Co-occurrence of multiple cyanotoxins and taste-and-odor compounds in the large eutrophic Lake Taihu, China: Dynamics, driving factors, and challenges for risk assessment.

Cyanobacterial blooms producing toxic metabolites occur frequently in freshwater, yet the environmental behaviors of complex cyanobacterial metabolites remain largely unknown. In this study, the seasonal and spatial variations of several classes of cyanotoxins (microcystins, cylindrospermopsins, saxitoxins) and taste-and-odor (T&O) compounds (ß-cyclocitral, ß-ionone, geosmin, 2-methylisoborneol) in Lake Taihu were simultaneously investigated for the first time. The total cyanotoxins were dominated by microcystins with concentrations highest in November (mean 2209 ng/L) and lowest in February (mean 48.7 ng/L). Cylindrospermopsins were abundant in May with the highest content of 622.8 ng/L. Saxitoxins only occurred in May (mean 19.2 ng/L) and November (mean 198.5 ng/L). Extracellular T&O compounds were most concentrated in August, the highest being extracellular ß-cyclocitral (mean 240.6 ng/L) followed by 2-methylisoborneol (mean 146.6 ng/L). Environment variables play conflicting roles in modulating the dynamics of different groups of cyanotoxins and T&O compounds. Total phosphorus (TP), total nitrogen (TN), chlorophyll-a and cyanobacteria density were important factors affecting the variation of total microcystins, ß-cyclocitral and ß-ionone concentrations. In contrast, total cylindrospermopsins, 2-methylisoborneol and geosmin concentrations were significantly influenced by water temperature and TP. There was a significant and linear relationship between microcystins and ß-cyclocitral/ß-ionone, while cylindrospermopsins were positively correlated with 2-methylisoborneol and geosmin. The perceptible odors may be good indicators for the existence of cyanotoxins. Hazard quotients revealed that potential human health risks from microcystins were high in August and November. Meanwhile, the risks from cylindrospermopsins were at moderate levels. Cylindrospermopsins and saxitoxins were first identified in this lake, suggesting that diverse cyanotoxins might co-occur more commonly than previously thought. Hence, the risks from other cyanotoxins beyond microcystins shouldn't be ignored. This study also highlights that the necessity for further assessing the combination effects of these complex metabolites.

A novel assessment and forecasting system for traffic accident economic loss caused by air pollution.

Air pollution greatly reduces the visibility of the air, leading to frequent traffic accidents (TA), and the resulting economic losses cannot be ignored. In order to better control and mitigate the traffic accident economic losses of air pollution, this paper proposes a novel assessment and forecasting system for TA economic loss of air pollution, which contains assessment module and forecasting module. In the assessment module, a reasonable assessment of TA economic loss is provided which also analyzes the efficiency of air pollution control based on data envelope analysis directional distance function. In the forecasting module, this system develops a rolling nonlinear optimized initial self-adapting grey model based on multi-objective optimization algorithm to forecast the TA economic loss of air pollution. The results from the proposed system indicate that the proposed system has outstanding performance which can provide great information assistant for a decision-maker.

Comparative toxicological effects of planktonic Microcystis and benthic Oscillatoria on zebrafish embryonic development: Implications for cyanobacteria risk assessment.

Planktonic and benthic cyanobacteria blooms are increasing in frequency in recent years. Although many studies have focused on the effects of purified toxins or cyanobacteria extracts on fish developments, the more complex impacts of cyanobacteria cells on fish populations are still considered insufficient. This study compared the toxicological effects of harmful planktonic Microcystis and benthic Oscillatoria on zebrafish (Danio rerio) early stages of development. Zebrafish embryos, at 1-2 h post fertilization (hpf), were exposed to 5, 10, and 20 × 105 cells/mL Microcystis (producing microcystins) or Oscillatoria (producing cylindrospermopsins) until 96 hpf. The results indicated that the effects of benthic Oscillatoria on embryonic development of zebrafish were different from those of planktonic Microcystis. Reduced hatching rates, increased mortality, depressed heart rates and elevated malformation rates were observed following exposures to increased concentrations of Microcystis, whilst Oscillatoria exposures only caused yolk sac edemas. Exposure to a high concentration of Microcystis induced severe oxidative damage, growth inhibition and transcriptional downregulations of genes (GH, GHR1, IGF1, IGF1rb) associated with the growth hormone/insulin-like growth factor (GH/IGF) axis. Although Oscillatoria exposure did not affect the body growth, it obviously enhanced the antioxidant enzyme activities of superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPx) and up-regulated the expressions of several oxidative stress-related genes. Discrepancies in the developmental toxicity caused by Microcystis and Oscillatoria may not only attributed to the different secondary metabolites they secrete, but also to the different adhesion behaviors of algal cells on embryonic chorion. These results suggested that harmful cyanobacteria cells could influence the successful recruitment of fish, while the effects of benthic cyanobacteria should not be ignored. It also highlighted that the necessity for further investigating the ecotoxicity of intact cyanobacterial samples when assessing the risk of cyanobacterial blooms.

[Distribution and Risk Assessment of OCPs in Surface Water, Sediments, and Fish from Lake Gucheng and Inflow and Outflow Rivers].

To investigate the distribution, source, and ecological risk of organochlorine pesticides (OCPs) residues in Lake Gucheng, surface water, sediment, and biological samples were collected from 12 sampling sites of Lake Gucheng and its inlets and outlets during summer and winter, and the concentrations of 19 OCPs were analyzed. The results showed that the concentration (dry weight) of OCPs in Lake Gucheng ranged from 26.74 to 48.12 ng·L-1 in surface water, 9.01 to 35.34 ng·g-1 in sediment, and 13.39 to 124.29 ng·g-1 in organisms. The pollution characteristics of OCPs in surface water showed that the concentration was much higher in summer than in winter, and much higher at inflow and outflow rivers than in farming ponds and the central region of Lake Gucheng; the seasonal pollution characteristics in sediment were not obvious. All 19 kinds of OCPs in water, sediment, and organisms were detected in different degrees, and the dominant contaminants were HCHs and DDTs. α-HCH was the main pollutant at all sites in both surface water and sediment, with 21% to 42% of total HCHs in two seasons. p,p'-DDD was the main pollutant in surface water with 30% to 76% of total DDTs, whereas p,p'-DDT was the main pollutant in sediment with 68% to 93% of total DDTs in two seasons. Source analysis based on ratios of HCHs isomers and DDTs isomers indicated that there was a new input of OCPs under anaerobic conditions in the study area. The ecological risk assessment showed that the OCPs in surface water did not lead to significant health risks, but the OCPs in sediments might pose ecological risks to the Lake Gucheng ecosystem. The organisms were within the acceptable potential carcinogenic risk range.

Health-Related Internet Use in Hard-to-Reach Populations: Empirical Findings From a Survey in a Remote and Mountainous Province in China.

BACKGROUND: The expanding use of the internet contributes to more effective searches for health-related information and opens up opportunities for direct Web-based communication with health care professionals. However, little is known about how users' characteristics on the demand side influence health-related internet use, especially in remote and rural areas within developing countries. The absence of accurate estimates of users' characteristics and their impact on adaptations of health care services in developing countries constrains focused policy-centered discussions and the design of appropriate policies. OBJECTIVE: The aim of this study was to assess the prevalence of health-related internet use and to identify its determinants in a remote province in China. METHODS: We conducted a cross-sectional survey in June and July of 2018 in Ningxia, located in northwestern China. Rural households were selected by multistage random sampling, and households' key members were interviewed face-to-face at the respondents' home. Dependent variables were whether the households use Web health services or not. Independent variables were chosen based on the Andersen behavioral model. Sociodemographic characteristics were compared between households that used health-related Web services with nonusers. We applied logistic regression models to evaluate multivariate associations between respondents' characteristics and their usage of Web-based health services and obtained odds ratios with 95% CI. RESULTS: A total of 1354 respondents from rural households were interviewed, of whom 707 (52.22%) were men. The mean age of the respondents was 44.54 years (SD 10.22). Almost half of the surveyed households (640/1354, 47.27%) reported using 1 or more Web-based health care services, whereas 37.8% (502/1354) reported using the internet to obtain health-related information, 15.51% (210/1354) used the internet to communicate with professionals about health issues, and 7.24% (98/1354) had engaged in Web-based consultations in the last year. After controlling for potential confounders, households engaged in health-related internet use were found to be wealthier, have higher health demands, and have less geographic access to high-quality health care compared with other households. CONCLUSIONS: The internet has become a major health information resource in rural Ningxia. Social structures, family enabling factors, health needs, and characteristics relating to health care access were significant predictors of households' health-related internet use in rural and remote areas in China. Those who belong to older age groups, have low income, and whose education levels do not extend beyond primary school education are significantly less likely to use Web-based health care services and to benefit from Web-based health care programs. A need for continued collaborative efforts involving multiple stakeholders, including communities, Web-based and other health care providers, family members, and the government is needed.

Trends in health resource disparities in primary health care institutions in Liaoning Province in Northeast China.

BACKGROUND: The allocation of health resources in primary health care institutions (PHCI) is crucial to health reform. China has recently implemented many reform measures emphasizing the provision of primary health care services, with equity as one of the major goals. The aim of this study was to analyze the quantity, quality, and distribution of health resources in Liaoning Province from 2005 to 2017. METHODS: Data were drawn from the annual financial report from 2005 to 2017 and information from the Liaoning Province Department of Statistics. Numbers of beds and physicians were used as indicators of health resources. Capital assets per bed, value of medical equipment per bed, operational space per bed, and number of physicians with different educational levels were used as indicators of quality of health resources. Concentration indices (CI) and Gini coefficients were calculated. RESULTS: There was a steady rise in health resources in PHCI. From 2005 to 2017, the quality of health resources improved. The CI of beds showed an overall downward trend, indicating an improvement in the disparity among PHCI. There was a similar trend in the CI of fixed assets per bed. The Gini coefficients of physicians overall and physicians with different educational levels were almost always < 0.3, showing preferred equity status. There was a decreasing trend in the Gini coefficients of PHCI physicians with bachelor's degrees or higher and physicians with associate's degrees. The proportion of health resource of PHCI in health system increased from 2005 to 2009, before decreasing from 2009 to 2017 and the percentage of physicians overall and physicians with bachelor's degrees or higher in PHCI declined after 2011. CONCLUSIONS: There was an improvement in the quantity and quality of health resources in PHCI from 2005 to 2017. The distribution of health resource allocation in PHCI also improved. The findings revealed that the measures for the improvement of PHCI physicians' educational level has been successful and the measures taken by the government in health reform to strengthen the primary health care system have not been successful.

Very-Low-Dose Decitabine Is Effective in Treating Intermediate- or High-Risk Myelodysplastic Syndrome.

Nowadays, the regular recommended dose of decitabine for the treatment of myelodysplastic syndrome (MDS) is 20 mg/m2/day for 5 consecutive days with a relatively high incidence of treatment-related morbidities and costs. In this study, a retrospective and multicenter analysis was performed to explore the very-low-dose decitabine schedule for the treatment of patients with IPSS intermediate- or high-risk MDS. A total of 31 newly diagnosed MDS cases from 14 hospitals in Beijing received decitabine monotherapy (decitabine 6 mg/m2/day intravenously for 7 consecutive days, repeated every 4 weeks). With a medium follow-up of 4 months, 10 patients achieved complete remission (32.3%), 8 (25.8%) partial remission, and 3 (9.7%) hematological improvement. The overall response rate (ORR) was 67.7%. Rates of 21.7% for severe infections and 11.6% for severe bleedings were observed among all courses. The median cost of each course was USD 5,300, 3,000, 2,900, and 2,000, respectively. Multivariate analysis identified bone marrow blast cells ≥10% and a Charlson comorbidity index ≥1 as 2 independent factors for efficacy. In conclusion, very-low-dose decitabine showed relatively good efficacy, good tolerance, and low medical cost in the treatment of intermediate- or high-risk MDS. Elderly patients with more than 1 complication or patients with a higher proportion of blast cells may be the most suitable candidates for this regimen.

Modulation, bioinformatic screening, and assessment of small molecular peptides targeting the vascular endothelial growth factor receptor.

Vascular endothelial growth factor (VEGF) and VEGF receptor (VEGFR) are important factors in tumor growth and metastasis. Molecular probes or drugs designed to target VEGF/VEGFR interactions are crucial in tumor molecular imaging and targeted therapy. Bioinformatic methods enable molecular design based on the structure of bio-macromolecules and their interactions. This study was aimed to identify tumor-targeting small-molecule peptides with high affinity for VEGFR using bioinformatics screening. The VEGFR extracellular immunoglobulin-like modules Ig1-Ig3 were used as the target to systematically alter the primary peptide sequence of VEGF125-136. Molecular docking and surface functional group interaction methods were combined in an in silico screen for polypeptides, which in theory, would have higher affinities for VEGFR. In vitro receptor competition binding assays were used to assess the affinity of the putative VEGFR-binding polypeptides. Rhodamine-conjugated peptides were used to label and visualize peptide-binding sites on A549 cells. Using bioinformatic screening, we identified 20 polypeptides with potentially higher affinity for VEGFR. The polypeptides were capable of inhibiting the binding of (125)I-VEGF to VEGFR in a dose-dependent manner. The IC50 values of QKRKRKKSRKKH and RKRKRKKSRYIVLS (80 and 185 nmol/L, respectively) were significantly lower than that of VEGF125-136 (464 nmol/L); thus, the affinity of these peptides for VEGFR was 6- and 2.5-fold higher, respectively, than that of VEGF125-136. Rhodamine labeling of A549 cells revealed peptide binding mainly on the plasma membrane and in the cytoplasm. Bioinformatic approaches hold promise for the development of molecular imaging probes. Using this approach, we designed two peptides that showed higher affinity toward VEGFR. These polypeptides may be used as molecular probes or drugs targeting VEGFR, which can be utilized in molecular imaging and targeted therapy of certain tumors.

Assessment of antibacterial properties and the active ingredient of plant extracts and its effect on the performance of crucian carp (Carassius auratus gibelio var. E'erqisi, Bloch).

BACKGROUND: In this study, the antibacterial properties and active ingredient of plant extracts and its effect on the performance of crucian carp (Carassius auratus gibelio var. E'erqisi, Bloch) were assessed. RESULTS: The transmission electron microscopy and flow cytometric analysis showed that the antibacterial activity of plant extracts is due to the disruption of the cell membrane and the leakage of cytoplasmic contents. The UPLC-MS/MS analysis showed that the contents of gallic acid, (-)-epigallocatechin, (+)-catechin, (-)-epigallocatechin gallate, (-)-epicatechin gallate, aloe-emodin, rhein, emodin, chrysophanol, and physcion, were 5.27%, 3.30%, 1.08%, 19.32%, 5.46%, 0.23%, 0.56%, 1.28%, 0.75% and 0.39% in plant extracts, respectively. Results of feeding experiment showed that feeding crucian carp with 1.0% and 2.0% plant extracts significantly enhanced specific growth rate, serum total protein, lysozyme, catalase and superoxide dismutase activities, and decreased the feed conversion rate, malondialdehyde contents and the mortality rate (P < 0.05). CONCLUSION: It can be concluded that plant extracts added to fish feed can act as natural antimicrobial and immunostimulants to prevent pathogenic infection, enhance immune response, and promote growth of the fish.