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1.
The aquatic plant, Canna indica L. (Indian shoot) of Cannaceae family was investigated to assess cadmium scavenging potential at 5, 10, 25, 50, 100 and 150 mg Cd L?1 exposers. The results showed that Canna has considerable potential of cadmium accumulation, which was up to 58.69 and 10.13 mg Cd kg?1 dry weight in root and shoot of Canna, respectively. The effects of different cadmium levels on biomass production of plant tissues were significantly (p?=?0.05) showed negative relation due to cadmium toxicity. The root concentration factor was higher than the bioconcentration factor which indicated the lower translocation factor of Canna. Considering the high root concentration factor, average bioconcentration factor, rapid growth and optimum adaptive properties up to 100 mg Cd L?1 level, the Canna could be employed as an eco-friendly and efficient aquatic plant for cadmium scavenging. This study plays a potential role in remediation of cadmium contaminated wastewater.  相似文献   

2.
Grazing by cladocerans can reduce the survival of enteric bacteria associated with fecal pollution. This study examined the potential of Daphnia magna to filter commensal and pathogenic Escherichia coli of human origin. Grazing on commensal and pathogenic bacteria was comparable, but slightly greater at 20 compared to 15 and 25°C. Filtering activity was strongly dependent on D. magna and E. coli densities at environmentally relevant bacterial concentrations. Maximum feeding rates were >107 cells h?1 daphnid?1, clearance rates were 1–6 mL h?1 daphnid?1, and filtering was independent of bacterial cell sizes between 0.7 and 1.8 µm. Filtering and ingestion of E. coli by D. magna was susceptible to acute inhibition by unionized ammonia with a 24 h EC50 of 0.18 mg L?1 NH3–N, and a LOEC of 0.09 mg L?1 NH3–N. The study indicated that biological and chemical constraints should be considered when applying Daphnia for attenuation of fecal pollution.  相似文献   

3.
The toxicity of chlortetracycline (CTC), oxytetracycline (OTC) and enrofloxacin (ENF) was tested on two green algal species: the international standard Pseudokirchneriella subcapitata and the native Argentine species Ankistrodesmus fusiformis. All three antibiotics inhibited the algal growth. The most sensitive species was P. subcapitata, for which the EC50 for CTC, OTC and ENF were 1.19?±?0.53, 0.92?±?0.30 and 5.18?±?3.80 mg L?1, respectively. The EC50 for A. fusiformis, were 3.23?±?0.53, 7.15?±?2.69 and 10.6?±?1.28 mg L?1, respectively. The genotoxicity of these veterinary antibiotics was also assessed using chromosome aberration (CA) and micronuclei (MN) induction in Allium cepa roots. Three concentrations were tested (0.1, 1 and 10 mg L?1). Only ENF at 1 and 10 mg L?1 showed any significant MN induction. These data revealed that CTC, OTC and ENF could cause toxicity on green algae, whereas ENF could cause genotoxicity on A. cepa plants.  相似文献   

4.
This study investigated the use of Dracontomelon duperreanum leaf litter extract (DDLLE) in inhibiting the growth and photosynthesis of the algae Microcystis aeruginosa. The goal of the study was to evaluate a potential solution for cyanobacterial bloom prevention. M. aeruginosa was exposed to extract concentrations from 0.4 to 2.0 g L?1. Chlorophyll-a (Chl-a) content and photosynthesis levels were assessed using pulse amplitude modulated fluorimetry phytoplankton analyzer. Results suggested that the extract could efficiently suppress M. aeruginosa growth. The content of Chl-a was only 19.0 µg L?1 and achieved 96.0% inhibition rate when exposed to 2.0 g L?1 on day 15. Growth rate in response to different extract concentrations were consistent with changes in the photosynthesis efficiency (alpha), maximal relative electron transport rate and maximal photochemical efficiency of photosystem II (F v /F m ). Furthermore, several kinds of volatile chemicals and their concentrations in DDLLE had been identified by GC–MS, which of them play major role to suppress the growth of M. aeruginosa should be further studied.  相似文献   

5.
The goal of this study was to assess the rate of urea nitrogen uptake (ρ) by Oocystis borgei and the relationship between environmental factors and ρ. Light intensity, temperature, pH, salinity, and algal concentration, were used to construct an empirical model. The results showed that light intensity, algal concentration, pH and salinity had significant effects on ρ, and the optimal combination of environmental conditions for ρ was a temperature of 25°C, pH of 7.0, light intensity of 81 µmol m?2 s?1, salinity of 15‰, and algal concentration of 4.5?×?108 cell L?1–5.5?×?108 cell L?1. The model equation was ρ?=?2?×?10?5?×?(A0.363B0.783C0.045D?0.503E)?+?0.0017, with a coefficient of determination (R2) of 0.83. No significant difference in variance was observed between the model-predicted values and the measured values (F?=?0.238, p?>?0.05), which demonstrated the high fitting degree of the simulation equation. This study provided valuable insight into the reduction of urea nitrogen levels in aquaculture water by O. borgei.  相似文献   

6.
This study determined the effects of nitrite on different life stages of the Amazon river prawn Macrobrachium amazonicum. Prawns of each life stage (postlarvae, juveniles and adults) were stocked in 24 experimental units (n?=?10 prawns), under a complete randomized design. Individuals were exposed to nitrite (0, 1, 2, 4, 8 and 16 mg L?1). The median lethal concentration after 96 h (96 h LC50) was calculated through the Weibull I. The mortality results showed that M. amazonicum is slightly less tolerant to nitrite than other species of Macrobrachium. The 96 h LC50 for postlarvae, juveniles and adults of M. amazonicum were of 1.49, 2.36 and 2.34 mg nitrite/L, respectively. Nitrite intoxication risk quotient suggest moderated risk to low risk to the species. Usually in production systems nitrite values are lower than safe levels suggested in this study (0.1 mg L?1 to postlarvae and 0.2 mg L?1 nitrite to juvenile and adults), which makes our results appropriate for the production of this species.  相似文献   

7.
Musk ambrette (4-tert-butyl-3-methoxy-2,6-dinitrotoluene) is a nitro musk, a cheap substitute for natural musk and a potential environmental pollutant based on its persistence, accumulation in human organisms. We investigated the acute toxicity of musk ambrette using wild-type AB and transgenic Tg(fli1a:EGFP)y1 zebrafish. Different concentrations were delivered to zebrafish by direct soaking from 6 to 72 h post-fertilization (hpf). The LC50 of musk ambrette was 76.4 µg mL?1. As musk ambrette concentration increased, zebrafish embryos showed developmental delays (50 µg mL?1, 22 hpf), pericardial edema (5 µg mL?1, 48 hpf), circulatory disturbances, curved body axis (1 µg mL?1, 72 hpf) and death (100 µg mL?1, 22 hpf). Target organ toxicity was evaluated by a zebrafish angiogenesis model. Musk ambrette induced cardiovascular morphological changes, vessel permeability variation, angiogenic changes and cardiotoxicity (10 µg mL?1, 48 hpf). The disappearance of caudal vein plexus confirmed the vascular development toxicity. Musk ambrette negatively affects early life-stage survival and demonstrates various toxicities in zebrafish.  相似文献   

8.
In agricultural catchments, aquatic ecosystems can experience a pulse exposure to pesticides. Following such exposure, non-target organisms that are not extirpated may recover. This paper investigates the potential of two duckweed species (Lemna minor and Lemna gibba) to recover from a 7-day exposure to different concentrations (0.4–208 µg L?1) of the herbicide diuron. There was significant inhibition in the growth and biomass after the initial 7-day exposure (e.g. frond number EC50 = 59.2 and 52.2 µg L?1 for L. minor and L. gibba, respectively). Following transfer to clean media, recovery (the highest concentration yielding no significant difference in the effect endpoint from the control) was observed for all effects endpoints at concentrations ranging 60–111 µg L?1 for L. minor and 60–208 µg L?1 for L. gibba. These results suggest that recovery is possible for primary producers at environmentally relevant concentrations considered significant in ecological risk assessment.  相似文献   

9.
Dalbergia sissoo DC, a leguminous tropical timber tree has been investigated against the Pb toxicity; under the Pb-stress, plant’s morphology, biochemical parameters and genomic template stability (GTS) screened in vitro. At the optimum Pb tolerance level (150 mg L?1), plant’s defense mechanism—superoxide dismutase, catalase, ascorbate peroxidases and proline could trigger to achieve optimum vegetative growth with minimum fluctuations of the GTS. Further, D. sissoo roots could accumulate 2399.8?±?16 mg kg?1 Pb. Scanning electron microscopy and energy dispersive X-ray spectrometer analysis also revealed the deposition of Pb in root tissues. In a 1 year pot experiment with Pb-contaminated soil, the plants exhibited normal growth, and Pb accumulation significantly enhanced by the amalgamation of citric acid in the soil. Thus, the tree may prove as a potential candidate for Pb phytostabilization.  相似文献   

10.
To evaluate the removal of potassium cyanide (KCN) and its toxicity in algae, an initial comprehensive analysis was performed with Chlorella vulgaris. The algae showed potential removal capability for KCN, with the maximal removal rate of 61%. Moreover, effects of KCN on growth, cellular morphology and antioxidant defense system of C. vulgaris were evaluated. Cell number and chlorophyll a content decreased in most cases, with the maximal inhibition rates of 48% and 99%, respectively. The 100 mg L??1 KCN seriously damaged the algal cell membrane. Additionally, activity of superoxide dismutase (SOD) was promoted by KCN exposure among 0.1–50 mg L??1 and inhibited by 100 mg L??1 KCN, while the malondialdehyde (MDA) content gradually decreased in C. vulgaris with increasing exposure concentration compared to the control. The present study reveals that C. vulgaris is useful in bio-treatment of cyanide-contaminated aquatic ecosystem, except in high concentrations which would cause overwhelming effects.  相似文献   

11.
The effects of water pH on life history parameters of Bosmina tripurae have been studied to determine the most suitable water pH desired for the maximum growth and development of this newly discovered cladoceran species. The study was carried out under the laboratory condition at 20?±?2°C. Five pH ranges 5.0?±?0.2, 6.0?±?0.2, 7.0?±?0.2, 8.0?±?0.2 and 9.0?±?0.2 with six replicates for each pH consisting of one animal in each Petri dish (80?×?15 mm) were used for the study. 20 mL of respective test medium was maintained with Chlorella sp. (2?×?104?±?0.03 cells mL?1) in each Petri dish throughout the experiment. Thirty (30) animals were observed daily to investigate different life history parameters like total life span, age at maturity, number of eggs, neonates and egg batches etc. at different condition. From the study it was found that acidic water (pH 5?±?0.2) is more suitable for the culture of Bosmina tripurae in laboratory condition.  相似文献   

12.
This study evaluated the effect of inoculation with a mixture of spores of arbuscular mycorrhizal fungi (AMF) (Glomus macrocarpum, Paraglomus occultum, and Glomus sp.) on the initial establishment of Acacia mangium, Sorghum bicolor, and Urochloa brizantha in soil contaminated with heavy metals. The experiment was conducted in a greenhouse, in plastic pots containing 1.8 kg of soil, which presented 7200, 1140, 480, and 72 mg of Zn, Cu, Pb, and Cd, respectively. The chlorophyll content (SPAD index) of inoculated plants of A. mangium and U. brizantha was higher than those of non-inoculated plants (p?<?0.05). No differences were detected for the concentration of heavy metals in plant shoots, whether the plant was inoculated or not. However, inoculated plants had greater root length (S. bicolor and U. brizantha) (p?<?0.05) and greater plant height (A. mangium) (p?<?0.05). The present results demonstrate that the beneficial effects of AMF on plant growth and the alleviation of contaminants are imperative factors for the rehabilitation of soils contaminated with heavy metals.  相似文献   

13.
The present study evaluates potential toxic effects of bis(2-ethylhexyl) adipate (DEHA) plasticizer to larval (72 h post fertilization) zebrafish (Danio rerio) by analyzing changes in expression levels of stress-related genes (p53, rad51 and xrcc5) and assessing possible DNA damage of DEHA in larvae. The lethal concentration for 50% mortality (LC50) in larval zebrafish exposed for 96 h to 0–200 mg L?1 DEHA was 89.9?±?8.03 mg L?1. A concentration-dependent increase in DNA strand breaks was detected in cells from larvae exposed for 96 h to DEHA. There were some significant differences in induction of stress-related genes in larvae exposed to DEHA relative to control.  相似文献   

14.

Backgrounds

Recent experiments suggest that Citrus bergamia extracts could benefit people with dyslipidemia and obesity but this needs to be further validated.

Methods

A total of 98 people age-matched older adults (65 years) with elevated blood lipids were enrolled to receive 12-week supplementation of a Citrus bergamia extracts-based formulation (CitriCholess)(n?=?48) and placebo (n?=?50).

Results

No group differences were found in baseline bodyweight, body mass index (BMI), blood cholesterol (TC), triglycerides (TG), low density lipoprotein cholesterol (LDL-C) and glucose levels. CitriCholess supplementation resulted in lower levels than placebo in TG (1.83?±?0.92 vs. 1.95?±?1.34 mmol/L, P?=?0.612), TC (5.14?±?0.98 vs. 5.44?±?0.77 mmol/L, P?=?0.097), and LDL-C (3.13?±?0.74 vs. 3.43?±?0.62 mmol/L, P?=?0.032). Compared to placebo, CitriCholess also resulted in greater reductions in body weight (?0.604?±?0.939 vs. 0.06?±?0.74 kg, P?<?0.01), waist circumferences (?0.60?±?1.349 cm vs. -0.16?±?1.503 cm, P?<?0.01) and BMI (?0.207?±?0.357 vs. 0.025?±?0.274, P?<?0.01). Additionally, females had a significantly higher level of HDL-C than males. TC was significantly correlated with LDL-C, and to a less degree, with TG. TG was inversely correlated with HDL-C. Body weight and waist circumference were negatively correlated with HDL-C and positively correlated with glucose.

Conclusion

12-week supplementation of CitriCholess could benefit lipid metabolism and weight management in old adults with dyslipidemia.
  相似文献   

15.
Objective To compare the Danish Physical Activity Questionnaire (DPAQ) estimating physical activity energy expenditure (PAEE) and physical activity level (PAL) and the pattern of physical activity (including health-related physical activity) with measurements from a validated position and motion instrument (ActiReg®). Methods One hundred and thirty-eight healthy Danish volunteers aged 20–59 years participated. Participants filled in the DPAQ at the end of the day every day for seven consecutive days and carried the ActiReg® on the same days as the DPAQ were filled in. Results A small, but statistically significant difference was seen between the DPAQ and the ActiReg® for PAEE (mean: ?0.32 MJ·d?1; 95% limits of agreement: ((?2.88)–2.24 MJ·d?1); = 0.003) and PAL (?0.03; ((?0.37)–0.31); = 0.02) for the whole group and for women (< 0.008 for PAEE and PAL), but not for men. The correlation between methods was good for PAEE (= 0.71, < 0.001) and PAL (= 0.64, < 0.001). No difference was observed for time spent in moderate plus vigorous physical activity (MVPA) (= 0.40). Time reported in MVPA with the DPAQ was positively correlated with time spent in MVPA measured by the ActiReg® (ρ = 0.53, < 0.001). Conclusions Although the volunteer sample may influence the representativeness of the results, the DPAQ provided a close estimate of PAEE, PAL (2–5% underestimation) and health-related physical activity (MVPA) in healthy adults at group level. The results indicate that the questionnaire can be used to rank individuals according to energy expenditure and level of total physical activity and to provide information on health-related physical activity.  相似文献   

16.

Purpose

This study aimed (1) to examine the role of potential correlates of HRQoL in a large representative sample of older adults, and (2) to investigate whether the relationships between HRQoL and potential factors differ as a function of HRQoL component (physical vs. mental) and/or age cohort (young-old vs. old–old).

Methods

This cross-sectional study included 802 older adults aged 60–79 years old. HRQoL was assessed using the SF-36 questionnaire. Functional fitness was assessed using the Senior Fitness Test. Physical activity was measured via the Baecke questionnaire. Demographic information, mental and health features were obtained through questionnaires.

Results

A multiple regression analysis showed that BMI (β = ?0.15, p?=?0.001), body strength (β =?0.21, p?<?0.001), aerobic endurance (β =?0.29, p?<?0.001), physical activity (β =?0.11, p?=?0.007), depressive symptoms (β = ?0.19, p?<?0.001), falls (β = ?0.19, p?<?0.001), and living alone (β = ?0.16, p?<?0.001) were all significantly related to HRQoL-SF-36 total score. The positive relation with aerobic endurance was significantly higher for the physical component of HRQoL, while the negative relation with living alone was significantly higher for the mental component. The positive relation of HRQoL with physical activity was significantly higher in old–old compared to young-old adults.

Conclusion

This data suggest that body composition, functional fitness, psycho-social factors, and falls are important correlates of HRQoL in old age. There are HRQoL-component and age-cohort differences regarding these correlates, underlying the need for specific strategies at the community level to promote HRQoL in older adults.
  相似文献   

17.
To investigate the biomagnification factor (BMF) of EDCs by the polychaete, Perinereis nuntia, organisms were exposed to EDCs through their diet. BMF values ranged from 0.001 to 0.028 indicating that EDCs were not biomagnified. Elimination rates were (0.20–0.25 day?1) and were higher than uptake rate (0.0003–0.003 day?1) verifying that EDCs were not biomagnified by P. nuntia due to their fast elimination. The calculated half-life of each EDC in this study varies from 2.76 to 3.45 days. Overall, the findings from this study demonstrated that the studied EDCs are not biomagnified in P. nuntia but exposure does occur from the diet.  相似文献   

18.

Aims

We evaluated pedometry as a novel patient-centered outcome because it enables passive continuous assessment of activity and may provide information about the consequences of symptomatic toxicity complementary to self-report.

Methods

Adult patients undergoing hematopoietic cell transplant (HCT) wore pedometers and completed PRO assessments during transplant hospitalization (4 weeks) and 4 weeks post-discharge. Patient reports of symptomatic treatment toxicities (single items from PRO-CTCAE, http://healthcaredelivery.cancer.gov/pro-ctcae) and symptoms, physical health, mental health, and quality of life (PROMIS® Global-10, http://nih.promis.org), assessed weekly with 7-day recall on Likert scales, were compared individually with pedometry data, summarized as average daily steps per week, using linear mixed models.

Results

Thirty-two patients [mean age 55 (SD = 14), 63 % male, 84 % white, 56 % autologous, 43 % allogeneic] completed a mean 4.6 (SD = 1.5, range 1–8) evaluable assessments. Regression model coefficients (β) indicated within-person decrements in average daily steps were associated with increases in pain (β = ?852; 852 fewer steps per unit increase in pain score, p < 0.001), fatigue (β = ?886, p < 0.001), vomiting (β = ?518, p < 0.01), shaking/chills (β = ?587, p < 0.01), diarrhea (β = ?719, p < 0.001), shortness of breath (β = ?1018, p < 0.05), reduction in carrying out social activities (β = 705, p < 0.01) or physical activities (β = 618, p < 0.01), and global physical health (β = 101, p < 0.001), but not global mental health or quality of life.

Conclusions

In this small sample of HCT recipients, more severe symptoms, impaired physical health, and restrictions in the performance of usual daily activities were associated with statistically significant decrements in objectively measured daily steps. Pedometry may be a valuable outcome measure and validation anchor in clinical research.
  相似文献   

19.
20.

Objective

To examine the association between food and beverage consumption and time spent in different sedentary behaviours such as watching TV and DVDs, playing computer/video games and quiet play/activities in preschoolers.

Methods

A sample of 6431 (51.8 % males) European preschoolers aged 3.5–5.5 years from six survey centres was included in the data analyses. Data on dietary habits and sedentary behaviours [watching TV, playing computer and quiet play (both during weekdays and weekend days)] were collected via standardized proxy-administered questionnaires. One-way analysis of covariance and general linear model (adjusted for sex, maternal education, body mass index and centre) were conducted.

Results

The results of the generalized linear model showed that the more strong associations in both males and females who were watching TV for > 1 h/day during weekdays were positively associated with increased consumption of fizzy drinks (β = 0.136 for males and β = 0.156 for females), fresh and packed juices (β = 0.069, β = 0.089), sweetened milk (β = 0.119, β = 0.078), cakes and biscuits (β = 0.116, β = 0.145), chocolate (β = 0.052, β = 0.090), sugar-based desserts and pastries (β = 0.234, β = 0.250), salty snacks (β = 0.067, β = 0.056), meat/poultry/processed meat (β = 0.067, β = 0.090) and potatoes (β = 0.071, β = 0.067), and negative associations were observed for the consumption of fruits (β = ?0.057, β = ?0.099), vegetables (β = ?0.056, β = ?0.082) and fish (β = ?0.013, β = ?0.013). During weekend days, results were comparable.

Conclusions

In European preschoolers, sedentary behaviours were associated with consumption of energy-dense foods and fizzy drinks. The present findings will contribute to improve the strategies to prevent overweight, obesity and nutrition-related chronic diseases from early childhood.
  相似文献   

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