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1.
Braz. j. biol ; 842024.
Artículo en Inglés | LILACS-Express | LILACS, VETINDEX | ID: biblio-1469252

RESUMEN

Abstract Several species of Cichla successfully colonized lakes and reservoirs of Brazil, since the 1960s, causing serious damage to local wildlife. In this study, 135 peacock bass were collected in a reservoir complex in order to identify if they represented a single dominant species or multiple ones, as several Cichla species have been reported in the basin. Specimens were identified by color pattern, morphometric and meristic data, and using mitochondrial markers COI, 16S rDNA and Control Region (CR). Overlapping morphological data and similar coloration patterns prevented their identification using the taxonomic keys to species identification available in the literature. However, Bayesian and maximum likelihood from sequencing data demonstrated the occurrence of a single species, Cichla kelberi. A single haplotype was observed for the 16S and CR, while three were detected for COI, with a dominant haplotype present in 98.5% of the samples. The extreme low diversity of the transplanted C. kelberi evidenced a limited number of founding maternal lineages. The success of this colonization seems to rely mainly on abiotic factors, such as increased water transparency of lentic environments that favor visual predators that along with the absence of predators, have made C. kelberi a successful invader of these reservoirs.


Resumo Muitas espécies de Cichla colonizaram com sucesso lagos e reservatórios do Brasil desde os anos 1960, causando graves prejuízos à vida selvagem nesses locais. Neste estudo, 135 tucunarés foram coletados em um complexo de reservatórios a fim de identificar se representavam uma espécie dominante ou múltiplas espécies, uma vez que diversas espécies de Cichla foram registradas na bacia. Os espécimes foram identificados com base na coloração, dados morfométricos e merísticos, e por marcadores mitocondriais COI, 16S rDNA e Região Controle (RC). A sobreposição dos dados morfométricos e o padrão similar de coloração impediram a identificação utilizando as chaves de identificação disponíveis na literatura. Entretanto, as análises bayesiana e de máxima verossimilhança de dados moleculares demonstraram a ocorrência de uma única espécie, Cichla kelberi. Um único haplótipo foi observado para o 16S e RC, enquanto três foram detectados para o COI, com um haplótipo dominante presente em 98,5% das amostras. A baixa diversidade nos exemplares introduzidos de C. kelberi evidenciou um número limitado de linhagens maternas fundadoras. O sucesso da invasão parece depender de fatores abióticos, como a maior transparência da água de ambientes lênticos que favorece predadores visuais que, atrelado à ausência de predadores, fez do C. kelberi um invasor bem-sucedido nesses reservatórios.

2.
Braz. j. biol ; 84: e248656, 2024. tab, graf
Artículo en Inglés | LILACS, VETINDEX | ID: biblio-1345542

RESUMEN

Abstract Several species of Cichla successfully colonized lakes and reservoirs of Brazil, since the 1960's, causing serious damage to local wildlife. In this study, 135 peacock bass were collected in a reservoir complex in order to identify if they represented a single dominant species or multiple ones, as several Cichla species have been reported in the basin. Specimens were identified by color pattern, morphometric and meristic data, and using mitochondrial markers COI, 16S rDNA and Control Region (CR). Overlapping morphological data and similar coloration patterns prevented their identification using the taxonomic keys to species identification available in the literature. However, Bayesian and maximum likelihood from sequencing data demonstrated the occurrence of a single species, Cichla kelberi. A single haplotype was observed for the 16S and CR, while three were detected for COI, with a dominant haplotype present in 98.5% of the samples. The extreme low diversity of the transplanted C. kelberi evidenced a limited number of founding maternal lineages. The success of this colonization seems to rely mainly on abiotic factors, such as increased water transparency of lentic environments that favor visual predators that along with the absence of predators, have made C. kelberi a successful invader of these reservoirs.


Resumo Muitas espécies de Cichla colonizaram com sucesso lagos e reservatórios do Brasil desde os anos 1960, causando graves prejuízos à vida selvagem nesses locais. Neste estudo, 135 tucunarés foram coletados em um complexo de reservatórios a fim de identificar se representavam uma espécie dominante ou múltiplas espécies, uma vez que diversas espécies de Cichla foram registradas na bacia. Os espécimes foram identificados com base na coloração, dados morfométricos e merísticos, e por marcadores mitocondriais COI, 16S rDNA e Região Controle (RC). A sobreposição dos dados morfométricos e o padrão similar de coloração impediram a identificação utilizando as chaves de identificação disponíveis na literatura. Entretanto, as análises bayesiana e de máxima verossimilhança de dados moleculares demonstraram a ocorrência de uma única espécie, Cichla kelberi. Um único haplótipo foi observado para o 16S e RC, enquanto três foram detectados para o COI, com um haplótipo dominante presente em 98,5% das amostras. A baixa diversidade nos exemplares introduzidos de C. kelberi evidenciou um número limitado de linhagens maternas fundadoras. O sucesso da invasão parece depender de fatores abióticos, como a maior transparência da água de ambientes lênticos que favorece predadores visuais que, atrelado à ausência de predadores, fez do C. kelberi um invasor bem-sucedido nesses reservatórios.


Asunto(s)
Animales , Cíclidos/genética , Filogenia , Variación Genética/genética , Haplotipos/genética , Lagos , Teorema de Bayes
3.
Int J Biol Macromol ; 202: 453-467, 2022 Mar 31.
Artículo en Inglés | MEDLINE | ID: mdl-35031317

RESUMEN

Electrohydrodynamic processing (EHDP) allows the use of a wide range of biopolymers and solvents, including food-grade biopolymers and green solvents, for the development of micro- and nanostructures. These structures present a high surface-area-to-volume ratio and different shapes and morphologies. The aim of this work was to design and produce hydroxypropyl methylcellulose (HPMC)-based micro- and nanostructures through EHD processing using green solvents, while exploring the influence of process and solution parameters, and incorporating a bioactive extracted from a food by-product. Low (LMW) and high (HMW) molecular weight HPMC have been used as polymers. The design-of-experiments methodology was used to determine the effects of process parameters (polymer concentration, flow rate, tip-to-collector distance, and voltage) of EHDP on the particle and fibre diameter, aspect ratio, diameter distribution, aspect ratio distribution, and percentage of fibre breakage. Additionally, melanoidins extracted from spent coffee grounds were encapsulated into the HPCM-based structures at a concentration of 2.5 mg melanoidins/mL of the polymer solution. Polymer solutions were characterised regarding their viscosity, surface tension and conductivity, and showed that the incorporation of melanoidins increased the viscosity and conductivity values of the polymer solutions. The developed structures were characterised regarding their thermal properties, crystallinity and morphology before and after melanoidin incorporation and it was observed that melanoidin incorporation did not significantly influence the characteristics of the produced micro- and nanostructures. Based on the results, it is possible to envision the use of the produced micro- and nanostructures in a wide range of applications, both in food and biomedical fields.


Asunto(s)
Nanoestructuras , Polímeros , Conductividad Eléctrica , Derivados de la Hipromelosa , Polímeros/química
4.
Braz J Biol ; 84: e248656, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34730686

RESUMEN

Several species of Cichla successfully colonized lakes and reservoirs of Brazil, since the 1960's, causing serious damage to local wildlife. In this study, 135 peacock bass were collected in a reservoir complex in order to identify if they represented a single dominant species or multiple ones, as several Cichla species have been reported in the basin. Specimens were identified by color pattern, morphometric and meristic data, and using mitochondrial markers COI, 16S rDNA and Control Region (CR). Overlapping morphological data and similar coloration patterns prevented their identification using the taxonomic keys to species identification available in the literature. However, Bayesian and maximum likelihood from sequencing data demonstrated the occurrence of a single species, Cichla kelberi. A single haplotype was observed for the 16S and CR, while three were detected for COI, with a dominant haplotype present in 98.5% of the samples. The extreme low diversity of the transplanted C. kelberi evidenced a limited number of founding maternal lineages. The success of this colonization seems to rely mainly on abiotic factors, such as increased water transparency of lentic environments that favor visual predators that along with the absence of predators, have made C. kelberi a successful invader of these reservoirs.


Asunto(s)
Cíclidos , Animales , Teorema de Bayes , Cíclidos/genética , Variación Genética/genética , Haplotipos/genética , Lagos , Filogenia
5.
J Intellect Disabil Res ; 65(12): 1058-1072, 2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-34713518

RESUMEN

BACKGROUND: Cardiorespiratory fitness (CRF) prompts antiatherogenic adaptations in vascular function and structure. However, there is an extraordinary interindividual variability in response to a standard dose of exercise, wherein a substantial number of adults with intellectual and developmental disabilities (IDD) do not improve CRF. We (1) evaluated the effects of 12-month of moderate-intensity continuous training (MICT) on CRF and arterial stiffness and (2) tested whether an additional 3-month of high-intensity interval training (HIIT) would add to improvements in CRF responsiveness and arterial stiffness. METHODS: Fifteen adults with mild-to-moderate IDD (male adults = 9, 30.1 ± 7.5 years old) met 3 days per week for 30 min MICT for 12 months, after which the incidence of CRF responsiveness was calculated (≥5.0% change in absolute peak VO2 ). Thereafter, responders and non-responders started HIIT for 3 months with identical daily training load/frequency. Peak VO2 , local and regional indices of arterial stiffness were assessed prior to and after each period. RESULTS: Sixty per cent of the participants were non-responders following MICT, but the incidence dropped to 20% following HIIT (P = 0.03). Absolute peak VO2 values reached significant difference from pre-intervention (+0.38 ± 0.08 L min-1 , P = 0.001) only when HIIT was added. Lower limb pulse wave velocity (PWV) decreased following MICT (-0.8 ± 1.1 m s-1 , P = 0.049), whereas central PWV only decreased following HIIT (-0.8 ± 0.9 m s-1 , P = 0.013). CONCLUSIONS: Cardiorespiratory fitness responsiveness and reductions in PWV to a 12-month MICT period in adults with IDD improved following a period of HIIT programme inducing higher metabolic stress.


Asunto(s)
Capacidad Cardiovascular , Entrenamiento de Intervalos de Alta Intensidad , Rigidez Vascular , Adulto , Niño , Discapacidades del Desarrollo , Humanos , Masculino , Análisis de la Onda del Pulso , Adulto Joven
6.
Nurse Educ Today ; 97: 104722, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-33341062

RESUMEN

BACKGROUND: Auscultation of heart and lung sounds is a foundational competency for Registered Nurses (RNs). Precise and timely assessments are important for the early detection and recognition of the deteriorating patient. Studies have shown that improved teaching methods that incorporate emerging technologies and address different learning styles are needed to improve competency in auscultation. METHOD: Undergraduate nursing students (n = 127) were randomized into treatment and control groups. The control group received the usual preparation in auscultation learning strategies. The treatment group received the usual training plus three auscultation learning sessions that were each 2 h in length (cardiac, pulmonary and mixed sounds). RESULTS: The virtual auscultation teaching strategy had a significant impact on undergraduate nursing student's competency in recognizing heart murmurs. The treatment group also had increased scores compared to the control group increased scores in distinguishing normal versus abnormal heart and lung sounds, identification of crackles and diminished breath sounds. CONCLUSION: Virtual auscultation as a teaching strategy was shown to have a positive impact on undergraduate student nurse competence in accurately identifying heart and lung sounds.


Asunto(s)
Bachillerato en Enfermería , Estudiantes de Enfermería , Auscultación , Competencia Clínica , Humanos , Aprendizaje
7.
Annu Int Conf IEEE Eng Med Biol Soc ; 2020: 1840-1843, 2020 07.
Artículo en Inglés | MEDLINE | ID: mdl-33018358

RESUMEN

Chronic wound assessment and wound healing are important for diagnostic, follow up and wound treatment. However, this growing disease affecting nearly 2 thousand million and 5.7 million people in the USA and Europe, costing around $20 billion and $8 thousand million USD per year, still relies on subjective human assessment of wounds. A scoping review allowed us to identify 109 articles that map the literature on the topic of computer vision for chronic wound assessment and healing. These results were carefully analyzed and mapped into relevant clinical challenges associated with this field, identifying the maturity of each different computer vision challenge that needs addressing. Results show that wound size and tissue type classification already have interesting work, but various other clinical areas are in need of larger datasets and computer vision research efforts for achieving a relevant impact in today's clinical routine.


Asunto(s)
Computadores , Cicatrización de Heridas , Administración Tópica , Europa (Continente) , Humanos , Examen Físico
8.
Annu Int Conf IEEE Eng Med Biol Soc ; 2020: 6032-6035, 2020 07.
Artículo en Inglés | MEDLINE | ID: mdl-33019346

RESUMEN

The teaching process of auscultation is complex in itself, and difficult to operate since it requires a wide spectrum of patients with the most diverse cardiopulmonary pathologies, readily available during teaching and assessment hours, for an ever-growing number of medical students. In this paper we will focus on how virtual patient technologies can promote the evolution of the current teaching methodologies, promoting better learning. The chosen methodology was: a) a review of available medical simulation technologies for auscultation teaching; b) a case study illustrating how a virtual patient simulation technology has been successfully used to teach and certify auscultation skills. Results show the positive impact and high acceptability of virtual patient simulation technologies in the teaching of auscultation to medical students.


Asunto(s)
Simulación de Paciente , Estudiantes de Medicina , Auscultación , Humanos , Tecnología
9.
Carbohydr Polym ; 213: 217-227, 2019 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-30879663

RESUMEN

Soluble flaxseed gum (SFG) extracted at different temperatures (25, 40, and 60 °C) was analyzed in relation to the yield, polysaccharides and phenolics composition, surface charge, color, and rheological properties. The yield of SFG extract increased as the extraction temperature increased. The SFG xylan was the main component regardless the extraction temperature, but a reduction of substituents on the xylose chain was observed when increasing the extraction temperature. The phenolic compounds were also affected by the extraction temperature, influencing the antioxidant capacity of the gum. For all the extraction temperatures, SFG aqueous solutions showed a shear time-independent and shear-thinning behavior. Furthermore, oscillatory measurements showed a prevailing viscous character, but the decrease of the extraction temperature resulted in an increase of both G' and G". Therefore, SFG extracted at low extraction temperatures showed higher viscous and elastic properties, while high extraction temperatures increased the antioxidant activity.


Asunto(s)
Antioxidantes/farmacología , Compuestos de Bifenilo/antagonistas & inhibidores , Fenoles/farmacología , Picratos/antagonistas & inhibidores , Gomas de Plantas/química , Temperatura , Xilanos/farmacología , Antioxidantes/química , Antioxidantes/aislamiento & purificación , Fenoles/química , Fenoles/aislamiento & purificación , Gomas de Plantas/aislamiento & purificación , Reología , Xilanos/química , Xilanos/aislamiento & purificación
10.
Poult Sci ; 98(2): 1037-1046, 2019 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-30165698

RESUMEN

The red-legged partridge (Alectoris rufa) is a feathered game species of great socioeconomic importance in its native range and also in the UK. The aim of this study was to present a detailed comparison of meat's lipid fraction obtained from wild and farm-raised specimens and simultaneously compare the breast and leg meat portions. Meat from wild specimens had a significant (P < 0.05) lower proportion of saturated fatty acid (less 5.1%) and presented better P/S and n-6/n-3 ratios, and atherogenicity index than farm-raised counterparts. The wild specimens presented significant (P < 0.001) higher contents of total vitamin E (8.8 vs. 2.2 µg/g of fresh meat), is for that reason less prone to lipid peroxidation than farm-raised specimens. Meat portions differed significantly (P < 0.05) on total lipid and total cholesterol contents and in all partial sums of fatty acids. The breast was leaner (0.86 vs. 1.47 g/100 g of meat), with lower total cholesterol (37.5 vs. 54.7 mg/100 g of meat), lower saturated fatty acid, monounsaturated fatty acid, polyunsaturated fatty acid, and n-6 polyunsaturated fatty acid (less 0.27, 0.28, 0.10, and 0.11 g/100 g of fresh meat, correspondingly). Regarding the fatty acid ratios and lipid quality indexes, breast meat presents better n-6/n-3 ratio and atherogenicity and thrombogenicity indexes.


Asunto(s)
Galliformes , Lípidos/análisis , Carne/análisis , Músculo Esquelético/fisiología , Valor Nutritivo , Crianza de Animales Domésticos , Animales , Animales Salvajes , Músculos Pectorales/fisiología , Portugal
11.
Poult Sci ; 97(12): 4330-4341, 2018 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-30101299

RESUMEN

It is now well established that exogenous ß-1,4-xylanases improve the nutritive value of wheat-based diets for poultry. Among other factors, the mechanism of action of exogenous enzymes may involve a microbial route resulting from the generation of prebiotic xylo-oligosaccharides (XOS) in the birds' gastro-intestinal (GI) tract. In a series of three experiments, the effect of XOS on the performance of broilers fed wheat or corn-based diets was investigated. In experiment 1, birds receiving diets supplemented with XOS displayed an increased weight gain (P = 0.08). The capacity of XOS to improve the performance of animals during a longer trial (42 d) was investigated (Experiment 2). The data revealed that diet supplementation with XOS, tested at two incorporation rates (0.1 and 1 g/kg), or with an exogenous ß-1,4-xylanase resulted in an increased nutritive value of the wheat-based diet. An improvement in animal performance was accompanied by a shift in the microbial populations colonizing the upper portions of the GI tract. XOS were also able to improve the performance of broilers fed a corn-based diet, although the effects were not apparent at incorporation rates of 10 g/kg. Together these studies suggest that in some cases the capacity of ß-1,4-xylanases to improve the nutritive value of wheat-based diets is more related to their ability to produce prebiotic XOS than to their ability to degrade arabinoxylans. The extremely low quantities of XOS used in this study also challenge the depiction of a prebiotic being a quantitatively fermented substrate. These data also bring into question the validity of the "cell wall" mechanism, as XOS elicited an effect with clearly no action on endosperm cell wall integrity and yet the performance effects noted were equivalent or superior to the added enzymes.


Asunto(s)
Alimentación Animal/análisis , Pollos/metabolismo , Dieta/veterinaria , Glucuronatos/farmacología , Oligosacáridos/farmacología , Prebióticos , Animales , Pollos/crecimiento & desarrollo , Masculino , Distribución Aleatoria , Triticum , Zea mays
12.
Annu Int Conf IEEE Eng Med Biol Soc ; 2017: 2610-2613, 2017 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-29060434

RESUMEN

There are several electronic stethoscopes available on the market today, with a very high potential for healthcare namely telemedicine, assisted decision and education. However, there are no recent comparatives studies published about the recording quality of auscultation sounds. In this study we aim to: a) define a ranking, according to experts opinion of 6 of the most relevant electronic stethoscopes on the market today; b) verify if there are any relations between a stethoscope's performance and the type of pathology present; c) analyze if some pathologies are more easily identified than others when using electronic auscultation. Our methodology consisted in creating two study groups: the first group included 18 cardiologists and cardiology house officers, acting as the gold standard of this work. The second included 30 medical students. Using a database of heart sounds recorded in real hospital environments, we applied questionnaires to observers from each group. The first group listened to 60 cardiac auscultations recorded by the 6 stethoscopes, and each one was asked to identify the pathological sound present: aortic stenosis, mitral regurgitation or normal. The second group was asked to choose, between two auscultation recordings, using as criteria the best sound quality for the identification of pathological sounds. Results include a total of 1080 evaluations, in which 72% of cases were correctly diagnosed. A detailed breakdown of these results is presented in this paper. As conclusions, results showed that the impact of the differences between stethoscopes is very small, given that we did not find statistically significant differences between all pairs of stethoscopes. Normal sounds showed to be easier to identify than pathological sounds, but we did not find differences between stethoscopes in this identification.


Asunto(s)
Auscultación Cardíaca , Ruidos Cardíacos , Estetoscopios
13.
Annu Int Conf IEEE Eng Med Biol Soc ; 2016: 3019-3022, 2016 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-28268948

RESUMEN

Auscultation is currently both a powerful screening tool, providing a cheap and quick initial assessment of a patient's clinical condition, and a hard skill to master. The teaching of auscultation in Universities is today reduced to an unsuitable number of hours. Virtual patient simulators can potentially mitigate this problem, by providing an interesting high-quality alternative to teaching with real patients or patient simulators. In this paper we evaluate the pedagogical impact of using a virtual patient simulation technology in a short workshop format for medical students, training them to detect cardiac pathologies. Results showed a significant improvement (+16%) in the differentiation between normal and pathological cases, although longer duration formats seem to be needed to accurately identify specific pathologies.


Asunto(s)
Auscultación/métodos , Simulación de Paciente , Tecnología/educación , Tecnología/métodos , Interfaz Usuario-Computador , Adolescente , Adulto , Anciano , Enfermedades Cardiovasculares/diagnóstico , Niño , Preescolar , Competencia Clínica , Simulación por Computador , Humanos , Persona de Mediana Edad , Proyectos Piloto , Enseñanza , Adulto Joven
14.
Annu Int Conf IEEE Eng Med Biol Soc ; 2016: 5384-5387, 2016 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-28269476

RESUMEN

Heart auscultation is one of the basic exams performed during a patient physical examination, but it is also one that has a high skill ceiling. Decision support systems can provide physicians with a tool that can help to reduce the demanding skill requirements of this exam. Nevertheless, this second opinion needs to be delivered in a timely interval in order to be truly useful for a physician. To do this we need not only optimized algorithms, but also a well designed system. In this paper, we have studied how two different data exchange protocols, that define how data should be transferred from an acquisition to a process module, can impact the celerity of delivering second opinion to a physician. With data collected from real exams, acquired in a field hospital initiative in Brazil, we recreated two use cases that allowed us to measure performance in the form of time and resources spent, as well as power consumption. Results have shown that different data exchange protocols can have a significant impact on a decision support system response time.


Asunto(s)
Sistemas de Apoyo a Decisiones Clínicas , Ruidos Cardíacos/fisiología , Algoritmos , Brasil , Sistemas Especialistas , Humanos , Derivación y Consulta , Procesamiento de Señales Asistido por Computador , Programas Informáticos
15.
Annu Int Conf IEEE Eng Med Biol Soc ; 2016: 5608-5611, 2016 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-28269526

RESUMEN

The gastroenterology specialty could benefit from the introduction of Computer Assisted Decision (CAD) systems, since gastric cancer is a serious concern in which an accurate and early diagnosis usually leads to a good prognosis. Still, the way doctors interact with these systems is very important because it will often determine its embracement or rejection, as any gains in productivity will frequently hinge on how comfortable they are with it. Using other types of interaction paradigms such as voice and motion control, is important in a way that typical inputs such as keyboard and mouse are sometimes not the best choice for certain clinical scenarios. In order to ascertain how a doctor could control a hypothetical CAD system during a gastroenterology exam, we measured the natural response of users when faced with three different task requests, using three types of interaction paradigms: voice, gesture and endoscope. Results fit in what was expected, with gesture control being the most intuitive to use, and the endoscope being on the other edge. All the technologies are mature enough to cope with the response concepts the participants gave us. However, when having into account the scenario context, better natural response scores may not always be the best choice for implementation. That way, simplification or reduction of tasks, along with a well tought-out interface, or even mixing more oriented paradigms for particular requests, could allow for better system control with fewer inconveniences for the user.


Asunto(s)
Sistemas de Computación , Endoscopía Gastrointestinal/instrumentación , Neoplasias Gástricas/diagnóstico , Estudiantes de Medicina , Interfaz Usuario-Computador , Diagnóstico Precoz , Gastroenterología , Gestos , Humanos , Voz
16.
Ann Biomed Eng ; 42(10): 2132-42, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-25103604

RESUMEN

Recently we showed that fluid accumulation in the neck can narrow the upper airway (UA) and increase its collapsibility, which may exacerbate obstructive sleep apnea (OSA). However, the available methods for measuring neck fluid volume (NFV) are inconvenient and expensive. Narrowing of the UA due to fluid accumulation could change acoustic characteristics of respiratory sounds. In this study, we developed a novel approach for non-invasive estimation of NFV from acoustic measurements. Twenty-eight healthy subjects lay awake and supine for 90 min while NFV and tracheal sounds were measured simultaneously using bioimpedance and a microphone, respectively. Sets of tracheal sound features were calculated in time and frequency domains and were reduced using methods based on regression and minimum-redundancy-maximum-relevance. The resulting feature sets were applied to a multi-linear regression and a mixture-density neural network to estimate NFV. Our results show very small relative estimation errors of 1.25 and 3.23%, based on the regression and neural network methods, respectively. These results support the practical application of this technology in diagnosing fluid accumulation in the neck and its possible contributions to the pathogenesis of OSA.


Asunto(s)
Líquidos Corporales/fisiología , Transferencias de Fluidos Corporales/fisiología , Cuello/fisiología , Acústica , Adulto , Impedancia Eléctrica , Femenino , Humanos , Modelos Lineales , Masculino , Persona de Mediana Edad , Redes Neurales de la Computación , Ruidos Respiratorios , Posición Supina
17.
Artículo en Inglés | MEDLINE | ID: mdl-24110252

RESUMEN

Stress is a major factor for the degradation of cardiac health in first responder professionals such as firefighters. Monitoring stress during real events might be the key for controlling this problem. In this paper we inspect how standard heart rate variability (HRV) measures are associated with the self-perception of stress of firefighters in action, supported by an advanced technological solution to acquire this data. Results obtained from more than 94 hours of annotated ECG recordings of firefighters in action are promising, showing positive association with various standard HRV measures. Given the richness of the gathered data, we have also measured the association of the HRV measures with the stage of a firefighting event (pre, during, post), obtaining some interesting results that hint that the psychological impact of the post-event may be one of the most concerning situations for a firefighter, motivating further studies on this in the future.


Asunto(s)
Bomberos/psicología , Frecuencia Cardíaca/fisiología , Autoimagen , Estrés Psicológico/fisiopatología , Estrés Psicológico/psicología , Adulto , Teléfono Celular , Humanos , Masculino , Factores de Tiempo
18.
Acta Biomater ; 9(11): 9086-97, 2013 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-23816652

RESUMEN

Ulvan, extracted from the green algae Ulva lactuca, and chitosan, extracted from Loligo forbesis squid-pen, were carboxymethylated, yielding polysaccharides with an average degree of substitution of ∼98% (carboxymethyl ulvan, CMU) and ∼87% (carboxymethyl chitosan, N,O-CMC). The carboxymethylation was confirmed by Fourier transform infrared spectroscopy and quantified by conductimetric titration and 1H nuclear magnetic resonance. The average molecular weight increased with the carboxymethylation (chitosan, Mn 145→296 kDa and Mw 227→416 kDa; ulvan, Mn 139→261 kDa and Mw 368→640 kDa), indicating successful chemical modifications. Mixtures of the modified polysaccharides were tested in the formulation of polyacrylic acid-free glass-ionomer bone cements. Mechanical and in vitro bioactivity tests indicate that the inclusion of CMU in the cement formulation, i.e. 0.50:0.50 N,O-CMC:CMU, enhances its mechanical performance (compressive strength 52.4±8.0 MPa and modulus 2.3±0.3 GPa), generates non-cytotoxic cements and induces the diffusion of Ca and/or P-based moieties from the surface to the bulk of the cements.


Asunto(s)
Cementos para Huesos/farmacología , Quitosano/análogos & derivados , Polímeros/farmacología , Polisacáridos/farmacología , Acetilación/efectos de los fármacos , Animales , Materiales Biocompatibles/química , Materiales Biocompatibles/farmacología , Cementos para Huesos/química , Calcio/análisis , Muerte Celular/efectos de los fármacos , Quitosano/química , Quitosano/farmacología , Fuerza Compresiva/efectos de los fármacos , Módulo de Elasticidad/efectos de los fármacos , Cementos de Ionómero Vítreo/química , Espectroscopía de Resonancia Magnética , Ensayo de Materiales , Ratones , Microscopía Electrónica de Rastreo , Peso Molecular , Fósforo/análisis , Polímeros/química , Polisacáridos/química , Porosidad , Espectrometría por Rayos X , Espectroscopía Infrarroja por Transformada de Fourier , Agua/química , Difracción de Rayos X
19.
J Control Release ; 163(3): 361-7, 2012 Nov 10.
Artículo en Inglés | MEDLINE | ID: mdl-23041274

RESUMEN

In the current study, core-crosslinked polymeric micelles (DEX-PMs) loaded with three different DEX derivatives designed to display different drug release kinetics, were evaluated for cancer therapy and compared to another effective nanomedicine formulation (long-circulating liposomes encapsulating dexamethasone, LCL-DEX). Pharmacokinetic studies with both radiolabeled dexamethasone and polymer showed that these polymeric systems have long circulating half-lives and may accumulate at the tumor site to a higher extent than liposomes. The in vitro drug release profiles and circulating drug levels in the blood stream show that DEX-PMs with dexamethasone covalently entrapped via a sulfone ester-containing linker (DMSL2) have prolonged circulation time and intermediate drug release kinetics compared to the other polymeric DEX-releasing systems. Furthermore, as the free dexamethasone circulating levels were similar when administered as DMSL2-PM or LCL-DEX, these systems were evaluated simultaneously for antitumor efficacy in B16F10 melanoma bearing mice. The corticosteroid-targeted systems inhibited tumor growth to a similar extent and both increased survival compared to free drug. Recently antitumor efficacy of targeted formulations has been correlated with a systemic effect: a decrease of white blood cell count. In this study all three polymeric systems, liposomes as well as free drug had similar effects on the number of circulating white blood cells, although white blood cell counts recovered faster in the group receiving free drug. In conclusion, corticosteroid-targeting with a polymeric system or a liposomal system translates in similar therapeutic effects. The proven high versatility of the PM with possible optimization and adjustment of the drug release to that required by the therapeutic application, clearly demonstrates the potential of these systems for the treatment of chronic inflammatory diseases including cancer.


Asunto(s)
Antineoplásicos/administración & dosificación , Dexametasona/administración & dosificación , Melanoma Experimental/tratamiento farmacológico , Neoplasias Cutáneas/tratamiento farmacológico , Animales , Antineoplásicos/química , Antineoplásicos/farmacocinética , Dexametasona/química , Dexametasona/farmacocinética , Liposomas , Masculino , Melanoma Experimental/metabolismo , Melanoma Experimental/patología , Ratones , Ratones Endogámicos C57BL , Micelas , Polímeros/administración & dosificación , Polímeros/química , Neoplasias Cutáneas/metabolismo , Neoplasias Cutáneas/patología , Distribución Tisular , Carga Tumoral/efectos de los fármacos
20.
Braz J Biol ; 72(3): 583-5, 2012 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-22990830

RESUMEN

Thirty-two specimens of Columbina picui (picui ground-dove) were examined, and a collection of arthropods was made by washing the external surface of the body and the nasal cavity. The species in the order Phthiraptera found and their respective prevalences, mean abundance and mean intensity were: Columbicola passerinae (84.4%; 10.3; 12.2), Hohorstiella passerinae (21.9%; 0.7; 3.1) and Physconelloides eurysema (3.1%; 0.1; 2). The gamasid mites found in the birds and their respective prevalences, mean abundance and mean intensity were: Pellonyssus marui (31.3%; 1.2; 3.9), Ornithonyssus bursa (15.6%; 0.2. ;1.2) and Mesonyssus sp. (6.3%; 0.1; 1). Columbicola passerinae, H. passerinae, P. eurysema, O. bursa, P. marui and Mesonyssus sp. were recorded for the first time infecting C. picui in Brazil. Except for O. bursa, the other species are reported for the first time in the state of Rio Grande do Sul, Brazil.


Asunto(s)
Enfermedades de las Aves/parasitología , Columbidae/parasitología , Infestaciones Ectoparasitarias/veterinaria , Ácaros/fisiología , Phthiraptera/fisiología , Animales , Enfermedades de las Aves/epidemiología , Brasil/epidemiología , Columbidae/clasificación , Infestaciones Ectoparasitarias/epidemiología , Infestaciones Ectoparasitarias/parasitología , Interacciones Huésped-Parásitos , Prevalencia
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