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The root of Astragalus membranaceus (Fisch.) Bunge is one of the most frequently used herbs in traditional Chinese medicine (TCM) formulae for fighting COVID-19 infections, due to the presence of isoflavonoids and astragalosides associated with antiviral and immune-enhancing activities. For the first time, the exposure of A. membranaceus hairy root cultures (AMHRCs) to different colors of LED lights i.e., red, green, blue, red/green/blue (1/1/1, RGB), and white, was conducted to promote the root growth and accumulation of isoflavonoids and astragalosides. LED light treatment regardless of colors was found beneficial for root growth, which might be a result of the formation of more root hairs upon light stimulation. Blue LED light was found most effective for enhancing phytochemical accumulation. Results showed that the productivity of root biomass in blue-light grown AMHRCs with an initial inoculum size of 0.6% for 55 days was 1.40-fold higher than that in dark (control), and yields of high-value isoflavonoids and astragalosides including calycosin, formononetin, astragaloside IV, and astragaloside I increased by 3.17-fold, 2.66-fold, 1.78-fold, and 1.52-fold relative to control, respectively. Moreover, the photooxidative stress together with transcriptional activation of biosynthesis genes might contribute to the enhanced accumulation of isoflavonoids and astragalosides in blue-light grown AMHRCs. Overall, this work offered a feasible approach for obtaining higher yields of root biomass and medicinally important compounds in AMHRCs via the simple supplementation of blue LED light, which made blue-light grown AMHRCs industrially attractive as plant factory in controlled growing systems.

Germinated pigeon pea seeds (GPPSs) are good dietary supplements with satisfactory nutritional and medicinal values. In this study, UV-B treatment was used to promote the accumulation of health-promoting phenolic compounds (10 flavonoids and 1 stilbene) in GPPS. The total yield of 11 phenolic compounds (235 839.76 ± 17 118.24 ng/g DW) significantly improved (2.53-fold increase) in GPPSs exposed to UV-B radiation (3 W/m

As an important function for determining both the hydraulic and mechanical properties of soils, the soil–water characteristic curve (SWCC) based on the particle size distribution underestimates the water content at high suction head. In this study, the quantitative relationship between the clay content and residual pore fraction is established based on soil gradation parameters (uniformity coefficient C u and curvature coefficient C c ); the van Genuchten equation is employed to describe the soil–water characteristic curve; and then a semi-physical and semi-statistical method based on clay content is proposed to predict water-holding of unsaturated soils, especially for the soil with higher clay contents or low water contents (high matric suctions). Eighty-seven soil samples containing nine texture classes from the unsaturated soil hydraulic database (UNSODA) are used to verify the proposed approach. Two traditional models proposed by Hwang et al. (2011) and Meskini-Vishkaee et al. (2014) are introduced to compare the predictive effect with the improved method. Although three methods all show good performance, the improved prediction method based on uniformity coefficient ( C u = d 60 / d 10 ) has a better estimation accuracy than the two others according to statistical parameters, including root-mean-square error (RMSE), sum of square errors (SSE), and determination coefficient (R2). The ranking order of average uniformity coefficients in the three soil classes (sandy, silty, and clayey) agrees well with the ranking order of clay contents. Meanwhile, various d y / d x are used to characterize soil gradation and have similar goodness of fitting to residual pore fraction. In summary, the improved prediction model can effectively predict soil–water characteristic curves, especially for soil with low water contents (high matric suctions) or high clay contents. The model benefits the predictions of mechanical properties, permeability coefficient, shear strength and slope stability of unsaturated soil at low water contents.

Excessive nitrate in waterbody, which usually leads to eutrophication, can be removed by microbial denitrification processes. However, denitrification rate is greatly constrained by the spatial separation of nitrate in the upper oxic water layer from the electron donors close to the anoxic sediment. Herein, we constructed a genetically engineered bacterium (GEB), by co-expressing MO2.1 from Moringa oleifera and FLO5 from Saccharomyces cerevisiae, to simultaneously adsorb and self-flocculate nitrate from water. The GEB could migrate 45.5% of the nitrate to the bottom layer in actual water. Expressed FLO5 is electrically neutral and could trigger bacterial flocculation under the mediation of extracellular polysaccharides. Certain cationic arginine sites in MO2.1 can form strong electrostatic adsorption with NO3-, achieving bacterial self-flocculation, sedimentation and nitrate removal. The construction of multifunctional GEB could realize waterbody nitrate migration and is important to studies on new functional bacteria, water purification technology as well as geochemical nitrogen cycle.

The wetland macrophyte Hydrilla verticillata (L.f.) Royle was investigated for its hyperaccumulation potential and tolerance for the toxic metal cadmium (Cd) in a hydroponics experiment. H . verticillata was treated with 0 (control), 5, 10, 15, 20, and 40 μM of Cd, for 7, 14 and 21 days, respectively. The accumulation amounts of Cd in H . verticillata were extremely high, with maximum measured concentrations of 2220.0 and 1362.3 mg (kg −1 dw) in the leaves and stems, respectively. No significant reduction in biomass was observed as the Cd levels increased to 20 μM within 14 days; however, the protein content was much more sensitive to Cd. The growth status of the plants and the trajectory formed by fitting a curve to the metal accumulation process all suggest that a period of 14 days could be the time threshold for H . verticillata in treating Cd contamination with initial concentrations greater than 5 μM. Moreover, malondialdehyde (MDA) was used to measure the oxidative damage to the plants, and three antioxidant enzymes were used to test the plants’ tolerance to Cd. The MDA content and enzyme activity were closely correlated, and both responded strongly to Cd. At the same time, a positive defense strategy and high tolerance were observed, although the defensive mechanism lost efficacy at 20 and 40 μM after 14 days. Afterwards, regression analyses of initial Cd concentration and antioxidant enzyme activity on the 14th day were performed. The tolerable toxicity threshold for Cd in the water solution was within the range of 22.11–28.74 μM. These findings may be beneficial to Cd phytoremediation application and wetlands management.

Ceratophyllum demersum L. and Hydrilla verticillata (L.f.) Royle, two pioneer, submerged plants, effectively remove heavy metals from contaminated water. The present work evaluates the bioaccumulation and defense mechanisms of these plants in the accumulation of lead from contaminated water during their optimal performance period. C. demersum and H. verticillata were investigated after 14 days of exposure to various lead concentrations (5&ndash, 80 &mu, M). The lead accumulation in both C. demersum and H. verticillata increased with an increasing lead concentration, reaching maximum values of 2462.7 and 1792 mg kg&minus, 1 dw, respectively, at 80 &mu, M. The biomass and protein content decreased significantly in C. demersum when exposed to lead. The biomass of H. verticillata exposed to lead had no significant difference from that of the controls, and the protein content increased for the 5&ndash, 10 &mu, M exposure groups. The malondialdehyde (MDA) content and superoxide dismutase (SOD), peroxidase (POD), and polyphenol oxidase (PPO) activities were much higher in C. demersum, suggesting considerable damage from lipid peroxidation and sensitivity to lead stress. Enzyme inhibition and inactivation were also observed in C. demersum at high lead concentrations (40&ndash, M). The excellent growth status, low damage from lipid peroxidation, and high activity of catalase (CAT) and phenylalanine ammonia-lyase (PAL) observed in H. verticillata illustrate its better tolerance under the same lead stress.

A hydroponic study was conducted to investigate the lead bioaccumulation and tolerance characteristics of Ceratophyllum demersum L. exposed to various lead concentrations (5-80 μM) for 7, 14 or 21 days. Lead accumulation increased with increasing concentrations of metal in the solution, to a maximum accumulation of 4016.4 mg kg(-1) dw. Unexpectedly, the release of accumulated lead from the plants into solution was observed for all experimental groups except those exposed to 5 μM. Both the biomass and protein content of the plants responded significantly to lead stress. Malondialdehyde (MDA) levels increased substantially at lead concentrations below 20 μM, further indicating that this metal is toxic to the plants. To reveal the mechanism underlying the defense against lead stress, plants were also assayed for the activities of the antioxidant enzymes superoxide dismutase (SOD), catalase (CAT) and peroxidase (POD), as well as other relevant enzymes such as phenylalanine ammonia-lyase (PAL) and polyphenol oxidase (PPO). The activities of both SOD and CAT increased at lower lead concentrations and with shorter exposure times, followed by a decline, but the activities of POD and its isoenzymes continued to increase under all conditions. Moreover, increases in the activities of PAL and PPO were observed only for the 14-day treatment, and these two enzymes were not sensitive to lead concentration. These results suggest that C. demersum exhibits strong tolerance within a specific concentration range of lead in solution; according to regression analysis, 40 μM is suggested to be this plant's tolerance threshold for lead in water. Furthermore, the malfunction of this tolerance mechanism might accelerate the metal-release process. These attributes are likely to be beneficial for utilizing C. demersum in phytoremediation applications.

Heavy metal contamination of soil poses risks and hazards to environment and human being. Many amendments were used to remediate the contaminated soil. In this report, paper sludge was used to reduce the bioavailability of Pb in soil, and the remediation mechanism was studied by investigating the redistribution of Pb speciation after paper sludge addition. In pot experiments, significantly increased weights of shoots (from 1.6 to 3.3 mg per plant) and roots (from 0.7 to 0.8 mg per plant), as well as significantly decreased Pb content in shoots (from 153.8 to 24.4 mg kg−1) and roots (from 467.1 to 38.0 mg kg−1) of rape were observed after paper sludge was added. The addition of paper sludge resulted in redistribution of Pb from the liable fractions (carbonate-bound Pb from 58.3 to 3.7%) to the Fe–Mn oxide-bound fraction (from 29.2 to 74.9%). Paper sludge addition increased the content of organic matters and pH of soil, and induced Pb redistribution, which ultimately inhibited Pb uptake and improved...

Water contamination by nickel (Ni) has become an increasing concern in recent decades. Hydrilla verticillata (L.f.) Royle has been recognized as a promising accumulator of several potentially toxic elements (PTEs) in phytoremediation, but its Ni-accumulation characteristics and its mechanisms of tolerance to Ni remain largely unknown. This research investigated the biochemical responses of leaves and stems of H. verticillata to various concentrations of Ni (5, 10, 15, 20, and 40 μM) over periods of 7, 14, or 21 days. Plants accumulated considerable Ni to a maximum amount of 1080 mg kg-1 dry weight (DW) with a maximum bioconcentration factor of 1100; thus, high Ni accumulation was detected in H. verticillata. Low concentrations (5–15 μM) or short durations (less than 14 days) of Ni exposure might promote plant growth without adversely affecting normal metabolism. After peaking at day 14, a decline in bioaccumulation was unexpectedly observed as a long-term effect of Ni toxicity. Malondialdehyde content and the activities of defense-related enzymes changed in a similar pattern after treatment with Ni, increasing with both Ni concentration and exposure time to a peak (often at 5–15 μM on day 14), followed by a decline. Through a comprehensive analysis of all the test parameters, the tolerance thresholds were determined to be > 40.0 μM, 24.0 μM, and 15.8 μM at days 7, 14, and 21, respectively. Hydrilla verticillata could be a “high-potential accumulator” capable of decontaminating aquatic bodies polluted by Ni within the threshold range.

Object To investigate the imaging features of cavernous sinus cavernous hemangioma (CSCH) and evaluate the therapeutic effect of Gamma Knife radiosurgery (GKRS) in treatment of CSCH. Methods and materials Fifteen patients with CSCH treated by GKRS in our institute, including 6 males and 9 females, age range 20–77 years old, were analyzed retrospectively. Three of them were given craniotomies as the initial therapy. All cases had performed conventional and contrast-enhanced MRI and 5 patients underwent dynamic enhanced MRI preoperatively. In 6 cases, the multi-directional continuous data of axial, coronal and sagittal enhanced MRI were acquired. Three cases performed digital subtraction angiography (DSA) simultaneously. The diagnoses of lesions were determined mainly depending on typical imaging features. In 3 patients, the diagnoses of CSCH were confirmed histopathologically. The radiation dosimetry was done with a goal of conformal and selective coverage of the lesion with a 50% prescription isodose line. The mean marginal dose constituted 13.4 Gy (range 10–16 Gy). After GKRS was performed, all patients were arranged regular clinical and MRI follow-up every 6 months during the first 12 months, and once per year thereafter. Results On MRI, the lesions were typically demonstrated as iso/hypo-intensities on T1WI and remarkable hyper-intensities on T2WI, and apparent homogeneous enhancement. The phenomenon of dynamic enhancement was found in 11 cases. The progressive enhancing process from heterogeneous to uniform was displayed in the 5 patients performed same-slice dynamic MRI, including imaging characteristics of ‘edge to center’ enhancement in 2 case. In the other 6 cases, the delayed homogeneous enhancement of lesion was observed. Ten patients obtained radiological follow-up results after GKRS. Reviewing the follow-up data of 8 patients during the period of 3–6 months, the lesions were apparently shrunk in 5 patients with shrinkage rate of 20.8–46.8%. In 4 patients with imaging follow-up during the period of 6–12 months, the lesions of 3 patients were remarkably shrunk with shrinkage rate of 53.5–81.7%. Four patients had imaging follow-up data over 12 months, and all their lesion sizes were reduced with shrinkage rate of 19–83.6%. The clinical presentations of all patients after GKRS were followed up during the period of 1–30 months. In 7 of 9 cases with headache, the symptom was improved; in 5 of 6 cases, facial hypesthesia was improved; in 6 of 9 cases with visual impairments, the visions were markedly improved; and in 8 cases with preoperative diplopia, the symptoms were all resolved. Conclusion Although bright hyper-intensities on T2WI and significant homogeneous enhancement on contrast-enhanced T1WI are considered as typical imaging characteristics of CSCH, the dynamic process of progressive delayed enhancement on contrast-enhanced MR is more persuasive in diagnosis. According to our study, GKRS could be chosen as an effective and safe alternative treatment for CSCH. We consider that using relatively low marginal dose may get better effects in tumor shrinkage and protection of cranial nerves.

The Al tridecamer (Al13) is the most active species in Al-based coagulant. Solid Al13 samples with high purity can be separated and purified using an ethanol–acetone fractional precipitation method. In this paper, we present the characterization of the stability of solid Al13 under different storage conditions as well as the performance and behavior during the coagulation process. The results show that solid Al13 has good solubility and stability, and the original distribution of the Al species and the Al13 content can be maintained stably during the dissolution, dilution and storage processes. During the studied storage period, either as liquids or solids, the Al13 neither degrades nor polymerizes. The Al13 is prone to aggregation at high concentrations, but the aggregates dissociate rapidly upon dilution. Compared with other Al species, the Al13 has better charge-neutralizing ability and can destabilize particles suspended in water more rapidly. The Al13 can decrease the optimum dosage, improving the coagulation performance at lower dosages. The coagulation mechanism of Al13 depends on its dosage and the coagulation pH, and is dominated by the charge-neutralization and enmeshing–sweeping mechanisms.

Pot experiments were performed to investigate the responses of nitrogen metabolism to copper stress in Luffa cylindrica roots. Four treatments were used, in which varying copper concentrations (25, 50, 75 and 100 μM) were added to MS medium. The fresh weights of the roots decreased gradually with the increasing copper concentrations. At the lower concentrations, the ammonium and nitrite levels increased compared with the control, but the nitrate concentrations significantly decreased with 75 and 100 μM copper. Compared with the control, nitrate reductase activity levels gradually increased with increasing copper concentrations of up to 50 μM, and nitrite reductase activity levels significantly decreased. Copper stress led to variable increases in the activities of glutamine synthetase and glutamate synthase compared with the controls. The NADH- glutamate dehydrogenase (NADH-GDH) and NAD-glutamate dehydrogenase (NAD-GDH) activities were affected by the copper treatments, but that of NAD-GDH was significantly reduced by 100 μM copper. The activities of alanine aminotransferase (AlaAT) and aspartate aminotransferase (AspAT) showed varying changes following the copper treatments. The present results indicate that Luffa cylindrica shows altered activities of enzymes associated with nitrogen metabolism during copper stress, enabling it to monitor and adapt to changes in its N status and supply, thereby minimizing the harmful effects of the stress.

AIM To evaluate the utility of 3D-magnetic resonance cisternography(MRC) of posterior cranial fossa in visualizing trigeminal neurovascular compression in patients with trigeminal neuralgia. MATERIAL AND METHODS 146 consecutive patients in the period from June 2010 to July 2011 in our institute diagnosed with trigeminal neuralgia underwent MRC on the posterior cranial fossa. MR devices used for MRC included two sets of 3.0 tesla and one set of 1.5 tesla. The hydrography sequences for MRC included 3D-SPACE and 3D-DRIVE. RESULTS In total, 75 patients (51.4%) were found with trigeminal neurovascular compression on MRC. Among them, 25 patients underwent microvascular decompression. Intraoperatively, 20 patients (80%) had related arteries consistent with imaging manifestations on MRC. Nevertheless, the arterial compression combined with petrosal vein could not be identified on MRC in 3 of the 20 patients. In the inconsistent 5 cases, the involved vessels were confirmed as superior petrosal veins during the surgery. CONCLUSION 3D-MRC has prominent clinical value in determining the trigeminal neurovascular compression and identifying the related vessels. However, MRC does have certain limitations on identifying petrosal vein compression.

A novel hybrid hydrogel was prepared and investigated based on silkworm silk fibroin and poly(N-isopropylacrylamide) (PNIPAAm). PNIPAAm was introduced to silk fibroin, the resultant composite hydrogel was examined, and freeze-dried SF/PNIPAAm scaffold was analyzed using LB-550 dynamic light scattering particle-size analyzer, circular dichroism (CD), and scanning electron microscopy (SEM). Our results suggested that the hybrid hydrogels owned the porous sponge-like structures, and the gelation time of SF/PNIPAAm hybrids decreased with an increase in temperature and concentration of each polymer. Results of rheological analysis suggested that the rheological property of resultant SF/PNIPAAm gel depended on the concentration combinations as well as the aging time, which elapsed after mixing the two polymers. Results of CD spectra demonstrated that pH showed little influence on the secondary structure of silk fibroin, and significant changes of , , and G* as surrounding increase temperature above the lower critical solution temperature (LCST).