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1.
The present study focused on the assessment of oxidative stress induction by pesticides such as carbamates which are widely used as insecticides and nematicides and contaminate aquatic ecosystems on certain biomarkers in liver of common carp (Cyprinus carpio L.). Biomarkers selected for stress monitoring were malondialdehyde (MDA), an index of lipid peroxidation, and antioxidant defence system enzymes, mainly catalase (CAT), glutathione reductase (GR), and glutathione-S-transferase (GST) activities in liver of fish exposed to 0, 10, 50, or 100?µg?L?1 of carbofuran for 4, 15, or 30 days. Oxidative stress was found in liver of common carp exposed to carbofuran which was manifested by a decrease in CAT and GR activities after 4 and 30 days of exposure. An adaptive response was probably produced since at day 15 no modifications in the CAT activity and increased GR activity were observed. In addition, a decrease in MDA content with the highest concentration of carbofuran used was found after 30 days of exposure. However, no significant changes were found in GST activity showing a varied response. The results concerning oxidative and antioxidant profiles indicate that subchronic exposure to the insecticide carbofuran is capable of inducing oxidative stress in fish.  相似文献   

2.
SO2长期吸入对大鼠肺组织基因表达谱的影响   总被引:2,自引:0,他引:2  
采用Affymetrix的基因芯片(RAE230A)技术,研究了SO2长期动态吸入(14mg/m3,1h/d,共30d)后大鼠肺组织基因表达谱的改变.结果表明,与对照组(CK)相比,SO2长期吸入后大鼠肺组织表达上调的基因有173个,其中包括79个已知基因和94个新基因,而表达下调的基因有85个,其中包括46个已知基因和39个新基因.表明:(1)长期吸入SO2的大鼠肺基因表达谱与其CK相比,表达有差异的基因涉及到脂肪酸代谢、免疫、炎症、氧化应激、原癌基因、肿瘤抑制基因和细胞外基质等,表明低剂量长期吸入SO2在体内的机理非常复杂;(2)SO2高剂量短期吸入与低剂量长期吸入后,大鼠肺组织基因表达谱的改变很不一致,表明二者在体内的作用机理不同;(3)SO2可引起多种基因的表达发生改变,这意味着多种基因的表达是易变的、不稳定的,在肺组织中可能存在着SO2诱发的表达不稳定型基因组.表1参19  相似文献   

3.
To understand acute toxicity and oxidative stress of perfluorinated compounds in the freshwater ecosystems, we exposed freshwater mussels (Unio ravoisieri) to perfluorooctane sulfonate (PFOS), over a range of concentrations from 10 to 100?mg/L, in a laboratory experiment. Lethal concentration (LC50) was of about 65.9?mg/L after 96?h of exposure. The oxidative stress was assessed in gill and digestive gland of the freshwater mussels after 7 days of exposure to different nominal PFOS concentrations (C1=?2?mg/L, C2?=?6?mg/L and C3=?10?mg/L). C1 and C2 increased significantly (p?<?.05) the superoxide dismutase activity in both tissues compared, while the highest C3 decreased the enzyme activity. This implements an unfavourable response that highlights the excess of reactive oxygen species produced after contamination. The Catalase activity was also increased by about 40.05% and 66.63%, respectively, in gill and digestive gland after exposure to C3. The Malondialdehyde (MDA) level was increased in both gill and digestive gland in a concentration-dependent pattern. In contrast, the contamination of U. ravoisieri by PFOS did not affect the acetylcholinesterase activity in both organs (p?>?.005). These results provided information on potential biomarkers that could be effectively applied for the monitoring of freshwater ecosystem using indicator species such as U. ravoisieri.  相似文献   

4.
Hexavalent chromium-tolerant (1500?mg/L) bacterium MW1 was isolated from harbour water of Paradip Port and evaluated for Cr(VI) reduction potential. The isolate was identified as Exiguobacterium indicum by biochemical and 16S rRNA gene sequence methods. Salt tolerance of the bacterium was evaluated in a wide range of NaCl concentrations (0.5–13%, w/v). The Cr(VI) reduction of the strain was evaluated and optimised with varied Cr(VI) concentrations (100–1000?mg/L), pH (5.0–9.0), temperature (30–40°C) and shaking velocity (100–150?rpm) in two different minimal media (M9 and Acetate). Under optimised conditions, after 192?h of incubation nearly 92%, 50% and 46% reduction in the M9 minimal medium and 91%, 47% and 40% reduction in the acetate minimal medium were observed for 100, 500 and 1000?mg/L of Cr(VI), respectively. The exponential rate equation for Cr(VI) reduction yielded higher rate constant value, that is, 1.27?×?10?2?h?1 (M9) and 1.17?×?10?2?h?1 (Acetate) in case of 100?mg/L and became lower for 500 and 1000?mg/L Cr(VI) concentrations. Further, the association of bacterial cells with reduced product was ascertained by Fourier transform infrared spectrometer, UV–Vis–DRS and field-emission scanning electron microscope–energy-dispersive X-ray analyses. The above study suggests that the higher reducing ability of the marine bacterium E. indicum MW1 will be suitable for Cr(VI) reduction from saline effluents.  相似文献   

5.
In 2010 the pond dam of an aluminium manufacturing plant in Hungary broke and flooded many towns with toxic red mud. At least 10 people were dead and over 150 hospitalized. Bauxite residue is often referred as red mud due to the colour of the bauxite ore and iron oxides. Red mud is separated during the refining process. The production of 1 t of alumina generally results in the creation of 1–1.5 t of red mud. Red mud is toxic for the environment due to high alkalinity, salinity and trace metals. Here, we used the plant Arundo donax L. (giant reed) to uptake trace metals and decrease salinity and pH of red mud. We measured plant toxicity, trace metal availability and biomass production. Results show a 25 % decrease in electrical conductivity of red mud and a 6 % decrease in electrical conductivity of mud-polluted soil. Giant reed cultivation decreases available Cd, Pb, Co, Ni and Fe. Biomass of giant reed seedlings in red mud and mud/control soil mixture was increased by 40.4 and 47.2 %, respectively, comparing with control soil. Our findings show that giant reed is promising to decontaminate soils contaminated by red mud.  相似文献   

6.
Shewanella oneidensis MR-1 was acclimated to grow with Cr(VI) of 190 mg/L. • Whole genomes from 7 populations at different acclimation stages were sequenced. • Gene mutations mainly related to efflux pumps and transporters. • An adaptation mechanism of MR-1 to high concentration of Cr(VI) was proposed. Acclimation is the main method to enhance the productivity of microorganisms in environmental biotechnology, but it remains uncertain how microorganisms acquire resistance to high concentrations of pollutants during long-term acclimation. Shewanella oneidensis MR-1 was acclimated for 120 days with increasing hexavalent chromium (Cr(VI)) concentrations from 10 to 190 mg/L. The bacterium was able to survive from the highly toxic Cr(VI) environment due to its enhanced capability to reduce Cr(VI) and the increased cell membrane surface. We sequenced 19 complete genomes from 7 populations of MR-1, including the ancestral strain, the evolved strains in Cr(VI) environment on days 40, 80 and 120 and their corresponding controls. A total of 27, 49 and 90 single nucleotide polymorphisms were found in the Cr(VI)-evolved populations on days 40, 80 and 120, respectively. Nonsynonymous substitutions were clustered according to gene functions, and the gene mutations related to integral components of the membrane, including efflux pumps and transporters, were the key determinants of chromate resistance. In addition, MR-1 strengthened the detoxification of Cr(VI) through gene variations involved in adenosine triphosphate binding, electron carrier activity, signal transduction and DNA repair. Our results provide an in-depth analysis of how Cr(VI) resistance of S. oneidensis MR-1 is improved by acclimation, as well as a genetic understanding of the impact of long-term exposure of microorganisms to pollution.  相似文献   

7.
非生物胁迫诱导青蒿素生物合成基因的表达   总被引:3,自引:0,他引:3  
对离体培养青蒿试管苗中3个青蒿素合成相关基因的非生物胁迫诱导表达模式进行了初步研究.半定量RT-PCR测定结果表明,当暴露于冷、热和紫外光后,青篙植株的紫穗槐-4,11-二烯合酶基因(ADS)和细胞色素P450单加氧酶基因(CYP71AV1)转录上调;相反,在未经胁迫处理的情况下,ADS和CYP71AV1基因的表达水平较低,而在胁迫处理前后细胞色素P450还原酶基因(CPR)转录所产生的mRNA均保持恒定.同时,冷胁迫的诱导效果也得到实时荧光定量RT-PCR测定数据的支持.经低温锻炼的青蒿试管苗,其ADS和CYP71AV1基因的转录产物拷贝数比对照分别提高11倍和7倍,而CPR基因的mRNA拷贝数与对照基本持平.短暂预冷处理还可显著提高青蒿试管苗的青蒿素含量,达到7.5~8.8 mg/g干重,比对照提高66.7%~95.6%,为进一步探索利用环境胁迫促进青蒿素高产的新途径提供了可能性.图2表3参21  相似文献   

8.
9.
为探究褐牙鲆(Paralichthys olivaceus)幼鱼抗氧化系统酶活力及相关基因表达在悬浮物胁迫下的变化情况,设计了浓度为5 000、10 000 mg·L-1悬浮物水体对褐牙鲆(14.53 cm±1.58 cm)肌肉、肝脏、鳃及血液总超氧化物歧化酶(T-SOD)、谷胱甘肽转移酶(GST)、过氧化氢酶(CAT)酶活力及SOD2、GST、CAT的mRNA转录水平表达变化情况。结果显示:在悬浮物胁迫24 h或者48 h时,4种组织3种酶活力具有升高的趋势(P0.05);4种组织的T-SOD酶活力在96 h均高于对照组(P0.05),肌肉、鳃丝及血液中SOD2基因相对表达量96 h实验组低于对照组(P0.05);肌肉中CAT酶活力呈现先升高再降低趋势,鳃中CAT基因相对表达量呈现先降低、再升高、再降低的趋势;肝脏、鳃、血液中GST酶活力在悬浮物胁迫下呈现升高趋势,4种组织GST基因相对表达量在12~24 h时呈现升高趋势。研究表明:悬浮物对褐牙鲆抗氧化酶活力及相关基因的表达具有一定的影响,血液中3种酶活力变化幅度最大,鳃中3种基因相对表达水平变化幅度最大,这与血液及鳃参与呼吸作用过程有关;抗氧化酶活性及基因相对表达变化趋势并不完全一致。本研究可为揭示褐牙鲆应对悬浮物胁迫的耐受机制及褐牙鲆耐悬浮物品种选育提供基础数据。  相似文献   

10.
• Functional groups of AM and EDTA in composite increased removal of Cr(VI) and CR. • Removal process reached equilibrium within 30 min and was minimally affected by pH. • Elimination of Cr(VI) was promoted by coexisting CR. • Adsorption process of CR was less influenced by the presence of Cr(VI). • Mechanisms were electrostatic attraction, surface complexation and anion exchange. We prepared ethylenediaminetetraacetic acid (EDTA)-intercalated MgAl-layered double hydroxide (LDH-EDTA), then grafted acrylamide (AM) to the LDH-EDTA by a cross-linking method to yield a LDH-EDTA-AM composite; we then evaluated its adsorptive ability for Congo red (CR) and hexavalent chromium (Cr(VI)) in single and binary adsorption systems. The adsorption process on LDH-EDTA-AM for CR and Cr(VI) achieved equilibrium quickly, and the removal efficiencies were minimally affected by initial pH. The maximum uptake quantities of CR and Cr(VI) on LDH-EDTA-AM were 632.9 and 48.47 mg/g, respectively. In mixed systems, chromate removal was stimulated by the presence of CR, while the adsorption efficiency of CR was almost not influenced by coexisting Cr(VI). The mechanisms involved electrostatic attraction, surface complexation, and anion exchange for the adsorption of both hazardous pollutants. In the Cr(VI) adsorption process, reduction also took place. The removal efficiencies in real contaminated water were all higher than those in the laboratory solutions.  相似文献   

11.
Inorganic selenium (Se) is absorbed and enriched by plants and converted into a stable and nutritionally important organic form, which subsequently when consumed by humans or animals results in increased Se tissue levels. Brassica is one of the most potent Se-enriched plants. The aim of this study was to compare differences in Se enrichment between two predominant Brassica plants namely Brassica rapa Linn L. and Brassica tumida Tsenet Lee L. on Se metabolic parameters. Plants exposed to soil Se levels (0, 0.5, 1, 2.5 or 5?mg/kg) were examined on the activity of glutathione peroxidase (GSH-Px), Se levels and expression of Se metabolism related genes using soil pots. Data showed that activities of GSH-Px in leaf and root of the two Brassica species were significantly increased in the presence of Se at 2.5?mg/kg. Se concentrations of leaf, stem and root in B. tumida Tsenet Lee L. and B. rapa Linn L. rose from 0.31 to 21.84-fold (leaf), 1.15 to 15.16-fold (stem) and 2.11 to 15.26-fold (root) in the presence of metal in a concentration-dependent manner. The highest expression levels of adenosine triphosphate (ATP), ATP sulfurylase (APS), selenocysteine methyltransferase (SMT), serine acetyltransferase (SAT), cysteine desulfurase (CysD) and S-adenosyl-l-Met:l-Met S-methyltransferase (MMT) in leaf of B. rapa Linn L. were found at 1?mg/kg Se. The highest expression levels of ATP, APS, SMT, SAT, CysD and MMT in leaf of B. tumida Tsenet Lee L. were observed at 2.5?mg/kg Se. The Se concentrations in leaf, stem and root of B. rapa Linn L. were higher than in B. tumida Tsenet Lee L. under the same soil Se level conditions. At the same Se level, differences in the expression of Se-related genes were observed between these two Brassica species. Our observations may be used to optimize the utilization of Brassica as a nutritional source of Se by growing this plant under certain soil conditions.  相似文献   

12.
With juvenile fish as the subject, the effects of low concentration ammonia on antioxidant system were studied using Mugil cephalus. Samples of gill and liver tissue were obtained from 0.35, 0.70, 1.5 and 3?mg/L ammonia groups at 0, 5, 10, 15 and 20 days of exposure, at which times the biomarkers were measured. Results showed that gill malondialdehyde (MDA) content exhibited an initial significant increase (p?≤?0.05) at unionised ammonia concentrations of 0.70, 1.5 and 3.0?mg/L on day 5, followed by subsequent declines, while liver MDA levels exhibited significant increases (p?≤?0.05) at unionised ammonia concentrations of 1.5?mg/L starting on day 10 and at 3.0?mg/L starting on day 5. With exposure to ammonia at different concentrations, Na+-K+-ATPase activity in liver and gill decreased over time. The Na+-K+-ATPase activity was negatively related to ammonia concentration from 0.70 to 3.0?mg/L. Overall, our results show that MDA and Na+-K+-ATPase, evaluated here as potential biomarkers of ammonia exposure, exhibited responses to sublethal concentrations of ammonia that were concentration dependent.  相似文献   

13.
In this research, epigenetic effects of bisphenol A (BPA) on human breast cancer MCF-7 cells were analyzed. Genome-wide DNA methylation and gene expression were analyzed in MCF-7 cells exposed to BPA (10?5 and 10?6 mol/L for 5 weeks). No significant changes in the global level of 5-methyl-2′-deoxycytidine and 5-hydroxymethyl-2′-deoxycytidine were observed. DNA methylation profiling analysis indicated that BPA exposure resulted in the hypermethylation of FOXK2, LKB1, LMX1A and CUGBP2 and the hypomethylation of PTPRN2, TRIM27, BCAS3 and ZNF423. Decreased expression of apoptosis genes (P38 and BCL2L1) and increased expression of chemokine (Cxcl2 and ccl20) were detected. Changes of these genes were speculated to affect the ERα-related cell growth as well as cell apoptosis.  相似文献   

14.
Sorghastrum Nutans L. Nash is used as an adsorbent for the removal of Cr(VI) from wastewater. Adsorption coupled reduction i.e. indirect reduction is the mechanism of Cr(VI) removal by the biomaterial. The adsorbent surface became highly positively charged at lower pH, adsorption rate of Cr(VI) is faster and reduction reaction also accelerates at lower pH since the binding of negatively charged Cr(VI) ion species to the cationic groups is enhanced and protons take part in this reaction. The adsorbent is characterised by using XRD, FTIR, SEM and EDAX analysis. OH bending, CN stretching/bending and NH stretching play a major role in Chromium adsorption. Experimental values follow pseudo-second order reaction and Langmuir adsorption isotherm. Surface diffusion is the rate controlling mechanism for the process. The maximum percentage of Cr(VI) removal obtained is 75.5% with 7?g/L dosage at pH 1.3 and adsorbate concentration was 100?mg/L. From the normal probability, residual, contour, 3D surface, main effect and interaction plot along with t-test, ANOVA, and F-test, it is observed that pH has the most significant effect on the percentage removal followed by adsorbent dosage and time. The adsorbate concentration has the least effects and interaction effects are found to be significant.  相似文献   

15.
狼尾草根系对阿特拉津长期胁迫的氧化应激响应   总被引:2,自引:0,他引:2  
通过盆栽实验研究了抗性植物狼尾草根部丙二醛(MDA)、脯氨酸(Pro)、抗坏血酸(As A)含量及超氧化物歧化酶(SOD)、谷胱甘肽还原酶(GR)等氧化应激生理指标对不同浓度阿特拉津长期(48 d)胁迫的响应规律。结果表明:当阿特拉津胁迫浓度分别高于20 mg·kg~(-1)和50 mg·kg~(-1)时,狼尾草根系的MDA与Pro含量较对照组显著升高(P0.05);随着阿特拉津胁迫浓度的增加,狼尾草根部SOD和GR活性呈先升高后降低的趋势,其中当阿特拉津胁迫浓度为20 mg·kg~(-1)时,SOD和GR活性达到最大值;供试植物根系中As A含量与阿特拉津胁迫浓度呈正相关。综上,中低浓度(≤20 mg·kg~(-1))阿特拉津处理没有对狼尾草的根系产生明显的氧化胁迫效应,狼尾草根系的上述抗氧化应激生理指标对于发挥阿特拉津抗性起着重要的作用。  相似文献   

16.
采用营养液培养法和二因素完全实验设计,在5 mg.L-1Cr(Ⅵ)、Ni复合污染条件下对22种植物进行筛选实验,选取富集量较高且生长较快的旱伞草Cyperus alternifolius,分析其对Cr(Ⅵ)、Ni的累积规律及生理生化效应。结果表明:(1)在Cr(Ⅵ)、Ni复合污染胁迫下,旱伞草生长状况良好,对铬、镍具有较高的富集能力;(2)在Cr(Ⅵ)、Ni复合污染下,Cr(Ⅵ)抑制旱伞草对Ni的吸收,Ni促进旱伞草对Cr的吸收;(3)分别在单因素Cr(Ⅵ)、Ni的胁迫下,SOD和CAT活性随着Cr(Ⅵ)、Ni质量浓度(0-50 mg.L-1)的增加都是先上升后下降,MDA总体都呈增加的趋势;(4)在Cr(Ⅵ)胁迫下,旱伞草地上部富集总铬的含量较高,但六价铬含量较低,对Cr(Ⅵ)的转化率最大可达到97.00%。研究表明,旱伞草是一种修复Cr(Ⅵ)、Ni污染很有潜力的物种。  相似文献   

17.
纳米氧化镍(nNiO)作为一种广泛使用的纳米颗粒,其水生毒理效应研究还很有限。为探索n Ni O对海洋贝类的毒性机制,本研究将长牡蛎(Crassostrea gigas)置于不同浓度(0、1、10、100 mg·L~(-1))的n Ni O中暴露96 h,分别测定鳃和消化腺组织的丙二醛(MDA)含量和超氧化物歧化酶(SOD)、过氧化物酶(POD)以及过氧化氢酶(CAT)活性,并通过实时荧光定量PCR技术测定了鳃和消化腺中应激蛋白HSP70和AOX基因的表达变化。结果显示:在100 mg·L~(-1)n Ni O处理下,2种组织中MDA含量均显著性升高(P0.01),显示纳米颗粒造成了长牡蛎的脂质过氧化,并可能引起相应的氧化损伤。同时,n Ni O暴露也诱导了长牡蛎抗氧化酶(SOD、CAT和POD)活性的改变。其中,SOD和CAT活性在10 mg·L~(-1)浓度处理组达到最高,而POD活性在1 mg·L~(-1)浓度组即达最高值。在高浓度n Ni O(100 mg·L~(-1))胁迫下,3种抗氧化酶的活性均比低浓度(1和10 mg·L~(-1))处理组降低,表明抗氧化酶的保护作用在较低浓度暴露下更有效;而热激蛋白(hsp70)和交替氧化酶(aox)基因却分别在长牡蛎消化腺和鳃组织中上调表达(P0.01),并表现出一定的组织差异。说明高浓度纳米颗粒暴露中主要是应激蛋白发挥了作用。本文结果为纳米氧化镍对海洋双壳贝类的毒性机制研究及生态风险评估提供了基础数据。  相似文献   

18.
为了解全氟辛烷磺酸盐(perfluorooctane sulfonate, PFOS)暴露对半滑舌鳎(Cynoglossus semilaevis)免疫功能的影响,在实验室条件下,运用RT-PCR方法分析了PFOS暴露对半滑舌鳎热休克蛋白hsp70、hsp90、C型凝集素(c-type lectin)和细胞色素c氧化酶(cytochrome c oxidase, cox)等4种免疫相关基因表达水平的影响。实验测定了上述4种基因在半滑舌鳎肝、鳃、肠及肌肉4种不同组织中随时间(0、24 h、48 h、96 h和7 d)的表达变化情况。结果表明,在4种组织中,hsp70基因的表达与对照相比为上调,其中,肝组织hsp70基因的表达量显著高于其他各组织,且表达高峰值的出现也早于其他各组织;hsp90基因在肝和鳃组织中表达量随时间不同而波动,在肠组织中表达上调,在肌肉中表达显著下调;c-type lectin基因表达量与对照组相比表达显著下调或无明显差异;cox基因在肝组织和肠组织中表达下调,在鳃和肌肉中表达上调。上述研究结果表明,PFOS能引起免疫相关基因的表达变化,对半滑舌鳎具有潜在的免疫毒性。肝组织中各免疫基因对PFOS胁迫的响应高于其他组织。本研究可为阐明全氟辛烷磺酸盐对半滑舌鳎的免疫毒性提供基础数据。  相似文献   

19.
This study assessed the distribution of heavy metals in soil and their subsequent accumulation in plants at a site at Umudike, Nigeria, that had been contaminated by agrochemicals. Soil and plant samples were analysed for zinc (Zn), chromium (Cr) and cadmium (Cd). The highest concentrations of Zn (251.50 mg/kg) and Cd (61.33 mg/kg) were obtained at a soil depth of 0–10 cm. The highest concentrations of Zn (16.52 mg/kg), Cd (27.12 mg/kg) and Cr (164.07 mg/kg) were accumulated by Baphia nitida. The levels of Cd, Cr and Zn in soil were 27.97–61.33, 24.97–45.43 and 148.57–251.50 mg/kg, and their concentrations in B. nitida were 16.18–27.13, 97.99–164.07 and 0.10–16.52 mg/kg, respectively. There were significant correlations between Cd and Cr and Cd and Zn in soil, as well as between Cd and Cr in plants. The concentration of Cd in soil reflected a state of pollution relative to Dutch criteria for soil and the FAO/WHO Codex Alimentarius Commission.  相似文献   

20.
Qianghua Xu  Yang Liu 《Marine Biology》2011,158(10):2161-2172
The swimming crab, Portunus trituberculatus, is an important marine fishery and aquaculture species. Although P. trituberculatus is a euryhaline species, water salinity condition influenced its distribution, migration route, and artificial propagations. To investigate gene expression in the P. trituberculatus exposed to different salinity stresses, 2426 expressed sequence tags (ESTs) from gill cDNA library were selected to spot on a cDNA microarray chip. In total, 417 differentially expressed genes were identified and grouped into eight clusters by hierarchical clustering analysis. Approximately 71.5% of grouped genes belonged to three independent expression patterns, indicating that these three expression patterns may represent three important stress tolerance pathways or networks in P. trituberculatus. Moreover, our cDNA microarray data suggested that there were differences in gene expression patterns of P. trituberculatus for low salinity and high salinity acclimation, suggesting that two salinity challenges resulted in a wide variation of gene expression in P. trituberculatus. In addition, a series of genes such as CCAAT/enhancer-binding protein, Na/K ATPase β-subunit, and heat shock proteins (HSPs) genes were suggested to be key elements during salinity acclimation process. Overall, this work represented an important step toward understanding the molecular processes and mechanisms involved in salinity acclimation of the swimming crab.  相似文献   

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