Oxidation-Resistant Silicon Nanosystem for Intelligent Controlled Ferrous Foliar Delivery to Crops.

Since ferrous (Fe(II)) is the main form of plant absorption, traditional ferrous foliar fertilizers (TFFF) are widely used in modern agriculture. However, TFFF suffer from the shortcomings of weak antioxidant capacity (AC), low foliar adhesion efficiency (FAE), poor fertilizer utilization efficiency (FUE), and noncontrollable slow-release behavior. To overcome these limitations, an oxidation-resistant silicon nanosystem for intelligent controlled ferrous foliar delivery to crops was first developed by using environmentally friendly micro/nano structured hollow silicon as carrier, and combining with vitamin C (in situ antioxidant) to synthesize an oxidation-resistant ferrous foliar fertilizer (ORFFF) for ameliorating Fe-deficiency in crops and increasing crop yield. Compared with TFFF, the ORFFF has excellent ferrous AC (only 11.5% of Fe(II) was oxidized in ORFFF within 72 h), ultrahigh FAE (∼84% of adhesion percentage (%) after two-times simulated rain rinsing), nutrient slow-release ability (720 h gradually release 100.6 mg·g-1), pH-controlled release ability (pH 3-8), and verified high biological safety (100% survival rate for zebrafish and earthworm). The pot experiments showed that ORFFF can correct the Fe-deficiency symptoms of tomato seedlings promptly compared with TFFF, and the FUE of ORFFF is 4.2 times that of TFFF. The specific pH responsiveness of ORFFF can control the slow-release rate of Fe(II) to satisfy the needs of Fe in varying crops and different growing periods of crops. This work provides a feasible way to achieve green and safe Fe supplementation for crops, reduce Fe fertilizer waste, avoid soil pollution caused by Fe fertilizer abuse, and promote the sustainable development of modern nanoagriculture.

Zirconium metal organic frameworks-based DGT technique for in situ measurement of dissolved reactive phosphorus in waters.

In an effort to provide early warnings for the occurrence of eutrophication, it is highly desirable to develop an accurate and efficient technique to ensure continuous monitoring of dissolved reactive phosphorus (DRP) in the aquatic environment from the viewpoint of environmental management. Herein, a new diffusive gradient in thin film (DGT) technique was developed and evaluated for in situ measurement of DRP in waters, in which Zr-based metal organic frameworks (MOFs, UiO-66) were utilized as aqueous binding agent (abbreviated as UiO-66 DGT). As expected, the UiO-66 DGT demonstrated high uptake capacity towards phosphorus (20.8 µg P cm-2). Meanwhile, an excellent linearity between the accumulated DRP mass and deployment time over 5 d (R2 = 0.996) was obtained regardless of high or low phosphate solution. In addition, effective diffusion coefficients (D) of DRP increased exponentially with increasing ionic strengths (R2 = 0.99). Based on the rectified D, the performance of the UiO-66 DGT was independent of solution pH (6.5-8.5) and ionic strengths (ranging from 0.01 to 100 mmol L-1). Furthermore, field deployments of the UiO-66 DGT were undertaken in a natural eutrophic lake (Lake Chaohu, China). It was noteworthy that DRP could be continually accumulated by the UiO-66 DGT for more than 14 d and good agreements were obtained between the concentrations measured by DGT (CDGT) and those by ex situ chemical extraction method in solution (Csol), as reflected by CDGT/Csol of 0.9-1.1. In situ determination of DRP speciation was also carried out at different sites across Lake Chaohu. Overall, this study contributed to a better constructing of liquid binding phase DGT for the measurement of DRP in waters, facilitating the widespread application of the UiO-66 DGT as a routine monitoring technique and for large-scale environmental analysis.

[Effect of Resveratrol on Isoproterenol Induced Cardiomyocyte Apoptosis Rats].

OBJECTIVE: To observe the effect and mechanism of resveratrol (Res) on isoprotere- nol (ISO) induced cardiomyocyte apoptosis rats. METHODS: Primary cultured neonatal cardiomyocyte ap- optosis rat model was established using ISO. Apoptosis cells were then randomly divided into 4 groups, i. e., the normal control group (non-serum DMEM culture fluid) , the model group (non-serum DMEM culture fluid + ISO 1 µmol/L for 48 h) , the Res + ISO group (ISO 1 µmol/L + Res 50 µmoI/L for 48 h) , the Res control group. (non-serum DMEM culture fluid + Res 50 l_mol/L). The apoptosis rate was measured by Hochest33258 staining. Ultrastructural changes of cardiomyocyte were observed by electron microscope. Leakage of lactate dehydrogenase (LDH) in the culture fluid was measured. Protein expressions of BcI-2 and Bax were detected using Western blot. Results The count of cardiomyocytes were reduced and the nucleus shape was irregular. The apoptosis bodies were visible and the apoptosis rate was increased in the model group. The cell membrane was complete with clear nuclear membrane in the Res + ISO group and the Res control group. Nuclear chromatin was concentrated and cell injured degree was attenuated in the Res +ISO group and the Res control group. Compared with the normal control group, the apoptosis rate and LDH leakage increased, the protein expression of Bcl-2 was down-regulated, and the expression of Bax was up-regulated in the model group (P <0. 05, P <0. 01). Compared with the model group, the apoptosis rate and LDH leakage decreased, the protein expression of Bcl-2 was up-regulated, and the expression of Bax was down-regulated in the Res + ISO group and the Res control group (P <0. 05). CONCLUSION: Res could obviously attenuate ISO induced cardiomyocyte apoptosis, and its mechanism might be associated with reversing protein expressions of Bcl-2 and Bax.

Hyperbaric oxygen alleviates experimental (spinal cord) injury by downregulating HMGB1/NF-κB expression.

STUDY DESIGN: We presented an insight into the effect of hyperbaric oxygen (HBO) on spinal cord injury (SCI), aiming to uncover the dynamics of high-mobility group protein B1 (HMGB1) and nuclear factor κB (NF-κB) after HBO intervention in rats with acute SCI. OBJECTIVE: Prognosis of SCI is directly linked with the control of secondary injury, in which the inflammatory response plays a leading role. HBO therapy can reduce this secondary damage to the spinal cord. We used an animal model to characterize the therapeutic effect of HBO on SCI. SUMMARY OF BACKGROUND DATA: A growing number of studies have confirmed that HBO has gradually become an indispensable element after SCI in reducing neurological disorders, and improving the physical function and quality of life of patients. The role of HBO in the process of HMGB1/NF-κB-related secondary inflammatory responses in SCI has yet to be characterized. METHODS: Rats were randomly categorized into sham, sham + HBO, SCI, and SCI + HBO groups. The expression levels of HMGB1 and NF-κB were measured at days 1, 3, 7, and 14 after SCI. RESULTS: After SCI, significant increases in mRNA and protein expression were observed for both HMGB1 and NF-κB (P< 0.01) compared with sham group. HMGB1 mRNA and protein expression levels were decreased after HBO intervention. The decreases were significant at days 7 and 14 (P< 0.05) post-HBO. In the SCI + HBO group, the significant decreases in NF-κB mRNA and protein expression levels were also observed at days 3, 7, and 14 (P< 0.05). After HBO intervention, a significant increase was seen in the Basso, Beattie, and Bresnahan score at days 7 and 14 (P< 0.05). CONCLUSION: HBO intervention may reduce the secondary damage of SCI caused by inflammatory responses via downregulating the expression of HMGB1/NF-κB, and promoting the repair of neurological function. LEVEL OF EVIDENCE: N/A.

Effects of hyperbaric oxygen on MMP-2 and MMP-9 expression and spinal cord edema after spinal cord injury.

AIMS: To evaluate the effects of hyperbaric oxygen (HBO) therapy on MMP-2 and MMP-9 expression and spinal cord edema after acute spinal cord injury (SCI). MAIN METHODS: Ninety-six healthy adult Sprague − Dawley rats were randomly divided into 4 groups: sham, sham + HBO, SCI, and SCI + HBO. Each group was subdivided into 4 subgroups of 6 rats each: 24 h, 48 h, 72 h, and 5 d post-injury. The expression levels of matrix metalloproteinase-2 (MMP-2), MMP-9, interleukin (IL-6), and vascular endothelial growth factor (VEGF) were measured using ELISA. The water content of the spinal cord was also measured by Elliot equation. KEY FINDING: MMP-2 and MMP-9 levels and spinal cord water content increased significantly in the SCI group compared to those in the sham and sham + HBO groups at different time points after SCI (P < 0.01). The MMP-2 level was significantly different between the SCI and SCI + HBO groups at 72 h after SCI (P < 0.05), while the MMP-9 level was significantly different at 48 h, 72 h, and 5 d (P < 0.05). The water content of the spinal cord was significantly higher in the SCI group at 5 d after SCI (P < 0. 01). MMP-2 (P < 0.05) and MMP-9 (P < 0.01) levels were positively correlated with spinal cord water content. SIGNIFICANCE: HBO reduced SCI-induced spinal cord edema, stabilized the blood-spinal cord barrier, and promoted recovery of neuronal function by down regulating the expression of IL-6, MMP-2, and MMP-9 and up regulating the expression of VEGF.

Short term effect of Salvia miltiorrhiza in treating rat acetic acid chronic gastric ulcer and long term effect in preventing recurrence.

AIM:To study the short-term effect of Danshen (Salvia miltiorrhiza) on acetic acid induced chronic gastric ulcer in rats and its long-term effect in preventing recurrence.METHODS:Rats with acetic acid-induced gastric ulcer were treated with Danshen and cimetidine for 30 days.Traditional gastric mucosal auto-radiography and (3)H-TdR incorporation into gastric mucosa in vitro were employed to study the effects of Danshen in rat acetic acid-induced chronic gastric ulcer, including ulcer index (UI), ulcer inhibitory rate (IR) and label rate (LR).RESULTS:On the day 5, 30 and 126 of ulcer-making, the UI in the Danshen group was obviously lower than that in the cimetidine group and the control group (42.3 ± 3.9, 3.6 ± 1.2, 4.4 ± 2.3; 49.1 ± 3.6, 5.9 ± 1.4, 9.2 ± 1.3; 61.0 ± 3.8, 8.9 ± 2.5, 12.4 ± 2.4, respectively, P < 0.01), the IR (%) in the Danshen group was obviously higher than that in the cimetidine group (31, 59, 64.8; 19, 33, 26, respectively), and the LR in the Danshen group was obviously higher than that in the cimetidine group and the control group (10.0 ± 0.5,16.2 ± 0.8, 15.0 ± 0.6; 9.0 ± 0.5, 13.9 ± 0.6, 10.8 ± 0.7; 6.5 ± 0.7, 10.1 ± 0.5, 8.0 ± 0.7, respectively, P < 0.01). There was no obvious difference in UI in the Danshen group on day 30 as compared with that on day 126.CONCLUSION:Danshen is effective in promoting ulcer healing and preventing recurrence. The mechanism of action is to strengthen the gastric mucosal barrier and to promote the gastric mucosal cell proliferation along the edge of the ulcer.