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Dissolved organic matter (DOM) plays a non-negligible role in the indirect photodegradation of organic contaminants. This research investigated the roles of DOM and the environmental factors (salinity, pH, NO3−, and HCO3−) in the indirect photodegradation of ofloxacin (OFX) in simulated seawater. Results showed that DOM can significantly accelerate the indirect photodegradation of OFX, and 1O2 and 3DOM* were the main reactive intermediates (RIs) that could promote the indirect photodegradation of OFX. Fluorescence excitation–emission matrix spectroscopy–parallel factor analysis (EEMs-PARAFAC) was used to divide DOM into four fluorescence components. The indirect photodegradation rate of OFX was affected by DOM structure, and terrigenous DOM usually produced more RIs to promote the indirect photodegradation of OFX. Increased salinity significantly promotes the indirect photodegradation of OFX, while increased NO3− concentration had no effect on the OFX indirect photodegradation. pH affected the formation of RIs and the structure of OFX, thereby affecting the indirect photodegradation of OFX. The indirect photodegradation rate of OFX increased in the HCO3− solution, which is due to the formation of carbonate radical (CO3−). This study is essential in understanding the role of DOM in OFX indirect photodegradation and providing a novel insight into the fate, removal, and transformation of OFX.

Abstract The ecotoxicological effects of Ciprofloxacin hydrochloride (CIP) were tested on population densities of plankton assemblages consisting of two algae (Isochrysis galbana and Platymonas subcordiformis) and a rotifer (Brachionus plicatilis). The I. galbana showed a significant decrease in densities when concentrations of CIP were above 2.0 mg L−1 in single-species tests, while P. subcordiformis and B. plicatilis were stable in densities when CIP were less than10.0 mg L−1. The equilibrium densities of I. galbana in community test increased with CIP concentrations after falling to a trough at 5.0 mg L−1, showed a completely different pattern of P. subcordiformis which decreased with CIP concentrations after reaching a peak at 30.0 mg L−1. The observed beneficial effect was a result of interspecies interactions of trophic cascade that buffered for more severe direct effects of toxicants. The community test-based NOEC of CIP (2.0 mg L−1), embodying the indirect effects, was different from the extrapolated one derived by single-species tests (0.5 mg L−1), but all lacked confidence interval. A CIP threshold concentration of obvious relevance to ecological interaction was calculated with a simplified plankton ecological model, achieving a value of 1.26 mg L−1 with a 95% bootstrapping confidence interval from 1.18 to 1.31 mg L−1.

Abstract Background Influences of atorvastatin on atherosclerosis and glycemic metabolism may be related to its potential impact on circulating adiponectin, an adipocyte that exerts anti-inflammatory, ant-atherosclerotic, and anti-oxidative effects. However, results of previous randomized controlled trials (RCTs) were not consistent. We performed a meta-analysis of RCTs to systematic evaluate the influence of atorvastatin on circulating adiponectin. Methods Relevant studies were identified via search of electronic databases of PubMed, Embase, and Cochrane’s Library. A random-effect model was applied to pool the results via incorporating the potential heterogeneity. Predefined meta-regression and subgroup analyses were used to evaluate the influences of study characteristics on the outcome. Results Fourteen datasets from ten RCTs including 931 patients were included. Pooled results showed that atorvastatin did not significantly affect circulating adiponectin as compared with controls (weighed mean difference = − 0.27 μg/mL, 95% confidence interval: − 0.89 to 0.35 μg/mL, p = 0.39). Results of univariate meta-regression analyses showed that study characteristics including number of patients, mean age, proportion of male patients, body mass index, dose of atorvastatin, or treatment duration did not significantly affect the outcome (p all > 0.05). Moreover, subgroup analyses showed that atorvastatin did not significantly affect circulating adiponectin in studies stratified according to these study characteristics (p all > 0.05). Conclusions Atorvastatin treatment does not significantly affect circulating adiponectin. Influences of atorvastatin on atherosclerosis and glycemic metabolism are not likely to be mediated by modulation of circulating adiponectin.

Long non-coding RNAs (lncRNAs) have been reported to be crucial modulators in various heart diseases, including myocardial infarction (MI). LncRNA metastasis associated lung adenocarcinoma transcript 1 (MALAT1) has been reported to be highly expressed in MI samples. However, the mechanism and biological function of MALAT1 in myocardial infarction are still marked. Similarly, programmed cell death 4 (PDCD4) was also upregulated in MI samples. Therefore, MALAT1 and PDCD4 were chosen to do further study. At first, qRT-PCR was applied to examine the expression patterns of MALAT1 and PDCD4. The results showed that both MALAT1 and PDCD4 were upregulated in MI mice model and the hypoxia-induced myocardial cell. Subsequently, loss-of function assays were conducted to examine the impacts of MALAT1 or PDCD4 on cellular processes. Results of MTT assay and flow cytometry analyses manifested that knockdown of MALAT1 or PDCD4 enhanced cell viability, promoted cell cycle progress and suppressed cell apoptosis. Transferase-mediated dUTP nick end labeling (TUNEL) assay revealed that MALAT1 knockdown or PDCD4 knockdown decreased cell apoptosis in MI mice model. Subsequently, mechanism experiments revealed that microRNA-200a-3p (miR-200a-3p) could bind to either MALATA1 or PDCD4. Combining with the cytoplasmic location of MALAT1, we confirmed that MALAT1 acted as a competing endogenous RNA (ceRNA) to upregulate PDCD4 by sponging miR-200a-3p. Finally, rescue assay suggested that MALAT1-miR-200a-3p-PDCD4 axis regulated the proliferation, cell cycle progression and apoptosis of hypoxia-induced myocardial cells.

The spatial patterns, ecological risks, and sources of heavy metals (HMs), including Pb, Zn, Mn, Cu, Cd, Hg, and As in river sediments, were identified around a lead-zinc mine of Danzhai, Guizhou, China. The concentrations of selected HMs and their coefficient variations indicated that the river sediments around this typical lead-zinc mine were obviously contaminated with HMs. Anthropogenic activities had further enhanced the accumulation of HMs. The higher contents of the most common selected HMs were mainly distributed in the area close to the lead-zinc mine. Based on the combined evaluations of the single factor pollution index, geo-accumulation index, and potential ecological risk index, it indicated that the ecological risks of Hg, Cd, Zn, and Pb were high or extremely high, and of Mn, Cu, and As were slight or none in the sediments around this lead-zinc mine. It was found that lead-zinc mining and smelting activities, coal mining activities, and agricultural activities (livestock and poultry breeding) are the primary sources of selected HMs, based on the results of correlation analysis together with principal component analysis (PCA) and positive matrix factorization (PMF) model. The pollution of HMs in the river sediments around a lead-zinc mine was predominantly caused by lead-zinc mining and smelting activities. Therefore, for environmental persistence, lead-zinc mining and smelting activities should be given careful consideration and under close surveillance.

The feasibility of utilizing discrete excitation-emission spectra (DEEMs) to identify dominant groups of phytoplankton at both the genus and division levels was investigated. First, the characteristics of in vivo DEEMs were extracted using Coif2 wavelet. Second, optimal characteristic spectra of scale vectors (SOCS) and time-series vectors (TOCS) were selected by Fisher linear discriminant analysis (FLDA). Third, the SOCS and TOCS were sorted using hierarchical cluster analysis (HCA), and a two-rank database was established according to their discrimination ability. Fourth, the discrimination of phytoplankton was established by nonnegative least squares (NNLS). For single-species samples, the correct identification ratios (CIRs) were 62.9%–100% at the genus level and 95.1%–100% at the division level. The dominant species in the mixtures had corresponding CIRs of 87.5% and 97.9%, and 23 dominant species were correctly identified. Prorocentrum donghaiense D. Lu, Thalassiosira nordenskioeldi Cleve, Chaetoceros socialis Lauder (bloom-forming species with a density of about 107 cell·L−1), and Skeletonema costatum (Grev.) Cleve (a dominant species with a density of 104–106 cell·L−1 in seawater) were identified at the genus level. Other dominant species in seawater were identified at the division level if their density was 105–106 cell·L−1. [ABSTRACT FROM AUTHOR]