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Lopes BRP, Albertini TT, Costa MF, Ferreira AS, Toledo KA, Rocha JC. The use of Artificial Intelligence in predicting Respiratory Syncytial Virus-inhibiting flavonoids. BRAZ J BIOL 2023; 83:e270776. [PMID: 37255172 DOI: 10.1590/1519-6984.270776] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2022] [Accepted: 04/08/2023] [Indexed: 06/01/2023] Open
Abstract
Human Respiratory Syncytial Virus (hRSV) infection results in death and hospitalization of thousands of people worldwide each year. Unfortunately, there are no vaccines or specific treatments for hRSV infections. Screening hundreds or even thousands of promising molecules is a challenge for science. We integrated biological, structural, and physicochemical properties to train and to apply the concept of artificial intelligence (AI) able to predict flavonoids with potential anti-hRSV activity. During the training and simulation steps, the AI produced results with hit rates of more than 83%. The better AIs were able to predict active or inactive flavonoids against hRSV. In the future, in vitro and/or in vivo evaluations of these flavonoids may accelerate trials for new anti-RSV drugs, reduce hospitalizations, deaths, and morbidity caused by this infection worldwide, and be used as input in these networks to determine which parameter is more important for their decision.
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Affiliation(s)
- B R P Lopes
- Universidade Estadual Paulista - UNESP, Faculdade de Ciências e Letras, Departamento de Ciências Biológicas, Assis, SP, Brasil
| | - T T Albertini
- Universidade Estadual Paulista - UNESP, Faculdade de Ciências e Letras, Departamento de Ciências Biológicas, Assis, SP, Brasil
- Universidade Estadual Paulista - UNESP, Faculdade de Ciências e Letras, Laboratório de Matemática Aplicada, Assis, SP, Brasil
| | - M F Costa
- Universidade Estadual Paulista - UNESP, Faculdade de Ciências e Letras, Departamento de Ciências Biológicas, Assis, SP, Brasil
- Universidade Estadual Paulista - UNESP, Instituto de Biociências Letras e Ciências Exatas, Pós-graduação em Microbiologia, São José do Rio Preto, SP, Brasil
| | - A S Ferreira
- Universidade Estadual Paulista - UNESP, Faculdade de Ciências e Letras, Departamento de Ciências Biológicas, Assis, SP, Brasil
- Universidade Estadual Paulista - UNESP, Faculdade de Ciências e Letras, Laboratório de Matemática Aplicada, Assis, SP, Brasil
| | - K A Toledo
- Universidade Estadual Paulista - UNESP, Faculdade de Ciências e Letras, Departamento de Ciências Biológicas, Assis, SP, Brasil
- Universidade Estadual Paulista - UNESP, Instituto de Biociências Letras e Ciências Exatas, Pós-graduação em Microbiologia, São José do Rio Preto, SP, Brasil
| | - J C Rocha
- Universidade Estadual Paulista - UNESP, Faculdade de Ciências e Letras, Departamento de Ciências Biológicas, Assis, SP, Brasil
- Universidade Estadual Paulista - UNESP, Faculdade de Ciências e Letras, Laboratório de Matemática Aplicada, Assis, SP, Brasil
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Mane FG, Flores R, Silva R, Conde I, Rodrigues C, Medeiros P, Oliveira C, Campos I, Ferreira AS, Costa J, Quina C, Braga C, Marques J. On- vs off-hours primary percutaneous coronary intervention: a single-centre experience. Eur Heart J 2021. [DOI: 10.1093/eurheartj/ehab724.1438] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Abstract
Introduction
In ST-segment elevation myocardial infarction (STEMI) patients, emergency medical system delays importantly affect outcomes. The effect of admission time in STEMI patients is dubious when percutaneous coronary intervention (PCI) is the preferred reperfusion strategy.
Aims
The authors aimed to retrospectively describe the association between admission time and STEMI patient's care standards and outcomes.
Methods
Characteristics and outcomes of 1222 consecutive STEMI patients treated in a PCI-centre were collected. On-hours were defined as admission on non-national-holidays from Monday to Friday from 8 AM to 6 PM. Time delays, in-hospital and one-year all-cause mortality were assessed.
Results
A total of 439 patients (36%) were admitted on-hours and 783 patients (64%) were admitted off-hours. Baseline characteristics were well-balanced between groups, including the percentage of patients admitted in cardiogenic shock (on-hours: 4.6% vs off-hours 4%; p=0.62).
Median emergency system dependent time to reperfusion (i.e. first-medical contact to reperfusion) did not differ between the two groups (on-hours: 120 min vs. off-hours 123 min, p=0.54). The authors observed no association between admission time and in-hospital mortality (on-hours: 5% vs. off-hours 4.9%, p=0.90) or 1-year mortality (on-hours: 10% vs. off-hours 10%, p=0.97).
In patients admitted directly in the PCI-centre, median time from first-medical contact to reperfusion (on-hours: 87 min vs off-hours: 88 min, p=0.54), in-hospital mortality (on-hours: 4% vs off-hours: 7%, p=0.30) and 1 year mortality (on-hours: 9% vs off-hours: 13%, p=0.27) did not differ between the two groups.
Survival analysis showed no survival benefit of on-hours PCI over off-hours PCI (HR 1.01; 95% CI [0.77–1.46], p=0.95).
Conclusion
In a contemporary well-organized emergency network, STEMI patients admission time in the PCI-centre was not associated with reperfusion delays or increased mortality.
Funding Acknowledgement
Type of funding sources: None. Kaplan-Meier curve
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Affiliation(s)
- F G Mane
- Hospital de Braga, Braga, Portugal
| | - R Flores
- Hospital de Braga, Braga, Portugal
| | - R Silva
- Hospital de Braga, Braga, Portugal
| | - I Conde
- Hospital de Braga, Braga, Portugal
| | | | | | | | - I Campos
- Hospital de Braga, Braga, Portugal
| | - A S Ferreira
- ULSAM - Hospital de Santa Luzia, Internal Medicine, Viana do Castelo, Portugal
| | - J Costa
- Hospital de Braga, Braga, Portugal
| | - C Quina
- Hospital de Braga, Braga, Portugal
| | - C Braga
- Hospital de Braga, Braga, Portugal
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Silva AGS, Rocha AFS, Paula FD, Nunes PM, Garcia LN, Pacheco LSC, Nunes RKD, Ferreira AS, Abreu MTCL. INTENÇÃO DO ATIRADOR DO TIRO DE GUERRA PARA A DOAÇÃO DE SANGUE E AO CADASTRO PARA DOAÇÃO DE MEDULA ÓSSEA. Hematol Transfus Cell Ther 2021. [DOI: 10.1016/j.htct.2021.10.590] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022] Open
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Alegre L, Bori L, Coello A, Ferreira AS, Rocha JC, Cobo A, Meseguer M. P–135 Artificial neural networks (ANNs) for live birth prediction in frozen embryo transfers: the strength of post-warmed blastocyst dynamics. Hum Reprod 2021. [DOI: 10.1093/humrep/deab130.134] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Abstract
Study question
Does the post-warmed blastocyst dynamics have an impact over the likelihood of achieving a live birth?
Summary answer
Variables related to dynamics of vitrified/warmed blastocysts have shown a greater effect on the live birth prediction than only embryo morphological quality through artificial intelligence.
What is known already
Morphological dynamics of vitrified/warmed blastocysts were described by Coello et al., in 2017. The investigated markers were the thickness of zona pellucida (µm) and blastocysts area (µm2) after warming and before transfer, the area of the inner cell mass (µm2), time of initiation of reexpansion (in minutes), and presence of collapse or contraction. They found a correlation between blastocyst reexpansion and implantation rate and developed a hierarchical model for implantation prediction. In our study, we evaluated the post-warmed blastocyst dynamics for live birth prediction by using novel artificial intelligence techniques.
Study design, size, duration
This retrospective analysis included 415 vitrified/warmed blastocysts with known live birth data. Blastocysts after warming were placed in EmbryoScope (Vitrolife) immediately until embryo transfer. Embryo evaluation and selection were performed by senior embryologists according to fresh blastocyst morphology (before vitrification). Then, parameters related to post-warmed blastocyst dynamics were calculated. Finally, these variables and the embryo morphological grade before the vitrification were used as input data for ANNs optimized with genetic algorithm for live birth prediction.
Participants/materials, setting, methods
Blastocysts were vitrified and warmed by the Cryotop method (Kitazato,Biopharma). During the period between the warming procedure and the embryo transfer, the following variables were measured with the drawing tools provided by the EmbryoViewer workstation: zona pellucida thinning (µm), blastocyst expansion (um) and the speed of these two events (µm/h). Finally, multilayer perceptron neural networks were trained with data of 331 embryos by using the backpropagation learning algorithm and tested with data of 84 embryos.
Main results and the role of chance
We trained and tested three architectures of ANNs with different input variables as follows: post-warmed variables (thinning of the zona pellucida, blastocyst expansion, thinning speed and expansion speed) and morphological grade (A, B or C) for ANN1, only post-warmed variables for ANN2 and only morphological grade for ANN3. The highest success rate when ANNs classified embryos as positive and negative live birth (LB+ and LB-) was achieved by combining post-warmed variables and morphological grade before embryo vitrification. The general accuracies for the blind tests were: 73.8% for ANN1, 66.7% for ANN2 and 71.4% for ANN3. Likewise, this combination achieved the highest AUC on test dataset to predict LB- (0.76 for ANN1, 0.74 for ANN2 and 0.67 for ANN3). However, the ANN2 trained with only post-warmed variables showed the best capacity to predict LB+ with an AUC of 0.73 (versus 0.46 for ANN1 and 0.5 for ANN3).
Limitations, reasons for caution
The main limitation is the subjectivity of manual annotations, although only one embryologist participated in this task.
Wider implications of the findings: The dynamics of vitrified/warmed blastocysts prior to embryo transfer could be more relevant variables than the morphological quality on day 5 before the cryopreservation. The analysis of embryo behavior after warming could improve clinical outcomes in frozen embryo transfers.
Trial registration number
none
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Affiliation(s)
- L Alegre
- Instituto Valenciano de Infertilidad IVI, In Vitro Fertilization, Valencia, Spain
| | - L Bori
- Instituto Valenciano de Infertilidad IVI, In Vitro Fertilization, Valencia, Spain
| | - A Coello
- Instituto Valenciano de Infertilidad IVI, In Vitro Fertilization, Valencia, Spain
| | - A S Ferreira
- Universidade Estadual Paulista, Research department, Sao Paulo, Brazil
| | - J C Rocha
- Universidade Estadual Paulista, Research department, Sao Paulo, Brazil
| | - A Cobo
- Instituto Valenciano de Infertilidad IVI, In Vitro Fertilization, Valencia, Spain
| | - M Meseguer
- Instituto Valenciano de Infertilidad IVI, In Vitro Fertilization, Valencia, Spain
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Palugan MJA, Assis ACB, Bessa EJC, Ferreira AS, Lopes AJ. Predictors of functional capacity as measured by the Glittre activities of daily living test in women with rheumatoid arthritis. ACTA ACUST UNITED AC 2021; 54:e10040. [PMID: 33729387 PMCID: PMC7959171 DOI: 10.1590/1414-431x202010040] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2020] [Accepted: 12/18/2020] [Indexed: 08/19/2023]
Abstract
Although pulmonary involvement is the most common extra-articular manifestation of rheumatoid arthritis (RA), traditional pulmonary function tests (PFTs) do not show a good correlation with the field tests usually performed in these patients. In recent decades, measurement of ventilation distribution heterogeneity through the nitrogen single-breath washout (N2SBW) test and evaluation of functional capacity during exercise using the Glittre activities of daily living test (GA-T) have been increasingly used. Therefore, the objective of this study was to evaluate predictors of GA-T outcomes in women with RA considering demographic, anthropometric, clinical, functional variables, and chest computed tomography (CT) findings. Forty-three women with RA underwent the GA-T, the N2SBW test, spirometry, measurement of the diffusing capacity for carbon monoxide (DLco), measurement of respiratory muscle strength, and evaluation of physical function of the lower and upper limbs through the Health Assessment Questionnaire Disability Index (HAQ-DI). Chest CT scans were analyzed retrospectively. The GA-T time showed significant correlations with the DLco (rs=-0.397, P=0.008), forced vital capacity/DLco (rs=0.307, P=0.044), phase III slope of the N2SBW test (SIIIN2, rs=0.644, P<0.0001), and the HAQ-DI (rs=0.482, P=0.001). Disease extent as assessed by chest CT was associated with the GA-T time. On multiple regression analysis, the SIIIN2 and HAQ-DI were the only predictors of the GA-T time, explaining 40% of its variability. Thus, ventilation distribution heterogeneity and worse physical function substantially explain the variability in GA-T time in women with RA and varying extents of disease on chest CT.
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Affiliation(s)
- M J A Palugan
- Programa de Pós-Graduação em Ciências da Reabilitação, Centro Universitário Augusto Motta, Rio de Janeiro, RJ, Brasil
| | - A C B Assis
- Programa de Pós-Graduação em Ciências da Reabilitação, Centro Universitário Augusto Motta, Rio de Janeiro, RJ, Brasil
| | - E J C Bessa
- Programa de Pós-Graduação em Ciências Médicas, Faculdade de Ciências Médicas, Universidade do Estado do Rio de Janeiro, Rio de Janeiro, RJ, Brasil
| | - A S Ferreira
- Programa de Pós-Graduação em Ciências da Reabilitação, Centro Universitário Augusto Motta, Rio de Janeiro, RJ, Brasil
| | - A J Lopes
- Programa de Pós-Graduação em Ciências da Reabilitação, Centro Universitário Augusto Motta, Rio de Janeiro, RJ, Brasil.,Programa de Pós-Graduação em Ciências Médicas, Faculdade de Ciências Médicas, Universidade do Estado do Rio de Janeiro, Rio de Janeiro, RJ, Brasil
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Oliveira JVLC, Ferreira AS, Zeppelini D. Two new species of Collembola (Arthropoda: Hexapoda) from Minas Gerais, Brazil. Neotrop Entomol 2020; 49:420-434. [PMID: 32399957 DOI: 10.1007/s13744-020-00769-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/17/2019] [Accepted: 02/27/2020] [Indexed: 06/11/2023]
Abstract
Two new species of Collembola are described, full body chaetotaxy is given. Ptenothrix dalii sp. nov. and Seira pietata sp. nov. were originally found in metalogenic areas covered with transitional vegetation of savanna and forest in Minas Gerais, Southeastern Brazil. Ptenothrix dalii sp. nov. is part of the "gracilis-group" of species, with large, blunt macrochaetae on head and body. Seira pietata sp. nov. is part of the "andensis-group" of species, lacking macrochaeta on abdominal segment I.
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Affiliation(s)
- J V L C Oliveira
- Programa de Pós-Graduação em Ciências Biológicas (Zoologia). Centro de Ciências Exatas e da Natureza, Univ Federal da Paraíba, Campus I, João Pessoa, Paraíba, Brasil.
- Lab de Sistemática de Collembola e Conservação. Depto de Biologia, Centro de Ciências Biológicas e Sociais Aplicadas, Univ Estadual da Paraíba, Campus V, João Pessoa, Paraíba, Brasil.
| | - A S Ferreira
- Lab de Sistemática de Collembola e Conservação. Depto de Biologia, Centro de Ciências Biológicas e Sociais Aplicadas, Univ Estadual da Paraíba, Campus V, João Pessoa, Paraíba, Brasil
| | - D Zeppelini
- Programa de Pós-Graduação em Ciências Biológicas (Zoologia). Centro de Ciências Exatas e da Natureza, Univ Federal da Paraíba, Campus I, João Pessoa, Paraíba, Brasil
- Lab de Sistemática de Collembola e Conservação. Depto de Biologia, Centro de Ciências Biológicas e Sociais Aplicadas, Univ Estadual da Paraíba, Campus V, João Pessoa, Paraíba, Brasil
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Simmi FZ, Dallagnol LJ, Ferreira AS, Pereira DR, Souza GM. Electrome alterations in a plant-pathogen system: Toward early diagnosis. Bioelectrochemistry 2020; 133:107493. [PMID: 32145516 DOI: 10.1016/j.bioelechem.2020.107493] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2019] [Revised: 02/19/2020] [Accepted: 02/19/2020] [Indexed: 01/06/2023]
Abstract
This work aimed to verify the existence of patterns on the electrophysiological systemic responses of tomato plants inoculated with a pathogenic fungus in an environment with controlled light and temperature. Electrical signalling was measured before and after inoculation in the same plants, and data were analysed with time series techniques and approximate multi-scale entropy (ApEn). Machine learning algorithms were utilised in order to classify data before and after infection throughout the five days of experiments. The obtained results have shown that it is possible to distinguish differences in the plant's electrome activity before and after the fungus inoculation. In some cases, we have found scale invariance quantified by the power law decay in the distribution histogram. We also found a higher degree of internal organisation quantified by ApEn. The results of the classification algorithms achieved higher accuracy of infection detection at the initial stage of pathogen recognition by the plant. Besides, this study showed evidence that long-distance electrical signalling is likely involved in the plant-pathogen interaction, since signals were obtained in the stem and the inoculum applied on the plant leaves. This might be useful for the early detection of plant infections.
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Affiliation(s)
- F Z Simmi
- Federal University of Pelotas, Post-Graduation Programme on Plant Physiology, Institute of Biology, Department of Botany, Pelotas, RS, Brazil.
| | - L J Dallagnol
- Federal University of Pelotas, Crop Protection Graduate Program, Faculty of Agronomy Eliseu Maciel, Department of Crop Protection, Pelotas, RS, Brazil
| | - A S Ferreira
- Federal University of Pelotas, Department of Physics, Pelotas, RS, Brazil
| | - D R Pereira
- University of Western São Paulo, Machine Intelligence Laboratory, Presidente Prudente, SP, Brazil
| | - G M Souza
- Federal University of Pelotas, Post-Graduation Programme on Plant Physiology, Institute of Biology, Department of Botany, Pelotas, RS, Brazil
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Campos I, Costa-Oliveira C, Medeiros P, Marques Pires C, Flores R, Ferreira AS, Galvao Braga C, Costa J, Vieira C, Marques J. P5521Door-to-balloon time and mortality of a PCI centre: how crucial can 30 minutes be for our STEMI patients? Eur Heart J 2019. [DOI: 10.1093/eurheartj/ehz746.0469] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Abstract
Introduction
STEMI time delays have been presented as an indicator of quality of care. Considering the system delay, the guidelines of European Society of Cardiology (ESC) and American Heart Association (AHA) for the management of STEMI patients (pts) diverge regarding the maximum time from STEMI diagnosis to wire crossing in pts presenting at primary PCI (pPCI) hospitals (≤60min versus ≤90min, respectively).
Objective
To compare the prognosis between pts presenting at pPCI hospital with maximum time from STEMI diagnosis to wire crossing of ≤60min and patients with times between 61 and 90min.
Methods
The records of 1679 STEMI pts admitted consecutively in our coronary care unit during six years were analysed retrospectively. Of this pts, 341 (20%) were admitted directly in a PCI centre and 1338 (80%) were rescued by an emergency medical system or presented to a non-PCI centre. Pts that presented at PCI centre were divided into two groups: group 1 – STEMI pts with maximum time from STEMI diagnosis to wire crossing of ≤60min (n=202,69%); group 2 – STEMI pts with times 61–90 min (n=91,31%). Pts with time from STEMI diagnosis to wire crossing >90min were excluded. Primary endpoints were the occurrence of death at 6 months and 1 year; follow-up was completed in 98% of pts.
Results
Group 2 pts were older (60±14 vs 67±143, p<0.001), with higher proportion of women (14.9% vs 25.3%; p=0.026), hypertension (45.5% vs 61.5%, p=0.035), diabetes (17.1 vs 24.4%, p=0.005) and presented more frequently Killip 4 at admission (2.1% vs 12.5%, p=0.003). Group 1 pts had higher proportion of smokers (62.2% vs 49.4%, p=0.03). Patient delay was statistically higher in group 2 (Mdn (h) 3.8±3.5 vs 5±2, p<0.001), as was the system delay (Mdn (min) 45±9 vs 74±8, p<0.001). In-hospital mortality (3.8% vs 5.1%, p=0.42) wasn't different between groups, but at 1-month (3.8% vs 10.3%, p=0.05), 6-months (4.4% vs 12.8%, p=0.02) and 1-year mortality (5% vs 15.4%, p=0.008) was higher in group 2. In multivariate analysis and after adjusting for different baseline characteristics, pts who complied with the recommended times according to the 2017 ESC guidelines had lower risk mortality at 1 year compared to group 2 [HR 0.42, 95% CI (0.23–0.74), p=0.006].
Conclusion
In patients presenting at this PCI centre, complying with the 2017 ESC STEMI guidelines in order to reduce the system delay to ≤60min was crucial, since pts who were reperfused within this recommended time had lower mortality rates.
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Affiliation(s)
- I Campos
- Hospital de Braga, Cardiology, Braga, Portugal
| | | | - P Medeiros
- Hospital de Braga, Cardiology, Braga, Portugal
| | | | - R Flores
- Hospital de Braga, Cardiology, Braga, Portugal
| | | | | | - J Costa
- Hospital de Braga, Cardiology, Braga, Portugal
| | - C Vieira
- Hospital de Braga, Cardiology, Braga, Portugal
| | - J Marques
- Hospital de Braga, Cardiology, Braga, Portugal
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Lopes AJ, Vigário PS, Hora AL, Deus CA, Soares MS, Guimaraes FS, Ferreira AS. Ventilation distribution, pulmonary diffusion and peripheral muscle endurance as determinants of exercise intolerance in elderly patients with chronic obstructive pulmonary disease. Physiol Res 2018; 67:863-874. [PMID: 30204461 DOI: 10.33549/physiolres.933867] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Abstract
Chronic obstructive pulmonary disease (COPD) is a progressive and disabling disease that has been associated with aging. Several factors may potentially impair performance during exercise in elderly patients with COPD. This study was conducted to evaluate what characteristics related to lung function, peripheral muscle strength and endurance can predict the performance of elderly patients with COPD during cardiopulmonary exercise testing (CPET). Forty elderly patients with COPD underwent resting lung function tests, knee isokinetic dynamometry, and CPET. Three models were developed to explain the variability in peak oxygen uptake (VO(2) peak) after controlling for age as an independent confounder. The pulmonary function model showed the highest explained variance (65.6 %); in this model, ventilation distribution (p<0.001) and pulmonary diffusion (0.013) were found to be independent predictors. Finally, the models that included the muscle strength and endurance variables presented explained variances of 51 % and 57.4 %, respectively. In these models that involved muscular dysfunction, however, only the endurance variables were found to be independent predictors (p<0.05). In conclusion, ventilation distribution and pulmonary diffusion, but not the degree of airway obstruction, independently predict CPET performance in elderly patients with COPD. In addition, peripheral muscle endurance, but not strength, also predicts CPET performance in these subjects.
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Affiliation(s)
- A J Lopes
- Rehabilitation Sciences Post-Graduation Program, Augusto Motta University Center, Rio de Janeiro, Brazil.
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Duraes Campos I, Ferreira AS, Galvao Braga C, Costa J, Quina Rodrigues C, Oliveira C, Rodrigues C, Medeiros P, Vieira C, Marques J. P3183Does complying guidelines matter? Eur Heart J 2018. [DOI: 10.1093/eurheartj/ehy563.p3183] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Affiliation(s)
| | - A S Ferreira
- University of Minho, School of Medicine, Braga, Portugal
| | | | - J Costa
- Hospital de Braga, Cardiology, Braga, Portugal
| | | | - C Oliveira
- Hospital de Braga, Cardiology, Braga, Portugal
| | - C Rodrigues
- Hospital de Braga, Cardiology, Braga, Portugal
| | - P Medeiros
- Hospital de Braga, Cardiology, Braga, Portugal
| | - C Vieira
- Hospital de Braga, Cardiology, Braga, Portugal
| | - J Marques
- Hospital de Braga, Cardiology, Braga, Portugal
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Esteves F, Cruz R, Vasconcelos-Nóbrega C, Santos C, Ferreira AS, Petrovic T, Cardoso L, Coelho AC, Vala H, Nascimento MSJ, Mesquita JR. Serologic evidence for Schmallenberg virus circulation at high altitude, Central Portugal, 2015-2016. Transbound Emerg Dis 2018; 65:1553-1556. [DOI: 10.1111/tbed.12899] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2018] [Indexed: 01/08/2023]
Affiliation(s)
- F. Esteves
- Centre for Studies in Education and Health Technologies (CI&DETS); Agrarian School of Viseu; Polytechnic Institute of Viseu; Viseu Portugal
| | - R. Cruz
- Centre for Studies in Education and Health Technologies (CI&DETS); Agrarian School of Viseu; Polytechnic Institute of Viseu; Viseu Portugal
| | - C. Vasconcelos-Nóbrega
- Centre for Studies in Education and Health Technologies (CI&DETS); Agrarian School of Viseu; Polytechnic Institute of Viseu; Viseu Portugal
- Centre for the Research and Technology of Agro-Environmental and Biological Sciences (CITAB); University of Trás-os-Montes e Alto Douro; Vila Real Portugal
| | - C. Santos
- Centre for Studies in Education and Health Technologies (CI&DETS); Agrarian School of Viseu; Polytechnic Institute of Viseu; Viseu Portugal
| | - A. S. Ferreira
- Laboratory of Microbiology; Department of Biological Sciences; Faculty of Pharmacy; University of Porto; Porto Portugal
| | - T. Petrovic
- Scientific Veterinary Institute “Novi Sad”; Novi Sad Serbia
| | - L. Cardoso
- Animal and Veterinary Research Centre (CECAV); University of Trás-os-Montes e Alto Douro; Vila Real Portugal
| | - A. C. Coelho
- Centre for the Research and Technology of Agro-Environmental and Biological Sciences (CITAB); University of Trás-os-Montes e Alto Douro; Vila Real Portugal
| | - H. Vala
- Centre for Studies in Education and Health Technologies (CI&DETS); Agrarian School of Viseu; Polytechnic Institute of Viseu; Viseu Portugal
- Centre for the Research and Technology of Agro-Environmental and Biological Sciences (CITAB); University of Trás-os-Montes e Alto Douro; Vila Real Portugal
| | - M. S. J. Nascimento
- Laboratory of Microbiology; Department of Biological Sciences; Faculty of Pharmacy; University of Porto; Porto Portugal
- Epidemiology Research Unit (EPIUnit); Institute of Public Health; University of Porto; Porto Portugal
| | - J. R. Mesquita
- Centre for Studies in Education and Health Technologies (CI&DETS); Agrarian School of Viseu; Polytechnic Institute of Viseu; Viseu Portugal
- Epidemiology Research Unit (EPIUnit); Institute of Public Health; University of Porto; Porto Portugal
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12
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Saraiva GFR, Ferreira AS, Souza GM. Osmotic stress decreases complexity underlying the electrophysiological dynamic in soybean. Plant Biol (Stuttg) 2017; 19:702-708. [PMID: 28449392 DOI: 10.1111/plb.12576] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/19/2017] [Accepted: 04/11/2017] [Indexed: 05/19/2023]
Abstract
Studies on plant electrophysiology are mostly focused on specific traits of single cells. Inspired by the complexity of the signalling network in plants, and by analogy with neurons in human brains, we sought evidence of high complexity in the electrical dynamics of plant signalling and a likely relationship with environmental cues. An EEG-like standard protocol was adopted for high-resolution measurements of the electrical signal in Glycine max seedlings. The signals were continuously recorded in the same plants before and after osmotic stimuli with a -2 MPa mannitol solution. Non-linear time series analyses methods were used as follows: auto-correlation and cross-correlation function, power spectra density function, and complexity of the time series estimated as Approximate Entropy (ApEn). Using Approximate Entropy analysis we found that the level of temporal complexity of the electrical signals was affected by the environmental conditions, decreasing when the plant was subjected to a low osmotic potential. Electrical spikes observed only after stimuli followed a power law distribution, which is indicative of scale invariance. Our results suggest that changes in complexity of the electrical signals could be associated with water stress conditions in plants. We hypothesised that the power law distribution of the spikes could be explained by a self-organised critical state (SOC) after osmotic stress.
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Affiliation(s)
- G F R Saraiva
- Graduate Program in Agronomy, Western São Paulo University, (PPGA/UNOESTE), Presidente Prudente, Brazil
| | - A S Ferreira
- Department of Physics, Federal University of Pelotas (IFM/UFPel), Pelotas, Brazil
| | - G M Souza
- Department of Botany, Federal University of Pelotas (IB/UFPel), Pelotas, Brazil
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13
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Ferreira APA, Póvoa LC, Zanier JFC, Machado DC, Ferreira AS. Sensitivity for palpating lumbopelvic soft- tissues and bony landmarks and its associated factors: A single-blinded diagnostic accuracy study. J Back Musculoskelet Rehabil 2017; 30:735-744. [PMID: 28453451 DOI: 10.3233/bmr-150356] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
BACKGROUND Evidence on the diagnostic performance of palpatory methods and possible confounding factors is scarce. OBJECTIVES To examine the sensitivity of palpatory methods for location of lumbopelvic landmarks and to assess its association with personal characteristics. METHODS Eighty-three participants (41 men, 55.6 (16.5) years, 25.9 (4.8) kg/m2 [mean (SD)]) were enrolled in this single-blinded study. Fourteen body and softy-tissue landmarks were sequentially palpated from the spinous process of L4 to the ischial tuberosity. CT-scan images were used to assess what landmark was located. RESULTS Sensitivity for location was in range 22-86% for soft-tissues and 26-69% for bony landmarks. Reduction in sensitivity was observed from the quadratus lumborum to the inferior and lateral angle of the sacrum (86-26% and 75-33%, left and right sides, respectively). Palpations of L4 and L5 spinous processes were systematically more cephalic than other landmarks. Gender was weakly correlated to almost all landmarks (rpb= 0.333 or weaker). Body mass index was weakly correlated to the accurate location of ILAS and quadratus lumborum, great trochanter, PSIS, and piriformis (rpb=-0.307 or weaker). CONCLUSIONS Systematic and propagation errors were present using sequential palpatory methods. Palpation in men was more sensitive and higher BMI was associated with lower sensitivity for lumbopelvic landmarks.
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Affiliation(s)
- A P A Ferreira
- Instituto Brasileiro de Osteopatia, Centro, CEP 22440-901, RJ, Brasil.,Programa de Pós-graduação em Ciências da Reabilitação, Centro Universitário Augusto Motta, Bonsucesso, CEP 21041-010, RJ, Brasil
| | - L C Póvoa
- Instituto Brasileiro de Osteopatia, Centro, CEP 22440-901, RJ, Brasil.,Programa de Pós-graduação em Ciências da Reabilitação, Centro Universitário Augusto Motta, Bonsucesso, CEP 21041-010, RJ, Brasil
| | - J F C Zanier
- Hospital Universitário Pedro Ernesto, Universidade do Estado do Rio de Janeiro, Vila Isabel, CEP 20551-030, RJ, Brasil
| | - D C Machado
- Hospital Universitário Pedro Ernesto, Universidade do Estado do Rio de Janeiro, Vila Isabel, CEP 20551-030, RJ, Brasil
| | - A S Ferreira
- Programa de Pós-graduação em Ciências da Reabilitação, Centro Universitário Augusto Motta, Bonsucesso, CEP 21041-010, RJ, Brasil
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14
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Santos PBR, Vigário PS, Mainenti MRM, Ferreira AS, Lemos T. Seated limits-of-stability of athletes with disabilities with regard to competitive levels and sport classification. Scand J Med Sci Sports 2017; 27:2019-2026. [PMID: 28150870 DOI: 10.1111/sms.12847] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/26/2017] [Indexed: 12/01/2022]
Abstract
In this study, we asked whether wheelchair rugby (WR) classification and competitive level influence trunk function of athletes with disabilities, in terms of seated limits-of-stability (LoS). Twenty-eight athletes were recruited from international- and national-level WR teams, with each group exhibiting marked differences in years of sports practice and training volume. Athletes were also distributed into three groups according their classification: low-point (0.5-1.5-point); mid-point (2.0-2.5-point); and high-point (3.0-3.5-point). Athletes were asked to sit on a force platform and to lean the body as far as possible in eight predefined directions. Center of pressure (COP) coordinates were calculated from the ground reaction forces acquired with the force platform. LoS were computed as the area of ellipse adjusted to maximal COP excursion achieved for the eight directions. ANOVAs reveal that LoS were not different when international- and national-level players were compared (P=.744). Nevertheless, LoS were larger in players from the high-point group than from the low-point group (P=.028), with the mid-point group being not different from both (P>.194). In summary, (i) competitive level does not impact LoS measures and (ii) LoS are remarkably distinct when comparing both extremes of the WR classification range. Our results suggest that, as a training-resistant measure, LoS could be a valid assessment of trunk impairment, potentially contributing to the development of an evidence-based WR classification.
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Affiliation(s)
- P B R Santos
- Programa de Pós-Graduação em Ciências da Reabilitação, Centro Universitário Augusto Motta - UNISUAM, Rio de Janeiro, Brasil
| | - P S Vigário
- Programa de Pós-Graduação em Ciências da Reabilitação, Centro Universitário Augusto Motta - UNISUAM, Rio de Janeiro, Brasil
| | - M R M Mainenti
- Divisão de Pesquisa e Extensão, Escola de Educação Física do Exército (EsEFEx), Rio de Janeiro, Brasil
| | - A S Ferreira
- Programa de Pós-Graduação em Ciências da Reabilitação, Centro Universitário Augusto Motta - UNISUAM, Rio de Janeiro, Brasil
| | - T Lemos
- Programa de Pós-Graduação em Ciências da Reabilitação, Centro Universitário Augusto Motta - UNISUAM, Rio de Janeiro, Brasil
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15
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Oliveira GM, Ferreira AS, Campos PF, Rodrigues VV, Silva FCO, Santos WG, Lima AL, Rodrigues PG, Lopes CC. Digestible tryptophan to lysine ratios for weaned piglets at 26 days of age. Anim Prod Sci 2017. [DOI: 10.1071/an15504] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
With the objective of determining the optimal digestible tryptophan to lysine ratios (Trp : Lys) in feed, 192 crossbred piglets were weaned at 26.3 ± 2.0 days, with initial weights of 8 ± 0.360 kg. The piglets were blocked by bodyweight and randomly allotted into six treatments, eight repetitions and four piglets per experimental unit. The treatments included five ratios of digestible Trp : Lys of 0.15, 0.17, 0.19, 0.21 and 0.23 with 1.26% digestible lysine and one positive control treatment (C+) with a Trp : Lys ratio of 0.19 and digestible lysine of 1.33%. The piglet’s performance and other characteristics were evaluated in phases: Phase I lasted from weaning up to Day 14 of the experiment, and Phase II lasted from weaning up to Day 21 of the experiment. The feed intake during Phase I, including the protein and fat deposition rates, the kidney relative weights and carcass yield were not influenced by the Trp : Lys ratios (P > 0.05). The Trp : Lys ratios had a linear effect on the liver and kidney absolute weights (P < 0.05). The ratio also had a linear effect (P < 0.01) on the bodyweight, the average daily gain, the gain : feed ratio of the piglets during Phases I and II and on the feed intake during Phase II (P < 0.05). The effect of the Trp : Lys ratios on the digestible lysine level (P = 0.04) demonstrated that digestible lysine was a limiting factor. The Linear Response Plateau model indicated that the best Trp : Lys ratio (P = 0.04) was 0.20 during Phase I and 0.22 (P < 0.01) during Phase II. Thus, the optimal digestible Trp : Lys ratio for piglets during the initial growth phase (from 26 to 47 days of age) is 0.22.
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16
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Pereira SG, Rosa AC, Ferreira AS, Moreira LM, Proença DN, Morais PV, Cardoso O. Virulence factors and infection ability of Pseudomonas aeruginosa isolates from a hydropathic facility and respiratory infections. J Appl Microbiol 2014; 116:1359-68. [PMID: 24484457 DOI: 10.1111/jam.12463] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2013] [Revised: 01/17/2014] [Accepted: 01/27/2014] [Indexed: 11/27/2022]
Abstract
AIMS To compare the virulence pool and acute infection ability of Pseudomonas aeruginosa isolates from a hydropathic facility, used to treat respiratory conditions by inhalation of untreated natural mineral water, with clinical isolates from respiratory infections. METHODS AND RESULTS Pseudomonas aeruginosa isolates from a hydropathic facility and from respiratory infections were typed by pulsed-field gel electrophoresis. Nonclonal representatives of each population were selected. 18 virulence-encoding genes were screened by polymerase chain reaction and statistically compared by multiple correspondence analysis. Homogeneous distribution of genes between populations but higher genetic association in aquatic isolates was observed, as well as distinct virulence pool according to location in the water system. Acute infection ability of selected isolates from each population, in Galleria mellonella model, showed lower LD50 of the majority of the hydropathic isolates and significant variations in LD50 of biofilm isolates from different equipments. CONCLUSIONS Hydrotherapy Ps. aeruginosa isolates present similar virulence to isolates from respiratory infections. Hydrotherapy users may be exposed to different microbiological risks when using different treatment equipments. SIGNIFICANCE AND IMPACT OF THE STUDY Twenty-one million people use hydropathic facilities in Europe, and the majority present risk factors to pneumonia. This study demonstrates the health risk associated with this practice. Revision of European regulations should be considered.
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Affiliation(s)
- S G Pereira
- Center for Pharmaceutical Studies, Faculty of Pharmacy, University of Coimbra, Coimbra, Portugal
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17
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Cressoni JC, Viswanathan GM, Ferreira AS, da Silva MAA. Alzheimer random walk model: two previously overlooked diffusion regimes. Phys Rev E Stat Nonlin Soft Matter Phys 2012; 86:042101. [PMID: 23214629 DOI: 10.1103/physreve.86.042101] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/03/2012] [Indexed: 06/01/2023]
Abstract
A non-Markovian one-dimensional random walk model is studied with emphasis on the phase-diagram, showing all the diffusion regimes, along with the exactly determined critical lines. The model, known as the Alzheimer walk, is endowed with memory-controlled diffusion, responsible for the model's long-range correlations, and is characterized by a rich variety of diffusive regimes. The importance of this model is that superdiffusion arises due not to memory per se, but rather also due to loss of memory. The recently reported numerically and analytically estimated values for the Hurst exponent are hereby reviewed. We report the finding of two, previously overlooked, phases, namely, evanescent log-periodic diffusion and log-periodic diffusion with escape, both with Hurst exponent H=1/2. In the former, the log-periodicity gets damped, whereas in the latter the first moment diverges. These phases further enrich the already intricate phase diagram. The results are discussed in the context of phase transitions, aging phenomena, and symmetry breaking.
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Affiliation(s)
- J C Cressoni
- Departamento de Física e Química, FCFRP, Universidade de São Paulo, 14040-903 Ribeirão Preto, SP, Brazil
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18
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Cressoni JC, Viswanathan GM, Ferreira AS, da Silva MAA. Weakly anomalous diffusion with non-Gaussian propagators. Phys Rev E Stat Nonlin Soft Matter Phys 2012; 86:022103. [PMID: 23005807 DOI: 10.1103/physreve.86.022103] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/06/2012] [Indexed: 06/01/2023]
Abstract
A poorly understood phenomenon seen in complex systems is diffusion characterized by Hurst exponent H ≈ 1/2 but with non-Gaussian statistics. Motivated by such empirical findings, we report an exact analytical solution for a non-Markovian random walk model that gives rise to weakly anomalous diffusion with H = 1/2 but with a non-Gaussian propagator.
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Affiliation(s)
- J C Cressoni
- Departamento de Física e Química, FCFRP, Universidade de São Paulo, Ribeirão Preto, SP 14040-903, Brazil
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19
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Sa PM, Faria AD, Ferreira AS, Lopes AJ, Jansen JM, Melo PL. Validation of the Forced Oscillation Technique in the diagnostic of respiratory changes in patients with silicosis. Annu Int Conf IEEE Eng Med Biol Soc 2011; 2010:398-401. [PMID: 21096531 DOI: 10.1109/iembs.2010.5627284] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Silicosis is a typical occupational respiratory disease characterized by irreversible alterations throughout the alveolar and interstitial structure. The objectives of this study were (1) investigate the potential of the Forced Oscillation Technique (FOT) in the analysis of the patients with silicosis, and (2) evaluate the ability of FOT to identify early alterations in the respiratory mechanics of these patients. Sixty-one volunteers were analyzed: 20 healthy subjects and 41 with silicosis; these, were divided into 4 groups according to spirometric results: normal spirometric exam (n = 11); mild obstruction (n = 20); moderate and severe obstruction (n = 10.). A significant (p〈0.0001) increase in total resistance (R0) and mean resistance (Rm) were observed, as well as a decrease in the dynamic compliance (p〈0.0003) and mean reactance (p〈0.000004). R0 and Rm obtained adequate accuracy for clinical use (>80%). FOT parameters adequately described the pathophysiological changes associated with silicosis and presented adequate accuracy for clinical use, indicating that this technique can be helpful in the evaluation respiratory mechanics in this disease.
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Affiliation(s)
- P M Sa
- Biomedical Instrumentation Laboratory, Institute of Biology, Faculty of Engineering, State University of Rio de Janeiro, Brazil.
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20
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Martins ML, Ferreira AS, Sampaio A, Vieira R, Inácio J. Direct and specific identification of Cryptococcus neoformans in biological samples using fluorescently labelled DNA probes. Eur J Clin Microbiol Infect Dis 2010; 29:571-6. [PMID: 20221657 DOI: 10.1007/s10096-010-0897-z] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2009] [Accepted: 02/16/2010] [Indexed: 11/24/2022]
Abstract
Fluorescence in situ hybridisation (FISH) is a suitable technique for the rapid, reliable and cultivation-independent identification of microbial pathogens. This study describes the development of fluorescently labelled rRNA-targeted oligonucleotides and a FISH assay to detect and identify Cryptococcus neoformans in culture and biological samples. All C. neoformans reference and clinical isolates gave positive signals with the specific oligonucleotide probes, whereas all non-target yeast species gave negative reactions with the same probes. The assay was also successfully applied to the detection of C. neoformans cells in cerebrospinal samples from patients with clinical diagnosis of cryptococcosis. The described FISH-based assay revealed to be practical, sensitive and specific for the detection and identification of C. neoformans yeasts.
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Affiliation(s)
- M L Martins
- Instituto de Higiene e Medicina Tropical, Universidade Nova de Lisboa, 1349-008 Lisboa, Portugal.
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21
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Ferreira AS, Cressoni JC, Viswanathan GM, Alves da Silva MA. Anomalous diffusion in non-Markovian walks having amnestically induced persistence. Phys Rev E Stat Nonlin Soft Matter Phys 2010; 81:011125. [PMID: 20365341 DOI: 10.1103/physreve.81.011125] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/03/2009] [Indexed: 05/29/2023]
Abstract
We report numerically and analytically estimated values for the Hurst exponent for a recently proposed non-Markovian walk characterized by amnestically induced persistence. These results are consistent with earlier studies showing that log-periodic oscillations arise only for large memory losses of the recent past. We also report numerical estimates of the Hurst exponent for non-Markovian walks with diluted memory. Finally, we study walks with a fractal memory of the past for a Thue-Morse and Fibonacci memory patterns. These results are interpreted and discussed in the context of the necessary and sufficient conditions for the central limit theorem to hold.
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Affiliation(s)
- A S Ferreira
- Instituto de Física, Universidade Federal de Alagoas, Maceió 57072-970, AL, Brazil
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22
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Castro-Costa CM, Campos-Araújo AQ, Câmara CC, Ferreira AS, Santos TJT, Castro-Costa SB, Acântara RNM, Taylor GP. Pain in tropical spastic paraparesis: HTLV-I associated myelopathy patients. Arq Neuro-Psiquiatr 2009. [DOI: 10.1590/s0004-282x2009000600042] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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Ferreira AS. Prophylactic effects of short-term acupuncture on Zusanli (ST36) in Wistar rats with lipopolysaccharide-induced acute lung injury. ACTA ACUST UNITED AC 2009; 7:969-75. [DOI: 10.3736/jcim20091011] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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da Silva MAA, Viswanathan GM, Ferreira AS, Cressoni JC. Spontaneous symmetry breaking in amnestically induced persistence. Phys Rev E Stat Nonlin Soft Matter Phys 2008; 77:040101. [PMID: 18517569 DOI: 10.1103/physreve.77.040101] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/11/2007] [Revised: 01/28/2008] [Indexed: 05/26/2023]
Abstract
We investigate a recently proposed non-Markovian random walk model characterized by loss of memories of the recent past and amnestically induced persistence. We report numerical and analytical results showing the complete phase diagram, consisting of four phases, for this system: (i) classical nonpersistence, (ii) classical persistence, (iii) log-periodic nonpersistence, and (iv) log-periodic persistence driven by negative feedback. The first two phases possess continuous scale invariance symmetry, however, log-periodicity breaks this symmetry. Instead, log-periodic motion satisfies discrete scale invariance symmetry, with complex rather than real fractal dimensions. We find for log-periodic persistence evidence not only of statistical but also of geometric self-similarity.
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Ferreira AS, Filho JB, Souza MN. Simplified distributed-parameter model of brachial-radial arteries for noninvasive determination of mechanical characteristics of vessel. Conf Proc IEEE Eng Med Biol Soc 2006; 2006:1814-1817. [PMID: 17945669 DOI: 10.1109/iembs.2006.260102] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
This paper proposes a simplified distributed-parameter model of the brachial-radial arteries segment for the determination of mechanical parameters of these arteries and compares it with a four-element Windkessel model. The comparison is performed using data collected noninvasively of pressure pulse waveforms at two different locations of the arterial segment, under physiological (normotensive) and pathological (primary hypertension) conditions. The results show, by Akaike Information Criterion, that the proposed model fits the real pressure pulse waveform better than classical Windkessel model, and that also gives mechanical parameters coherent with the clinical condition.
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Affiliation(s)
- A S Ferreira
- Biomed. Eng. Program, Univ. Fed. do Rio de Janeiro, Rio de Janeiro, Brazil
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Dias-Cabral AC, Ferreira AS, Phillips J, Queiroz JA, Pinto NG. The effects of ligand chain length, salt concentration and temperature on the adsorption of bovine serum albumin onto polypropyleneglycol-Sepharose. Biomed Chromatogr 2005; 19:606-16. [PMID: 15803451 DOI: 10.1002/bmc.487] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
The interaction thermodynamics associated with bovine serum albumin adsorption on polypropylene glycol (n=3)-Sepharose CL-6B and polypropylene glycol (n=7)-Sepharose CL-6B, using ammonium sulfate as the modulator was studied. Analysis of data under linear conditions was accomplished with the stoichiometric displacement retention model, preferential interaction approach and van't Hoff plots applied to HIC systems. Preferential interaction analysis indicated a strong entropic driving force under linear conditions, due to the release of a large amount of solvent on adsorption. In contrast, flow microcalorimetry under overloaded conditions showed that the adsorption of bovine serum albumin may be entropically or enthalpically driven. It is postulated that adsorption in the nonlinear region is influenced by the degree of water release, protein-protein interactions on the surface, reorientation of ligand, and conformational changes in the protein.
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Affiliation(s)
- A C Dias-Cabral
- Health Sciences Research Center, University of Beira Interior, 6201-001 Covilhã, Portugal
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27
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Ferreira AS, Santos MAR, Barbosa Filho J, Cordovil I, Souza MN. Determination of radial artery compliance can increase the diagnostic power of pulse wave velocity measurement. Physiol Meas 2004; 25:37-50. [PMID: 15005303 DOI: 10.1088/0967-3334/25/1/004] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Pulse wave velocity (PWV) is an indicator associated with the arterial stiffness. Although this technique has been used in the diagnosis of systemic arterial hypertension (SAH), it cannot supply alone enough information about the pathogenesis of this disturbance. This paper aims to determine the compliance of brachial-radial arterial segment by applying a three-element windkessel model, and by using the same pressure waveforms acquired to calculate the PWV. The proposed method to determine the arterial compliance was evaluated with a physical simulation of the arterial system, where parameters were known, resulting in an estimation error of 0.73 x 10(-7) cm5 dyne(-1). In a clinical study the estimated compliance was statistically different (p < 0.01) in a controlled group ((3.12 +/- 3.53) x 10(-7) cm5 dyne(-1)) and in an SAH group ((1.04 +/- 0.74) x 10(-7) cm5 dyne(-1)). It was observed that the PWV value calculated using the maximum of the first derivative of the pressure waveform upstroke as characteristic points was the best correlated (r = -0.71) with the determined compliance. Because SAH normally results, among other causes. from a decreased arterial compliance the results suggest that the determined compliance could be used concomitantly with PWV to supply more diagnostic information about the pathogenesis of SAH.
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Affiliation(s)
- A S Ferreira
- Biomedical Engineering Program, Federal University of Rio de Janeiro, PO Box 68510, CEP: 21945-970, Rio de Janeiro, RJ, Brazil
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Ferreira AS, da Silva MAA, Cressoni JC. Stochastic modeling approach to the incubation time of prionic diseases. Phys Rev Lett 2003; 90:198101. [PMID: 12785987 DOI: 10.1103/physrevlett.90.198101] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/27/2003] [Indexed: 05/24/2023]
Abstract
Transmissible spongiform encephalopathies are neurodegenerative diseases for which prions are the attributed pathogenic agents. A widely accepted theory assumes that prion replication is due to a direct interaction between the pathologic (PrP(Sc)) form and the host-encoded (PrP(C)) conformation, in a kind of autocatalytic process. Here we show that the overall features of the incubation time of prion diseases are readily obtained if the prion reaction is described by a simple mean-field model. An analytical expression for the incubation time distribution then follows by associating the rate constant to a stochastic variable log normally distributed. The incubation time distribution is then also shown to be log normal and fits the observed BSE (bovine spongiform encephalopathy) data very well. Computer simulation results also yield the correct BSE incubation time distribution at low PrP(C) densities.
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Affiliation(s)
- A S Ferreira
- Departamento de Física, Universidade Federal de Alagoas, 57072-970 Maceió (AL), Brazil
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Hirakauva EY, Ferraz MLG, Perez RM, Ferreira AS, Silva AE, Hauache O, Pestana JOM. Prevalence of diabetes mellitus in renal transplant patients with hepatitis B or C virus infection. Transplant Proc 2002; 34:3220-2. [PMID: 12493426 DOI: 10.1016/s0041-1345(02)03657-6] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Affiliation(s)
- E Y Hirakauva
- Escola Paulista de Medicina, Division of Gastroenterology, Universidade Federal de São Paulo, Brazil
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Cruz HJ, Ferreira AS, Freitas CM, Moreira JL, Carrondo MJ. Metabolic responses to different glucose and glutamine levels in baby hamster kidney cell culture. Appl Microbiol Biotechnol 1999; 51:579-85. [PMID: 10390815 DOI: 10.1007/s002530051435] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
Abstract
In this work, a BHK21 clone producing a recombinant antibody/cytokine fusion protein was used to study the dependence of cell metabolism on the glucose and glutamine levels in the culture medium. Results obtained indicate that both glucose and glutamine consumptions show a Michaelis-Menten dependence on glucose and glutamine concentrations respectively. A similar dependence is also observed for lactate and ammonia productions. The estimated value of the Michaelis constant for the dependence of lactate production on glucose (KLacGlc) was 1.4 +/- 0.1 mM and for the dependence of ammonia production on glutamine (KAmmGln) was 0.25 +/- 0.11 mM and 0.10 +/- 0.03 mM, at glucose concentrations of 0.28 mM and 5.6 mM respectively. At very low glucose concentrations, the glucose to lactate yield decreased markedly, showing a metabolic shift towards lower lactate production. This metabolic shift was also confirmed by the significant increase in the specific oxygen consumption rate also observed at low glucose concentrations. Although it was highly dependent on glucose concentration, the oxygen consumption also increased with the increase in glutamine concentration. At very low glutamine concentrations, the glutamine to ammonia yield increased, showing a more efficient glutamine metabolism.
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Affiliation(s)
- H J Cruz
- IBET/ITQB-Instituto de Biologia Experimental e Tecnológica/Instituto de Tecnologia Química e Biológica, Oeiras, Portugal
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Bittencourt PR, Antoniuk SA, Bigarella MM, da Costa JC, Doro MP, Ferreira AS, Fonseca LC, Gorz AM, Gonçalves e Silva GE, Marcourakis T. Carbamazepine and phenytoin in epilepsies refractory to barbiturates: efficacy, toxicity and mental function. Epilepsy Res 1993; 16:147-55. [PMID: 8269913 DOI: 10.1016/0920-1211(93)90029-7] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
A group of 51 patients with chronic cryptogenic or symptomatic localized epilepsy refractory to therapy with barbiturates underwent progressive substitution with phenytoin or carbamazepine, in standardized and randomized fashion. After drug changes were completed two thirds of the patients remained seizure free during a period of 6 months. A clearer effect of phenytoin and carbamazepine was seen on secondary generalized than on partial seizures. The frequency of severe side effects decreased after the change to phenytoin and carbamazepine. The group on carbamazepine improved in immediate and late recall, and in immediate and late recognition of pictures. The group on phenytoin improved significantly in the Stroop test. Patients changed to phenytoin, but not those changed to carbamazepine, became significantly more aggressive, anxious and depressive than when on phenobarbital, as measured by subjective scales. The results indicate that patients should not be considered refractory to antiepileptic drug therapy while on barbiturates. Cognitive dysfunction and mood changes observed in epilepsy may be temporary and dependent on the presence of seizures and/or on use of barbiturates.
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Affiliation(s)
- P R Bittencourt
- Unidade de Neurologia Clinica, Hospital Nossa Senhora das Graças, Curitiba, Brazil
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Rodrigues M, Dias O, Ferreira AS. [Arterial microcirculation of the human ovary. Preliminary report]. Bull Assoc Anat (Nancy) 1984; 68:59-63. [PMID: 6518303] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
Trying a standardization of methods for studying the microcirculation of the human ovary in reproductive period the authors studied 8 post-mortem ovaries of women aged between 18 and 35 years. It is concluded that the cleared method allows a better observation of the hilar and medullary vessels, while microangiography is better for the cortical vessels. The histological correlation is fundamental for the correct interpretation of the microangiographic images.
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