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1.
Eat Weight Disord ; 26(2): 703-707, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32146595

RESUMO

PURPOSE: This cross-sectional study aimed at comparing the quality of life (Qol), the prevalence of psychiatric diagnosis and pharmacological treatment in 104 candidates to bariatric surgery according to the degree of obesity (class 2 vs. class ≥ 3 obesity). METHODS: All surgical candidates underwent a detailed psychiatric interview based on DSM-5 criteria, including sociodemographic, clinical, psychological and psychiatric data. Participants completed the Binge Eating Scale (BES) and the 12-Item Short Form Health Survey (SF-12). RESULTS: Overall, bariatric candidates reported a significant impairment in the physical (PCS 38.8 [95% CI 36.2-41.5]) and mental (MCS 42.2 [95% CI 40.4-43.9]) components of Qol compared to population norms (p < 0.001 for both). Subjects with class 2 obesity scored significantly lower in the MCS compared to those with class 3 (38.7 (8.1) vs. 43.6 (8.4), p = 0.008). No other statistically significant differences were found between the two groups in terms of sociodemographic and clinical variables. CONCLUSION: These data support the usefulness of Qol assessment in bariatric candidates as a sensible screening parameter, especially in patients with lower BMI, in whom MCS could identify the need for early psychosocial intervention. LEVEL OF EVIDENCE: Level III, case-control analytic study.


Assuntos
Cirurgia Bariátrica , Transtornos Mentais , Obesidade Mórbida , Índice de Massa Corporal , Estudos Transversais , Humanos , Qualidade de Vida
2.
J Appl Microbiol ; 126(3): 780-795, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30586234

RESUMO

AIMS: The Algerian coastline is exposed to several types of pollution, including hydrocarbons. The aim of this work was to isolate oil-degrading bacteria and to explore the intrinsic bioremediation potential of part of its contaminated harbour. METHODS AND RESULTS: A collection of 119 strains, capable to grow on mineral medium supplemented with hydrocarbons, were obtained from polluted sediment and seawater collected from Sidi Fredj harbour (Algiers). Twenty-three strains were selected for further studies. Sequencing of the 16S rRNA gene showed that most isolates belong to genera of hydrocarbonoclastic bacteria (Alcanivorax), generalist hydrocarbons degraders (Marinobacter, Pseudomonas, Gordonia, Halomonas, Erythrobacter and Brevibacterium) and other bacteria not known as hydrocarbon degraders (Xanthomarina) but were able to degrade hydrocarbons. Strains related to Marinobacter and Alcanivorax were frequently isolated from our samples and resulted the most effective in degrading crude oil. Screening of catabolic genes alkB and xylA revealed the presence of alkB gene in several bacterial strains; one isolate harboured both catabolic genes while other isolates carried none of the studied genes. However, they grew in the presence of crude oil implying the existence of other biodegradation pathways. CONCLUSIONS: The samples of seawater and sediment from the Algerian coast contain high level of hydrocarbon-degrading bacteria that could be interesting and useful for future bioremediation purposes. SIGNIFICANCE AND IMPACT OF THE STUDY: This investigation demonstrates the diversity of hydrocarbon-degrading bacteria from a marine-contaminated area in Algeria, and their variable biodegradation abilities.


Assuntos
Bactérias/isolamento & purificação , Bactérias/metabolismo , Petróleo/metabolismo , Água do Mar/microbiologia , Argélia , Bactérias/classificação , Bactérias/genética , Biodegradação Ambiental , Biotecnologia , Hidrocarbonetos/metabolismo , Filogenia , RNA Ribossômico 16S/genética
3.
J Appl Microbiol ; 127(3): 618-629, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30848509

RESUMO

The aims of this study were: (i) the characterization of the structure of the indigenous microbial community associated with the sediments under study; (ii) the isolation and characterization of microbial consortia able to degrade the aged hydrocarbons contaminating the sediments, and (iii) the assessment of related biodegradation capability of selected consortia. Samples of surface sediments were collected in Priolo Gargallo harbour (Sicily, Italy). The samples were analysed for physical, chemical (GC-FID analysis) and microbiological characteristics (qualitative (16S rDNA clone library) and quantitative (DAPI, CFU and MPN count) analysis). The sediment samples were used for the selection of two microbial consortia (indicated as PSO and PSM) with high biodegradation capacity for crude oil (∼95%) and PAHs (∼63%) respectively. Genetic analysis showed that Alcanivorax and Cycloclasticus were the dominant genera in both the PSO and PSM consortia. Oil-polluted environments naturally develop an elevated biorecovery potential. The presence of a highly specialized microbial flora (adapted to support the contamination) and their stimulation through favourable induced conditions provides a promising recovery strategy. The chance to identify and select indigenous bacteria and/or consortia with a high biodegradation capacity is fundamental for the development and optimization of bioaugmentation strategies especially for those concerning in situ applications.


Assuntos
Bactérias/metabolismo , Sedimentos Geológicos/microbiologia , Hidrocarbonetos/metabolismo , Consórcios Microbianos , Poluentes Químicos da Água/metabolismo , Bactérias/isolamento & purificação , Biodegradação Ambiental , Gammaproteobacteria/isolamento & purificação , Sedimentos Geológicos/química , Itália , Petróleo/metabolismo , Poluição por Petróleo , Hidrocarbonetos Policíclicos Aromáticos/metabolismo
4.
J Environ Manage ; 223: 749-757, 2018 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-29986322

RESUMO

Many recent studies have focused their attention on the physiological stress experienced by marine organisms in measuring ecotoxicological responses. Here we suggest a new approach for investigating the effects of an anthropogenic pollutant on Life-History (LH) traits of marine organisms, to provide stakeholders and policy makers an effective tool to evaluate the best environmental recovery strategies and plans. A Dynamic Energy Budget (DEB), coupled with a biophysical model was used to predict the effects of a six-month oil spill on Mytilus galloprovincialis' LH traits and to test two potential recovery strategies in the central Mediterranean Sea. Oxygen consumption rates were used to check for increasing energetic maintenance costs [pM] respectively in oil-polluted system treatments (∼76.2%) and polluted systems with physical (nano-bubbles ∼32.6%) or chemical treatment (dispersant ∼18.4%). Our model outputs highlighted a higher growth reduction of intertidal compared to subtidal populations and contextually an effect on the reproductive output and on the maturation time of this latter. The models also enabled an estimation of the timing of the disturbance affecting both the intertidal and subtidal populations' growth and reproduction. Interestingly, results led to the identification of the chemical dispersant as being the best remediation technique in contexts of oil spill contamination.


Assuntos
Mytilus , Poluição por Petróleo , Poluentes Químicos da Água , Animais , Organismos Aquáticos , Monitoramento Ambiental , Mar Mediterrâneo , Reprodução
5.
Phys Rev Lett ; 111(8): 085002, 2013 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-24010447

RESUMO

We report the first nonlinear three-dimensional magnetohydrodynamic (MHD) numerical simulations of the reversed-field pinch (RFP) that exhibit a systematic repetition of quasisingle helicity states with the same dominant mode in between reconnection events. This distinctive feature of experimental self-organized helical RFP plasmas is reproduced in MHD simulations at low dissipation by allowing a helical modulation of the plasma magnetic boundary similar to the experimental one. Realistic mode amplitudes and magnetic topology are also found.

6.
Phys Rev Lett ; 105(19): 195001, 2010 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-21231172

RESUMO

In the reversed field pinch RFX-mod strong electron temperature gradients develop when the single-helical-axis regime is achieved. Gyrokinetic calculations show that in the region of the strong temperature gradients microtearing instabilities are the dominant turbulent mechanism acting on the ion Larmor radius scale. The quasilinear evaluation of the electron thermal conductivity is in good agreement with the experimental estimates.

7.
Environ Int ; 143: 105999, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32763632

RESUMO

Plastic debris has been identified as a potential threat to Antarctic marine ecosystems, however, the impact of nanoplastics (<1 µm) is currently unexplored. Antarctic krill (Euphausia superba) is a keystone species of Southern Ocean pelagic ecosystems, which plays a central role in the Antarctic food webs and carbon (C) cycle. Krill has been shown to rapidly fragment microplastic beads through the digestive system, releasing nanoplastics with unknown toxicological effects. Here we exposed krill juveniles to carboxylic (COOH, anionic) and amino- (NH2, cationic) polystyrene nanoparticles (PS NPs) and we investigated lethal and sub-lethal endpoints after 48 h. The analysis of PS NP suspensions in Antarctic sea water (SW) media showed that PS-COOH formed large agglomerates (1043 ± 121 nm), while PS-NH2 kept their nominal size (56.8 ± 3 nm) during the exposure time. After 48 h, no mortality was found but increase in exuviae production (12.6 ± 1.3%) and reduced swimming activity were observed in juveniles exposed to PS-NH2. The microbial community composition in SW supports the release of krill moults upon PS NP exposure and stimulates further research on the pivotal role of krill in shaping Southern Ocean bacterial assemblages. The presence of fluorescent signal in krill faecal pellets (FPs) confirmed the waterborne ingestion and egestion of PS-COOH at 48 h of exposure. Changes in FP structure and properties were also associated to the incorporation of PS NPs regardless of their surface charge. The effects of PS NPs on krill FP properties were compared to Control 0 h as a reference for full FPs (plastic vs food) and Control 48 h as a reference for more empty-like FPs (plastic vs lack of food). Exposure to PS NPs led to a FP sinking rate comparable to Control 48 h, but significantly lower than Control 0 h (58.40 ± 23.60 m/d and 51.23 ± 28.60 m/d for PS-COOH and PS-NH2; 168.80 ± 74.58 m/d for Control 0 h). Considering the important role played by krill in the food web and C export in the Southern Ocean, the present study provides cues about the potential impact of nanoplastics on Antarctic pelagic ecosystems and their biogeochemical cycles.


Assuntos
Euphausiacea , Animais , Regiões Antárticas , Ecossistema , Microplásticos , Muda , Plásticos
8.
Sci Total Environ ; 690: 140-150, 2019 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-31284188

RESUMO

The work was addressed to study the sensitivity of the enzyme carbonic anhydrase (CA) to chemical pollution in the hepatopancreas of the bioindicator organism Mytilus galloprovincialis in the context of a multimarker approach in view of ecotoxicological biomonitoring and assessment application. The study was carried out by means of a transplanting experiment in the field, using caged organisms from an initial population exposed in the field in two areas of interest: Augusta-Melilli-Priolo, an heavy polluted industrial site (eastern Sicily, Italy), and Brucoli (eastern Sicily, Italy) an area not affected by any contamination and selected as a reference site. Mussels in Augusta presented a significant increase in the digestive gland CA activity and gene expression compared to the animals caged in the control site of Brucoli. The CA response in animals from the polluted site was paralleled by proliferation/increase in the size of lysosomes, as assessed by Lysosensor green charged cells, induction of metallothionein, up-regulation of hif-α (hypoxia-inducible factor), metabolic changes associated with protein metabolism, and changes in the condition factor. Biological responses data were integrated with information about sediment chemical analysis and metal residue concentration in animal soft tissues. In conclusion, obtained results highlighted the induction of CAs in the hepatopancreas of Mytilus galloprovincialis following to pollution exposure, and demonstrated its suitability to be integrated into a multimarker approach for the detection and characterization of the stress status induced by pollution exposure in this bioindicator organism.


Assuntos
Anidrases Carbônicas/metabolismo , Monitoramento Ambiental/métodos , Mytilus/metabolismo , Poluentes Químicos da Água/toxicidade , Animais , Biomarcadores/metabolismo , Sicília
9.
Water Res ; 157: 381-395, 2019 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-30974287

RESUMO

Marine sediments represent an important sink of harmful petroleum hydrocarbons after an accidental oil spill. Electrobioremediation techniques, which combine electrokinetic transport and biodegradation processes, represent an emerging technological platform for a sustainable remediation of contaminated sediments. Here, we describe the results of a long-term mesocosm-scale electrobioremediation experiment for the treatment of marine sediments contaminated by crude oil. A dimensionally stable anode and a stainless-steel mesh cathode were employed to drive seawater electrolysis at a fixed current density of 11 A/m2. This approach allowed establishing conditions conducive to contaminants biodegradation, as confirmed by the enrichment of Alcanivorax borkumensis cells harboring the alkB-gene and other aerobic hydrocarbonoclastic bacteria. Oil chemistry analyses indicated that aromatic hydrocarbons were primarily removed from the sediment via electroosmosis and low molecular weight alkanes (nC6 to nC10) via biodegradation.


Assuntos
Poluição por Petróleo , Petróleo , Biodegradação Ambiental , Sedimentos Geológicos , Hidrocarbonetos , Água do Mar
10.
J Appl Microbiol ; 105(5): 1694-702, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19149767

RESUMO

AIMS: In this study, we evaluated the removal efficiency of fuel hydrocarbons from a jet fuel contaminated area using bioaugmentation treatment in biopile. METHODS AND RESULTS: The hydrocarbon analysis of the sample revealed total hydrocarbons mainly constituted by benzene, toluene, ethylbenzene, xylenes (BTEX) and heavy aliphatic hydrocarbons. Enrichments of soil sample were performed with BTEX, pristane and fuel JP-5, respectively, selected hydrocarbon-degrading strains, namely Acinetobacter sp., Pseudomonas sp. and Rhodococcus sp. Three hundred litres of culture containing 10(8) cell ml(-1) of each strain and nutrients sprayed on the biopile allowed a removal of 90% of total hydrocarbons in 15 days. Bioremediation process was monitored by observation of the respiration rate and the bacterial abundance and GC-MS analysis. CONCLUSIONS: The efficiency of the treatment in the biopile was considerable. The assessment of microbial activity during the experiment is necessary for interventions targeted to improve environmental parameters such as humidity, temperature, pH and nutrients for optimization of the bioremediation process. SIGNIFICANCE AND IMPACT OF THE STUDY: A better knowledge of microbial successions at oil-polluted sites is essential for environmental bioremediation. Data obtained in biopile study improve our understanding of processes occurring during oil pollution.


Assuntos
Bactérias/metabolismo , Recuperação e Remediação Ambiental/métodos , Hidrocarbonetos/metabolismo , Microbiologia do Solo , Poluentes do Solo/metabolismo , Bactérias/crescimento & desenvolvimento , Benzeno/metabolismo , Derivados de Benzeno/metabolismo , Biodegradação Ambiental , Contagem de Colônia Microbiana/métodos , Respiração , Tolueno/metabolismo , Xilenos/metabolismo
11.
Life Sci ; 81(10): 779-93, 2007 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-17707439

RESUMO

Nitric oxide (NO) participates in the control of contractility and heart rate, limits cardiac remodeling after an infarction and contributes to the protective effect of ischemic pre- and postconditioning. Low concentrations of NO, with production of small amounts of cGMP, inhibit phosphodiesterase III, thus preventing the hydrolysis of cAMP. The subsequent activation of a protein-kinase A causes the opening of sarcolemmal voltage-operated and sarcoplasmic ryanodin receptor Ca(2+) channels, thus increasing myocardial contractility. High concentrations of NO induce the production of larger amounts of cGMP which are responsible for a cardiodepression in response to an activation of protein kinase G (PKG) with blockade of sarcolemmal Ca(2+) channels. NO is also involved in reduced contractile response to adrenergic stimulation in heart failure. A reduction of heart rate is an evident effect of NO-synthase (NOS) inhibition. It is noteworthy that the direct effect of NOS inhibition can be altered if baroreceptors are stimulated by increases in blood pressure. Finally, NO can limit the deleterious effects of cardiac remodeling after myocardial infarction possibly via the cGMP pathway. The protective effect of NO is mainly mediated by the guanylyl cyclase-cGMP pathway resulting in activation of PKG with opening of mitochondrial ATP-sensitive potassium channels and inhibition of the mitochondrial permeability transition pores. NO acting on heart is produced by vascular and endocardial endothelial NOS, as well as neuronal and inducible synthases. In particular, while in the basal control of contractility, endothelial synthase has a predominant role, the inducible isoform is mainly responsible for the cardiodepression in septic shock.


Assuntos
Frequência Cardíaca/fisiologia , Coração/fisiologia , Precondicionamento Isquêmico Miocárdico , Contração Miocárdica/fisiologia , Óxido Nítrico/fisiologia , Remodelação Ventricular/fisiologia , Animais , Modelos Animais de Doenças , Humanos , Traumatismo por Reperfusão/prevenção & controle
12.
G Ital Med Lav Ergon ; 28(2): 226-8, 2006.
Artigo em Italiano | MEDLINE | ID: mdl-16805480

RESUMO

Accidental aspiration of fuel in fire eaters can cause an acute chemical pneumonitis known as 'fire-eater's pneumonia". We report a case in a 29 year-old fire-eater. Six hours after aspiration of kerosene, he developed fever up to 39,5 degrees C, dyspnea, cough and chest pain. Chest radiograph showed infiltrates in the middle and lower parts of the lungs and left pleural effusion. He was treated with an antibiotic and antipiretic therapy and then with corticosteroids. The acute stage lasted four weeks and the patient recovered without sequelae within 3 months. Hazard related to main fuels used for fire eating is discussed.


Assuntos
Querosene/efeitos adversos , Doenças Profissionais/induzido quimicamente , Pneumonia/induzido quimicamente , Doença Aguda , Adulto , Incêndios , Humanos , Masculino
13.
Mar Pollut Bull ; 107(1): 107-117, 2016 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-27158046

RESUMO

A bacterial consortium composed by four metagenomic clones and Bacillus subtilis strain CBMAI 707, all derived from petroleum reservoirs, was entrapped in chitosan beads and evaluated regarding hydrocarbon degradation capability. Experiments were carried out in mesocosm scale (3000L) with seawater artificially polluted with crude oil. At different time intervals, mesocosms were sampled and subjected to GC-FID and microbiological analyses, as total and heterotrophic culturable bacterial abundance (DAPI and CFU count), biological oxygen demand (BOD) and taxonomic diversity (massive sequencing of 16S rRNA genes). The results obtained showed that degradation of n-alkane hydrocarbons was similar between both treatments. However, aromatic compound degradation was more efficient in bioaugmentation treatment, with biodegradation percentages reaching up to 99% in 30days. Community dynamics was different between treatments and the consortium used in the bioaugmentation treatment contributed to a significant increase in aromatic hydrocarbon degradation.


Assuntos
Bactérias/metabolismo , Consórcios Microbianos , Petróleo/metabolismo , Biodegradação Ambiental , Células Imobilizadas/metabolismo , Quitosana , Hidrocarbonetos/metabolismo , RNA Ribossômico 16S/genética
14.
Mar Pollut Bull ; 105(1): 125-30, 2016 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-26912198

RESUMO

The present study is focused on assessing the growth and hydrocarbon-degrading capability of the psychrophilic strain Oleispira antarctica RB-8(T). This study considered six hydrocarbon mixtures that were tested for 22days at two different cultivation temperatures (4 and 15°C). During the incubation period, six sub-aliquots of each culture at different times were processed for total bacterial abundance and GC-FID (gas chromatography-flame ionization detection) hydrocarbon analysis. Results from DNA extraction and DAPI (4',6-diamidino-2-phenylindole) staining showed a linear increase during the first 18days of the experiment in almost all the substrates used; both techniques showed a good match, but the difference in values obtained was approximately one order of magnitude. GC-FID results revealed a substantial hydrocarbon degradation rate in almost all hydrocarbon sources and in particular at 15°C rather than 4°C (for commercial oil engine, oily waste, fuel jet, and crude oil). A more efficient degradation was observed in cultures grown with diesel and bilge water at 4°C.


Assuntos
Bactérias/metabolismo , Biodegradação Ambiental , Hidrocarbonetos/metabolismo , Poluentes Químicos da Água/metabolismo , Bactérias/classificação , Bactérias/genética , Óleos , Petróleo/metabolismo
15.
Phys Rev Lett ; 85(18): 3838-41, 2000 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-11041940

RESUMO

A scaling approach to the simplest viscoresistive MHD model reveals that the Prandtl number acts only through the inertia term. When this term is negligible the dynamics is ruled by the Hartmann number H only. This occurs for the reversed field pinch dynamics as seen by numerical simulation of the model. When H is large the system is in a multiple helicity state. In the vicinity of H = 2500 the system displays temporal intermittency with laminar phases of quasi-single-helicity (SH) type. For lower H's two basins of SH are shown to coexist. SH regimes are of interest because of their nonchaotic magnetic field.

16.
Phys Rev Lett ; 85(8): 1662-5, 2000 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-10970583

RESUMO

The reversed field pinch (RFP) is a configuration for plasma magnetic confinement. It has been traditionally viewed as dominated by a bath of MHD instabilities producing magnetic chaos and high energy transport. We report experimental results which go beyond this view. They show a decrease of magnetic chaos and the formation of a coherent helical structure in the plasma, whose imaging and temperature profile are provided for the first time. These quasi-single-helicity states are observed both transiently and in stationary conditions. The last case is consistent with a theoretically predicted bifurcation. Our results set a new frame for improving confinement in high current nonchaotic RFP's.

17.
Scanning ; 24(6): 274-83, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-12507381

RESUMO

The morphologic and structural variations suffered by cells of a population of Pseudomonas aeruginosa ATCC 27853 under stress conditions were investigated by using scanning near-field optical microscopy. The analysis of the images, supported by microbiological data, showed that the bacteria evolved from the initial distribution of rod-shaped cells of standard size to a population with structural and morphologic modifications. The detection of variations in the optical reflectivity over a subwavelength scale (< or = 100 nm), combined with the concurrently acquired topographical signal, allowed the visualisation of rod-shaped bacteria going towards a lytic process and entire "U"-shaped cells. In the latter cells, which derived from a morphology refolding of rod bacteria, cellular matter seemed to rearrange itself to attain a coccoid stress resistant form, responsible for the residual viability of the population.


Assuntos
Pseudomonas aeruginosa/fisiologia , Pseudomonas aeruginosa/ultraestrutura , Biomassa , Contagem de Colônia Microbiana , Meios de Cultura , Microscopia Eletrônica de Varredura/métodos , Microscopia de Contraste de Fase , Pseudomonas aeruginosa/crescimento & desenvolvimento
18.
Minerva Chir ; 45(19): 1249-51, 1990 Oct 15.
Artigo em Italiano | MEDLINE | ID: mdl-2074948

RESUMO

A case of postoperative cholecystitis in a 64 years old man is reported. This is a nosological entity characterized by gallbladder distension without any patent obstacle in the cystic duct and constancy of necrosis involving all the parietal layers. Clinical signs and symptoms are aspecific. Mortality rate is high and diagnosis has to be done quickly because the gallbladder necrosis makes cholecystectomy compulsory on such patients.


Assuntos
Colecistite/cirurgia , Complicações Pós-Operatórias/cirurgia , Doença Aguda , Colecistectomia , Colecistite/etiologia , Colecistite/patologia , Vesícula Biliar/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Necrose/patologia , Necrose/cirurgia , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/patologia
19.
Artigo em Inglês | MEDLINE | ID: mdl-21285922

RESUMO

Ahead of Print article withdrawn by publisher.

20.
J Physiol Pharmacol ; 61(1): 21-7, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20228411

RESUMO

Nitric oxide (NO) and reactive oxygen species (ROS) are double-edged swords in reperfused hearts. The effects of a NO-donor and an antioxidant compound against ischemia/reperfusion were studied. The compounds were tested separately, as a mixture and as a new hybrid molecule containing both leads. Isolated rat hearts underwent 30 min global ischemia and 2 hrs reperfusion. Compounds were infused either at 1 or 10 microM concentrations during the first 20 min of reperfusion. Hybrid was also tested in the presence of mitochondrial K(+) ATP-sensitive (mKATP) channel blockade by 5-HD (100 microM). Reduction of infarct size and recovery of left ventricular developed pressure during reperfusion were evaluated. When given at 1 microM concentration, hybrid significantly improved all indices of protection; its beneficial effects were abolished by mKATP channel blockade. At the same concentration, mixture and NO-donor alone improved recovery of left ventricular developed pressure but did not reduce infarct size; antioxidant was ineffective. When given at 10 microM concentration, antioxidant and mixture improved all parameters of protection; NO-donor and hybrid were ineffective. Our data suggest that different signaling cascades could be elicited by low and high concentrations of antioxidant compound and/or NO-donor. It is likely that a different NO-induced release of reactive oxygen species via mKATP channel activation may play a pivotal role in affecting infarct size and post-ischemic contractile recovery.


Assuntos
Antioxidantes/metabolismo , Cardiotônicos/metabolismo , Traumatismo por Reperfusão Miocárdica/prevenção & controle , Doadores de Óxido Nítrico/metabolismo , Animais , Antioxidantes/administração & dosagem , Cardiotônicos/administração & dosagem , Interações Medicamentosas/fisiologia , Quimioterapia Combinada , Lipídeos , Masculino , Traumatismo por Reperfusão Miocárdica/metabolismo , Traumatismo por Reperfusão Miocárdica/patologia , Doadores de Óxido Nítrico/administração & dosagem , Técnicas de Cultura de Órgãos , Ratos , Ratos Wistar , Solubilidade
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