The ppk-expressing transgenic rice floating bed improves P removal in slightly polluted water.

With significant economic advantages, the plant floating bed has been widely utilized in the ecological remediation of eutrophic water because of the excessive phosphorus (P) and nitrogen discharge in China. Previous research has demonstrated that polyphosphate kinase (ppk)-expressing transgenic rice (Oryza sativa L. ssp. japonica) (ETR) can increase the P absorption capacity to support rice growth and boost rice yield. In this study, the floating beds of ETR with single copy line (ETRS) and double copy line (ETRD) are built to investigate their capacity to remove aqueous P in slightly polluted water. Compared with the wild type Nipponbare (WT) floating bed, the ETR floating beds greatly reduce the total P concentration in slightly polluted water though the ETR floating beds have the same removal rates of chlorophyll-a, NO3--N, and total nitrogen in slightly polluted water. The P uptake rate of ETRD on the floating bed is 72.37% in slightly polluted water, which is higher than that of ETRS and WT on the floating beds. Polyphosphate (polyP) synthesis is a critical factor for the excessive phosphate uptake of ETR on the floating beds. The synthesis of polyP decreases the level of free intracellular phosphate (Pi) in ETR on the floating beds, simulating the phosphate starvation signaling. The OsPHR2 expression in the shoot and root of ETR on the floating bed increased, and the corresponding P metabolism gene expression in ETR was changed, which promoted Pi uptake by ETR in slightly polluted water. The Pi accumulation further promoted the growth of ETR on the floating beds. These findings highlight that the ETR floating beds, especially ETRD floating bed, have significant potential for P removal and can be exploited as a novel method for phytoremediation in slightly polluted water.

Amplified cyanobacterial bloom is derived by polyphosphate accumulation triggered by ultraviolet light.

Cyanobacterial blooms appear more strongly, constantly and globally, yet the positive effect of surface solar ultraviolet radiation (UV) on cyanobacterial bloom in natural freshwater habitats is largely ignored. Here in-situ and laboratory studies were jointly designed to probe the mechanism of cyanobacterial bloom promoted by solar UV light. The results showed that solar UV light is a key trigger factor for the accumulation of total phosphorus, dissolved inorganic phosphorus and polyphosphate (polyP) in blooming cyanobacterial cells. The increase of UV dose induces polyP accumulation to result in the excessive phosphorus uptake of blooming cyanobacteria, which provides sufficient phosphorus for cyanobacterial growth in suitable environment. Solar UV light also can promote the contents of phycocyanin, allophycocyanin, and phycoerythrin, producing sufficient ATP by photosynthesis for polyP synthesis in cyanobacterial cells in lake enviroment. The frequent variations of UV irradiance exposure prompts cyanobacteria to absorb excessive phosphorus from suspended solid or sediment. Cyanobacterial intracellular phosphorus is accumulated for their growth. UV light promotes polyP accumulation in blooming cyanobacterial cells to avoid damage. The adsorption amount of phosphorus increases for exuberant growth and then more surface blooming cyanobacteria are exposed to UV light to absorb ample phosphorus. Thus, the positive feedback occurs in lake water bodies with abundant phosphorus. This amplified cycle of cyanobacterial density and phosphorus due to solar UV light in eutrophic water bodies is analogous to a triode to amplify visible photosynthesis by UV light as a base electric current in the energy flow process in lake environment, therefore, "Cyanobacterial Phosphorus Assimilation Ultraviolet Effect" is used to describe this phenomenon. A new explanation is provided for the continuing proliferating mechanism of cyanobacterial bloom. Besides, a new perspective appears on the outbreak of cyanobacterial blooms in natural eutrophic lake water bodies worldwide.

Effects of biochar on the growth of Vallisneria natans in surface flow constructed wetland.

To improve the nitrogen and phosphorus removal efficiency of surface flow constructed wetlands (SFCWs), biochar was added to an SFCW matrix. The effects of adding different amounts of biochar on water purification, the growth of Vallisneria natans (V. natans), and microbial mechanisms were explored through SFCW simulation experiments. The results showed that through the joint action of biochar and V. natans, the concentrations of total nitrogen, total phosphorus, and ammonia nitrogen in the effluent significantly decreased. The total biomass, relative growth rate, and chlorophyll content of V. natans were significantly reduced by adding biochar (≥20%, v/v), as the root activity and the root to leaf biomass ratio slightly increased at first and then decreased. The carbon and nitrogen contents of V. natans slightly increased with the addition of biochar (≥10%, v/v), but the phosphorus content slightly decreased. Moreover, the nitrogen content of the matrices decreased significantly over time (P<0.05), and the phosphorus content in the matrix showed an increasing trend in the same period. In addition, the microbial 16S rDNA sequencing results indicated that the diversity and abundance of the microbial community in the matrix of the biochar-added SFCW tended to decrease. Nevertheless, the abundance of functional bacteria related to nitrogen and phosphorus removal (i.e., Pseudomonas and Dechloromonas) slightly increased, which would benefit denitrification and dephosphorization in the SFCW. Hence, the addition of biochar to the SFCW matrix facilitated the improvement of effluent water quality, while excessive biochar addition (≥10%, v/v) restrained the growth of V. natans but did not cause death. This conclusion provides valid data support regarding the ability of biochar-added SFCW to purify lightly contaminated water.

[Clinical efficacy of Matrine and Sodium Chloride Injection in treatment of 40 cases of COVID-19].

In this paper, we analyzed medical records of 40 patients with coronavirus disease 2019(COVID-19), in order to explore the clinical efficacy of Matrine and Sodium Chloride Injection in the treatment of COVID-19. The investigation was based on the results of a previous animal test, which was aimed to investigate and confirme the clinical efficacy of Matrine and Sodium Chloride Injection in the treatment of COVID-19. The animal test demonstrated that Matrine and Sodium Chloride Injection has a significant therapeutic effect on the human coronavirus pneumonia for the model mice. The lung inhibition index reached up to 86.86%. The evaluation was conducted on 40 confirmed cases of COVID-19 treated at Jingzhou Hospital of Infectious Disease(Chest Hospital) of Hubei Pro-vince from January 30~(th) to March 21~(th), 2020. In these cases, patients were treated with other integrated Chinese and Western medicines regimens in the recommended Matrine and Sodium Chloride Injection diagnosis and treatment regimen. The clinical manifestations, laboratory data, nucleic acid clearance time, and imaging data were compared and analyzed before and after treatment. After administration with Matrine and Sodium Chloride Injection, the clinical symptoms of 40 cases were alleviated markedly, and their blood analysis and biochemical indexes returned to normal. The lung CT showed more than 50% of lesion absorption rate, and the viral nucleic acid test showed the average clearance time of patients was 16.6 days, and the average length of hospital stay was 25.9 days. After administration with Matrine and Sodium Chloride Injection, the symptoms of cough and fatigue were alleviated significantly, and the appetite was significantly improved compared with before, especially for patients with gastrointestinal symptoms. Additionally, laboratory indicators, especially absolute value and ratio of lymphocytes and CRP were significantly alleviated. According to the chest CT for short-term review, the absorption of lung lesions was faster than before, especially for grid-like and fibrotic lesions. Compared with antiviral drugs, such as Abidol and Kriging, the nucleic acid clearance time was significantly shorter than the cases treated with Matrine and Sodium Chloride Injection. The clinical effective rate of 40 cases was 100.0%. We believed that Matrine and Sodium Chloride Injection have a good clinical effect in the treatment of COVID-19, and suggested increasing the clinical application and further conducting large-sample-size cli-nical verification.

Anticonvulsant and Neuroprotective Effects of Paeonol in Epileptic Rats.

Paeonol is the main active compound in the root bark extract of the peony tree, and it has antioxidative and anti-inflammatory effects. Recent studies have reported the neuroprotective effects of paeonol including its capacity in improving impaired memory. However, the effect of paeonol on epilepsy is yet to be demystified. We aimed to investigate the therapeutic effect of paeonol in epilepsy and its relationship with oxidative stress damage and neuronal loss in the rat brain to reveal the underlying mechanisms of epileptic seizures. A rat model for chronic epilepsy was established, and the seizure scores of the rats in different groups were recorded. The seizure duration and the seizure onset latency were used to evaluate the anticonvulsant effects of paeonol. Terminal deoxynucleotidyl transferase dUTP nick end-labeling staining, Nissl staining and H/E staining were used to evaluate the effects of paeonol on neuronal loss and apoptosis in epileptic rats. The colorimetric assessment of malondialdehyde (MDA) content, superoxide dismutase (SOD) activity, catalase activity and total antioxidant capacity of paeonol were used in assessing paeonol's effect on oxidative stress in epileptic rats. Evaluation of Caspase-3 mRNA and protein expression levels were determined using western blot and quantitative real-time (RT-q)PCR. In this study, we found that paeonol reduced the seizure scores of epileptic rats and attenuated the duration and onset latency of seizures. Paeonol can also increase the activities of total antioxidant capacity, SOD and catalase activity and reduce MDA content as well. This suggests that paeonol can improve the level of oxidative stress in rats. More significantly, paeonol can improve neuronal loss and apoptosis in epileptic rats. These results indicate that paeonol has anticonvulsant and neuroprotective effects in epileptic rats. This effect may be caused by reducing oxidative stress.

Immunomodulatory effect of Eriobotrya japonica seed extract on allergic dermatitis rats.

We examined the immunomodulatory effect of Eriobotrya japonica seed extract (ESE) on rat allergic dermatitis elicited by repeated dinitrofluorobenzene (DNFB) application on the ear. Oral administration of ESE significantly inhibited development of allergic dermatitis based on lower ear thickness and serum immunoglobulin E (IgE) levels. Th1 cytokine interferon-gamma (IFN-gamma) and interleukin-2 (IL-2), Th2 cytokine interleukin-4 (IL-4) and interleukin-10 (IL-10) in the lesional skin were determined. Oral administration of ESE significantly decreased IL-4 while significantly increasing IL-10 in lesional skin, and the lower levels of IFN-gamma and IL-2 were reversed by oral administration of ESE. The infiltration of eosinophils in the lesional skin was decreased by oral administration of ESE. These results suggested that ESE exerts anti-allergic actions by improving the balance of Th1/Th2 in allergic dermatitis.