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Cunha C, Fernandes M, Santos M, Ferreira M, Caiado A, Miranda P, Azevedo P, Manso M, Oliveira J, Barreira S, Féria L, Maio R. ERAS® program in the “elderly” - can we still improve even in the extremes? Clin Nutr ESPEN 2019. [DOI: 10.1016/j.clnesp.2019.03.052] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Faustino B, Oliveira J, Lopes P. Diagnostic precision of the Wisconsin Card Sorting Test in assessing cognitive deficits in substance use disorders. APPLIED NEUROPSYCHOLOGY-ADULT 2019; 28:165-172. [PMID: 31060391 DOI: 10.1080/23279095.2019.1607737] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
The Wisconsin Card Sorting Test (WCST) is a widely used neuropsychological instrument to assess executive functions related to cognitive flexibility and abstract reasoning. However, there is a lack of studies investigating the diagnostic precision of this instrument in substance use disorders. In this study, we aimed at assessing the sensitivity and specificity of the WCST in discriminating the performance of participants with substance use disorder with cognitive deficits and participants from the general population without cognitive deficits. The sample comprised three groups of participants with substance use disorders (opioid use disorder in harm reduction with methadone maintenance; opioid use disorder in treatment in a therapeutic community; alcohol use disorder in a therapeutic community) and a normative group of healthy adults. The total sample consisted of 587 participants that were assessed with cognitive tests for executive functions, general cognitive functioning, and self-reported depression. The results showed differences between groups in most WCST variables, providing evidence of discriminant validity for this test. Convergent validity was also established by weak to moderate correlations with general cognitive functioning. Cutoff points based on receiver operating characteristic (ROC) curves were calculated for the WCST variables. Overall, the WCST was sensitive to changes in cognitive flexibility and abstract reasoning that are key features of substance use disorders.
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Oliveira J, Sousa F, Coutinho F, Campos S, Castro M, Marques J, Carvalho G, Negrão L, Almeida e Sousa L, Águas F. Ultrasound accuracy in Granulosa Cell Tumors diagnosis. Australas J Ultrasound Med 2019. [DOI: 10.1002/ajum.12157] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
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Coutinho F, Oliveira J, Rodrigues A, Castro M, Carvalho M, Sousa L, Aguas F. Ultrasound Guided Ovarian Mass Biopsy in women with suspicious sonographic features. Australas J Ultrasound Med 2019. [DOI: 10.1002/ajum.12154] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
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Maia A, Oliveira J, Lajnef M, Mallet L, Tamouza R, Leboyer M, Oliveira-Maia AJ. Oxidative and nitrosative stress markers in obsessive-compulsive disorder: a systematic review and meta-analysis. Acta Psychiatr Scand 2019; 139:420-433. [PMID: 30873609 DOI: 10.1111/acps.13026] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 03/06/2019] [Indexed: 12/17/2022]
Abstract
OBJECTIVE Obsessive-compulsive disorder (OCD) is a chronic, prevalent, and highly impairing psychiatric illness. Although the pathophysiology of OCD remains unknown, pathways involved in oxidative and nitrosative stress (O&NS) have been implicated. The present study aims to systematically review the literature for quantitative evidence that patients with OCD have altered measures of blood O&NS markers. METHODS Independent random-effects meta-analyses using standardized mean differences were conducted to assess each marker separately. Additionally, data from multiple markers were pooled together in a meta-analysis for measures of oxidant activity and another for measures of antioxidant activity. RESULTS Thirteen studies met inclusion criteria, involving 433 OCD patients and 459 controls. Eleven blood O&NS markers were eligible for independent quantitative analyses. We found that, in OCD patients, the oxidant markers 8-hydroxydeoxyguanosine and malondialdehyde, and the antioxidants glutathione peroxidase and superoxide dismutase, were significantly increased while total antioxidant status, vitamin C, and vitamin E were significantly decreased, when comparing with controls. Regarding pooled meta-analyses, we found a statistically significant increase in oxidant markers, but non-significant results regarding antioxidant markers. CONCLUSIONS Our meta-analysis suggests that OCD patients have a systemic oxidative imbalance that is not adequately buffered by the antioxidant system. Additional studies are needed in order to support this association.
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Moreira LDM, Alves A, Facchin A, Oliveira J, Tsuru F, Colodetto N, Salgado M, Murara G, Facchin L. Epidemiological profile of face fractures in patients at a university hospital of Curitiba City, Brazil. Int J Oral Maxillofac Surg 2019. [DOI: 10.1016/j.ijom.2019.03.617] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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Ghareeb F, Lencart J, Oliveira J, Santos J. PV-0477 A Monte Carlo study of collimator angle dependence of extra focal dose during VMAT. Radiother Oncol 2019. [DOI: 10.1016/s0167-8140(19)30897-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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Oliveira J, Aznar M, Kirova Y, Henry A, Aljabar P, Van Herk M, Poortmans P, Gooding M. EP-2062 Feasibility of automatic detection of breast limits for auto-planning. Radiother Oncol 2019. [DOI: 10.1016/s0167-8140(19)32482-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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André A, Figueiredo J, Jordão C, Oliveira J. Ultrasound evaluation of the intima-media complex of the common carotid arteries. Eur J Public Health 2019. [DOI: 10.1093/eurpub/ckz034.097] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
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Oliveira J, Viveiros J, Patrício R, Gonçalves J, Almeida S, Silva B, Rosendo I. Gestational Diabetes: what is the clinical impact of the new recommendations? Eur J Public Health 2019. [DOI: 10.1093/eurpub/ckz035.010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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de Azevedo P, Pithon-Curi T, Moura Zagatto A, Oliveira J, Perez S. Maximal lactate steady state in Judo. Muscles Ligaments Tendons J 2019. [DOI: 10.32098/mltj.02.2014.07] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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Areia C, Barreira P, Montanha T, Oliveira J, Ribeiro F. Neuromuscular changes in football players with previous hamstring injury. Physiotherapy 2019. [DOI: 10.1016/j.physio.2018.11.105] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Simon C, Oliveira J, Fontaine X. Péritonite biliaire sur une cholécystite emphysémateuse et abcès hépatique à Clostridium perfringens. ANNALES FRANCAISES DE MEDECINE D URGENCE 2019. [DOI: 10.3166/afmu-2018-0088] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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Ayres-Pereira I, Ribeiro AI, Tenente J, Leitao C, Nunes JG, Oliveira J, Vila-Real M, Santos-Pocas MFO. [Acute parainfectious transverse myelitis with radiculitis in a child with closed spinal dysraphism]. Rev Neurol 2018; 67:461-463. [PMID: 30484279] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
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Tamouza R, Oliveira J, Etain B, Bengoufa D, Hamdani N, Manier C, Mariaselvam C, Sundaresh A, Bellivier F, Henry C, Kahn JP, Krishnamoorthy R, Charron D, Leboyer M. HLA genetics in bipolar disorder. Acta Psychiatr Scand 2018; 138:464-471. [PMID: 29869414 DOI: 10.1111/acps.12912] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 05/16/2018] [Indexed: 12/17/2022]
Abstract
OBJECTIVE Bipolar Disorder (BD) is characterized by deregulated adaptive immune processes. Recent genome-wide association studies (GWAS) implicate the major histocompatibility complex (MHC) region in BD. The present study investigates the potential influence of variations in human leukocyte antigen (HLA) on BD risk and/or clinical presentations. This may have relevance to the dysregulated inflammatory processes commonly found in BD. METHOD DNAs from 475 BD patients and 195 healthy controls (HC) were genotyped for classical HLA class I and II loci. RESULTS We found that: (i) the HLA-A*02~B*44~DRB1*07 sub-haplotype is less prevalent in BD, vs. HC (pc = 2.4 × 10-2 ); (ii) the 57.1 and the 8.1-derived ancestral haplotypes i.e. HLA-A*02~B*57~Cw*06~DRB1*07~DQB1*09 and HLA-A*02~B*08~Cw*07 are associated with rapid cycling (pc = 1.9 × 10-3 and 1.05 × 10-2 , respectively); (iii) the 8.1AH-derived HLA class II-DRB*03~HLA-DQB1*02 sub-haplotype is more frequent in BD patients with a history of suicidal behaviors (pc = 2.1 × 10-2 ); and (iv) disease onset by an hypomanic episode or by psychotic symptoms are, respectively, more frequent in BD patients bearing the 7.1 AH-derived A*03~B*07~DRB1*15 sub-haplotype (pc = 8.5 × 10-3 ) and the HLA-A*02~B*07~DRB1*15 sub-haplotype (pc = 4.0 × 10-2 ). CONCLUSION Corroborating the established link between these HLA haplotypes/sub haplotypes and common immune disorders, our findings suggest possible HLA-mediated proinflammatory processes operating in BD.
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Martins J, Oliveira J, Taipa R, Garrido C, Melo Pires M, Santos M. CONGENITAL MYOPATHIES: NEMALINE AND TITINOPATHIES. Neuromuscul Disord 2018. [DOI: 10.1016/j.nmd.2018.06.273] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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Cordeiro E, Oliveira J, Santos M, Silva G, Oliveira T, Medeiros M, Di Mascio P, Loureiro A. Effects of Nicotinamide Riboside Supplementation on Benzo[a]pyrene Induced BEAS-2B Cell Transformation. Toxicol Lett 2018. [DOI: 10.1016/j.toxlet.2018.06.575] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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Reis P, Pereira R, Carvalho FP, Oliveira J, Malta M, Mendo S, Lourenço J. Life history traits and genotoxic effects on Daphnia magna exposed to waterborne uranium and to a uranium mine effluent - A transgenerational study. AQUATIC TOXICOLOGY (AMSTERDAM, NETHERLANDS) 2018; 202:16-25. [PMID: 29966909 DOI: 10.1016/j.aquatox.2018.06.009] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/04/2017] [Revised: 06/06/2018] [Accepted: 06/11/2018] [Indexed: 06/08/2023]
Abstract
Assessing the impact of uranium mining industry on aquatic ecosystems near mining areas is critical to ensure the long-term health and sustainability of ecosystem services. As so, a transgenerational study with Daphnia magna has been conducted to perceive to what extent intermittent discharges of uranium mine effluents into watercourses may impact the DNA integrity and life history traits of cladocerans. Organisms were exposed for 48 h to a 2% dilution of an uranium mine effluent (UME) and to a corresponding dose of waterborne uranium (WU) that, according to our preliminary studies, induces significant DNA damage in daphnids. After exposure, organisms were transferred to clean medium, where three successive generations were monitored for genotoxicity and other effects at the individual and population level. Despite some differences between WU and UME data, our results revealed that the negative impacts of the short-term exposure gradually disappeared after placing the organisms in clean medium. These results suggest that, under intermittent stress, daphnids are able to recover, since after the 3rd brood release, DNA damage (measured as DNA strand breaks) is no longer observed and has no significant impact on the detectable life traits of offspring. Although our results indicate that populations of D. magna are not affected by intermittent and highly diluted discharges from uranium mining, aquatic systems under this kind of pressure should not be seen as hazardous-free. Future studies in this field are recommended and these should consider radionuclides in the water column, their accumulation in the sediments and also multiple life stages.
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Moreira J, Paixão A, Oliveira J, Jaló W, Manuel O, Rodrigues R, Oliveira A, Tinoco L, Lima J, Grinsztejn B, Veloso VG, Japiassú AM, Lamas CC. Accuracy of quick sequential organ failure assessment score to predict mortality in hospitalized patients with suspected infection in an HIV/AIDS reference centre in Rio de Janeiro, Brazil. Clin Microbiol Infect 2018; 25:113.e1-113.e3. [PMID: 30118761 DOI: 10.1016/j.cmi.2018.08.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2018] [Revised: 07/31/2018] [Accepted: 08/04/2018] [Indexed: 10/28/2022]
Abstract
OBJECTIVES To compare the discriminatory capacity of the quick sequential organ failure assessment (qSOFA) vs. the systemic inflammatory response syndrome (SIRS) score for predicting 30-day mortality and intensive care unit (ICU) admission in patients with suspicion of infection at an HIV reference centre. METHODS We performed a prospective cohort study including consecutive adult patients who had suspected infection and who were subsequently admitted to the medical ward. Variables related to qSOFA and SIRS were measured at admission. The performance (area under the receiver operating curve, AUROC) of qSOFA (score ≥2) and SIRS (≥2 criteria) as a predictor of 30-day mortality and ICU admission was evaluated. RESULTS One hundred seventy-three patients (mean ± standard deviation age, 42.6 ± 12.4 years) were included in the analysis; 107 (61.8%) were male, and 111 (64.2%) were HIV positive. Respiratory and gastrointestinal infections occurred in 49 (28.3%) and 23 (13.3%), respectively. The 30-day mortality rate was 9 (5.2%) of 173. The prognostic performance of qSOFA was similar compared to SIRS, with an AUROC of 0.68 (95% confidence interval, 0.55-0.81) and 0.69 (95% confidence interval, 0.53-0.86) (p 0.96). Twenty patients (11%) were admitted to the ICU; qSOFA and SIRS had a similar discriminatory capacity for ICU admission (AUROC 0.63 (95% confidence interval, 0.51-0.75) and 0.63 (95% confidence interval, 0.50-0.76)), respectively). CONCLUSIONS We found a poor prognostic accuracy of the qSOFA to predict 30-day mortality in hospitalized patients suspected of infection in a setting with a high burden of HIV infection.
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Ferreira L, Palma I, Ramos H, Bacelar C, J queirós, Madureira A, Oliveira J, Cardoso H. Efficacy and tolerability of long-term lipoprotein apheresis in the management of severe hypercholesterolemia and of elevation of lipoprotein(a): Data from a single center in portugal. Atherosclerosis 2018. [DOI: 10.1016/j.atherosclerosis.2018.06.732] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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Paredes S, Fonseca L, Alves M, Vilaverde J, Oliveira J, Palma I. Lipid goals in patients with metabolic syndrome – Is low-density lipoprotein-cholesterol enough? Atherosclerosis 2018. [DOI: 10.1016/j.atherosclerosis.2018.06.064] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Braga A, Ferreira P, Oliveira J, Rocha I, Faria N. Heterologous production of resveratrol in bacterial hosts: current status and perspectives. World J Microbiol Biotechnol 2018; 34:122. [PMID: 30054757 DOI: 10.1007/s11274-018-2506-8] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2018] [Accepted: 07/19/2018] [Indexed: 12/16/2022]
Abstract
The polyphenol resveratrol (3,5,4'-trihydroxystilbene) is a well-known plant secondary metabolite, commonly used as a medical ingredient and a nutritional supplement. Due to its health-promoting properties, the demand for resveratrol is expected to continue growing. This stilbene can be found in different plants, including grapes, berries (blackberries, blueberries and raspberries), peanuts and their derived food products, such as wine and juice. The commercially available resveratrol is usually extracted from plants, however this procedure has several drawbacks such as low concentration of the product of interest, seasonal variation, risk of plant diseases and product stability. Alternative production processes are being developed to enable the biotechnological production of resveratrol by genetically engineering several microbial hosts, such as Escherichia coli, Corynebacterium glutamicum, Lactococcus lactis, among others. However, these bacterial species are not able to naturally synthetize resveratrol and therefore genetic modifications have been performed. The application of emerging metabolic engineering offers new possibilities for strain and process optimization. This mini-review will discuss the recent progress on resveratrol biosynthesis in engineered bacteria, with a special focus on the metabolic engineering modifications, as well as the optimization of the production process. These strategies offer new tools to overcome the limitations and challenges for microbial production of resveratrol in industry.
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Marques MM, Lobo V, Batista R, Oliveira J, Aguiar AP, Silva JE, de Sousa JB, Nunes MDF, Ribeiro RA, Bernardino A, Marques JS. An unmanned aircraft system for maritime operations. INT J ADV ROBOT SYST 2018. [DOI: 10.1177/1729881418786338] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
Unmanned air systems are becoming ever more important in modern societies but raise a number of unresolved problems. There are legal issues with the operation of these vehicles in nonsegregated airspace, and a pressing requirement to solve these issues is the development and testing of reliable and safe mechanisms to avoid collision in flight. In this article, we describe a sense and avoid subsystem developed for a maritime patrol unmanned air system. The article starts with a description of the unmanned air system, that was developed specifically for maritime patrol operations, and proceeds with a discussion of possible ways to guarantee that the unmanned air system does not collide with other flying objects. In the system developed, the position of the unmanned air system is obtained by the global positioning system and that of other flying objects is reported via a data link with a ground control station. This assumes that the detection of those flying objects is done by a radar in the ground or by self-reporting via a traffic monitoring system (such as automatic identification system). The algorithm developed is based on game theory. The approach is to handle both the procedures, threat detection phase and collision avoidance maneuver, in a unified fashion, where the optimal command for each possible relative attitude of the obstacle is computed off-line, therefore requiring low processing power for real-time operation. This work was done under the research project named SEAGULL that aims to improve maritime situational awareness using fleets of unmanned air system, where collision avoidance becomes a major concern.
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Reis P, Lourenço J, Carvalho FP, Oliveira J, Malta M, Mendo S, Pereira R. RIBE at an inter-organismic level: A study on genotoxic effects in Daphnia magna exposed to waterborne uranium and a uranium mine effluent. AQUATIC TOXICOLOGY (AMSTERDAM, NETHERLANDS) 2018; 198:206-214. [PMID: 29554637 DOI: 10.1016/j.aquatox.2018.03.007] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/10/2018] [Revised: 03/05/2018] [Accepted: 03/08/2018] [Indexed: 06/08/2023]
Abstract
The induction of RIBE (Radiation Induced Bystander Effect) is a non-target effect of low radiation doses that has already been verified at an inter-organismic level in fish and small mammals. Although the theoretical impact in the field of environmental risk assessment (ERA) is possible, there is a gap of knowledge regarding this phenomenon in invertebrate groups and following environmentally relevant exposures. To understand if RIBE should be considered for ERA of radionuclide-rich wastewaters, we exposed Daphnia magna (<24 h and 5d old) to a 2% diluted uranium mine effluent for 48 h, and to a matching dose of waterborne uranium (55.3 μg L-1). Then the exposed organisms were placed (24 and 48 h) in a clean medium together with non-exposed neonates. The DNA damage observed for the non-exposed organisms was statistically significant after the 24 h cohabitation for both uranium (neonates p = 0.002; 5 d-old daphnids p = <0.001) and uranium mine effluent exposure (only for neonates p = 0.042). After 48 h cohabitation significant results were obtained only for uranium exposure (neonates p = 0.017; 5 d-old daphnids p = 0.013). Although there may be some variability associated to age and exposure duration, the significant DNA damage detected in non-exposed organisms clearly reveals the occurrence of RIBE in D. magna. The data obtained and here presented are a valuable contribution for the discussion about the relevance of RIBE for environmental risk assessment.
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Oliveira J, Bragança AM, Alcácer L, Morgado J, Figueiredo M, Bioucas-Dias J, Ferreira Q. Sparse-coding denoising applied to reversible conformational switching of a porphyrin self-assembled monolayer induced by scanning tunnelling microscopy. J Microsc 2018; 271:98-108. [PMID: 29655172 DOI: 10.1111/jmi.12699] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2017] [Revised: 01/30/2018] [Accepted: 03/13/2018] [Indexed: 12/01/2022]
Abstract
Scanning tunnelling microscopy (STM) was used to induce conformational molecular switching on a self-assembled monolayer of zinc-octaethylporphyrin on a graphite/tetradecane interface at room temperature. A reversible conformational change controlled by applying a tip voltage was observed. Consecutive STM images acquired at alternating tip voltages showed that at 0.4 V the porphyrin monolayer presents a molecular arrangement formed by alternate rows with two different types of structural conformations and when the potential is increased to 0.7 V the monolayer presents only one type of conformation. In this paper, we characterize these porphyrin conformational dynamics by analyzing the STM images, which were improved for better quality and interpretation by means of a denoising algorithm, adapted to process STM images from state of the art image processing and analysis methods. STM remains the best technique to 'see' and to manipulate the matter at atomic scale. A very sharp tip a few angstroms of the surface can provide images of molecules and atoms with a powerful resolution. However, these images are strongly affected by noise which is necessary to correct and eliminate. This paper is about new computational tools specifically developed to denoise the images acquired with STM. The new algorithms were tested in STM images, obtained at room temperature, of porphyrin monolayer which presents reversible conformational change in function of the tip bias voltage. Images with high resolution, acquired in real time, show that the porphyrins have different molecular arrangements whether the tip voltage is 0.4 V or 0.7 V.
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