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3.
Sci Total Environ ; 894: 164954, 2023 Oct 10.
Article in English | MEDLINE | ID: mdl-37336400

ABSTRACT

This study investigates the leaching potential of several additives embedded in six different plastic types when exposed to extreme simulated marine conditions for 140 days. The findings achieved herein contribute to a better understanding of the impact of macro- and microplastics leaching harmful compounds (bisphenol A (BPA) and phthalates) in the marine environment when exposed to harsh climatic conditions. Leachability experiments showed that bis(2-ethylhexyl) phthalate (DEHP), dibutyl phthalate (DBP), and BPA were detected in seawater (SW) samples. Furthermore, while analysing 100 mL of SW per each sample, the total leachate concentrations of the identified compounds ranged from 5 µg/L to 123 µg/L, after 140 days of exposing a total of 120 plastic samples (96 samples micro- and 24 macro-plastics) to SW conditions It was observed that the leaching of DEHP was promoted by wave abrasion, high temperature and sunlight, while the leaching of DBP was favoured by wave abrasion. Findings showed that polypropylene (PP) was the most attributable plastic type in the leaching of DBP with an average concentration of 5.3 µg/L, whereas high-density polyethylene (HDPE) was the most responsible plastic-type for the leaching of DEHP, with an average concentration of 123 µg/L. Our results suggest that most of the phthalates and BPA will, ultimately, leach out to the SW environment after a longer period.

4.
Interv Neuroradiol ; : 15910199231175375, 2023 May 25.
Article in English | MEDLINE | ID: mdl-37229632

ABSTRACT

BACKGROUND AND PURPOSE: Acute carotid artery stenting (CAS) for ischemic stroke patients with anterior circulation tandem occlusion requires periprocedural antiplatelet therapy to prevent stent thrombosis. However, due to the lack of randomized trials and inconsistent published results, there is no reliable information regarding the safety of additional antiplatelet treatment. Therefore, we compared the safety and functional outcomes of patients treated with acute CAS plus Aspirin during tandem occlusions thrombectomy with isolated intracranial occlusions patients treated with thrombectomy alone. METHODS: Two prospectively acquired mechanical databases from August 2017 to December 2021 were reviewed. Patients were included if they had carotid atherosclerotic tandem occlusions treated with acute CAS and Aspirin (intravenous bolus 250 mg) during thrombectomy. Any antiplatelet agent was added after thrombectomy and before the 24-h control imaging. This group was compared with a matched group of isolated intracranial occlusions treated with thrombectomy alone. RESULTS: A total of 1557 patients were included and 70 (4.5%) had an atherosclerotic tandem occlusion treated with acute CAS plus Aspirin during thrombectomy. In exact coarse matched weight adjusted analysis, the rate of symptomatic intracerebral hemorrhage was similar in both groups (OR, 3.06; 95% CI, 0.66-14.04; P = 0.150), parenchymal hematoma type 2 (OR, 1.15; 95% CI, 0.24-5.39; P = 0.856), any intracerebral hemorrhage (OR, 1.84; 95% CI, 0.75-4.53; P = 0.182), and 90-day mortality (OR, 0.79; 95% CI, 0.24-2.60; P = 0.708). Rates of early neurological improvement and 90-day modified Rankin Scale score 0-2 were comparable. CONCLUSIONS: Acute CAS plus Aspirin during thrombectomy for tandem occlusion stroke appears safe. Randomized trials are warranted to confirm these findings.

5.
Sci Rep ; 13(1): 8014, 2023 05 17.
Article in English | MEDLINE | ID: mdl-37198277

ABSTRACT

Inflammatory processes are increasingly attributed to macrophage polarization. Proinflammatory macrophages promote T helper (Th) 1 response, tissue repair, and Th2 responses. Detection of macrophages in tissue sections is facilitated by CD68. Our study is focused on the expression of CD68 and the estimation of proinflammatory cytokines in children's patients with chronic tonsillitis secondary to vitamin D supplementation. This hospital-based Randomized prospective case-control study was conducted on 80 children with chronic tonsillitis associated with vitamin D deficiency where (40 received vitamin D 50,000 IU weekly for 3-6 months and 40 received 5 ml distilled water as placebo). The serum 25-hydroxyvitamin D [25(OH)D] was measured using an Enzyme-linked immunosorbent assay on all included children. Different histological and immunohistochemical studies for the detection of CD68 were done. There was a significantly lower serum level of 25(OH)D in the placebo group versus the vitamin D group (P < 0.001). The levels of pro-inflammatory cytokines, TNFα, and IL-2 significantly increased in the placebo group as compared to the vitamin D group (P < 0.001). The increased level of IL-4 and IL-10 in the placebo group as compared to the vitamin D group was insignificant (P = 0.32, 0.82) respectively. Vitamin D supplementation alleviated the deleterious effect of chronic tonsillitis on the histological structure of the tonsil. Tonsillar tissues of the children in the control and vitamin D groups demonstrated a highly statistically significantly lower number of CD68 immunoexpressing cells compared with those in the placebo group (P < 0.001). Low vitamin D may play a role in chronic tonsillitis. Vitamin D supplementation could help reduce the occurrence of chronic tonsillitis in susceptible children.


Subject(s)
Tonsillitis , Vitamin D Deficiency , Child , Humans , Case-Control Studies , Cholecalciferol , Cytokines , Dietary Supplements , Vitamin D , Vitamins
6.
Eur J Cardiothorac Surg ; 64(1)2023 07 03.
Article in English | MEDLINE | ID: mdl-37094177

ABSTRACT

OBJECTIVES: Adequate pain management after thoracoscopic surgery is a major issue in the prevention of respiratory complications. The combination of the paravertebral block (PVB) with the serratus anterior plane block (SAPB) may decrease postoperative pain. The objective of this study was to evaluate the impact of the combination of PVB and SAPB on the consumption of morphine and pain after video- or robot-assisted thoracic surgery. METHODS: The main objective of this randomized controlled trial was to compare the cumulative postoperative morphine consumption at 24 h between a group having PVB (PVB group) and a group having PVB and SAPB (PV-SAPB group). Postoperative pain at 6 and 24 h and morphine-related complications were also assessed. RESULTS: A total of 112 patients were included with 56 in each group. There was no difference in median cumulative morphine consumption at 24 h between the 2 groups (P = 0.1640). At 6 h, the median postoperative pain was higher in the PVB group compared to the PV-SAPB group (3 [0; 4] vs 2 [0; 3], P = 0.0231). There were no differences between the 2 groups for pain at 24 h and morphine-related complications. CONCLUSIONS: We did not find any difference in morphine consumption between the 2 groups. Our results suggest that the combination of PVB and SAPB for video-assisted thoracic surgery or robot-assisted thoracic surgery is safe effective and reliable and could be an alternative to PVB alone in certain indications.


Subject(s)
Nerve Block , Thoracic Surgery, Video-Assisted , Humans , Thoracic Surgery, Video-Assisted/adverse effects , Thoracic Surgery, Video-Assisted/methods , Prospective Studies , Nerve Block/adverse effects , Nerve Block/methods , Pain, Postoperative/prevention & control , Pain, Postoperative/etiology , Morphine Derivatives
7.
Mar Pollut Bull ; 189: 114765, 2023 Apr.
Article in English | MEDLINE | ID: mdl-36898272

ABSTRACT

This paper looks at experiential feedback and the technical and scientific challenges tied to the MERITE-HIPPOCAMPE cruise that took place in the Mediterranean Sea in spring 2019. This cruise proposes an innovative approach to investigate the accumulation and transfer of inorganic and organic contaminants within the planktonic food webs. We present detailed information on how the cruise worked, including 1) the cruise track and sampling stations, 2) the overall strategy, based mainly on the collection of plankton, suspended particles and water at the deep chlorophyll maximum, and the separation of these particles and planktonic organisms into various size fractions, as well as the collection of atmospheric deposition, 3) the operations performed and material used at each station, and 4) the sequence of operations and main parameters analysed. The paper also provides the main environmental conditions that were prevailing during the campaign. Lastly, we present the types of articles produced based on work completed by the cruise that are part of this special issue.


Subject(s)
Food Chain , Plankton , Mediterranean Sea , Seasons , Oceanography
8.
Sci Rep ; 13(1): 4209, 2023 Mar 14.
Article in English | MEDLINE | ID: mdl-36918583

ABSTRACT

The present study reports the feasibility of the synthesis of a novel porous composite adsorbent, prepared from olive stone activated carbon (OS400) and garnet (GA) mineral impregnations (referred to as OSMG). This composite (OSMG) was applied for its ability to adsorb a macromolecular organic dye. The composite's structural characteristics were evaluated using various techniques such as Brunauer-Emmett-Teller (BET), Scanning Electron Microscopy equipped with Energy Dispersive X-ray spectroscopy (SEM-EDX), X-ray diffraction (XRD), and a Fourier transform infrared spectrometer (FT-IR). The specific surface area of the garnet (GA), (OS400), and (OSMG) were found to be 5.157 mg⋅g-1, 1489.598 mg⋅g-1, and 546.392 mg⋅g-1, respectively. The specific surface area of the new composite (OSMG) was promoted to enhance the adsorption of methylene blue (MB). Experiments were conducted under various conditions, including contact time, initial dye concentration, adsorbent dosage, pH, and temperatures. Data from these experiments were analyzed using several adsorption models including Langmuir, Freundlich, Temkin, and Dubinin-Radushkevich (D-R). The results indicated that, the adsorption fit best with the Freundlich model and that the adsorption process followed a pseudo-second-order kinetic mechanism. Additionally, the thermodynamic analysis indicated the adsorption of MB onto garnet(GA) adsorbents is endothermic, while the sorption onto (OS400) and (OSMG) is an exothermic and non-spontaneous process. The OSMG composite can be used for at least five cycles without significant loss of adsorptive performance, and can easily be separated from the water after treatment.

9.
J Hazard Mater ; 447: 130796, 2023 Apr 05.
Article in English | MEDLINE | ID: mdl-36669417

ABSTRACT

Plastics possess diverse functional properties that have made them extremely desirable. However, due to poor waste management practices, large quantities eventually end up in the oceans where their degradation begins. Hence, it is imperative to understand and further investigate the dynamics of this process. Currently, most relevant studies have been carried out under benign and/or controlled weather conditions. This study investigates the natural degradation of polypropylene (PP) and polyethylene terephthalate (PET) in more extreme environments. Simulated and real marine conditions, both in the laboratory (indoors) and outdoors were applied for a duration of 140 days and results were assessed using Fourier-transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM) with energy dispersive X-ray analysis. SEM micrographs revealed variations in the morphologies of both plastic types. Degradation signs were shown in both plastic types, under all conditions. Findings indicated that microplastics (MPs) degraded faster than macroplastics, with PP MPs having higher weight loss (49%) than PET MPs (1%) when exposed to outdoor marine conditions. Additionally, the degradation rates of MPs-PP were higher than MPs-PET for outdoor and indoor treatments, with 1.07 × 10-6 g/d and 4.41 × 10-7 g/d, respectively. FTIR combined with PCA was efficient in determining the most degraded plastic types.

10.
Article in English | MEDLINE | ID: mdl-36221874

ABSTRACT

BACKGROUND AND AIM: Chronic kidney disease (CKD) is characterized by persistent lowgrade inflammation. Soluble CD14 (sCD14) is involved in many pathological conditions, including inflammation and atherosclerosis. The present study aimed to assess the relationship between sCD14 levels, subclinical atherosclerosis (SCA), inflammation and mortality in Egyptian hemodialysis (HD) patients. PATIENTS AND METHODS: The present longitudinal study included 62 HD patients. All patients were submitted to careful history taking, thorough clinical examination and laboratory assessment for high-sensitivity C-reactive protein (hsCRP) and sCD14. Carotid intima-media thickness (CIMT) was also assessed. Patients were followed for a maximum of 18 months. The primary outcome is patients' mortality. Data were statistically analyzed using standard descriptive, comparative, correlative and regression methods. RESULTS: The present study was conducted on 62 HD patients. They comprised 34 males and 28 females with an age of 54.6 ± 9.0 years. At the end of follow-up, 12 patients (19.4 %) died. It was shown that survivors had significantly lower hsCRP levels (104.2 ± 38.2 versus 134.1 ± 15.3 mg/dL, p < 0.001), lower sCD14 levels (32.7 ± 10.3 versus 47.4 ± 18.4 µg/mL, p = 0.02) and lower CIMT (1.32 ± 0.5 versus 1.5 ± 0.2 mm, p = 0.049). sCD14 levels were significantly correlated with hsCRP (r = 0.4, p = 0.001) and CIMT (r = 0.31, p = 0.013). Multivariate analysis identified HD duration [HR (95% CI): 1.02 (1.0-1.04), p = 0.021] and sCD14 levels [HR (95% CI): 1.06 (1.0-1.12), p = 0.026] as significant predictors of patients' survival. CONCLUSIONS: sCD14 levels in this cohort of HD patients are well-correlated with hsCRP levels and CIMT. In addition, they are significant predictors of patients' mortality.


Subject(s)
Atherosclerosis , Lipopolysaccharide Receptors , Male , Female , Humans , Middle Aged , C-Reactive Protein/metabolism , Longitudinal Studies , Carotid Intima-Media Thickness , Biomarkers , Inflammation , Renal Dialysis/adverse effects , Atherosclerosis/diagnosis
11.
Cardiovasc J Afr ; 34(2): 93-97, 2023.
Article in English | MEDLINE | ID: mdl-35976685

ABSTRACT

AIM: The aim of this study was to evaluate the association between the left main coronary artery (LM) bifurcation angle and the severity of the proximal left anterior descending coronary artery (LAD) stenosis. METHODS: Two hundred patients with suspected coronary artery disease who had coronary angiography were included in this observational study. The severity of coronary artery stenosis was analysed using quantitative coronary angiography software (QCA analysis). The LM-LAD and LAD-left circumflex artery (LCX) angles were measured using software (IC MEASURE) in two-dimensional axial images. RESULTS: The patients were divided into two groups. The first group included 100 patients with significant proximal LAD stenosis (≥ 50%) and the second, those with LAD stenosis < 50% (100 patients). Patients with significant proximal LAD stenosis were older and had a higher frequency of diabetes mellitus, and higher serum creatinine and low-density lipoprotein levels than those with non-significant LAD stenosis. The LM-LAD and LAD-LCX angles in patients with significant proximal LAD stenosis were wider than in patients with non-significant LAD stenosis (p < 0.001). The cut-off value of 42° of the LM-LAD angle had a sensitivity of 73% and specificity of 70% to predict significant proximal LAD stenosis. The cut-off value of 68° of the LAD-LCX angle had a sensitivity of 68% and specificity of 62% to predict significant proximal LAD disease. In a multivariate logistic regression analysis, LM-LAD and LAD-LCX angles were independent factors for the development of significant proximal LAD stenosis. CONCLUSIONS: Wider LM-LAD and LAD-LCX angles were associated with the severity of proximal LAD disease. Preventative measures and close follow up are needed in such cases to improve their cardiovascular outcome.


Subject(s)
Coronary Artery Disease , Coronary Stenosis , Humans , Coronary Vessels/diagnostic imaging , Constriction, Pathologic , Coronary Artery Disease/diagnostic imaging , Coronary Stenosis/diagnostic imaging , Coronary Angiography/methods
12.
J Cardiovasc Echogr ; 33(3): 133-138, 2023.
Article in English | MEDLINE | ID: mdl-38161778

ABSTRACT

Background: This research aimed to evaluate the role of coronary microvascular dysfunction in alteration of left ventricular (LV) myocardial deformation. Materials and Methods: This observational study involved 50 patients with LV ejection fraction (LVEF) >50% and coronary microvascular dysfunction (diagnosed by coronary angiography). TIMI frame count (TFC) was calculated for each patient. They were classified into 2 groups: 30 patients with heart failure and preserved ejection fraction (HFpEF) (cases group) and 20 patients without HF (control group). Speckle tracking echocardiography was used to evaluate LV deformation. Results: The mean age of the studied patients was 58.8 ± 8 years. The frequency of diabetes mellitus, hypertension, and dyslipidemia were significantly higher in cases than controls. Cases had significant higher BMI (30 ± 4.48 vs. 27.3 ± 3.94 kg/m2, P=0.029). The total TFC in cases was 97.1 ± 22.9 and in controls was 79 ± 18.5, and this difference was statistically significant (P=0.005). Significantly decreased LV global strain was observed in HFpEF cases than in controls (-17.6 ± 2.14 % versus -19.5 ± 1.98%, P < 0.001). In cases with a higher TFC, the LV global strain decrease was more pronounced. There was a significant correlation between the LV global strain and total TFC (r=-0.470 and P=0.009). Conclusion: Patients with HFpEF exhibited higher total TFC reflecting more affected coronary microvasculature. Those patients had reduced LV global strain. Coronary microvascular dysfunction probably leads to alteration of myocardial performance.

13.
Elife ; 112022 12 08.
Article in English | MEDLINE | ID: mdl-36476569

ABSTRACT

The eLife Early-Career Advisory Group discusses eLife's new peer review and publishing model, and how the whole process of scientific communication could be improved for the benefit of early-career researchers and the entire scientific community.


Subject(s)
Peer Review , Communication
14.
Aging Clin Exp Res ; 34(8): 1873-1883, 2022 Aug.
Article in English | MEDLINE | ID: mdl-35275374

ABSTRACT

AIM: We estimated the proportion and severity of cognitive disorders in an unselected population of patients referred for transcatheter aortic valve implantation (TAVI). Second, we describe clinical and cognitive outcomes at 1 year. METHODS: Eligible patients were aged ≥ 70 years, with symptomatic aortic stenosis and an indication for TAVI. The Montreal Cognitive Assessment (MoCA) was used to assess cognitive dysfunction (CD), defined as no CD if score ≥ 26, mild CD if 18-25; moderate CD if 10-18, and severe CD if < 10. We assessed survival and in-hospital complications at 6 months and 1 year. RESULTS: Between June 2019 and October 2020, 105 patients were included; 21 (20%) did not undergo TAVI, and thus, 84 were analyzed; median age 85 years, 53.6% females, median EuroScore 11.5%. Median MoCA score was 22 (19-25); CD was excluded in 18 (21%), mild in 50 (59.5%), moderate in 15 (19%) and severe in 1. Mean MoCA score at follow-up was 21.9(± 4.69) and did not differ significantly from baseline (21.79 (± 4.61), p = 0.73). There was no difference in success rate, in-hospital complications, or death across CD categories. CONCLUSION: The clinical course of patients with mild or moderate CD is not different at 1 year after TAVI compared to those without cognitive dysfunction.


Subject(s)
Aortic Valve Stenosis , Cognitive Dysfunction , Heart Valve Prosthesis Implantation , Transcatheter Aortic Valve Replacement , Aged, 80 and over , Aortic Valve/surgery , Aortic Valve Stenosis/surgery , Cognition , Cognitive Dysfunction/epidemiology , Cognitive Dysfunction/etiology , Female , Humans , Male , Prevalence , Risk Assessment , Risk Factors , Severity of Illness Index , Time Factors , Transcatheter Aortic Valve Replacement/adverse effects , Treatment Outcome
15.
Sci Total Environ ; 807(Pt 2): 150845, 2022 Feb 10.
Article in English | MEDLINE | ID: mdl-34627906

ABSTRACT

Estrogens, such as the 17ß-estradiol (E2) and the 17α-ethinylestradiol (EE2), have been regarded as a global threat to aquatic ecosystems due to their pseudo-persistence, their high estrogenic activity and their toxicity towards non-target species. Data regarding their ecotoxicological effects on marine calanoid copepods are very scarce. In this study, the calanoid copepod Acartia clausi was used as a model organism for estrogens exposure in marine pelagic ecosystems. Lethal effects of estrogens on A. clausi life-stages (Embryos, one day old nauplii: N1, three day old nauplii: N3, copepodites: C1-C3 and adults: C6) were investigated using 48 h acute tests. Copepods showed stage-specific responses against E2 and EE2 acute exposure. The most resistant life stage was N1 with LC50 values > 1500 µg L-1 and >5000 µg L-1, respectively for E2 and EE2. For N3, C1-C3, and C6, sensitivity to estrogens decreased with age and survival was affected at concentrations above those detected in the environment reflecting low estrogens acute toxicity for these life stages. In contrast, embryonic stage revealed high vulnerability to E2 and EE2 acute effects. Embryos showed non-monotonic dose-response and hatching success was significantly reduced at low realistic concentrations of E2 (0.005, 0.5, and 5 µg L-1) and EE2 (0.05 and 5 µg L-1). Survival, development and sex ratio of A. clausi to EE2 exposure at 1 and 100 µg L-1 were also determined during a life cycle experiment. Fitness of the females of the generation F0 was evaluated by measuring lifespan, prosome length and egg production. The main observed effects were the decrease of females' prosome length, the feminization of the population and the reduction of the egg production for the generation F0 at 100 µg L-1 of EE2. This concentration is above those reported in the environment indicating the tolerance of A. clausi to EE2 at environmentally relevant concentrations.


Subject(s)
Copepoda , Ethinyl Estradiol , Animals , Ecosystem , Estradiol , Ethinyl Estradiol/toxicity , Female , Reproduction , Sex Ratio , Sexual Development
16.
Sci Rep ; 11(1): 20031, 2021 Oct 08.
Article in English | MEDLINE | ID: mdl-34625608

ABSTRACT

In this article, new insights about the metals-porphyrin complexes are proved by analyzing the zinc, nickel and chromium adsorption process over the well-known porphyrin macromolecule. The use of the quartz crystal microbalance (QCM) apparatus allows the control of the complexation systems' experimental adsorption data operating at four temperatures. The experimental results and the physical models reveal that the zinc and nickel complexation processes are to be examined using the mono layer adsorption model. While, the double layer model describes the interaction between the chromium compound and the porphyrin. Actually, the three metals are shown to be adsorbed by a multi-docking process in the physicochemical description. The endothermic character of the investigated processes is shown through the appropriate data of the principal parameter adsorbent sites' density. Hence, several porphyrin sites are exclusively stimulated at high temperature. The parameters of van del Waals, depicting the influences of the lateral interactions, explain the nickel isotherms down trend. The chemical bonds are shown to be carried out between the zinc and the porphyrin through the calculated adsorption energies. Considering the thermodynamic study, and referring to the configurational entropy and the free enthalpy, it is to be noted that the disorder peak of the three mechanisms is reached when the equilibrium concentration is equal to the energetic parameters' values for each system. The nickel enthalpy revealed for high concentration that the adsorbates' lateral interactions disapproved the nickel chloride adsorption. The free enthalpy trends, that observed two stability states of the chromium compound, confirmed the chromium double layer mechanism.

17.
Sci Rep ; 11(1): 8316, 2021 Apr 15.
Article in English | MEDLINE | ID: mdl-33859307

ABSTRACT

A quartz crystal adsorbent coated with 5,10,15,20-tetrakis(4-methylphenyl) porphyrin was used to examine the complexation phenomenon of three metallic ions [aluminum(III), iron(III) and indium(III)]. The aim is to select the appropriate adsorbate for metalloporphyrin fabrication. The equilibrium adsorption isotherms of tetrakis(4-methylphenyl) porphyrin were performed at four temperatures (from 300 to 330 K) through the quartz crystal microbalance (QCM) method. Subsequently, the experimental data were analyzed in order to develop a thorough explanation of the complexation mechanisms. The experimental results indicated that the aluminum(III) chloride is the adequate material for metalloporphyrin application. Theoretical investigation was established through physics adsorption models in order to analyze the experimental isotherms. The AlCl3 isotherms were modeled via a single-layer adsorption model which is developed using the ideal gas law. Whereas, the FeCl3 isotherms were interpreted via a single-layer adsorption which includes the lateral interactions parameters (real gas law), indicating the lowest stability of the formed iron-porphyrin complex. The participation of the chloride ions in the double-layers adsorption of InCl3 was interpreted via layer by layer formulation. Interestingly, the physicochemical investigation of the three adopted models indicated that the tetrakis(4-methylphenyl) porphyrin adsorption was an endothermic process and that the aluminum(III) chloride can be recommended for an industrial application because it presents the highest adsorption energy (chemical bonds with porphyrins).

18.
Environ Sci Pollut Res Int ; 28(17): 21978-21990, 2021 May.
Article in English | MEDLINE | ID: mdl-33415623

ABSTRACT

Excessive use of nickel oxide nanoparticles (NiO NPs) in various industrial and commercial products can lead to various negative effects in human and environmental health due to their possible discharge into the environment. Nerveless, information about their ecotoxicological effects on marine organisms are lacking. Copepods are good ecotoxicological models because of their high sensitivity to environmental stress and their key role in the marine food webs. In this study, 48 h acute tests were conducted on the marine planktonic copepod Centropages ponticus to assess lethal and sublethal toxicities of NiO NPs. The results revealed LC50 (48 h) of 4 mg/L for adult females. Aggregation and settling of NiO NPs were observed at concentrations ≥ 2 mg/L. Exposure to sublethal concentrations (≥ 0.02 mg/L for 48 h) had significant negative effects on reproductive success in C. ponticus. Egg production after 24 h and 48 h decreased by 32% and 46%, respectively at 0.02 mg/L and 70% and 82%, respectively, at 2 mg/L. Hatching success was reduced by 70% and 79% at 2 mg/L for eggs produced after 24 h and 48 h respectively. Antioxidant enzymatic activity increased significantly with NiO NP concentration and time, indicating that NiO NPs can cause oxidative stress in C. ponticus even under short-term exposure, while significant inhibition of acetylcholinesterase activity at 2 mg/L after 48 h suggests neurotoxic effects of NiO NPs.


Subject(s)
Copepoda , Metal Nanoparticles , Nanoparticles , Animals , Biomarkers , Female , Humans , Metal Nanoparticles/toxicity , Nickel , Oxidative Stress , Reproduction
19.
Macromolecules ; 53(20): 8951-8959, 2020 Oct 27.
Article in English | MEDLINE | ID: mdl-33132419

ABSTRACT

We report a side group modification strategy to tailor the structure of a polymer of intrinsic microporosity (PIM-1). PIM-1 with an average of ∼50% of the repeat units converted to tetrazole is prepared, and a subsequent reaction then introduces three types of pseudo-ionic liquid tetrazole-like structures (PIM-1-ILx). The presence of pseudo-ionic liquid functional groups in the PIM-1 structure increases gas selectivities for O2/N2 and CO2/N2, while it decreases pure-gas permeabilities. The overall gas separation performance of PIM-1-ILx is close to the 2008 Robeson upper bound. Since the tetrazoles are versatile groups for building a wide variety of ionic liquids, the modification method can be expanded to explore a broad spectrum of functional groups.

20.
Sci Total Environ ; 727: 138621, 2020 Jul 20.
Article in English | MEDLINE | ID: mdl-32498212

ABSTRACT

Copepods are excellent bioindicators of climate change and ecosystem pollution in anthropized coastal waters. This work reviewed the results of previous studies examining changes in egg production rate (EPR), hatching success (HS), and nauplius survival rate (NSR) in natural conditions and in the presence of pollutants, including heavy metals and organic contaminants such as polycyclic aromatic hydrocarbons (PAHs) and persistent organic pollutants (POPs). At high concentrations, cadmium and silver induce an increase in EPR in the copepods Acartia tonsa and Acartia hudsonica, while exposure to mercury decreases EPR in adults by 50%. All three metals affect HS, with mercury inducing a stronger effect than cadmium and silver. Cadmium affects reproductive traits in Centropages ponticus, decreasing EPR and particularly HS. Furthermore, copper and chromium at high concentrations induce significant decreases in eggs per female in Notodiaptomus conifer. In terms of organic contaminant and Polycyclic Aromatic Hydrocarbons (PAHs), Eurytemora affinis is reported to be affected by naphthalene, 2-methylnaphthalene, 2,6-dimethylnaphthalene, and 2,3,5-trimethylnaphthalene and can thus be used in ecotoxicity studies, but only if the exposure time is high. Acartia tonsa shows significant reductions in EPR and HS at high concentrations of fluoranthene, phenanthrene, and pyrene. However, the response to Persistent Organic Pollutants (POPs) such as pentachlorophenol (PCP) and 1,2-dichlorobenzene (DCB) differs. In E. affinis, EPR increases with DCB, but HS falls to <1%. EPR increases when the species is exposed overnight, but HS remains low in the presence of DCB. Based on these results, we developed a novel copepod reproductive trait index (CRT-Index) for use in marine ecotoxicology surveys and tested in some simple cases. We show that copepods are good candidates as models for ecotoxicology studies, in particular using reproductive traits (EPR, HS and NSR) because of their sensitivity to a wide range or pollutants.


Subject(s)
Copepoda , Animals , Ecosystem , Ecotoxicology , Plankton , Water Pollutants, Chemical
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