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1.
Eur J Appl Physiol ; 124(2): 607-622, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37684396

RESUMO

PURPOSE: Running at a given speed can be achieved by taking large steps at a low frequency or on the contrary by taking small steps at a high frequency. The consequences of a change in step frequency, at a fixed speed, affects the stiffness of the lower limb differently. In this study, we compared the running mechanics and kinematics at different imposed step frequencies (from 2 step s-1 to 3.6 step s-1) to understand the relationship between kinematic and kinetic parameters. METHODS: Eight recreational male runners ran on a treadmill at 5 different speeds and 5 different step frequencies. The lower-limb segment motion and the ground reaction forces were recorded. Mechanical powers, general gait parameters, lower-limb movements and coordination were investigated. RESULTS: At low step frequencies, in order to limit the magnitude of the ground reaction force, the vertical stiffness is reduced and thus runners deviate from an elastic rebound. At high step frequencies, the stiffness is increased and the elastic rebound is optimised in its ability to absorb and restore energy during the contact phase. CONCLUSION: We studied the consequences of a change in step frequency on the bouncing mechanics of running. We showed that the lower limb stiffness and the intersegmental coordination of the lower-limb segments are affected by running step frequency rather than speed. The runner rather adapts their lower limb stiffness to match a step frequency for a given speed than the opposite.


Assuntos
Marcha , Extremidade Inferior , Humanos , Masculino , Fenômenos Biomecânicos , Movimento , Movimento (Física)
2.
J Physiol ; 601(8): 1467-1482, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36852473

RESUMO

The response of spinal motoneurons to synaptic input greatly depends on the activation of persistent inward currents (PICs), which in turn are enhanced by the neuromodulators serotonin and noradrenaline. Local vibration (LV) induces excitatory Ia input onto motoneurons and may alter neuromodulatory inputs. Therefore, we investigated whether LV influences the contribution of PICs to motoneuron firing. This was assessed in voluntary contractions with concurrent, ongoing LV, as well as after a bout of prolonged LV. High-density surface electromyograms (HD-EMG) of the tibialis anterior were recorded with a 64-electrode matrix. Twenty males performed isometric, triangular, dorsiflexion contractions to 20% and 50% of maximal torque at baseline, during LV of the tibialis anterior muscle, and after 30-min of LV. HD-EMG signals were decomposed, and motor units tracked across time points to estimate PICs through a paired motor unit analysis, which quantifies motor unit recruitment-derecruitment hysteresis (ΔF). During ongoing LV, ΔF was lower for both 20% and 50% ramps. Although significant changes in ΔF were not observed after prolonged LV, a differential effect across the motoneuron pool was observed. This study demonstrates that PICs can be non-pharmacologically modulated by LV. Given that LV leads to reflexive motor unit activation, it is postulated that lower PIC contribution to motoneuron firing during ongoing LV results from decreased neuromodulatory inputs associated with lower descending corticospinal drive. A differential effect in motoneurons of different recruitment thresholds after prolonged LV is provocative, challenging the interpretation of previous observations and motivating future investigations. KEY POINTS: Neuromodulatory inputs from the brainstem influence motoneuron intrinsic excitability through activation of persistent inward currents (PICs). PICs make motoneurons more responsive to excitatory input. We demonstrate that vibration applied on the muscle modulates the contribution of PICs to motoneuron firing, as observed through analysis of the firing of single motor units. The effects of PICs on motoneuron firing were lower when vibration was concurrently applied during voluntary ramp contractions, likely due to lower levels of neuromodulation. Additionally, prolonged exposure to vibration led to differential effects of lower- vs. higher-threshold motor units on PICs, with lower-threshold motor units tending to present an increased and higher-threshold motor units a decreased contribution of PICs to motoneuron firing. These results demonstrate that muscle vibration has the potential to influence the effects of neuromodulation on motoneuron firing. The potential of using vibration as a non-pharmacological neuromodulatory intervention should be further investigated.


Assuntos
Neurônios Motores , Vibração , Masculino , Humanos , Neurônios Motores/fisiologia , Músculo Esquelético/fisiologia , Eletromiografia , Contração Isométrica
3.
J Exp Biol ; 224(22)2021 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-34676869

RESUMO

As the largest extant legged animals, elephants arguably face the most extreme challenge for stable standing. In this study, we investigated the displacement of the centre of pressure of 12 elephants during quiet standing. We found that the average amplitude of the oscillations in the lateral and fore-aft directions was less than 1.5 cm. Such amplitudes for postural oscillation are comparable with those of dogs and other species, suggesting that some aspects of sensorimotor postural control do not scale with size.


Assuntos
Elefantes , Animais , Cães , Equilíbrio Postural , Postura
4.
Crit Care ; 25(1): 381, 2021 11 08.
Artigo em Inglês | MEDLINE | ID: mdl-34749792

RESUMO

BACKGROUND: COVID-19 is primarily a respiratory disease; however, there is also evidence that it causes endothelial damage in the microvasculature of several organs. The aim of the present study is to characterize in vivo the microvascular reactivity in peripheral skeletal muscle of severe COVID-19 patients. METHODS: This is a prospective observational study carried out in Spain, Mexico and Brazil. Healthy subjects and severe COVID-19 patients admitted to the intermediate respiratory (IRCU) and intensive care units (ICU) due to hypoxemia were studied. Local tissue/blood oxygen saturation (StO2) and local hemoglobin concentration (THC) were non-invasively measured on the forearm by near-infrared spectroscopy (NIRS). A vascular occlusion test (VOT), a three-minute induced ischemia, was performed in order to obtain dynamic StO2 parameters: deoxygenation rate (DeO2), reoxygenation rate (ReO2), and hyperemic response (HAUC). In COVID-19 patients, the severity of ARDS was evaluated by the ratio between peripheral arterial oxygen saturation (SpO2) and the fraction of inspired oxygen (FiO2) (SF ratio). RESULTS: Healthy controls (32) and COVID-19 patients (73) were studied. Baseline StO2 and THC did not differ between the two groups. Dynamic VOT-derived parameters were significantly impaired in COVID-19 patients showing lower metabolic rate (DeO2) and diminished endothelial reactivity. At enrollment, most COVID-19 patients were receiving invasive mechanical ventilation (MV) (53%) or high-flow nasal cannula support (32%). Patients on MV were also receiving sedative agents (100%) and vasopressors (29%). Baseline StO2 and DeO2 negatively correlated with SF ratio, while ReO2 showed a positive correlation with SF ratio. There were significant differences in baseline StO2 and ReO2 among the different ARDS groups according to SF ratio, but not among different respiratory support therapies. CONCLUSION: Patients with severe COVID-19 show systemic microcirculatory alterations suggestive of endothelial dysfunction, and these alterations are associated with the severity of ARDS. Further evaluation is needed to determine whether these observations have prognostic implications. These results represent interim findings of the ongoing HEMOCOVID-19 trial. Trial registration ClinicalTrials.gov NCT04689477 . Retrospectively registered 30 December 2020.


Assuntos
COVID-19/fisiopatologia , Unidades de Terapia Intensiva/tendências , Microvasos/fisiopatologia , Unidades de Cuidados Respiratórios/tendências , Síndrome do Desconforto Respiratório/fisiopatologia , Índice de Gravidade de Doença , Adulto , Idoso , Brasil/epidemiologia , COVID-19/diagnóstico , COVID-19/epidemiologia , Feminino , Humanos , Masculino , México/epidemiologia , Microcirculação/fisiologia , Pessoa de Meia-Idade , Músculo Esquelético/irrigação sanguínea , Músculo Esquelético/fisiopatologia , Estudos Prospectivos , Síndrome do Desconforto Respiratório/diagnóstico , Síndrome do Desconforto Respiratório/epidemiologia , Espanha/epidemiologia
5.
Eur J Appl Physiol ; 120(1): 91-106, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31701272

RESUMO

PURPOSE: Walking against a constant horizontal traction force which either hinders or aids the motion of the centre of mass of the body (COM) will create a discrepancy between the positive and negative work being done by the muscles and may thus affect the mechanics and energetics of walking. We aimed at investigating how this imbalance affects the exchange between potential and kinetic energy of the COM and how its dynamics is related to specific spatiotemporal organisation of motor pool activity in the spinal cord. To understand if and how the spinal cord activation may be associated with COM dynamics, we also compared the neuromechanical adjustments brought on by a horizontal force with published data about those brought on by a slope. METHODS: Ten subjects walked on a treadmill at different speeds with different traction forces. We recorded kinetics, kinematics, and electromyographic activity of 16 lower-limb muscles and assessed the spinal locomotor output by mapping them onto the rostrocaudal location of the motoneuron pools. RESULTS: When walking with a hindering force, the major part of the exchange between potential and kinetic energy of the COM occurs during the first part of stance, whereas with an aiding force exchanges increase during the second part of stance. Those changes occur since limb and trunk orientations remain aligned with the average orientation of the ground reaction force vector. Our results also show the sacral motor pools decreased their activity with an aiding force and increased with a hindering one, whereas the lumbar motor pools increased their engagement both with an aiding and a hindering force. CONCLUSION: Our findings suggest that applying a constant horizontal force results in similar modifications of COM dynamics and spinal motor output to those observed when walking on slopes, consistent with common principles of motor pool functioning and biomechanics of locomotion.


Assuntos
Músculo Esquelético/fisiologia , Medula Espinal/fisiologia , Caminhada/fisiologia , Adulto , Fenômenos Biomecânicos , Pesos e Medidas Corporais , Humanos , Masculino , Músculo Esquelético/inervação , Distribuição Aleatória , Propriedades de Superfície
6.
Eur J Appl Physiol ; 120(7): 1575-1589, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32394064

RESUMO

PURPOSE: Much like running on a slope, running against/with a horizontal traction force which either hinders/aids the forward motion of the runner creates a shift in the positive and negative muscular work, which in turn modifies the bouncing mechanism of running. The purpose of the study is to (1) investigate the energy changes of the centre of mass and the storage/release of energy throughout the step during running associated with speed and increasing hindering and aiding traction forces; and (2) compare these changes to those observed when running on a slope. METHODS: Ground reaction forces were measured on eight subjects running on an instrumented treadmill against different traction forces at different speeds. RESULTS: As compared to unperturbed running, running against/with a traction force increases/decreases positive external work by ~ 20-70% and decreases/increases negative work by ~ 40-60%, depending on speed and traction force. The external power to maintain forward motion against a traction is contained by increasing the pushing time and step frequency. When running with an aiding force, the external power during the brake is limited by increasing braking time. Furthermore, the aerial time is increased to reduce the power required to reset the limbs each step. CONCLUSION: Our results show that the bouncing mechanism of running against/with a hindering/aiding traction force is equivalent to that of running on a positive/negative slope.


Assuntos
Fenômenos Biomecânicos/fisiologia , Músculo Esquelético/fisiologia , Corrida , Tração , Adulto , Teste de Esforço , Humanos , Masculino , Movimento (Física) , Adulto Jovem
7.
Med Oral Patol Oral Cir Bucal ; 25(4): e468-e473, 2020 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-32388528

RESUMO

BACKGROUND: This study compared three different concentrations of EO (1.25%, 2.5% and 5%) for the treatment of oral vascular anomalies (OVAs). MATERIAL AND METHODS: This was a retrospective comparative analysis of patients with OVAs treated with EO. Anomalies smaller than 20 mm were included. The patients were treated with 1.25% (G1), 2.5% (G2), and 5% (G3) and clinical data were obtained. The number of sessions, the final volume and dose of EO were statistically analyzed to verify effectiveness and safety of the treatment. The different concentrations of EO were compared considering the number of sessions, the final volume and total dose of EO. Analysis of covariance (ANCOVA) was used to evaluate the influence of covariates on the outcomes. A p-value < 0.05 was considered significant. RESULTS: Nineteen women and 11 men with a median age of 54 years were included. The OVAs were most frequent in the lip (n=14) and cheek (n=9). All lesions exhibited complete clinical healing within 28 days. Patients of G3 required fewer sessions than those of G2 (p=0.017), a lower final volume compared to the other groups (p<0.001), and a lower total dose than G1 (p<0.001). Patients of G1 used a lower total dose than G2 (p=0.003). CONCLUSIONS: The concentration of 5% EO performed better than 1.25% and 2.5% for sclerotherapy of OVAs measuring up to 20 mm. This preliminary result should be the preferred concentration of EO to provide an effective and safe treatment of OVAs.


Assuntos
Soluções Esclerosantes/uso terapêutico , Escleroterapia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Ácidos Oleicos , Estudos Retrospectivos , Resultado do Tratamento
8.
Oral Dis ; 23(4): 471-476, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28028908

RESUMO

BACKGROUND: The amalgam-associated oral lichenoid lesion (AAOLL) shows clinical and histopathological features similar to oral lichen planus (OLP). Molecular researches to improve knowledge of pathogenesis and clinical behavior of AAOLL are still scarce. OBJECTIVE: We investigated for the first time the use of loss of heterozygosity (LOH) as a molecular approach for genetic characterization of AAOLL in comparison with OLP and evaluated the cell proliferation index. MATERIALS AND METHODS: The sample comprised nine AAOLLs, 10 OLPs, and eight NOMs matched by patients' gender and age. LOH was assessed using polymorphic microsatellite markers at chromosomes 9p (D9S157, D9S162, D9S171), 11q (D11S1369), and 17p (TP53, AFM238WF2). Cell proliferation was assessed by immunohistochemical expression of Ki-67 (MIB-1). The association between LOH and Ki-67 was investigated. RESULTS: Loss of heterozygosity occurred in 5/9 AAOLLs and in 2/10 OLPs in at least one marker each, while NOM showed no LOH. Cell proliferation index in AAOLL ranged from 2 to 23%. There was no association between cell proliferation and LOH, independent of the marker. CONCLUSION: Our study shows that the profile of molecular changes in AAOLL and OLP, evaluated by LOH and Ki-67 expression, is similar. Additional studies including larger samples should be performed to confirm or to refute our findings.


Assuntos
Amálgama Dentário/efeitos adversos , Erupções Liquenoides/etiologia , Perda de Heterozigosidade , Doenças da Boca/etiologia , Mucosa Bucal/fisiopatologia , Adulto , Idoso , Estudos de Casos e Controles , Proliferação de Células , Feminino , Humanos , Imuno-Histoquímica , Antígeno Ki-67/metabolismo , Líquen Plano Bucal/genética , Líquen Plano Bucal/fisiopatologia , Erupções Liquenoides/genética , Erupções Liquenoides/fisiopatologia , Masculino , Repetições de Microssatélites , Pessoa de Meia-Idade , Doenças da Boca/genética , Doenças da Boca/fisiopatologia , Polimorfismo Genético
9.
DNA Repair (Amst) ; 129: 103532, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37453244

RESUMO

Organisms have evolved a complex system, called the DNA damage response (DDR), which maintains genome integrity. The DDR is responsible for identifying and repairing a variety of lesions and alterations in DNA. DDR proteins coordinate DNA damage detection, cell cycle arrest, and repair, with many of these events regulated by protein phosphorylation. In the human proteome, 23 proteins contain the BRCT (BRCA1 C-Terminus domain) domain, a modular signaling domain that can bind phosphopeptides and mediate protein-protein interactions. BRCTs can be found as functional single units, tandem (tBRCT), triplet (tpBRCT), and quartet. Here we examine the evolution of the tpBRCT architecture present in TOPBP1 (DNA topoisomerase II binding protein 1) and ECT2 (epithelial cell transforming 2), and their respective interaction partners RAD9 (Cell cycle checkpoint control protein RAD9) and CYK-4 (Rac GTPase-activating protein 1), with a focus on the conservation of the phosphopeptide-binding residues. The pair TOPBP1-RAD9 arose with the Eukaryotes and ECT2-CYK-4 with the Eumetazoans. Triplet structural and functional characteristics were conserved in almost all organisms. The first unit of the triplet (BRCT0) is different from the other two BRCTs but conserved between orthologs for both TOPBP1 and ECT2. BRCT domain evolution simulations suggest a trend to retain the singlet or towards two or three BRCT copies per protein consistent with functional tBRCT and tpBRCT architectures. Our results shed light on the emergence of the function and architecture of multiple BRCT domain organizations and provide information about the evolution of the BRCT triplet. Knowledge of BRCT domain evolution can improve the understanding of DNA damage response mechanisms and signal transduction in DDR.


Assuntos
Proteína BRCA1 , Proteínas de Ciclo Celular , Humanos , Proteína BRCA1/metabolismo , Domínios Proteicos , Proteínas de Ciclo Celular/metabolismo , Dano ao DNA , Transdução de Sinais , Fosforilação , Ligação Proteica
10.
Braz J Med Biol Res ; 55: e12036, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35976269

RESUMO

The study of functional reorganization following stroke has been steadily growing supported by advances in neuroimaging techniques, such as functional magnetic resonance imaging (fMRI). Concomitantly, graph theory has been increasingly employed in neuroscience to model the brain's functional connectivity (FC) and to investigate it in a variety of contexts. The aims of this study were: 1) to investigate the reorganization of network topology in the ipsilesional (IL) and contralesional (CL) hemispheres of stroke patients with (motor stroke group) and without (control stroke group) motor impairment, and 2) to predict motor recovery through the relationship between local topological variations of the functional network and increased motor function. We modeled the brain's FC as a graph using fMRI data, and we characterized its interactions with the following graph metrics: degree, clustering coefficient, characteristic path length, and betweenness centrality (BC). For both patient groups, BC yielded the largest variations between the two analyzed time points, especially in the motor stroke group. This group presented significant correlations (P<0.05) between average BC changes and the improvements in upper-extremity Fugl-Meyer (UE-FM) scores at the primary sensorimotor cortex and the supplementary motor area for the CL hemisphere. These regions participate in processes related to the selection, planning, and execution of movement. Generally, higher increases in average BC over these areas were related to larger improvements in UE-FM assessment. Although the sample was small, these results suggest the possibility of using BC as an indication of brain plasticity mechanisms following stroke.


Assuntos
Córtex Motor , Reabilitação do Acidente Vascular Cerebral , Acidente Vascular Cerebral , Humanos , Imageamento por Ressonância Magnética/métodos , Córtex Motor/diagnóstico por imagem , Córtex Motor/patologia , Recuperação de Função Fisiológica , Acidente Vascular Cerebral/diagnóstico por imagem , Extremidade Superior
11.
Eur Arch Paediatr Dent ; 23(4): 537-546, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35838891

RESUMO

BACKGROUND: This systematic review and meta-analysis aimed to answer the following question: Are children and adolescents with attention deficit hyperactivity disorder (ADHD) more likely to have gingival or periodontal disease-related outcomes than their non-ADHD peers? METHODS: Searches were conducted in the following databases: Embase, Scopus, Web of Science, and PubMed. Google Scholar and OpenGrey were also verified. Observational studies were included in which children and adolescents with ADHD were compared with their healthy peers in terms of gingival and/or periodontal endpoints. Bias appraisal was performed using the Joann Briggs tool for case-control and cross-sectional studies. Meta-analysis was performed using R language. Results are reported as mean difference (MD) and odds ratio (OR). Statistical analyses were performed in RStudio. RESULTS: A total of 149 records were identified in the searches. Seven studies were included. The meta-analysis showed that children and adolescents with ADHD had a higher mean gingival bleeding index (percentage) than their non-ADHD peers (MD = 11.25; CI = 0.08-22.41; I2 = 73%). There was no difference between groups for plaque index (MD = 4.87; CI = - 2.56 to 12.30; I2 = 63%) and gingivitis (OR = 1.42; CI = 0.22-9.21; I2 = 76%). Regarding the assessment of risk of bias, the major issue found in the articles was the absence of analyses for the control of confounding factors. CONCLUSION: Children and adolescents with ADHD had more gingival bleeding than their non-ADHD peers, but no difference regarding plaque or gingivitis was detected between groups. CLINICAL REGISTRATION: CRD42021258404.


Assuntos
Transtorno do Deficit de Atenção com Hiperatividade , Placa Dentária , Gengivite , Adolescente , Transtorno do Deficit de Atenção com Hiperatividade/complicações , Criança , Humanos
12.
Rev Chilena Infectol ; 39(3): 265-272, 2022 06.
Artigo em Espanhol | MEDLINE | ID: mdl-36156688

RESUMO

BACKGROUND: Ocular toxoplasmosis (OT) is a retinochoroiditis that evolves with several episodes of inflammation and can occur both in the congenital or acquired form of the disease, Aim: To describe the frequency and clinical characteristics of OT in infants aged 0 to 12 months, children of mothers with positive serology for toxoplasmosis in the perinatal period. METHODS: Cross-sectional descriptive, ambispective study. RESULTS: Infants from 0 to 12 months of age, whose mothers had positive serology for toxoplasmosis in the perinatal period, referred to the pediatric ophthalmology service for evaluation, were admitted. Demographic variables, maternal and infant serology and the results of the ophthalmological examination were collected. Data were analyzed in SPSS v21 Results: 46.4% of 125 infants had OT, of them 67.2% were female, (p = 0.04) the median age was 6 months, 41% had IgG and IgM positive. The lesions were bilateral in 82.8%, central in 86.2%, and inactive in 81%. Retinochoroiditis was accompanied by strabismus in 41%. CONCLUSIONS: The frequency of OT in this population of infants with congenital toxoplasmosis was high. more than 80% of the eye lesions were inactive, centrally located and bilaterally involved.


Assuntos
Toxoplasmose Congênita , Toxoplasmose Ocular , Anticorpos Antiprotozoários , Criança , Estudos Transversais , Feminino , Humanos , Imunoglobulina G , Imunoglobulina M , Lactente , Masculino , Gravidez , Toxoplasmose Congênita/diagnóstico , Toxoplasmose Congênita/epidemiologia , Toxoplasmose Ocular/complicações , Toxoplasmose Ocular/diagnóstico , Toxoplasmose Ocular/epidemiologia
13.
J Stomatol Oral Maxillofac Surg ; 121(6): 704-712, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32574868

RESUMO

AIM: The aim of this systematic review and meta-analysis was to compare the occurrence of tissue artifacts in punch and scalpel biopsies of oral and maxillofacial lesions. METHODS: Electronic searches were conducted in four databases (PubMed, Scopus, Web of Science and Ovid). Study selection, data extraction, and quality assessment of the included articles were performed independently by two authors. An evaluation of the strength of the evidence (GRADE) and meta-analysis were conducted. Odds ratio and confidence intervals (CI) were provided. RESULTS: After the removal of duplicates, 466 references were identified. Four studies evaluating artifacts, such as crush, fragmentation, splits, hemorrhage, curling, and orientation artifacts and also those induced by improper surgical removal, were included. Specimens obtained using scalpel biopsy were 2.98 times more likely (CI=1.53-5.80) to present crushes and 12.36 times more likely (CI=2.64-57.83) to present splits than specimens procured using punch biopsy. Scalpel biopsies were also 2.40 times more likely to present fragmentation than punch biopsies (CI=1.01-5.72). No significant differences between scalpel and punch biopsies were found concerning the presence of hemorrhage, curling, or orientation artifacts and those induced by improper surgical removal. After sensitivity analysis, samples obtained from scalpel biopsy were 6.18 times more likely to present hemorrhage than those from a punch biopsy (CI=2.21-17.28). Based on the GRADE evaluation, the confidence in the effect estimate of the sub-group analysis of crush and fragmentation was moderate. For the other subgroup analysis, the confidence was low or very low. CONCLUSION: Punch biopsies were less likely to produce artifacts, such as crush, fragmentation, splits, and hemorrhage, than biopsies obtained with a scalpel.


Assuntos
Doenças da Boca , Artefatos , Biópsia , Humanos , Doenças da Boca/diagnóstico , Doenças da Boca/patologia
14.
Phys Med Biol ; 54(2): 175-85, 2009 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-19088392

RESUMO

The existence of a coupling between changes in neuronal activity, cerebral blood flow and blood oxygenation is well known. The explicit relationship between these systems, however, is complex and remains a subject of intense research. Here, we use direct electrophysiological recordings to predict blood flow and oxygenation changes measured with optical methods during parametric stimulation applied to the somatosensory cortex in rat brain. Using a multimodal model of the cerebral functional unit, we estimate a neuro-vascular and a neuro-metabolic transfer function relating the experimentally measured neural responses with the inputs to a vascular model predicting hemodynamic and blood oxygenation changes. We show that our model can accurately predict experimentally measured parametric hemodynamic evoked responses by using a single linear transfer function relationship with a reduced number of state parameters to relate the level of neural activity to evoked cerebral blood flow and oxygen metabolism changes. At the same time, we characterize the metabolic and vascular neural response functions and interpret their physiological significance.


Assuntos
Córtex Somatossensorial/irrigação sanguínea , Córtex Somatossensorial/fisiologia , Animais , Fenômenos Biofísicos , Circulação Cerebrovascular , Fenômenos Eletrofisiológicos , Masculino , Modelos Neurológicos , Oxigênio/sangue , Ratos , Ratos Sprague-Dawley
15.
Int J Oral Maxillofac Surg ; 48(5): 635-643, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30459066

RESUMO

The aim of this study was to describe 40 cases of acquired oral syphilis (AOS) and to discuss the distribution of demographic characteristics, clinical features, and differential diagnosis of the disease. A retrospective study was conducted covering a 17-year period at a single institution in southern Brazil. Moreover, a literature review was performed through a search of the PubMed database for articles on AOS published between 1955 and March 2018. Data were analyzed descriptively. The predominant group within the case series was male patients in their twenties. The vast majority of cases (92.5%) were in the secondary stage of the disease. The lips were the most commonly affected site, with greyish-white mucous patches and reddish ulcers. In the literature review, the largest number of reported cases came from North America. Male patients in the third and fourth decades of life were most affected. AOS occurred more commonly as mucous patches and ulcers on the tongue and palate. Similarities regarding the distribution by sex, age, and anatomical location were found in the present study when compared to cases reported elsewhere. Clinicians, oral pathologists, and maxillofacial surgeons should familiarize themselves with the variable spectrum of signs and symptoms of AOS in their clinical practice to improve diagnosis and management.


Assuntos
Doenças da Boca , Sífilis , Doenças da Língua , Brasil , Humanos , Masculino , Estudos Retrospectivos
16.
J Appl Physiol (1985) ; 126(3): 607-615, 2019 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-30496707

RESUMO

A high proportion of patients with chronic obstructive pulmonary disease (COPD) experience problems during the performance of activities of daily living (ADLs). We aimed to determine the effects of a comprehensive 8-wk pulmonary rehabilitation program on the physiologic response to and performance of ADLs in patients with COPD. Before and after pulmonary rehabilitation, 31 patients with COPD [71% men; mean age: 64.2 (SD 8.4) years; mean forced expiratory volume in the first second: 54.6 (SD 19.9) % predicted] performed physical function tests, the Canadian Occupational Performance Measure (COPM), and an ADL test consisting of the following: putting on socks, shoes, and vest; stair climbing; washing up four dishes, cups, and saucers; doing groceries and putting away groceries in a cupboard; folding eight towels; and vacuum cleaning for 4 min. Metabolic load, ventilation, and dynamic hyperinflation were assessed using an Oxycon mobile device. In addition, symptoms of dyspnea and fatigue and time to complete ADLs were recorded. After rehabilitation, patients with COPD used a significantly lower proportion of their peak aerobic capacity and ventilation to perform ADLs, accompanied by lower Borg scores for dyspnea and fatigue. Furthermore, patients needed significantly less time to complete ADLs. Dynamic hyperinflation occurred during the performance of ADLs, which did not change following pulmonary rehabilitation. Changes in physical function, including six-min walk distance, constant work rate test, quadriceps muscle strength, and COPM were significantly correlated with change in average total oxygen uptake during the performance of the ADL test. A comprehensive pulmonary rehabilitation program can improve the physiologic response to and actual performance of ADLs in patients with COPD. NEW & NOTEWORTHY A high proportion of patients with chronic obstructive pulmonary disease (COPD) experience problems during the performance of activities of daily living (ADLs). This study clearly demonstrated that a comprehensive pulmonary rehabilitation program can improve the performance of ADLs in patients with COPD, indicated by a significantly shorter time to perform ADLs and a lower metabolic load and dyspnea sensation.


Assuntos
Pulmão/fisiopatologia , Doença Pulmonar Obstrutiva Crônica/fisiopatologia , Atividades Cotidianas , Dispneia/fisiopatologia , Teste de Esforço/métodos , Tolerância ao Exercício/fisiologia , Fadiga/fisiopatologia , Feminino , Volume Expiratório Forçado/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade , Consumo de Oxigênio/fisiologia , Testes de Função Respiratória/métodos
17.
Oral Dis ; 14(6): 510-3, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18826382

RESUMO

AIM: To investigate the immunoexpression and diagnostic applicability of human erythrocyte-type glucose transporter protein (GLUT-1) in oral peripheral nerve sheath tumors. MATERIAL AND METHODS: Specimens diagnosed as oral peripheral nerve sheath tumors archived in the Oral Pathology Service of Universidade Federal de Minas Gerais from 1966 to 2006 were evaluated. Thirty-four lesions were included: 15 traumatic neuromas, 11 neurofibromas, four neurilemmomas, and four malignant peripheral nerve sheath tumors (MPNST). One case of neurofibroma was associated with neurofibromatosis type I. Immunohistochemistry for S-100 and GLUT-1 was performed. S-100 was immunopositive in all lesions. RESULTS: Benign lesions were immunopositive for GLUT-1 except in two (18.2%) cases of neurofibromas. In the traumatic neuroma, the perineuriums were immunopositive for GLUT-1. In the neurofibroma, the immunoreactivity was heterogeneous. Immunopositivity was observed at levels of 54.5% in the periphery of the lesion, 9.1% in the center, and 18.2% in both. The neurilemmoma demonstrated immunopositivity in the capsule. One case (25%) of MPNST presented GLUT-1 positive stain in occasional cells distributed homogeneously in all the tumor area. CONCLUSION: GLUT-1 is a useful marker for perineurial cells and should be included in the oral peripheral nerve sheath tumors immunophenotyping thus aiding in the correct diagnosis of these lesions.


Assuntos
Transportador de Glucose Tipo 1/análise , Neoplasias Bucais/patologia , Neoplasias de Bainha Neural/patologia , Biomarcadores Tumorais/análise , Núcleo Celular/patologia , Tecido Conjuntivo/patologia , Diagnóstico Diferencial , Humanos , Imuno-Histoquímica , Imunofenotipagem , Fibras Nervosas/patologia , Neurilemoma/patologia , Neurofibroma/patologia , Neurofibromatose 1/patologia , Neuroma/patologia , Proteínas S100/análise
18.
Minerva Stomatol ; 57(9): 453-7, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18923380

RESUMO

Mucoepidermoid carcinomas (MECs) are the most common malignancy of the salivary glands demonstrating a wide range of histologic variants and behavior. However, the sclerosing mucoepidermoid carcinoma (SMEC), a morphologic variant of this tumor is extremely rare and has been described almost exclusively in the major glands. The prominent sclerosis observed may obscure its typical morphological feature resulting in a diagnostic challenge. We describe herein a case of SMEC in a 43-year-old-woman, occurring in the minor salivary glands of palate. To our knowledge only 13 cases have been reported until this moment, being only 2 in minor salivary glands. We also performed the immunohistochemical evaluation of c-erbB-2 and Ki-67, searching for an association with the histopathological findings and behavior.


Assuntos
Carcinoma Mucoepidermoide/patologia , Neoplasias das Glândulas Salivares/patologia , Glândulas Salivares Menores , Adulto , Feminino , Humanos , Imuno-Histoquímica
19.
Minerva Stomatol ; 57(1-2): 59-63, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18427372

RESUMO

Inflammatory myofibroblastic tumor is a rare lesion composed of myofibroblastic spindle cells accompanied by inflammatory infiltrate. The objective of this paper is to report an uncommon case of inflammatory myofibroblastic tumor located in the alveolar mucosa of the mandible. A 33-year-old male presented an asymptomatic tumoral lesion, firm, pedunculated, pink-colored, covered by smooth mucosa, with focal ulceration, measuring 30x20x20 mm, located in the left posterior alveolar mucosa. Clinical diagnosis was soft tissue tumor. An excisional biopsy was made. Microscopic examination showed compact fascicular spindle cells proliferation with a diffuse inflammatory infiltrate of plasma cells, lymphocytes, and eosinophils. Large ganglion-like cells were observed. The lesional cells were immunopos-itive to vimentin, a-smooth muscle actin, muscle specific actin, and CD68. Negative immunostain was observed to S-100, Bcl-2, Ki-67, desmin, CD34, and cytokeratin. A diagnosis of inflammatory myofibroblastic tumor was performed. After 28 months of follow-up there was no recurrence. Although no evidence of oral inflammatory myofibroblastic tumor recurrence or malignant transformation has been reported, it has been observed that in inflammatory myofibroblastic tumor of other regions a prolonged follow-up is necessary after surgical excision.


Assuntos
Mucosa Bucal , Neoplasias Bucais/patologia , Neoplasias de Tecido Muscular/patologia , Adulto , Humanos , Masculino , Mandíbula
20.
Physiotherapy ; 104(4): 408-416, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30477678

RESUMO

OBJECTIVES: To compare the effects of two similar 6-month protocols of high-intensity exercise training, in water and on land, in patients with chronic obstructive pulmonary disease (COPD). DESIGN: Randomised controlled trial. SETTING: University-based outpatient clinic. PARTICIPANTS: Thirty-six patients with predominantly moderate-to-severe COPD completed the study. INTERVENTION: Patients were evaluated at baseline, at 3 months and at the end of the programme (i.e. 6 months). For both groups, the 6-month protocol consisted of high-intensity endurance and strength exercises with gradual increase in time and/or workload, totalling 60 sessions. MAIN OUTCOMES: Objective monitoring of physical activity in daily life (PADL, primary outcome), lung function, peripheral and respiratory muscle strength, body composition, maximal and submaximal exercise capacity, functional status, quality of life, and symptoms of anxiety and depression. RESULTS: After 6 months of training, a significant improvement in PADL was seen for both groups [mean difference (95% confidence interval): land group 993 (358 to 1628) steps/day; water group 1669 (404 to 2934) steps/day]. Significant improvements were also seen in inspiratory, expiratory and peripheral muscle strength; maximal and submaximal exercise capacity; quality of life and functional status for both groups. There were no significant improvements in lung function, body composition, and symptoms of anxiety and depression for either group. No difference was found in the magnitude of improvement between the two types of training for any outcome. CONCLUSION: High-intensity exercise training in water generates similar effects compared with training on land in patients with moderate-to-severe COPD, rendering it an equally beneficial therapeutic option for this population. CLINICAL TRIAL REGISTRATION NUMBER: NCT01691131.


Assuntos
Terapia por Exercício/métodos , Doença Pulmonar Obstrutiva Crônica/reabilitação , Água , Atividades Cotidianas , Idoso , Idoso de 80 Anos ou mais , Composição Corporal , Comorbidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Força Muscular , Resistência Física , Qualidade de Vida , Espirometria , Índices de Gravidade do Trauma
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