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1.
Crit Care ; 27(1): 275, 2023 07 09.
Artigo em Inglês | MEDLINE | ID: mdl-37424026

RESUMO

BACKGROUND: The oXiris is a novel filter for continuous renal replacement therapy (CRRT) featuring an adsorption coating to adsorb endotoxins and remove inflammatory mediators. Given that no consensus has been reached on its potential benefits in treating sepsis, a meta-analysis was conducted to assess its impact on the clinical outcomes of this patient population. METHODS: Eleven databases were retrieved to find relevant observational studies and randomized controlled trials. The Newcastle-Ottawa Scale and the Cochrane Risk of Bias Tool were used to assess the quality of the included studies. The Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) process was employed to assess the certainty of evidence. The 28-day mortality was the primary outcome. Secondary outcomes were 7-, 14-, and 90-day mortality, length of intensive care unit (ICU) and hospital stay, ICU and hospital mortality, norepinephrine (NE) dose, interleukin-6 (IL-6) and lactate levels, and Sequential Organ Failure Assessment (SOFA) score. RESULTS: The meta-analysis, pooling data from 14 studies, involving 695 patients, showed significant reductions in 28-day mortality [odds ratio (OR) 0.53; 95% confidence interval (CI) 0.36-0.77, p = 0.001] and length of ICU stay [weighted mean difference (WMD) - 1.91; 95% CI - 2.56 to - 1.26, p < 0.001)] in patients with sepsis using the oXiris filter compared to other filters. Besides, the SOFA score, NE dose, IL-6 and lactate levels, and 7- and 14-day mortalities were lower in the oXiris group. However, the 90-day mortality, ICU and hospital mortality, and length of hospital stay were comparable. The quality assessment of the ten observational studies indicated intermediate to high quality (average Newcastle-Ottawa score: 7.8). However, all four randomized controlled trials (RCTs) had an unclear risk of bias. The evidence for all outcomes had a low or very low level of certainty because the original study design was mainly observational studies and the RCTs included had an unclear risk of bias and a small sample size. CONCLUSION: The treatment with the oXiris filter during CRRT in sepsis patients may be associated with lower 28-, 7-, and 14-day mortalities, lactate levels, SOFA score, NE dose, and shorter length of ICU stay. However, due to the low or very low quality of evidence, the effectiveness of oXiris filters was still uncertain. Besides, no significant difference was observed for the 90-day mortality, ICU and hospital mortality, and length of hospital stay.


Assuntos
Terapia de Substituição Renal Contínua , Sepse , Humanos , Interleucina-6 , Adsorção , Lactatos/uso terapêutico
3.
Int J Mol Sci ; 21(15)2020 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-32722594

RESUMO

In crustaceans, the regulation of sex differentiation is mediated by insulin-like androgenic hormone (IAG) and crustacean female sex hormone (CFSH). CFSH is reported to inhibit IAG gene (Sp-IAG) expression in the mud crab Scylla paramamosain, but the regulatory mechanism is not well understood. A 2674 bp 5' flanking Sp-IAG contains many potential transcription factor binding sites. In this study, analysis of serially deleted 5' flanking Sp-IAG and site-directed mutation (SDM) of transcription factor binding sites of the same gene showed that the promoter activity of reporter vectors with Sox-5-binding site, signal transducers and activators of transcription (STAT)-binding site and activator protein 1 (AP-1)-binding site were significantly higher than that of vectors without these regions, suggesting that they were involved in transcriptional regulation of Sp-IAG expression. The expression analysis of these transcription factor showed that there was no difference in the level of mRNA in Sox-5 and AP-1 in androgenic gland treated with recombinant CFSH, but expression of Sp-STAT was significantly reduced, suggesting that CFSH regulates the expression of Sp-STAT, inhibiting its function to regulate Sp-IAG. Further experiment revealed that RNAi mediated Sp-STAT gene knockdown reduced the expression of Sp-IAG. These results suggested that Sp-CFSH regulates Sp-IAG by inhibiting STAT. This is a pioneering finding on the transcriptional mechanism of IAG gene in crustaceans.


Assuntos
Proteínas de Artrópodes/biossíntese , Braquiúros/metabolismo , Regulação da Expressão Gênica/fisiologia , Hormônios de Invertebrado/metabolismo , Diferenciação Sexual/fisiologia , Transcrição Gênica/fisiologia , Animais , Proteínas de Artrópodes/genética , Braquiúros/genética , Feminino , Hormônios de Invertebrado/genética
4.
J Exp Biol ; 222(Pt 21)2019 11 06.
Artigo em Inglês | MEDLINE | ID: mdl-31558587

RESUMO

C-Type allatostatins are a family of peptides that characterized by a conserved unblocked PISCF motif at the C-terminus. In insects, it is well known that C-type allatostatin has a potent inhibitory effect on juvenile hormone biosynthesis by the corpora allata. C-Type allatostatin has been widely identified from crustacean species but little is known about its roles. Therefore, this study investigated the tissue distribution patterns of C-type allatostatin and its putative receptor in the mud crab Scylla paramamosain, and further explored its potential effect on vitellogenesis. Firstly, cDNAs encoding C-type allatostatin (Sp-AST-C) precursor and its putative receptor (Sp-AST-CR) were isolated. Subsequently, RT-PCR revealed that Sp-AST-C was mainly expressed in the nervous tissue, middle gut and heart, whereas Sp-AST-CR had extensive expression in all tissues tested except the eyestalk ganglion and hepatopancreas. In addition, in situ hybridization in the cerebral ganglion showed that Sp-AST-C was localized in clusters 6 and 8 of the protocerebrum, clusters 9, 10 and 11 of the deutocerebrum, and clusters 14 and 15 of the tritocerebrum. Whole-mount immunofluorescence revealed a similar distribution pattern. Synthetic Sp-AST-C had no effect on the abundance of S. paramamosain vitellogenin (Sp-Vg) in the hepatopancreas and ovary in vitro but significantly reduced the expression of its receptor (Sp-VgR) in the ovary in a dose-dependent manner. Furthermore, Sp-VgR expression, vitellin content and oocyte diameter in the ovary were reduced 16 days after the first injection of Sp-AST-C. Finally, in situ hybridization showed that Sp-AST-CR transcript was specifically localized in the oocytes, which further indicated that the oocytes are the target cells for Sp-AST-C. In conclusion, our results suggested that the Sp-AST-C signaling system is involved in the regulation of ovarian development, possibly by directly inhibiting the uptake of yolk by oocytes and obstructing oocyte growth.


Assuntos
Braquiúros/genética , Braquiúros/imunologia , Neuropeptídeos/genética , Neuropeptídeos/imunologia , Receptores de Neuropeptídeos/genética , Receptores de Neuropeptídeos/imunologia , Sequência de Aminoácidos , Animais , Proteínas de Artrópodes/química , Proteínas de Artrópodes/genética , Proteínas de Artrópodes/imunologia , Sequência de Bases , Feminino , Perfilação da Expressão Gênica , Neuropeptídeos/química , Ovário/crescimento & desenvolvimento , Receptores de Neuropeptídeos/química , Alinhamento de Sequência , Distribuição Tecidual , Vitelogênese/genética
5.
Appl Opt ; 58(18): 5107-5114, 2019 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-31503832

RESUMO

The operational reliability directly affects the practical application of optical current transformers (OCTs) in smart substations. As the key component of the OCT, the reliability of the optical current sensor (OCS) largely determines the reliability level of the OCT. This paper proposes a reliability assessment method of the OCS based on accelerated aging tests. The failure modes and failure mechanisms of the OCS are analyzed, and the concept of OCS insertion loss variation is proposed. An allowable range of insertion loss variation is selected as the failure criterion of the OCS. From the viewpoint of the OCS measurement error generated by the quantization error of the analog-to-digital converter, the allowable range of insertion loss variation is obtained. By selecting a high temperature as the accelerated thermal stress, we design the accelerated aging test scheme of the OCS and analyze the sample test data to obtain the activation energy of the OCS insertion loss failure. Based on this activation energy, the median time to failure and instantaneous failure rate curve of the OCS at normal temperature are obtained. The results indicate that the designed OCS has an expected service life of 50 years and a low instantaneous failure rate at normal temperature. This paper provides basic critical reliability analysis data for the system reliability assessment of OCTs.

6.
Appl Opt ; 57(22): 6283-6289, 2018 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-30117854

RESUMO

Inhomogeneous media are affected by a physical or an electromagnetic field, where the off-diagonal elements of the Jones matrix are complex numbers with both real and imaginary parts. Inhomogeneities of the electromagnetic field result in the eigenvalue coordinate system changing along the light path. In this study, we used the unitary transformation to propose a Jones matrix of the inhomogeneous-field-induced medium with three physical or electromagnetic parameters: the medium's phase delay, induction angle, and inhomogeneous angle. This Jones matrix and the integral formulas of its three parameters are applicable to not only remarkable optical effects but also for the light propagation process of inhomogeneous-field-induced media.

7.
Opt Express ; 22(2): 1835-41, 2014 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-24515192

RESUMO

A tapered silica photonic crystal fiber was designed and fabricated to generate more than one octave spanning supercontinuum (from 550 nm to 1400 nm at -30 dB level), by an input pulse of 40 fs 200 pJ directly from an Yb:fiber ring laser. The low pulse energy spectrum broadening are favorable to generate the high contrast f ceo signals with low noise. The f ceo signal with 40 dB signal-to-noise ratio was detected, which helps to build a compact real-world frequency comb.

8.
Opt Lett ; 39(7): 1831-3, 2014 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-24686616

RESUMO

We report a compact Yb:fiber ring laser operated at 616 MHz. The average output power is 450 mW at a pump power of 900 mW. The dechirped pulse width is 98 fs.

9.
Opt Lett ; 39(9): 2534-6, 2014 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-24784038

RESUMO

An optical frequency comb based on Yb:ring fiber laser was demonstrated. This is the first time, to our knowledge, f(ceo) has been generated directly from the oscillator without further amplifications above 500 MHz repetition rate. The signal-to-noise ratio of the offset frequency was above 40 dB at 300 kHz resolution bandwidth, which supports easy stabilization. The offset frequency was stabilized for more than 6 h in an open air environment without temperature control. The stabilized repetition rate has an in-loop tracking stability of 4.46×10(-13)/τ(1/2).

10.
Opt Express ; 21(4): 4703-8, 2013 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-23482002

RESUMO

The octave-spanning spectrum was generated in a tellurite glass based microstructured fiber pumped by a 528 MHz repetition rate Yb:fiber ring laser without amplification. The laser achieved 40% output optical-to-optical efficiency with the output power of 410 mW. By adjusting the grating pair in the cavity, this oscillator can work at different cavity dispersion regimes with the shortest dechirped pulse width of 46 fs. The output pulses were then launched into a high-nonlinearity tellurite fiber, which has the zero-dispersion wavelength at ~1 µm. The high nonlinearity coefficient (1348 km⁻¹W⁻¹) and the matched zero-dispersion wavelength with pump laser enable the octave-spanning supercontinuum generated from 750 nm to 1700 nm with the coupled pulse energy above 10 pJ.


Assuntos
Tecnologia de Fibra Óptica/instrumentação , Lasers , Processamento de Sinais Assistido por Computador/instrumentação , Telecomunicações/instrumentação , Telúrio/química , Desenho de Equipamento , Análise de Falha de Equipamento , Miniaturização
11.
Opt Lett ; 38(4): 443-5, 2013 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-23455096

RESUMO

We report octave-spanning spectrum generated in a tapered silica photonic crystal fiber by a mode-locked Yb:fiber ring laser at a repetition rate as high as 528 MHz. The output pulses from this laser were compressed to 62 fs. By controlling the hole expansion and core diameter, a silica PCF was tapered to 20 cm with an optimal d/Λ ratio of 0.6. Pulses with the energy of 280 pJ and the peak power of 4.5 kW were injected into the tapered fiber and the pulse spectrum was expanded from 500 to 1600 nm at the level of -30 dB.

12.
Opt Lett ; 38(3): 314-6, 2013 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-23381422

RESUMO

We report a compact Yb:fiber ring laser operated at 750 MHz. The average output power is 210 mW at a pump power of 1.8 W. The dechirped pulse width is 68 fs.

13.
Genet Mol Biol ; 36(1): 140-7, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23569421

RESUMO

Intracellular fatty acid-binding proteins (FABPs) are multifunctional cytosolic lipid-binding proteins found in vertebrates and invertebrates. In this work, we used RACE to obtain a full-length cDNA of Sp-FABP from the mud crab Scylla paramamosain. The open reading frame of the full length cDNA (886 bp) encoded a 136 amino acid polypeptide that showed high homology with related genes from other species. Real-time quantitative PCR identified variable levels of Sp-FABP transcripts in epidermis, eyestalk, gill, heart, hemocytes, hepatopancreas, muscle, ovary, stomach and thoracic ganglia. In ovaries, Sp-FABP expression increased gradually from stage I to stage IV of development and decreased in stage V. Sp-FABP transcripts in the hepatopancreas and hemocytes were up-regulated after a bacterial challenge with Vibrio alginnolyficus. These results suggest that Sp-FABP may be involved in the growth, reproduction and immunity of the mud crab.

14.
Opt Express ; 20(14): 16017-22, 2012 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-22772291

RESUMO

We present the characterization of the carrier envelope offset frequency of 490 MHz femtosecond Yb-fiber ring laser. After amplification and compression, 1.7 W 90 fs pulses were produced for octave-span-spectrum generation from 600 nm to 1300 nm. More than 30 dB S/N ratio carrier envelope offset frequency signal was measured through a quasi-common-path interferometer.

15.
Water Sci Technol ; 65(1): 30-7, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22173405

RESUMO

An ecophysiological experiment was conducted to examine the biochemical effects of acidified seawater containing elevated concentration of CO(2) (C(CO2) 0.08, 0.20, 0.50 and 1.00%) on the copepod Centropages tenuiremis. AchE, ATPase, SOD, GPx, GST, GSH level and GSH/GSSG ratio of the copepod were analyzed. The results showed that elevated C(CO2) and the duration of culture time significantly influenced several biochemical indices in C. tenuiremis (ATPase, GPx, GST, GSH and SOD). Furthermore, the principal component analysis results indicated that 72.32% of the overall variance was explained by the first three principal components (GPx, SOD and GSH). Changes in GPx and GSH levels may play a significant role in the antioxidant defense of copepods against seawater acidification. The long-term response of copepods to seawater acidification and the synergistic effects of acidification with other environmental factors, such as temperature, salinity and trace metal need further investigation.


Assuntos
Poluentes Atmosféricos/química , Dióxido de Carbono/química , Copépodes/metabolismo , Acetilcolinesterase/metabolismo , Adenosina Trifosfatases/metabolismo , Animais , Meio Ambiente , Glutationa/metabolismo , Dissulfeto de Glutationa/metabolismo , Glutationa Peroxidase/metabolismo , Glutationa Transferase/metabolismo , Concentração de Íons de Hidrogênio , Análise de Componente Principal , Água do Mar/química , Superóxido Dismutase/metabolismo
16.
Front Pharmacol ; 13: 1015045, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36467075

RESUMO

Background: Insulin secretory agents are commonly used to treat type 2 diabetes. However, traditional insulin secretory agents such as sulfonylureas and glinides have side effects of hypoglycemia. In recent years, researchers have discovered that berberine can inhibit the voltage-gated k+ channels of pancreatic ß cell membrane and promote insulin secretion without causing hypoglycemia, because the glucose-lowering effects of berberine are only under hyperglycemic conditions or in a high-glucose-dependent manner. In order to shed light on the glucose-lowing effects of berberine in type 2 diabetes with different baseline fasting plasma glucose (FPG) and glycosylated hemoglobin (HbA1c), we conducted a meta-analysis of randomized controlled trials. Methods: We searched eight databases, which included PubMed, EMBASE, Web of Science, the Cochrane Library, and the Chinese databases such as Sino-Med, China National Knowledge Infrastructure (CNKI), Wanfang Database, and VIP Database for Chinese Technical Periodicals, for randomized controlled trials, with berberine as the intervention and patients with type 2 diabetes mellitus as subjects, published up until November 2021. We analyzed the glucose-lowing effects of berberine, including its effects on FPG, HbA1c and 2-h plasma blood glucose (2hPBG), by calculating weighted mean differences (WMD) and 95% confidence interval (CI). To assess the safety of berberine, we analyzed the incidence of total adverse events and hypoglycemia by calculating relative risk (RR) and 95% CI. Results: Thirty-seven studies involving 3,048 patients were included in the meta-analysis. The results showed that berberine could reduce FPG (WMD = -0.82 mmol/L, 95% CI (-0.95, -0.70)), HbA1c (WMD = -0.63%, 95% CI (-0.72, -0.53)), and 2hPBG (WMD = -1.16 mmol/L, 95% CI (-1.36, -0.96)), with all results being statistically significant. Subgroup analyses revealed that the glucose-lowering effect of berberine was associated with baseline mean FPG and HbA1c in type 2 diabetes. In addition, berberine alone or in combination with oral hypoglycemic agents (OHAs) in the treatment of T2DM did not significantly increase the incidence of total adverse events (RR = 0.73, 95% CI (0.55, 0.97), p = 0.03) and the risk of hypoglycemia (RR = 0.48, 95% CI (0.21, 1.08), p = 0.08). Conclusion: Berberine has a glucose-lowering effect, which is related to the baseline FPG and HbA1c levels of patients. Treatment with berberine may be safe since it does not increase the incidence of total adverse events and the risk of hypoglycemia. Systematic Review Registration: https://www.crd.york.ac.uk/prospero/display_record.php?RecordID=292975, identifier CRD42021292975.

17.
Wei Sheng Wu Xue Bao ; 51(8): 1113-8, 2011 Aug.
Artigo em Zh | MEDLINE | ID: mdl-22097777

RESUMO

OBJECTIVE: In order to find the best extraction method for proteins of Alexandrium tamarense for two-dimensional electrophoresis (2-DE) analysis. METHODS: Three methods for extracting proteins from A. tamarense were compared, including trihydroxymethyl aminomethane (Tris-HCl ) buffer extraction, trichloroacetic acid (TCA)/acetone precipitation and lysis buffer extraction. Alga was cultivated in normal f/2 media (control) and supplemented with algicidal substances. Proteins obtained using the best extraction method were separated with 2-DE. Protein-expression differences were identified using matrix-assisted laser desorption/ionization-time of flight ( MALDI-TOF) mass spectrometry (MS). RESULTS: Among the three protein extraction methods, lysis buffer extraction shows the best detection of the number and quality of protein spots with a clear background. Then, the lysis buffer extraction method was successfully applied to profiling protein expression in algicidal substances stress conditions and 14 differential expression proteins were identified using MALDI-TOF/MS. CONCLUSION: Lysis buffer extraction was the most effective protein extraction method for Alexandrium tamarense.


Assuntos
Dinoflagellida/química , Eletroforese em Gel Bidimensional/métodos , Proteômica/métodos , Proteínas de Protozoários/isolamento & purificação
18.
Dev Comp Immunol ; 120: 104050, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33631272

RESUMO

B-type allatostatins (AST-B) are neuropeptides that have important physiological roles in arthropods, they have also been identified in a number of crustacean species. Recent research on neuroendocrine-immune (NEI) regulatory system in invertebrates has exploded, it reveals that the NEI network plays an indispensable role in optimizing the immune response and maintaining homeostasis. Herein, mud crab Scylla paramamosain provides a primitive and ancient model to study crosstalk between the neuroendocrine and immune systems. In this study, qRT-PCR analysis showed that the nervous system was the main production site for Sp-AST-B mRNA in S. paramamosain, while its receptor gene (Sp-AST-BR) mRNA could be detected in all the analyzed tissues including hemocytes. This reveals that AST-B might act as a pleiotropic neuropeptide. In situ hybridization further confirmed that granular cells of hemocyte subpopulations express Sp-AST-BR. Time-course analysis revealed that bacteria-analog LPS or virus-analog Poly (I:C) challenge significantly induced Sp-AST-B expression in the thoracic ganglion, and the expression of Sp-AST-BR in hemocytes were also positively changed. Furthermore, mud crabs treated with a synthetic AST-B peptide significantly increased the mRNA levels of AST-BR, nuclear factor-κB (NF-κB) transcription factor (Dorsal and Relish), pro-inflammatory cytokine (IL-16) and immune-effector molecules, and also dramatically enhanced the nitric oxide (NO) production and phagocytic activity in hemocytes. Meanwhile dsRNA-mediated knockdown of Sp-AST-B remarkably suppressed the NO concentrations, phagocytic activity and the expression of immune related genes, resulting in markedly impaired ability of crabs to inhibit bacterial proliferation in vivo. Combined, these data demonstrate that AST-B induced innate immune in the mud crab.


Assuntos
Proteínas de Artrópodes/metabolismo , Braquiúros/imunologia , Hemócitos/imunologia , Imunidade Inata , Neuropeptídeos/metabolismo , Animais , Proteínas de Artrópodes/genética , Braquiúros/metabolismo , Braquiúros/microbiologia , Clonagem Molecular , Resistência à Doença , Regulação da Expressão Gênica , Técnicas de Silenciamento de Genes , Hemócitos/metabolismo , Neuropeptídeos/genética , Fagocitose , Poli I-C , Vibrio parahaemolyticus/imunologia
19.
Ecotoxicology ; 19(2): 273-84, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19821026

RESUMO

Tigriopus japonicus Mori has been recognized as a good model for toxicological testing of marine pollutants. Recently, a large number of genes have been identified from this copepod, and their mRNA expression has been studied independently against exposure to marine pollutants; however, biochemical-response information is relatively scarce. The response of T. japonicus to nickel (Ni) additions was examined under laboratory-controlled conditions in 12 days exposure. Superoxide dismutase (SOD), glutathione peroxidase (GPx), glutathione-S-transferase (GST), acetylcholinesterase (AchE), reduced glutathione (GSH), the ratio of reduced to oxidized glutathione (GSH/GSSG) and metallothionein (MT) were analyzed for Ni treatments (0, 0.125, 0.25, 0.75 and 3.0 mg/L) after 1, 4, 7 and 12 days. The thiobarbituric reactive species assay was used to evaluate lipid peroxidation (LPO) level in copepods after exposure. The results showed that Ni remarkably affected the biochemical parameters (SOD, GPx, GST, GSH, and GSH/GSSG) after certain exposure durations. However, the copepod's LPO level was significantly decreased under metal treatments after exposure, hinting that the factors involved in LPO might not significantly depend on the operations and functions in the antioxidant system. Ni exhibited the neurotoxicity to copepods, because its use obviously elevated AchE activity. During exposure, Ni initially displayed an inhibition effect but induced MT synthesis in T. japonicus by day 12, probably being responsible for metal detoxification. Thus, Ni had intervened in the detoxification process and antioxidant system of this copepod, and it could be used as a suitable bioindicator of Ni exposure via measuring SOD, GPx, GST, and MT as biomarkers.


Assuntos
Copépodes/efeitos dos fármacos , Copépodes/metabolismo , Peroxidação de Lipídeos/efeitos dos fármacos , Níquel/toxicidade , Estresse Oxidativo/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade , Acetilcolinesterase/metabolismo , Animais , Biomarcadores/metabolismo , Copépodes/enzimologia , Relação Dose-Resposta a Droga , Geografia , Glutationa/metabolismo , Glutationa Peroxidase/metabolismo , Glutationa Transferase/metabolismo , Peroxidação de Lipídeos/fisiologia , Metalotioneína/metabolismo , Níquel/metabolismo , Estresse Oxidativo/fisiologia , Superóxido Dismutase/metabolismo , Substâncias Reativas com Ácido Tiobarbitúrico/metabolismo , Fatores de Tempo , Poluentes Químicos da Água/metabolismo
20.
Ecotoxicology ; 19(5): 911-6, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20182790

RESUMO

Lethal and sublethal toxicity of Nickel (Ni) to three marine copepods Tigriopus japonicus, Apocyclops borneoensis and Acartia pacifica was investigated. The 48-h LC50 values were 17.70, 13.05 and 2.36 mg l(-1) Ni, respectively. A. pacifica was found to be the most sensitive to Ni in acute exposure tests. In order to assess sublethal effects of Ni on copepod reproduction, the test organisms were exposed to four nominal Ni concentrations 0, 10, 100, 1000 microg l(-1) Ni. The results indicated that offspring production of T. japonicus and A. borneoensis was significantly reduced after exposure to 10 microg l(-1) Ni. Whereas egg production and egg hatching success of A. pacifica were significantly reduced at 100 and 10 microg l(-1) Ni, respectively. Exposure of copepods to the highest Ni concentration caused a severely reduced nauplii production from T. japonicus, A. borneoensis and A. pacifica by 87.8, 56.9 and 65.8%, respectively, and a significantly reduced egg production of A. pacifica by 74.4%. These results show that Ni excess in the coastal environment can have detrimental effects on reproduction of copepods.


Assuntos
Copépodes , Níquel/toxicidade , Reprodução/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade , Animais , Relação Dose-Resposta a Droga , Feminino , Dose Letal Mediana , Níquel/administração & dosagem , Especificidade da Espécie , Poluentes Químicos da Água/administração & dosagem
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