Foliar zinc spraying improves assimilative capacity of sugar beet leaves by promoting magnesium and calcium uptake and enhancing photochemical performance.

Sugar beet, a zinc-loving crop, is increasingly limited by zinc deficiency worldwide. Foliar zinc application is an effective and convenient way to supplement zinc fertilizer. However, the regulatory mechanism of foliar zinc spraying on sugar beet leaf photosynthetic characteristics remains unclear. Therefore, we investigated the effects of foliar ZnSO4·7H2O application (0, 0.1%, 0.2%, and 0.4%) on the photosynthetic performance of sugar beet leaves under controlled hydroponic conditions. The results indicated that a foliar spray of 0.2% Zn fertilizer was optimal for promoting sugar beet leaf growth. This concentration significantly reduced the leaf shape index of sugar beet, notably increasing leaf area, leaf mass ratio, and specific leaf weight. Foliar spraying of Zn (0.2%) substantially elevated the Zn content in sugar beet leaves, along with calcium (Ca) and magnesium (Mg) contents. Consequently, this led to an increase in the potential photochemical activity of PSII (Fv/Fo) (by 6.74%), net photosynthetic rate (Pn) (11.39%), apparent electron transport rate (ETR) (11.43%), actual photochemical efficiency of PSⅡ (Y (Ⅱ)) (11.46%), photochemical quenching coefficient (qP) (15.49%), and total chlorophyll content (25.17%). Ultimately, this increased sugar beet leaf dry matter weight (11.30%). In the cultivation and management of sugar beet, the application of 0.2% Zn fertilizer (2.88 mg plant-1) exhibited the potential to enhance Zn and Mg contents in sugar beet, improve photochemical properties, stimulate leaf growth, and boost light assimilation capacity. Our result suggested the foliar application of Zn might be a useful strategy for sugar beet crop management.

Application of Se-Met to CdTe QDs significantly reduces toxicity by modulating redox balance and inhibiting apoptosis.

Cadmium tellurium quantum dots (CdTe QDs) as one of the most widely used QDs have been reported the toxicity and biosafety in recent years, little work has been done to reduce their toxicity however. Based on the mechanisms of toxicity of CdTe QDs on liver target organs such as oxidative stress and apoptosis previously reported by other researchers, we investigated the mechanism of action of trace element selenium (Se) to mitigate the hepatotoxicity of CdTe QDs. The experimental results showed that Se-Met at 40-140 µg L-1 could enhance the function of intracellular antioxidant defense system and the molecular structure of related antioxidant enzymes by reduce the production of ROS by 45%, protecting the activity of antioxidants and up-regulating the expression of selenoproteins with antioxidant functions, Gpx1 increase 225% and Gpx4 upregulated 47%. In addition, Se-Met could alleviate CdTe QDs-induced apoptosis by regulating two apoptosis-inducing factors, as intracellular caspase 3/9 expression levels were reduced by 70% and 87%, decreased Ca2+ concentration, and increased mitochondrial membrane potential measurements. Overall, this study indicates that Se-Met has a significant protective effect on the hepatotoxicity of CdTe QDs. Se-Met can be applied to the preparation of CdTe QDs to inhibit its toxicity and break the application limitation.

Clinical and radiologic features of the first cured Coronavirus disease 2019 (COVID-19) patient in Guangzhou City, China.

To determine changes in clinical and radiologic findings associated with Coronavirus disease 2019 (COVID-19) from diagnosis to recovery, we retrospectively reviewed the diagnosis and treatment records of the first patient cured of COVID-19 in Guangzhou. A 55-year-old woman from Wuhan was admitted to the hospital isolation ward with the chief complaint of "cough for 11 days and once fever 8 days ago" on January 22, 2020. COVID-19 was laboratory confirmed by reverse transcription polymerase chain reaction (RT-PCR) assay, and she received conventional antiviral therapy, such as moxifloxacin, traditional Chinese medicine, and arbidol. Repeat chest-computed tomography (CT) scans were performed on days 13 and 19 of her illness. The former showed radiologic findings, including ground-glass opacities (GGOs), which revealed viral pneumonia; the latter revealed that the previous lesions had been significantly absorbed. The lesions on CT scans were consistent with the changes in the course of disease. Some drugs, such as traditional Chinese medicine and arbidol, might play an important role in the recovery of COVID-19 patients. This study provides some new insights into the formulation of a timely and effective diagnostic and therapeutic strategy to cure patients with COVID-19.

[Apoptosis and activity changes of telomerase induced by essential oil from pine needles in HepG2 cell line].

OBJECTIVE: To study the effects of essential oil extracted from pine needles on HepG2 cell line. METHODS: HepG2 cells were treated with essential oil extracted from pine needles. Cell growth rate was determined with MTF assay, cell morphologic changes were examined under transmission electromicroscope and HE straining. Flow cytometry was used to exmine apoptotic cells. Bcl-2 gene expression was determined by flow cytometry and telomerase activity by TRAP assay. RESULTS: Essential oils from pine needles could not only repress the growth of HepG2 cells significantly, but also induce apoptosis to them. Both dose-effect and time-effect relationship could be confirmed. Typical morphology changes of apoptosis such as nuclear enrichment and karyorrhexis were observed through transmission electromicroscope and HE straining. Telomerase activity was down regulated in the essential oil extracted from pine needles induced apoptotic cells. The expression of bcl-2 gene was suppressed after the essential oil from pine needles treatement. CONCLUSION: The essential oil extracted from pine needles can inhibit cell growth of HepG2 cell line and induce apoptosis, which may associate with inhibition of telomerase activity and bcl-2 may be involved in the regulation of telomerase activity.