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1.
Physiol Behav ; 267: 114226, 2023 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-37150430

RESUMEN

The oxytocin family of neuropeptides is implicated in the regulation of sociality across vertebrates. Non-mammalian homologs of oxytocin, such as isotocin in fish and mesotocin in amphibians, reptiles and birds, all play crucial roles modulating social and reproductive behavior. In this study, we exogenously manipulated the mesotocinergic system in a highly social bird, the common waxbill Estrild astrild, and tested the effects on affiliative and aggressive behavior by performing tests of competition over food. Birds treated with mesotocin decreased almost all the behaviors we studied (movement, feeding, allopreening), while birds treated with an oxytocin antagonist showed a reduction only in social behaviors (aggressions and allopreening). We also found two sex-specific effects: mesotocin reduced allopreening more in males than females, and the oxytocin antagonist reduced aggressiveness only in females. Our results suggest sex-specific effects in the modulation of affiliative and aggressive behaviors via mesotocinergic pathways.


Asunto(s)
Oxitocina , Conducta Social , Animales , Masculino , Femenino , Oxitocina/farmacología , Oxitocina/metabolismo , Agresión , Peces , Aves
3.
Proc Biol Sci ; 289(1984): 20221677, 2022 10 12.
Artículo en Inglés | MEDLINE | ID: mdl-36476006

RESUMEN

Carotenoid-based colour signals can be costly to produce and maintain, and trade-offs between signalling and other fitness traits are expected. In mutually ornamented species, trade-offs with reproduction may be stronger for females than males, because females often dedicate more resources to offspring production, which may lead to plastic investment in colour signals and plastic sexual dichromatism. Oestradiol is a candidate mediator of this trade-off because it regulates reproductive physiology and may also influence the expression of coloration. We tested this hypothesis by giving female common waxbills (Estrilda astrild) either oestradiol (17ß-oestradiol) or empty implants during the early breeding season and measured spectral reflectance of carotenoid-based bill coloration weekly for two months. Using a model of avian vision, we found that bill colour in oestradiol-implanted females became less saturated, less red in hue and brighter, compared with control females and with unimplanted males. This resulted in a change in bill sexual dichromatism from imperceptible to perceptible. Results support the hypothesis that female reproductive physiology influences investment in coloration through changes in oestradiol and show a form of female-driven plastic sexual dichromatism. Greater sensitivity of female colour to physiological and/or environmental conditions helps explain why differences in sexual dichromatism among species differing in ecology often evolve owing to changes in female rather than male phenotype.


Asunto(s)
Ecología , Estradiol , Femenino , Masculino , Animales
5.
J. pediatr. (Rio J.) ; 98(4): 338-349, July-Aug. 2022. tab, graf
Artículo en Inglés | LILACS-Express | LILACS | ID: biblio-1386110

RESUMEN

Abstract Objective: The clinical cases of patients with multisystem inflammatory syndrome (MIS-C) were analyzed via a systematic review and meta-analysis of the clinical findings, treatments, and possible outcomes of articles retrieved via database searches. Sources: The authors searched the PubMed, Scielo, Web of Science, Science Direct, EMBASA, EBSCO, and Scopus databases for articles containing the keywords "multisystem inflammatory syndrome in children" or "MIS-C" or "PIMS-TS" or "SIMP" and "COVID-19" or "SARS-CoV-2" published between December 1st, 2019 and July 10th, 2021. Patient characteristics, tissue and organ comorbidities, the incidence of symptoms after COVID-19 infection, treatment, and patient evolution in the articles found were evaluated. The data were abstracted following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines and Newcastle-Ottawa Scale (NOS). Findings: In total, 98 articles (2275 patients) were selected for demographics, clinical treatment, and outcomes of patients diagnosed with MIS-C. The average age of children with MIS-C, 56.8% of whom were male, was of nine years. Fever (100%), gastrointestinal (GI) (82%), and abdominal pain (68%) were the decisive symptoms for the diagnosis of MIS-C. Shock and/or hypotension were common in patients with MIS-C. Cardiac symptoms (66%) predominated over respiratory (39%) and neurological (28%) symptoms. MIS-C treatment followed the common guidelines for treating children with septic shock and Kawasaki disease (KD) and proved to be effective. Conclusions: This meta-analysis highlights the main clinical symptoms used for the diagnosis of MIS-C, the differences between MIS-C and KD, and the severity of the inflammatory process and urgency for hospital care.

6.
J Exp Biol ; 225(6)2022 03 15.
Artículo en Inglés | MEDLINE | ID: mdl-35202471

RESUMEN

The dopaminergic (DAergic) system has well-known influences on behavioral and cognitive functions. Previous work with common waxbills (Estrilda astrild) reported context-specific DAergic effects that could have been due to social environment. Manipulating the dopamine D2-like receptor family (D2R) pathways had opposing effects on behavior depending on whether waxbills were tested alone or in a small cage with a mirror as a social stimulus. As waxbills are highly gregarious, it was hypothesized that being alone or perceiving that they have a companion might explain this context dependence. To test context-dependent DAergic effects, we compared behavioral effects of D2R manipulation in waxbills in the same familiar environment, but either alone or with a familiar, same-sex companion. We found that D2R agonism decreased movement and feeding, similar to previous results when testing waxbills alone. However, contrary to the hypothesis of dependence on social context, we found that the behavioral effects of the D2R agonist were unchanged when waxbills were tested with a companion. The context dependence reported earlier might thus be due to other factors, such as the stress of being in a novel environment (small cage) or with an unfamiliar social stimulus (mirror image). In tests with a companion, we also found a sex-specific social effect of D2R manipulation: D2R blocking tended to decrease aggression in males but to increase it in females. Together with past work, our results suggest that DAergic effects on behavior involve different types of context or sex dependence.


Asunto(s)
Aves , Dopamina , Agresión , Animales , Cognición , Dopamina/farmacología , Dopaminérgicos , Femenino , Masculino
7.
J Pediatr (Rio J) ; 98(4): 338-349, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-34863701

RESUMEN

OBJECTIVE: The clinical cases of patients with multisystem inflammatory syndrome (MIS-C) were analyzed via a systematic review and meta-analysis of the clinical findings, treatments, and possible outcomes of articles retrieved via database searches. SOURCES: The authors searched the PubMed, Scielo, Web of Science, Science Direct, EMBASA, EBSCO, and Scopus databases for articles containing the keywords "multisystem inflammatory syndrome in children" or "MIS-C" or "PIMS-TS" or "SIMP" and "COVID-19" or "SARS-CoV-2" published between December 1st, 2019 and July 10th, 2021. Patient characteristics, tissue and organ comorbidities, the incidence of symptoms after COVID-19 infection, treatment, and patient evolution in the articles found were evaluated. The data were abstracted following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines and Newcastle-Ottawa Scale (NOS). FINDINGS: In total, 98 articles (2275 patients) were selected for demographics, clinical treatment, and outcomes of patients diagnosed with MIS-C. The average age of children with MIS-C, 56.8% of whom were male, was of nine years. Fever (100%), gastrointestinal (GI) (82%), and abdominal pain (68%) were the decisive symptoms for the diagnosis of MIS-C. Shock and/or hypotension were common in patients with MIS-C. Cardiac symptoms (66%) predominated over respiratory (39%) and neurological (28%) symptoms. MIS-C treatment followed the common guidelines for treating children with septic shock and Kawasaki disease (KD) and proved to be effective. CONCLUSIONS: This meta-analysis highlights the main clinical symptoms used for the diagnosis of MIS-C, the differences between MIS-C and KD, and the severity of the inflammatory process and urgency for hospital care.


Asunto(s)
COVID-19 , COVID-19/complicaciones , COVID-19/terapia , Niño , Bases de Datos Factuales , Femenino , Humanos , Incidencia , Masculino , SARS-CoV-2 , Síndrome de Respuesta Inflamatoria Sistémica
8.
Front Vet Sci ; 8: 545708, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34485422

RESUMEN

Compared to rodents, sheep offer several attractive features as an experimental model for testing different medical and surgical interventions related to pathological gait caused by neurological diseases and injuries. To use sheep for development of novel treatment strategies in the field of neuroscience, it is key to establish the relevant kinematic features of locomotion in this species. To use sheep for development of novel treatment strategies in the field of neuroscience, it is crucial to understand fundamental baseline characteristics of locomotion in this species. Despite their relevance for medical research, little is known about the locomotion in the ovine model, and next to nothing about the three-dimensional (3D) kinematics of the hindlimb. This study is the first to perform and compare two-dimensional (2D) and 3D hindlimb kinematics of the sagittal motion during treadmill walking in the ovine model. Our results show that the most significant differences took place throughout the swing phase of the gait cycle were for the distal joints, ankle and metatarsophalangeal joint, whereas the hip and knee joints were much less affected. The results provide evidence of the inadequacy of a 2D approach to the computation of joint kinematics in clinically normal sheep during treadmill walking when the interest is centered on the hoof's joints. The findings from the present investigation are likely to be useful for an accurate, quantitative and objective assessment of functionally altered gait and its underlying neuronal mechanisms and biomechanical consequences.

9.
Biochim Biophys Acta Mol Basis Dis ; 1867(3): 166012, 2021 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-33212189

RESUMEN

Hypertension, one of the most common and severe comorbidities of obesity and overweight, is a worldwide epidemic affecting over 30% of the population. We induced overweight in young male rats (aged 58 days) by exposure to a hypercaloric high lipid (HL) diet in which 70% of the calories originated from fat. The HL diet also contained 33 or 57% higher Na+ than the control (CTR) diet. Over the following weeks the HL rats gradually became overweight (490 ± 12 g vs 427 ± 7 g in the CTR group after 15 weeks) with high visceral fat. They developed elevated systolic blood pressure (SBP) (141 ± 1.9 mmHg), which was fully restored to CTR values (128 ± 1.1 mmHg) by oral administration of Ang-(3-4) (Val-Tyr), the shortest renin-angiotensin-derived peptide. The overweight rats had lower plasma Na+ concentration that augmented to CTR values by Ang-(3-4) treatment. Na+ ingestion was depressed by 40% as result of the Ang-(3-4) treatment, whereas the urinary excretion of Na+ (UNaV) remained unmodified. The preservation of UNaV after Ang-(3-4) treatment - despite the sharp decrease in the dietary Na+ intake - can be ascribed to the normalization of renal type 1 angiotensin II receptors and Na+-transporting ATPases, both up-regulated in overweight rats. These renal effects complete a counterregulatory action on elevated renin-angiotensin activity that allows the high SBP to be normalized and body Na+ homeostasis to be restored concomitantly in overweight rats.


Asunto(s)
Angiotensinas/uso terapéutico , Presión Sanguínea/efectos de los fármacos , Ingestión de Energía/efectos de los fármacos , Hipertensión/tratamiento farmacológico , Sobrepeso/tratamiento farmacológico , Fragmentos de Péptidos/uso terapéutico , Animales , Hipertensión/complicaciones , Hipertensión/fisiopatología , Hipertensión/orina , Masculino , Sobrepeso/complicaciones , Sobrepeso/fisiopatología , Sobrepeso/orina , Ratas , Ratas Wistar , Sodio/metabolismo , Sodio/orina
10.
PLoS One ; 15(10): e0241485, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33125426

RESUMEN

BACKGROUND: The burden of treatment can overwhelm people living with type 2 diabetes and lead to poor treatment fidelity and outcomes. Chronic care programs must consider and mitigate the burden of treatment while supporting patients in achieving their goals. OBJECTIVE: To explore what patients with type 2 diabetes and their health providers consider are the workload and the resources they must mobilize, i.e., their capacity, to shoulder it. METHODS: We conducted focus groups comprised of 30 patients and 32 clinicians from three community health centers in Chile implementing the Chronic Care Model to reduce cardiovascular risk in patients with type 2 diabetes. Transcripts were analyzed using thematic content analysis techniques illuminated by the Minimally Disruptive Medicine framework. FINDINGS: Gaining access to and working with their clinicians, implementing complex medication regimens, and changing lifestyles burdened patients. To deal with the distress of the diagnosis, difficulties achieving disease control, and fear of complications, patients drew capacity from their family (mostly men), social environment (mostly women), lay expertise, and spirituality. Clinicians found that administrative tasks, limited formulary, and protocol rigidity hindered their ability to modify care plans to reduce patient workload and support their capacity. CONCLUSIONS: Chronic primary care programs burden patients living with type 2 diabetes while hindering clinicians' ability to reduce treatment workloads or support patient capacity. A collaborative approach toward Minimally Disruptive Medicine may result in treatments that fit the lives and loves of patients and improve outcomes.


Asunto(s)
Diabetes Mellitus Tipo 2/terapia , Adulto , Anciano , Chile/epidemiología , Costo de Enfermedad , Diabetes Mellitus Tipo 2/complicaciones , Diabetes Mellitus Tipo 2/epidemiología , Manejo de la Enfermedad , Femenino , Humanos , Estilo de Vida , Masculino , Persona de Mediana Edad , Médicos de Atención Primaria , Investigación Cualitativa
11.
Front Hum Neurosci ; 14: 6, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32116599

RESUMEN

Children with Down's syndrome (DS) might exhibit disrupted brain functional connectivity in the motor and prefrontal cortex. To inspect the alterations in brain activation and functional connectivity for children with DS, the functional near-infrared spectroscopy (fNIRS) method was applied to examine the brain activation difference in the motor and prefrontal cortex between the DS and typically developing (TD) groups during a fine motor task. In addition, small-world analysis based on graph theory was also carried out to characterize the topological organization of functional brain networks. Interestingly, behavior data demonstrated that the DS group showed significantly long reaction time and low accuracy as compared to the TD group (p < 0.05). More importantly, significantly reduced brain activations in the frontopolar area, the pre-motor, and the supplementary motor cortex (p < 0.05) were identified in the DS group compared with the TD group. Meanwhile, significantly high global efficiency (E g ) and short average path length (L p ) were also detected for the DS group. This pilot study illustrated that the disrupted connectivity of frontopolar area, pre-motor, and supplementary motor cortex might be one of the core mechanisms associated with motor and cognitive impairments for children with DS. Therefore, the combination of the fNIRS technique with functional network analysis may pave a new avenue for improving our understanding of the neural mechanisms of DS.

12.
J Exp Biol ; 223(Pt 3)2020 02 07.
Artículo en Inglés | MEDLINE | ID: mdl-31953366

RESUMEN

There is increasing interest in the genetic and physiological bases of behavioural differences among individuals, namely animal personality. One particular dopamine (DA) receptor gene (the dopamine receptor D4 gene) has been used as candidate gene to explain personality differences, but with mixed results. Here, we used an alternative approach, exogenously manipulating the dopaminergic system and testing for effects on personality assays in a social bird species, the common waxbill (Estrilda astrild). We treated birds with agonists and antagonists for DA receptors of both D1 and D2 receptor pathways (the latter includes the D4 receptor) and found that short-term manipulation of DA signalling had an immediate effect on personality-related behaviours. In an assay of social responses (mirror test), manipulation of D2 receptor pathways reduced time spent looking at the social stimulus (mirror image). Blocking D2 receptors reduced motor activity in this social assay, while treatment with a D2 receptor agonist augmented activity in this social assay but reduced activity in a non-social behavioural assay. Also, in the non-social assay, treatment with the D1 receptor antagonist markedly increased time spent at the feeder. These results show distinct and context-specific effects of the dopaminergic pathways on waxbill personality traits. Our results also suggest that experimental manipulation of DA signalling can disrupt a behavioural correlation (more active individuals being less attentive to mirror image) that is habitually observed as part of a behavioural syndrome in waxbills. We discuss our results in the context of animal personality, and the role of the DA system in reward and social behaviour.


Asunto(s)
Agonistas de Dopamina/farmacología , Antagonistas de Dopamina/farmacología , Dopamina/metabolismo , Personalidad , Pájaros Cantores/fisiología , Animales , Proteínas Aviares/genética , Proteínas Aviares/metabolismo , Femenino , Masculino , Receptores de Dopamina D1/genética , Receptores de Dopamina D1/metabolismo , Receptores de Dopamina D2/genética , Receptores de Dopamina D2/metabolismo
13.
Zootaxa ; 4576(3): zootaxa.4576.3.3, 2019 Apr 03.
Artículo en Inglés | MEDLINE | ID: mdl-31715748

RESUMEN

Cotithene gorayebi Valente, da Silva de Medeiros, sp. nov. is the first species of Cotithene Voss, 1940 described from the Amazonian forest in Brazil. The new species differs from other described species of Cotithene by its integument color pattern dissimilar between sexes and by the procoxal cavities separated by only a narrow septum in both male and female. It furthers differs by the unique morphology of male and female genitalia. A previously published key and phylogenetic matrix to Cotithene species were each modified to include the new species. The historical trajectory of host associations (inflorescences of Cyclanthaceae) in Cotithene is reanalyzed with the inclusion of the host of the new species. Previously known species are believed to be non-pollinators of various Cyclanthaceae; however, field observations of adults of the new species on inflorescences in anthesis of Evodianthus funifer (Cyclanthaceae) strongly suggest that this may be the first species of Cotithene known to play a role as a pollinator of Cyclanthaceae.


Asunto(s)
Escarabajos , Gorgojos , Animales , Brasil , Femenino , Bosques , Masculino , Filogenia
14.
Neurosci Biobehav Rev ; 98: 18-28, 2019 03.
Artículo en Inglés | MEDLINE | ID: mdl-30611796

RESUMEN

The recovery of walking function following spinal cord injury (SCI) is of major importance to patients and clinicians. In experimental SCI studies, a rat model is widely used to assess walking function, following thoracic spinal cord lesion. In an effort to provide a resource which investigators can refer to when seeking the most appropriate functional assay, the authors have compiled and categorized the behavioral assessments used to measure the deficits and recovery of the gait in thoracic SCI rats. These categories include kinematic and kinetic measurements. Within this categorization, we discuss the advantages and disadvantages of each type of measurement. The present review includes the type of outcome data that they produce, the technical difficulty and the time required to potentially train the animals to perform them, and the need for expensive or highly specialized equipment. The use of multiple kinematic and kinetic parameters is recommended to identify subtle deficits and processes involved in the compensatory mechanisms of walking function after experimental thoracic SCI in rats.


Asunto(s)
Análisis de la Marcha , Marcha/fisiología , Recuperación de la Función/fisiología , Traumatismos de la Médula Espinal/fisiopatología , Animales , Fenómenos Biomecánicos/fisiología , Modelos Animales de Enfermedad , Humanos
15.
Neurol Res ; 40(11): 963-971, 2018 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-30106355

RESUMEN

Functional recovery following general nerve reconstruction is often associated with poor results. Comparing to rat and mice experimental studies, there are much fewer investigations on nerve regeneration and repair in the sheep, and there are no studies on this subject using gait analysis in the sheep model as an assessment tool. Additionally, this is the first study evaluating obstacle negotiation and the compensatory strategies that take place at each joint in response to the obstacle during locomotion in the sheep model. This study aims to get kinematic data to serve as a template for an objective assessment of the ankle joint motion in future studies of common peroneal nerve (CP) injury and repair in the ovine model. Our results show that a moderately high obstacle set to 10% of the sheep's hindlimb length was associated to several spatial and temporal strategies in order to increase hoof height during obstacle negotiating. Sheep efficiently cleared an obstacle by increasing knee, ankle and metatarsophalangeal flexion during swing, whereas the hip joint is not affected. This study establishes the bounds of normal motion in the neurologically intact hindlimb when approached and cleared an obstacle and provides baseline data for further studies of peripheral nerve research in the ovine model.


Asunto(s)
Miembro Posterior , Locomoción , Ovinos , Animales , Fenómenos Biomecánicos , Femenino , Miembro Posterior/fisiología , Locomoción/fisiología , Ovinos/fisiología
16.
Lipids Health Dis ; 16(1): 245, 2017 Dec 16.
Artículo en Inglés | MEDLINE | ID: mdl-29246161

RESUMEN

BACKGROUND: Undernutrition during childhood leads to chronic diseases in adult life including hypertension, diabetes and chronic kidney disease. Here we explore the hypothesis that physiological alterations in the bioactive lipids pattern within kidney tissue might be involved in the progression of chronic kidney disease. METHODS: Membrane fractions from kidney homogenates of undernourished rats (RBD) were submitted to lipid extraction and analysis by thin layer chromatography and cholesterol determination. RESULTS: Kidneys from RBD rats had 25% lower cholesterol content, which disturb membrane microdomains, affecting Ca2+ homeostasis and the enzymes responsible for important lipid mediators such as phosphatidylinositol-4 kinase, sphingosine kinase, diacylglicerol kinase and phospholipase A2. We observed a decrease in phosphatidylinositol(4)-phosphate (8.8 ± 0.9 vs. 3.6 ± 0.7 pmol.mg-1.mim-1), and an increase in phosphatidic acid (2.2 ± 0.8 vs. 3.8 ± 1.3 pmol.mg-1.mim-1), being these lipid mediators involved in the regulation of key renal functions. Ceramide levels are augmented in kidney tissue from RBD rats (18.7 ± 1.4 vs. 21.7 ± 1.5 fmol.mg-1.min-1) indicating an ongoing renal lesion. CONCLUSION: Results point to an imbalance in the bioactive lipid generation with further consequences to key events related to kidney function, thus contributing to the establishment of chronic kidney disease.


Asunto(s)
Colesterol/metabolismo , Hipertensión/metabolismo , Riñón/metabolismo , Desnutrición/metabolismo , Fosfatos de Fosfatidilinositol/metabolismo , Insuficiencia Renal Crónica/metabolismo , 1-Fosfatidilinositol 4-Quinasa/genética , 1-Fosfatidilinositol 4-Quinasa/metabolismo , Animales , Animales Recién Nacidos , Ceramidas/metabolismo , Diacilglicerol Quinasa/genética , Diacilglicerol Quinasa/metabolismo , Regulación de la Expresión Génica , Hipertensión/etiología , Hipertensión/genética , Hipertensión/patología , Riñón/química , Metabolismo de los Lípidos , Masculino , Desnutrición/complicaciones , Desnutrición/genética , Desnutrición/patología , Microdominios de Membrana/química , Microdominios de Membrana/metabolismo , Ácidos Fosfatidicos/metabolismo , Fosfolipasas A2/genética , Fosfolipasas A2/metabolismo , Fosfotransferasas (Aceptor de Grupo Alcohol)/genética , Fosfotransferasas (Aceptor de Grupo Alcohol)/metabolismo , Ratas , Ratas Wistar , Insuficiencia Renal Crónica/etiología , Insuficiencia Renal Crónica/genética , Insuficiencia Renal Crónica/patología
17.
Bioinorg Chem Appl ; 2017: 2562780, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28814948

RESUMEN

The complexes cis-[Ru(quin)(dppm)2]PF6 and cis-[Ru(kynu)(dppm)2]PF6 (quin = quinaldate; kynu = kynurenate; dppm = bis(diphenylphosphino)methane) were prepared and characterized by elemental analysis, electronic, FTIR, 1H, and 31P{1H} NMR spectroscopies. Characterization data were consistent with a cis arrangement for the dppm ligands and a bidentate coordination through carboxylate oxygens of the quin and kynu anions. These complexes were not able to intercalate CT-DNA as shown by circular dichroism spectroscopy. On the other hand, bovine serum albumin (BSA) binding constants and thermodynamic parameters suggest spontaneous interactions with this protein by hydrogen bonds and van der Waals forces. Cytotoxicity assays were carried out on a panel of human cancer cell lines including HepG2, MCF-7, and MO59J and one normal cell line GM07492A. In general, the new ruthenium(II) complexes displayed a moderate to high cytotoxicity in all the assayed cell lines with IC50 ranging from 10.1 to 36 µM and were more cytotoxic than the precursor cis-[RuCl2(dppm)2]. The cis-[Ru(quin)(dppm)2]PF6 were two to three times more active than the reference metallodrug cisplatin in the MCF-7 and MO59J cell lines.

18.
Behav Brain Res ; 335: 132-135, 2017 09 29.
Artículo en Inglés | MEDLINE | ID: mdl-28803852

RESUMEN

Of all the detrimental effects of spinal cord injury (SCI), one of the most devastating is the disruption of the ability to perform functional movement. Very little is known on the recovery of hindlimb joint kinematics after clinically-relevant contusive thoracic lesion in experimental animal models. A new functional assessment instrument, the dynamic feet distance (DFD) was used to describe the distance between the two feet throughout the gait cycle in normal and affected rodents. The purpose of this investigation was the evaluation and characterization of the DFD during treadmill locomotion in normal and T9 contusion injured rats, using three-dimensional (3D) instrumented gait analysis. Despite that normal and injured rats showed a similar pattern in the fifth metatarsal head joints distance excursion, we found a significantly wider distance between the feet during the entire gait cycle following spinal injury. This is the first study to quantify the distance between the two feet, throughout the gait cycle, and the biomechanical adjustments made between limbs in laboratory rodents after nervous system injury.


Asunto(s)
Marcha/fisiología , Locomoción/fisiología , Traumatismos de la Médula Espinal/fisiopatología , Animales , Fenómenos Biomecánicos/fisiología , Prueba de Esfuerzo , Femenino , Pie/fisiopatología , Miembro Posterior/fisiopatología , Modelos Animales , Actividad Motora/fisiología , Ratas , Ratas Wistar , Recuperación de la Función/fisiología , Médula Espinal/patología
19.
An Acad Bras Cienc ; 88(4): 2441-2456, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27925032

RESUMEN

Over the years most studies on wake characteristics have been devoted to wind turbines, while few works are related to hydrokinetic turbines. Among studies applied to rivers, depth and width are important parameters for a suitable design. In this work, a numerical study of the wake in a horizontal-axis hydrokinetic turbine is performed, where the main objective is an investigation on the wake structure, which can be a constraining factor in rivers. The present paper uses the Reynolds Averaged Navier Stokes (RANS) flow simulation technique, in which the Shear-Stress Transport (SST) turbulent model is considered, in order to simulate a free hydrokinetic runner in a typical river flow. The NREL-PHASE VI wind turbine was used to validate the numerical approach. Simulations for a 3-bladed axial hydrokinetic turbine with 10 m diameter were carried out, depicting the expanded helical behavior of the wake. The axial velocity, in this case, is fully recovered at 12 diameters downstream in the wake. The results are compared with others available in the literature and also a study of the turbulence kinetic energy and mean axial velocity is presented so as to assess the influence of proximity of river surface from rotor in the wake geometry. Hence, even for a single turbine facility it is still necessary to consider the propagation of the wake over the spatial domain.

20.
Food Chem ; 203: 183-189, 2016 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-26948604

RESUMEN

This work reports an in-line electrochemical reagent generation coupled to a flow injection biamperometric procedure for the determination of SO3(2-). The method was based on a redox reaction between the I3(-) and SO3(2-) ions, after the diffusion of SO2 through a gas diffusion chamber. Under optimum experimental conditions, a linear response ranging from 1.0 to 12.0 mg L(-1) (R=0.9999 and n=7), a detection and quantification limit estimated at 0.26 and 0.86 mg L(-1), respectively, a standard deviation relative of 0.4% (n=10) for a reference solution of 4.0 mg L(-1) SO3(2-) and sampling throughput for 40 determinations per hour were achieved. Addition and recovery tests with juice and wine samples were performed resulting in a range between 92% and 110%. There were no significant differences at a 95% confidence level in the analysis of eight samples when comparing the new method with a reference procedure.


Asunto(s)
Bebidas/análisis , Técnicas Electroquímicas/métodos , Aditivos Alimentarios/análisis , Yoduros/química , Sulfitos/análisis , Bebidas/normas , Análisis de Inyección de Flujo/métodos , Jugos de Frutas y Vegetales/análisis , Jugos de Frutas y Vegetales/normas , Indicadores y Reactivos , Límite de Detección , Oxidación-Reducción , Estándares de Referencia , Soluciones , Vino/análisis , Vino/normas
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