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1.
Sci Rep ; 13(1): 13561, 2023 08 21.
Article in English | MEDLINE | ID: mdl-37604835

ABSTRACT

Cyanobacterial exopolysaccharides (EPS) are potential candidates for the production of sustainable biopolymers. Although the bioactive and physicochemical properties of cyanobacterial-based EPS are attractive, their commercial exploitation is limited by the high production costs. Bioprospecting and characterizing novel EPS-producing strains for industrially relevant conditions is key to facilitate their implementation in various biotechnological applications and fields. In the present work, we selected twenty-five Portuguese cyanobacterial strains from a diverse taxonomic range (including some genera studied for the first time) to be grown in diel light and temperature, simulating the Portuguese climate conditions, and evaluated their growth performance and proximal composition of macronutrients. Synechocystis and Cyanobium genera, from marine and freshwater origin, were highlighted as fast-growing (0.1-0.2 g L-1 day-1) with distinct biomass composition. Synechocystis sp. LEGE 07367 and Chroococcales cyanobacterium LEGE 19970, showed a production of 0.3 and 0.4 g L-1 of released polysaccharides (RPS). These were found to be glucan-based polymers with high molecular weight and a low number of monosaccharides than usually reported for cyanobacterial EPS. In addition, the absence of known cyanotoxins in these two RPS producers was also confirmed. This work provides the initial steps for the development of cyanobacterial EPS bioprocesses under the Portuguese climate.


Subject(s)
Bioprospecting , Synechocystis , Portugal , Climate , Temperature
2.
Infect Dis Rep ; 15(2): 171-179, 2023 Mar 16.
Article in English | MEDLINE | ID: mdl-36960970

ABSTRACT

We report a fatal case of disseminated mpox infection that progressed over more than three months in an HIV-infected patient with acquired immunodeficiency syndrome (AIDS). Mucocutaneous, pleuropulmonary, central nervous system, and gastrointestinal involvement was documented. This course of disease resembles progressive vaccinia, a formerly reported disease caused by uncontrolled replication of smallpox vaccination orthopoxviruses in immunosuppressed patients. Severe small bowel involvement jeopardized normal oral tecovirimat and antiretroviral therapy absorption. This problem prompted the use of full parenteral antiretrovirals and endovenous cidofovir. Although a remarkable decrease in HIV viral load occurred in six days, mpox infection continued to progress, and the patient died of septic shock. This case offers new clinical insights on the presentation of severe disease in AIDS patients. Moreover, this case alerts for the need for prompt therapy initiation in patients at risk of ominous clinical progression.

3.
Foods ; 12(3)2023 Jan 23.
Article in English | MEDLINE | ID: mdl-36766042

ABSTRACT

Coccolithophore microalgae, such as Emiliania huxleyi (EHUX) and Chrysotila pseudoroscoffensis (CP), are composed of calcium carbonate (CaCO3) and contain bioactive compounds that can be explored to produce sustainable food packaging. In this study, for the first time, these microalgae were incorporated as fillers in starch-based films, envisioning the development of biodegradable and bioactive materials for food packaging applications. The films were obtained by solvent casting using different proportions of the filler (2.5, 5, 10, and 20%, w/w). For comparison, commercial CaCO3, used as filler in the plastic industry, was also tested. The incorporation of CaCO3 and microalgae (EHUX or CP) made the films significantly less rigid, decreasing Young's modulus up to 4.7-fold. Moreover, the incorporation of microalgae hydrophobic compounds as lipids turned the surface hydrophobic (water contact angles > 90°). Contrary to what was observed with commercial CaCO3, the films prepared with microalgae exhibited antioxidant activity, increasing from 0.9% (control) up to 60.4% (EHUX 20%) of ABTS radical inhibition. Overall, the introduction of microalgae biomass improved hydrophobicity and antioxidant capacity of starch-based films. These findings should be considered for further research using coccolithophores to produce active and sustainable food packaging material.

4.
Cureus ; 15(1): e33670, 2023 Jan.
Article in English | MEDLINE | ID: mdl-36793831

ABSTRACT

Hand-foot-mouth syndrome is a common childhood illness. Although occurrence in adults is rare, its incidence has been increasing. In such cases, it usually presents with atypical symptoms. The authors present the case of a 33-year-old male patient who presented with constitutional symptoms, feverish sensation, and macular palmoplantar rash associated with oral and oropharynx ulcers. The epidemiological history revealed exposure to two cohabitants (children) with a recent diagnosis of hand-foot-mouth disease (HFMD).

5.
Foods ; 11(13)2022 Jun 24.
Article in English | MEDLINE | ID: mdl-35804687

ABSTRACT

Microalgae are considered a promising resource of proteins, lipids, carbohydrates, and other functional biomolecules for food and feed markets. Competitive drying solutions are required to meet future demands for high-quality algal biomass while ensuring proper preservation at reduced costs. Since often used drying methods, such as freeze or spray drying, are energy and time consuming, more sustainable processes remain to be developed. This study tested an indirect and hybrid solar dryer as an alternative to conventional freeze drying of industrially produced Tetraselmis chui and Nannochloropsis oceanica wet paste. The effects of the drying method on biomass quality parameters, including biochemical profiles, functional properties, and microbial safety, were assessed. No significant differences were found between the applied drying technologies for total proteins, carbohydrates, lipids, and fatty acid profiles. On the other hand, some pigments showed significant differences, displaying up to 44.5% higher contents in freeze-dried samples. Minor differences were also registered in the mineral profiles (<10%). Analyses of microbial safety and functional properties of the solar-dried biomass appear adequate for food and feed products. In conclusion, industrial solar drying is a sustainable technology with a high potential to preserve high-quality microalgal biomass for various markets at expected lower costs.

6.
Biology (Basel) ; 11(4)2022 Apr 14.
Article in English | MEDLINE | ID: mdl-35453793

ABSTRACT

S. costatum and C. calcitrans are two cosmopolitan high-value centric diatoms, with a rich nutritional profile. The following work optimised the culture medium of S. costatum and C. calcitrans cultures, respectively, in a stepwise process as follows: 2.4 mM and 1.2 mM of silicate, 4 mM of nitrate, 100 µM of phosphate, 20 and 80 µM iron, and 0.5 mL L-1 of micronutrients. The results that were obtained revealed an increase in biomass productivity with a 1.8- and 3.2-fold increase in biomass that was produced by S. costatum and C. calcitrans, respectively. The biochemical profile showed an increase in high-value PUFAs such as 2.6-fold and 2.3-fold increase in EPA for S. costatum and C. calcitrans, respectively, whilst a 2.6-fold increase in DHA was detected in S. costatum cultures. The present work provides the basic tools for the industrial cultivation of S. costatum and C. calcitrans with enhanced productivity as well as improved biomass quality, two factors which are highly relevant for a more effective application of these diatoms to aquaculture and nutraceutical production.

7.
J Biotechnol ; 343: 110-119, 2022 Jan 10.
Article in English | MEDLINE | ID: mdl-34856224

ABSTRACT

Diatoms are currently considered valuable feedstocks for different biotechnological applications. To deepen the knowledge on the production of these microalgae, the diel pattern of batch growth, photosystem II performance, and accumulation of target metabolites of two commercially relevant diatoms, Phaeodactylum tricornutum and Skeletonema costatum, were followed outdoors in 100-L flat panel photobioreactors. S. costatum presented a higher light-to-biomass conversion resulting in higher growth than P. tricornutum. Both fluorescence data and principal component analysis pointed to temperature as a limiting factor for the growth of P. tricornutum. Higher protein and carbohydrate contents were found in P. tricornutum, whereas S. costatum fatty acids were characterized by a higher unsaturation degree. Higher productivities were found at 1 p.m. for protein, lipid, and ash in the case of S. costatum. Overall, S. costatum showed great potential for outdoor cultivation, revealing a broader temperature tolerance and increased biomass productivity than P. tricornutum.


Subject(s)
Diatoms , Microalgae , Biomass , Photobioreactors , Photosynthesis
8.
Cureus ; 13(11): e19307, 2021 Nov.
Article in English | MEDLINE | ID: mdl-34900483

ABSTRACT

Hypereosinophilic syndrome is a rare condition characterized by eosinophilia associated with organ damage, most commonly affecting the skin, lung, gastrointestinal, cardiovascular and central nervous system. The idiopathic form is characterized by the absence of other conditions associated with hypereosinophilia such as allergies, infectious, hematological, immunological, endocrine or neoplasm diseases. The authors present a clinical case of a 70-year-old man with no relevant history, who went to the emergency department for neurological deficits and nonspecific chest pain. Laboratory tests revealed marked eosinophilia, elevation of cardiac enzymes with normal electrocardiogram. Computed tomography of the head showed multiple bilateral ischemic lesions. Upon further investigation for the cerebrovascular disease, transesophageal echocardiogram showed a thrombus at the aortic arch, as a probable embolic source. Despite anticoagulant therapy and corticosteroids, the patient's status deteriorated, with multiple successive ischemic strokes and worsening neurological deficits. After a thorough investigation, the diagnosis of idiopathic eosinophilia was established.

9.
Biotechnol Bioeng ; 118(11): 4375-4388, 2021 11.
Article in English | MEDLINE | ID: mdl-34319592

ABSTRACT

In situ chlorophyll a fluorescence measurements were applied to monitor changes in the photochemical variables of Nannochloropsis oceanica cultures under nitrogen-deplete and nitrogen-replete (control) conditions. In addition, growth, lipid, fatty acid, and pigment contents were also followed. In the control culture, growth was promoted along with pigment content, electron transport rate (ETR), and polyunsaturated fatty acids, while total lipid content and fatty acid saturation level diminished. Under nitrogen-deplete conditions, the culture showed a higher de-epoxidation state of the xanthophyll cycle pigments. Fast transients revealed a poor processing efficiency for electron transfer beyond QA , which was in line with the low ETR due to nitrogen depletion. Lipid content and the de-epoxidation state were the first biochemical variables triggered by the change in nutrient status, which coincided with a 20% drop in the in situ effective quantum yield of PSII (ΔF'/Fm '), and a raise in the Vj measurements. A good correlation was found between the changes in ΔF'/Fm ' and lipid content (r = -0.96, p < 0.01). The results confirm the reliability and applicability of in situ fluorescence measurements to monitor lipid induction in N. oceanica.


Subject(s)
Chlorophyll A/metabolism , Fatty Acids/biosynthesis , Fluorescence , Photosynthesis , Stramenopiles/growth & development
10.
Bioresour Technol ; 337: 125385, 2021 Oct.
Article in English | MEDLINE | ID: mdl-34147770

ABSTRACT

In this study, two carotenoid-rich strains of the euryhaline microalga Tetraselmis striata CTP4 were isolated by random mutagenesis combined with selection via fluorescence activated cell sorting and growth on norflurazon. Both strains, ED5 and B11, showed an up to 1.5-fold increase in carotenoid contents as compared with the wildtype, independent of the growth conditions. More specifically, violaxanthin, ß-carotene and lutein contents reached as high as 1.63, 4.20 and 3.81 mg g-1 DW, respectively. Genes coding for phytoene synthase, phytoene desaturase, lycopene-ß-cyclase and ε-ring hydroxylase involved in carotenoid biosynthesis were found to be upregulated in ED5 and B11 cells as compared to the wildtype. Both strains showed higher contents of eicosapentaenoic acid as compared with those of the wildtype, reaching up to 4.41 and 2.88 mg g-1 DW, respectively. Overall, these results highlight the complexity of changes in carotenoid biosynthesis regulation that are required to improve pigment contents in microalgae.


Subject(s)
Fatty Acids, Omega-3 , Carotenoids , Gene Expression , Gene Expression Regulation, Plant , Heat-Shock Response , beta Carotene
11.
Eur J Case Rep Intern Med ; 8(3): 002304, 2021.
Article in English | MEDLINE | ID: mdl-33768077

ABSTRACT

Granulomatosis with polyangiitis (Wegener's granulomatosis) is a systemic vasculitis that primarily affects small and medium vessels. Its manifestations are usually confined to the upper airway, lower airway and kidney. It can also affect other organs and systems, although this is unusual. We describe the case of a 67-year-old woman who presented with a tension pneumothorax due to rupture of a pulmonary cavity. This pulmonary cavity proved to be secondary to systemic disease which also caused a tumour in her kidney. Biopsy showed non-necrotizing granulomatosis, and even though antineutrophil cytoplasmic antibodies (ANCA) were negative, the diagnosis of granulomatosis with polyangiitis was made. LEARNING POINTS: Granulomatosis with polyangiitis (GPA) can be a challenging diagnosis when the initial manifestation is atypical, so a careful history and physical examination are needed to make the diagnosis.It is not uncommon for patients with multisystemic inflammatory disease to attend several different specialty clinics before the diagnosis is reached.GPA with negative ANCA is rare, and occurs more frequently in non-severe forms of the disease.

12.
Omega (Westport) ; 83(4): 927-943, 2021 Sep.
Article in English | MEDLINE | ID: mdl-31466508

ABSTRACT

This article analyzes suicidal behavior and how its inherent processes of death ideation can overlap with those seeking euthanasia. We present a literature review of three main events in suicide (suicidal ideation, suicide attempt, and suicide) in different populations and evaluate implications for health-care practice and risk assessment taking into account the context of euthanasia. We ponder upon the motives behind suicide and its link with wish to die requests to hasten death. We discuss the possibility of the reversal of a wish to die as well as a potential process of differentiating between individuals who would maintain their wish and benefit from termination of life and others who would later change their minds.


Subject(s)
Attitude to Death , Euthanasia , Humans , Suicidal Ideation , Suicide, Attempted , Suicide, Completed
13.
Rev. bras. ter. intensiva ; 32(4): 571-577, out.-dez. 2020. tab, graf
Article in English, Spanish | LILACS | ID: biblio-1156252

ABSTRACT

RESUMEN Objetivo: Describir los resultados de la implementación de un protocolo de cuidados respiratorios y de ventilación mecánica en el potencial donante de pulmón, que cumplen las condiciones para ser procurados. El objetivo secundario es comparar los resultados con datos históricos. Métodos: Estudio retrospectivo y observacional. Incluye potenciales donantes aptos para procuración de órganos con muerte encefálica internados en las áreas críticas de la Ciudad Autónoma de Buenos Aires, desde abril de 2017 hasta marzo de 2018. Variables principales: número de potencial donante de pulmón que alcanzan el objetivo de procuración, tasa de pulmones procurados y tasa de pulmones implantados. Se consideraron valores significativos p < 0,05. Resultados: Se incluyeron 30 potenciales donantes de pulmón, 23 (88.5%; IC95% 69,8 - 97,6) cumplieron el objetivo de oxigenación. Veinte potenciales donantes de pulmón donaron órganos y de ellos, ocho donaron pulmones, con los cuales se realizaron 4 trasplantes bipulmonares y 8 unipulmonares. Los pulmones procurados e implantados en el periodo pre-protocolo fueron 7, mientras que durante el protocolo fueron 12 (valor p = 0,38). La tasa de implantación fue 58,3% (7/12) en el control histórico y 100% (12/12) (valor p = 0,04) en el periodo de estudio. Conclusión: El protocolo permitió alcanzar el objetivo de oxigenación en la mayoría de los potenciales donantes de pulmón y una mejoría estadísticamente significativa en la tasa de implantación.


ABSTRACT Objective: To describe the results from the implementation of a respiratory care and mechanical ventilation protocol on potential lung donors who met the conditions for procurement. The secondary objective is to compare the results with historical data. Methods: This was a retrospective, observational study. It included potential donors suitable for procurement of organs who had brain death and were hospitalized in critical care units of the Autonomous City of Buenos Aires from April 2017 to March 2018. Main variables: number of potential lung donors that reached the objective of procurement, rate of lungs procured, and rate of implanted lungs. Values of p < 0.05 were considered significant. Results: Thirty potential lung donors were included, and 23 (88.5%; 95%CI 69.8 - 97.6) met the oxygenation objective. Twenty potential lung donors donated organs, of whom eight donated lungs, with which four double lung transplants and eight single lung transplants were performed. Seven of 12 lungs were procured and implanted in the preprotocol period, while all 12 were under the protocol (p = 0.38). The implantation rate was 58.3% (7/12) in the historical control period and 100% (12/12) (p = 0.04) in the study period.


Subject(s)
Humans , Tissue and Organ Procurement , Lung Transplantation , Respiration, Artificial , Tissue Donors , Brain Death , Retrospective Studies , Lung
14.
Biomolecules ; 10(10)2020 10 12.
Article in English | MEDLINE | ID: mdl-33053668

ABSTRACT

Polar lipids from microalgae have aroused greater interest as a natural source of omega-3 (n-3) polyunsaturated fatty acids (PUFA), an alternative to fish, but also as bioactive compounds with multiple applications. The present study aims to characterize the polar lipid profile of cultured microalga Emiliania huxleyi using hydrophilic interaction liquid chromatography coupled with high-resolution mass spectrometry (HILIC-MS) and fatty acids (FA) analysis by gas chromatography (GC-MS). The lipidome of E. huxleyi revealed the presence of distinct n-3 PUFA (40% of total FA), namely docosahexaenoic acid (22:6n-3) and stearidonic acid (18:4n-3), which give this microalga an increased commercial value as a source of n-3 PUFA present in the form of polar lipids. A total of 134 species of polar lipids were identified and some of these species, particularly glycolipids, have already been reported for their bioactive properties. Among betaine lipids, the diacylglyceryl carboxyhydroxymethylcholine (DGCC) class is the least reported in microalgae. For the first time, monomethylphosphatidylethanolamine (MMPE) has been found in the lipidome of E. huxleyi. Overall, this study highlights the potential of E. huxleyi as a sustainable source of high-value polar lipids that can be exploited for different applications, namely human and animal nutrition, cosmetics, and pharmaceuticals.


Subject(s)
Haptophyta/chemistry , Lipids/analysis , Biotechnology/methods , Cells, Cultured , Chromatography, Liquid , Gas Chromatography-Mass Spectrometry , Haptophyta/growth & development , Haptophyta/metabolism , Lipid Metabolism , Lipidomics , Metabolic Engineering/methods , Microbiological Techniques , Tandem Mass Spectrometry
15.
Article in English | MEDLINE | ID: mdl-32509750

ABSTRACT

Microalgae are widely used as food supplements due to their high protein content, essential fatty acids and amino acids as well as carotenoids. The addition of microalgal biomass to food products (e.g., baked confectioneries) is a common strategy to attract novel consumers. However, organoleptic factors such as color, taste and smell can be decisive for the acceptability of foods supplemented with microalgae. The aim of this work was to develop chlorophyll-deficient mutants of Chlorella vulgaris by chemically induced random mutagenesis to obtain biomass with different pigmentations for nutritional applications. Using this strategy, two C. vulgaris mutants with yellow (MT01) and white (MT02) color were successfully isolated, scaled up and characterized. The changes in color of MT01 and MT02 mutant strains were due to an 80 and 99% decrease in their chlorophyll contents, respectively, as compared to the original wild type (WT) strain. Under heterotrophic growth, MT01 showed a growth performance similar to that of the WT, reaching a concentration of 5.84 and 6.06 g L-1, respectively, whereas MT02 displayed slightly lower growth (4.59 g L-1). When grown under a light intensity of 100 µmol m-2 s-1, the pigment content in MT01 increased without compromising growth, while MT02 was not able to grow under this light intensity, a strong indication that it became light-sensitive. The yellow color of MT01 in the dark was mainly due to the presence of the xanthophyll lutein. On the other hand, phytoene was the only carotenoid detected in MT02, which is known to be colorless. Concomitantly, MT02 contained the highest protein content, reaching 48.7% of DW, a 60% increase as compared to the WT. MT01 exhibited a 30% increase when compared to that of the WT, reaching a protein content of 39.5% of DW. Taken together, the results strongly suggest that the partial abrogation of pigment biosynthesis is a factor that might promote higher protein contents in this species. Moreover, because of their higher protein and lower chlorophyll contents, the MT01 and MT02 strains are likely candidates to be feedstocks for the development of novel, innovative food supplements and foods.

16.
Micromachines (Basel) ; 11(4)2020 Mar 26.
Article in English | MEDLINE | ID: mdl-32224993

ABSTRACT

Air inside of blood vessels is a phenomenon known as gas embolism. During the past years, studies have been performed to assess the influence of air bubbles in microcirculation. In this study, we investigated the flow of bubbles in a microchannel network with several bifurcations, mimicking part of a capillary system. Thus, two working fluids were used, composed by sheep red blood cells (RBCs) suspended in a Dextran 40 solution with different hematocrits (5% and 10%). The experiments were carried out in a polydimethylsiloxane (PDMS) microchannel network fabricated by a soft lithography. A high-speed video microscopy system was used to obtain the results for a blood flow rate of 10 µL/min. This system enables the visualization of bubble formation and flow along the network. The results showed that the passage of air bubbles strongly influences the cell's local concentration, since a higher concentration of cells was observed upstream of the bubble, whereas a lower local hematocrit was visualized at the region downstream of the bubble. In bifurcations, bubbles may split asymmetrically, leading to an uneven distribution of RBCs between the outflow branches.

17.
Rev Bras Ter Intensiva ; 32(4): 571-577, 2020.
Article in Spanish, English | MEDLINE | ID: mdl-33470359

ABSTRACT

OBJECTIVE: To describe the results from the implementation of a respiratory care and mechanical ventilation protocol on potential lung donors who met the conditions for procurement. The secondary objective is to compare the results with historical data. METHODS: This was a retrospective, observational study. It included potential donors suitable for procurement of organs who had brain death and were hospitalized in critical care units of the Autonomous City of Buenos Aires from April 2017 to March 2018. Main variables: number of potential lung donors that reached the objective of procurement, rate of lungs procured, and rate of implanted lungs. Values of p < 0.05 were considered significant. RESULTS: Thirty potential lung donors were included, and 23 (88.5%; 95%CI 69.8 - 97.6) met the oxygenation objective. Twenty potential lung donors donated organs, of whom eight donated lungs, with which four double lung transplants and eight single lung transplants were performed. Seven of 12 lungs were procured and implanted in the preprotocol period, while all 12 were under the protocol (p = 0.38). The implantation rate was 58.3% (7/12) in the historical control period and 100% (12/12) (p = 0.04) in the study period.


OBJETIVO: Describir los resultados de la implementación de un protocolo de cuidados respiratorios y de ventilación mecánica en el potencial donante de pulmón, que cumplen las condiciones para ser procurados. El objetivo secundario es comparar los resultados con datos históricos. MÉTODOS: Estudio retrospectivo y observacional. Incluye potenciales donantes aptos para procuración de órganos con muerte encefálica internados en las áreas críticas de la Ciudad Autónoma de Buenos Aires, desde abril de 2017 hasta marzo de 2018. Variables principales: número de potencial donante de pulmón que alcanzan el objetivo de procuración, tasa de pulmones procurados y tasa de pulmones implantados. Se consideraron valores significativos p < 0,05. RESULTADOS: Se incluyeron 30 potenciales donantes de pulmón, 23 (88.5%; IC95% 69,8 - 97,6) cumplieron el objetivo de oxigenación. Veinte potenciales donantes de pulmón donaron órganos y de ellos, ocho donaron pulmones, con los cuales se realizaron 4 trasplantes bipulmonares y 8 unipulmonares. Los pulmones procurados e implantados en el periodo pre-protocolo fueron 7, mientras que durante el protocolo fueron 12 (valor p = 0,38). La tasa de implantación fue 58,3% (7/12) en el control histórico y 100% (12/12) (valor p = 0,04) en el periodo de estudio. CONCLUSIÓN: El protocolo permitió alcanzar el objetivo de oxigenación en la mayoría de los potenciales donantes de pulmón y una mejoría estadísticamente significativa en la tasa de implantación.


Subject(s)
Lung Transplantation , Tissue and Organ Procurement , Brain Death , Humans , Lung , Respiration, Artificial , Retrospective Studies , Tissue Donors
19.
Front Psychol ; 8: 1911, 2017.
Article in English | MEDLINE | ID: mdl-29204128

ABSTRACT

Ecological validity should be the cornerstone of any assessment of cognitive functioning. For this purpose, we have developed a preliminary study to test the Art Gallery Test (AGT) as an alternative to traditional neuropsychological testing. The AGT involves three visual search subtests displayed in a virtual reality (VR) art gallery, designed to assess visual attention within an ecologically valid setting. To evaluate the relation between AGT and standard neuropsychological assessment scales, data were collected on a normative sample of healthy adults (n = 30). The measures consisted of concurrent paper-and-pencil neuropsychological measures [Montreal Cognitive Assessment (MoCA), Frontal Assessment Battery (FAB), and Color Trails Test (CTT)] along with the outcomes from the three subtests of the AGT. The results showed significant correlations between the AGT subtests describing different visual search exercises strategies with global and specific cognitive measures. Comparative visual search was associated with attention and cognitive flexibility (CTT); whereas visual searches involving pictograms correlated with global cognitive function (MoCA).

20.
Methods Inf Med ; 56(2): 112-116, 2017 Mar 23.
Article in English | MEDLINE | ID: mdl-27922659

ABSTRACT

BACKGROUND: An adequate behavioral response depends on attentional and mnesic processes. When these basic cognitive functions are impaired, the use of non-immersive Virtual Reality Applications (VRAs) can be a reliable technique for assessing the level of impairment. However, most non-immersive VRAs use indirect measures to make inferences about visual attention and mnesic processes (e.g., time to task completion, error rate). OBJECTIVES: To examine whether the eye movement analysis through eye tracking (ET) can be a reliable method to probe more effectively where and how attention is deployed and how it is linked with visual working memory during comparative visual search tasks (CVSTs) in non-immersive VRAs. METHODS: The eye movements of 50 healthy participants were continuously recorded while CVSTs, selected from a set of cognitive tasks in the Systemic Lisbon Battery (SLB). Then a VRA designed to assess of cognitive impairments were randomly presented. RESULTS: The total fixation duration, the number of visits in the areas of interest and in the interstimulus space, along with the total execution time was significantly different as a function of the Mini Mental State Examination (MMSE) scores. CONCLUSIONS: The present study demonstrates that CVSTs in SLB, when combined with ET, can be a reliable and unobtrusive method for assessing cognitive abilities in healthy individuals, opening it to potential use in clinical samples.


Subject(s)
Cognition/physiology , Eye Movements/physiology , Task Performance and Analysis , User-Computer Interface , Adolescent , Adult , Female , Humans , Male , Middle Aged , Time Factors , Young Adult
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