Mechanistic insights into dissolved organic matter-driven protistan and bacterial community dynamics influenced by vegetation restoration.

Vegetation restoration projects can not only improve water quality by absorbing and transferring pollutants and nutrients from non-vegetation sources, but also protect biodiversity by providing habitat for biological growth. However, the mechanism of the protistan and bacterial assembly processes in the vegetation restoration project were rarely explored. To address this, based on 18 S rRNA and 16 S rRNA high-throughput sequencing, we investigated the mechanism of protistan and bacterial community assembly processes, environmental conditions, and microbial interactions in the rivers with (out) vegetation restoration. The results indicated that the deterministic process dominated the protistan and bacterial community assembly (94.29% and 92.38%), influenced by biotic and abiotic factors. For biotic factors, microbial network connectivity was higher in the vegetation zone (average degree = 20.34) than in the bare zone (average degree = 11.00). For abiotic factors, the concentration of dissolved organic carbon ([DOC]) was the most important environmental factor affecting the microbial community composition. [DOC] was lower significantly in vegetation zone (18.65 ± 6.34 mg/L) than in the bare zone (28.22 ± 4.82 mg/L). In overlying water, vegetation restoration upregulated the protein-like fluorescence components (C1 and C2) by 1.26 and 1.01-folds and downregulated the terrestrial humic-like fluorescence components (C3 and C4) by 0.54 and 0.55-folds, respectively. The different DOM components guided bacteria and protists to select different interactive relationships. The protein-like DOM components led to bacterial competition, whereas the humus-like DOM components resulted in protistan competition. Finally, the structural equation model was established to explain that DOM components can affect protistan and bacterial diversity by providing substrates, facilitating microbial interactions, and promoting nutrient input. In general, our study provides insights into the responses of vegetation restored ecosystems to the dynamics and interactives in the anthropogenically influenced river and evaluates the ecological restoration performance of vegetation restoration from a molecular biology perspective.

Inhibitory effects of essential oil from rhizomes of Ligusticum chuanxiong on hypertrophic scarring in the rabbit ear model.

CONTEXT: Hypertrophic scarring, a common proliferative disorder of dermal fibroblasts, results from an overproduction of collagen and excessive deposition of extracellular matrix. Although the treatment with surgical excisions or steroid hormones can modify the symptoms, numerous treatment-related complications have also been established. OBJECTIVE: To investigate the effects of essential oil (EO) from rhizomes of Ligusticum chuanxiong Hort. (Umbelliferae) on hypertrophic scarring in a rabbit ear model. MATERIALS AND METHODS: A rabbit ear model of hypertrophic scarring was established. EO (5, 10, and 20%) was applied once daily to the scars for 22 days. After 28 days of post-wounding, excision of scars was respectively performed for both histological examination and assays of the levels of collagen I, collagen III, matrix metalloproteinase-1 (MMP-1), and transforming growth factor beta 1 (TGF-ß1). The scar elevation index (SEI) was also determined. RESULTS: After 22 days of treatment with indicated concentrations of EO, hypertrophic scarring was significantly inhibited in the rabbit ears. The levels of TGF-ß1, collagen I, and collagen III evidently decreased and MMP-1 level markedly increased in the scar tissue. SEI was also significantly reduced. Immunohistochemical findings exhibited significant amelioration of the scar tissue. DISCUSSION AND CONCLUSION: EO suppresses hypertrophic scarring in the rabbit ear model and is a probably effective cure for human hypertrophic scarring.

Establishment of a luciferase assay-based screening system for detecting estrogen receptor agonists in plant extracts.

In order to effectively treat osteoporosis and other bone-loss disorders, small compounds that could induce bone formation are needed. The present study attempted to establish a screening system for detecting estrogenic activity of compounds, which probably have anti-osteoporosis effects. For this purpose, we established osteoblastic-like MG63 cells stably transfected with the PGL3 reporter gene driven by a promoter consisting of three estrogen response elements (EREs). Using this system, we screened numerous plant extracts, and found several which displayed bioactivity. We conclude that the MG63 cells with estrogen-specific reporter plasmids (MG63-pERE) are useful for high-throughput screening of estrogen receptor agonists from plants which may have favorable potency and could be developed into novel anti-osteoporosis drugs.

Essential oil from rhizomes of Ligusticum chuanxiong induces apoptosis in hypertrophic scar fibroblasts.

CONTEXT: Hypertrophic scarring following surgical procedures, trauma and especially burns can lead to severe functional and cosmetic impairment, causing a decrease in the quality of life. Although a wide choice of treatments is offered, few therapeutic methods are universally accepted because of their side effects. OBJECTIVE: The effects of the essential oil (EO) extracted from rhizomes of Ligusticum chuanxiong Hort. (Umbelliferae) in human hypertrophic scar fibroblasts (HSFs) are investigated for the first time. MATERIALS AND METHODS: Chemical composition of hydrodistilled EO obtained from rhizomes of Ligusticum chuanxiong was analyzed by gas chromatography-mass spectrometry (GC-MS). The effects of EO on cell viability, apoptosis rate, mitochondrial membrane potential (MMP), lactate dehydrogenase (LDH), reactive oxygen species (ROS) and caspase-3 in HSFs were investigated. RESULTS: The experimental results showed that EO significantly inhibited cell viability, elicited morphological changes and induced apoptosis in HSFs. EO also evidently increased the loss of MMP, the levels of LDH release and cellular ROS production, and the activity of caspase-3. DISCUSSION AND CONCLUSION: EO-induced apoptosis was at least partially carried out via destruction of the intracellular antioxidant system and elicitation of excessive ROS accumulation in HSFs, which impaired mitochondrial membranes and elicited caspase-3 activation. EO could be an effective cure for human hypertrophic scar.

[Simultaneous phosphorus and nitrogen removal of domestic sewage with aerobic granular sludge SBR].

By seeding aerobic granular sludge cultivated from artificial wastewater, an anaerobic/aerobic SBR was applied to treat domestic sewage of high COD, TN and SS. The stability of granular sludge and the removal of organic pollutants, nitrogen and phosphorus of domestic sewage were investigated. After one month incubation, the reactor had good pollutant removal performances and run stably. The ratio of granular sludge to total suspended solids was over 68% all along. The sludge concentration was 5 000 - 6 000 mg/L and SVI value was 20 - 35 mL/g. After three months operation, most of the granules were over 1.25 mm instead of 0.6 - 0.9 mm in the beginning. During the stable operation phase of the granular sludge SBR, the average removal efficiencies of COD, TOC, phosphate, ammonium nitrogen, total nitrogen, SS were 83.04%, 70.41%, 94.30%, 86.51%, 41.82% and 85.89%, respectively. Analysis of the pollutant removal in typical cycle showed that the granular sludge had good simultaneous phosphorus and nitrogen removal performance.