promote ion transport under salt stress , thereby improving plant salt resist- ance. This provides a basis for the screening of maize stress resistant genes and variety cultivation.

Background The status of patients with HIV/AIDS co-infected with HCV considerably varies in different parts of China. The co-infection of HIV and HCV accelerates the clinical progress of the disease, thereby reducing the patients' quality of life and exacerbating the occurrence of death. Currently, there are relatively few studies on patients with HIV/AIDS co-infected with HCV in Guizhou. Objective To analyze the status of patients with HIV/AIDS co-infected with HCV in Guizhou and its influencing factors and consequently provide basis for its early detection, diagnosis, and treatment. Methods The cases included in this study were a cohort of HIV/AIDS patients who received antiviral therapy (ART) in the public health rescue center of Guangzhou from March 2006 to December 2020. Finally, 3 084 patients who met the study requirements were included. Patients' sex, age, ethnicity, education level, occupation, marital status, route of infection, year of diagnosis, and CD4+ T-lymphocytes before ART and anti HCV levels were collected. Multivariate Logistic regression model were used to identify influencing factors of patients with HIV/AIDS co-infected with HCV. Results Among the 3 084 patients with HIV/AIDS, 202 were co-infected with HCV, and the co-infection rate was 6.55%. There were significant differences in HCV infection rates among patients with HIV/AIDS of different age groups, education levels, occupations, route of infection (P0.05) . The prevalence of HCV infection among HIV/AIDS patients tended to decrease with increasing year of diagnosis and increasing levels of CD4+ T lymphocytes (P

Chiral metal-organic frameworks (CMOFs),[Zn(L-mal)(H 2 O) 2 ] n were prepared by using zinc oxide instead of the traditional metal inorganic salt as the zinc source, and their chiral separation performance was investigated. Equal amounts of ZnO and L-malic acid were dissolved in H 2 O, and[Zn(L-mal)(H 2 O) 2 ] n were obtained by allowing the mixture to stand at room temperature for 24 h. Then, 100 mg[Zn(L-mal)(H 2 O) 2 ] n as the adsorbent was added to 250 μL 1 g/L 2,2'-furoin racemate, and 4.5 mL isopropanol and 1 mL methanol were selected as the extraction solvent and elution solvent, respectively, for selective adsorption experiments. The final filtrate was analyzed by high performance liquid chromatography (HPLC). The results showed that[Zn(L-mal)(H 2 O) 2 ] n exhibited better selective adsorption ability for R -2,2'-furoin with 20% enantiomeric excess (ee). This work provides a new method for the green preparation of CMOF and expands its application in the field of chiral separation.

Glycerol is a byproduct during biodiesel production. It is an important feedstock for fermentation due to its low price and high reduced status. Multiple genes of the glycerol utilization pathway were modulated in a previously engineered high β-carotene producing Escherichia coli strain CAR015 to enhance glycerol utilization capability for improving isoprenoids production. The glpR gene, encoding glycerol 3-phosphate repressor, was firstly deleted. The glpFK, glpD and tpiA genes were then modulated by three artificial regulatory parts, M1-37, M1-46 and M1-93, respectively. β-carotene titer reached 64.82 mg/L after modulating glpD with M1-46, which was 4.86 times higher than that of CAR015, and glycerol consumption rate also increased 100%. Modulating tpiA led to a little increase of β-carotene titer, whereas modulating glpFK led to a little decrease of β-carotene titer. This demonstrated that GlpD was a rate-limiting step in glycerol utilization pathway. Q-PCR of glpF, glpK, glpD and tpiA results showed that decrease the transcription level of glpF, glpK, glpD, or decrease the transcription level of tpiA could increase the cell growth and β-carotene production, probably for the decrease of methylglyoxal toxicity. Modulating glpD and tpiA genes in combination resulted in the best strain Gly003, which produced 72.45 mg/L β-carotene with a yield of 18.65 mg/g dry cell weight. The titer was 5.23 and yield 1.99 times of that of the parent strain CAR015. Our work suggested that appropriate activation of glpD and tpiA genes in glycerol utilization pathway could effectively improve β-carotene production. This strategy can be used for production of other terpenoids in E. coli.