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1.
Am J Hum Biol ; 36(1): e23978, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37563889

RESUMO

OBJECTIVES: (1) To examine the muscle thickness of various muscle groups of the body to estimate the absolute and relative skeletal muscle mass (SM) in competitive physique-based athletes (Bodybuilding, 212 Bodybuilding, Bikini, and Physique divisions) and (2) to compare values across various divisions of competition and to resistance trained and non-resistance trained individuals. METHODS: Eight competitive physique-based athletes (2 M and 6 F), two recreationally resistance trained (1 M and 1 F) and two non-resistance trained (1 M and 1 F) participants had muscle thickness measured by ultrasound at nine sites on the anterior and posterior aspects of the body. SM was estimated from an ultrasound-derived prediction equation and SM index was used to adjust for the influence of standing height (i.e., divided by height squared). RESULTS: SM values ranged from 19.6 to 60.4 kg in the eight competitive physique-based athletes and 16.1 to 32.6 kg in the four recreationally resistance trained and non-resistance trained participants. SM index ranged from 7.2 to 17.9 kg/m2 in the eight competitive physique-based athletes and 5.8 to 9.3 kg/m2 in the four recreationally resistance trained and non-resistance trained participants. CONCLUSION: Overall, varying magnitudes of SM and SM index were present across competitors and their respective divisions of bodybuilding. The Men's Open Bodybuilder in the present study had greater values of total SM and SM index compared to previously published values in the literature. Our data provides insight into the extent of SM present in this population and further extends the discussion regarding SM accumulation in humans.


Assuntos
Estatura , Músculo Esquelético , Masculino , Humanos , Músculo Esquelético/fisiologia , Atletas , Composição Corporal/fisiologia
2.
J Musculoskelet Neuronal Interact ; 23(4): 377-385, 2023 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-38037356

RESUMO

OBJECTIVES: This study compared muscle growth in response to very low load resistance training with direct pulsed current (DPC) stimulation and traditional high load training. METHODS: Twenty-six resistance trained individuals had each leg assigned to one of two unilateral knee extension protocols: 1) 4 sets of 20 repetitions at ~10% one-repetition maximum (1RM) and inter-set rest periods of 30 s (DPC) and 2) 4 sets to muscular failure at ~70% 1RM (TRAD). Muscle thickness (MTH), 1RM strength, and local muscular endurance (LME) were measured before and after 8-weeks of training. An alpha level of 0.05 was used for all comparisons. RESULTS: MTH increased similarly between TRAD and DPC at the 50% (0.24 cm, 95%CI: 0.11-0.36), and the 60% anterior sites (0.25 cm, 95%CI: 0.10-.040), as well as the lateral (0.25 cm, 95%CI: 0.10-.040) and medial sites (0.21 cm, 95%CI: 0.10-0.31), but was greater for TRAD at the 40% anterior site (0.3 cm, 95%CI: 0.16-0.43). Changes in 1RM were greater for TRAD (10.2 kg, 95%CI: 5.8-14.4). LME increased similarly between protocols (5 repetitions, 95%CI: 3-7). CONCLUSIONS: The current data suggest that very low load knee extension resistance training with DPC could be a viable training strategy for promoting skeletal muscle growth and local muscular endurance.


Assuntos
Músculo Esquelético , Treinamento Resistido , Humanos , Músculo Esquelético/fisiologia , Treinamento Resistido/métodos , Força Muscular/fisiologia , Articulação do Joelho
3.
Langenbecks Arch Surg ; 408(1): 268, 2023 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-37418033

RESUMO

BACKGROUND: Incisional hernia (IH) is the main complication after laparotomy. In an attempt to reduce this complication, mesh techniques and studies in which the closure technique is modified have been proposed. Both types are characterized by comparison with the closure described as standard or conventional: 1 × 1, mass, and continuous closure. For this study, modified closure techniques (MCTs) were considered as those techniques in which an extra suture is placed (reinforced tension line (RTL), retention), the closure point is modified in distance (small bites) or shape (CLDC, Smead Jones, interrupted, Cardiff point) and which aim to reduce these complications. The objective of this network meta-analysis (NMA) was to evaluate the effectiveness of MCTs for reducing the incidence of IH and abdominal wound dehiscence (AWD) to provide objective support for their recommendation. METHODS: An NMA was performed according to the PRISMA-NMA guidelines. The primary objective was to determine the incidence of IH and AWD, and the secondary objective was to determine the incidence of postoperative complications. Only published clinical trials were included. The risk of bias was analyzed, and the random-effects model was used to determine statistical significance. RESULTS: Twelve studies comparing 3540 patients were included. The incidence of HI was lower in RTL, retention suture, and small bites, these techniques showed statistical differences with pooled ORs (95% CI) of 0.28 (0.09-0.83), 0.28 (0.13-0.62), and 0.44 (0.31-0.62), respectively. Associated complications, including hematoma, seroma, and postoperative pain, could not be analyzed; however, MCTs did not increase the risk of surgical site infection. CONCLUSION: Small bites, RTL, and retention sutures decreased the prevalence of IH. RTL and retention suture decreased the prevalence of AWD. RTL was the best technique as it reduced both complications (IH and AWD) and had the best SUCRA and P-scores, and the number needed to treat (NNT) for net effect was 3. REGISTRATION: This study was prospectively registered in the PROSPERO database under registration number CRD42021231107.


Assuntos
Traumatismos Abdominais , Técnicas de Fechamento de Ferimentos Abdominais , Hérnia Incisional , Humanos , Hérnia Incisional/epidemiologia , Hérnia Incisional/etiologia , Hérnia Incisional/prevenção & controle , Laparotomia/efeitos adversos , Laparotomia/métodos , Metanálise em Rede , Técnicas de Sutura/efeitos adversos , Abdome , Suturas/efeitos adversos , Técnicas de Fechamento de Ferimentos Abdominais/efeitos adversos , Deiscência da Ferida Operatória/epidemiologia , Deiscência da Ferida Operatória/etiologia , Deiscência da Ferida Operatória/prevenção & controle
4.
J Strength Cond Res ; 37(12): 2381-2388, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-37535935

RESUMO

ABSTRACT: Hammert, WB, Moreno, EN, Martin, CC, Jessee, MB, and Buckner, SL. Skeletal muscle adaptations to high-load resistance training with pre-exercise blood flow restriction. J Strength Cond Res 37(12): 2381-2388, 2023-This study aimed to determine if blood flow restriction (BFR) could augment adaptations to a high-load training protocol that was inadequate for muscle growth. Forty nontrained individuals had each arm assigned to 1 of 3 elbow flexion protocols: (a) high-load resistance training [TRAD; 4 sets to muscular failure at 70% 1 repetition maximum (1RM)], (b) low repetition high-load resistance training with pre-exercise BFR (PreBFR; 4 sets of 3 repetitions at 70% 1RM + 3 min of pre-exercise BFR), and (c) low repetition high-load resistance training (LRTRAD); 4 sets of 3 repetitions at 70% 1RM). Muscle thickness (MT), 1RM strength, and local muscular endurance (LME) of the elbow flexors were measured before and after 8 weeks. An alpha level of 0.05 was used for all comparisons. For the 50% site, MT increased for TRAD (0.211 cm, 95% confidence interval [95% CI]: 0.143-0.280), PreBFR (0.105 cm, 95% CI: 0.034-0.175), and LRTRAD (0.073 cm, 95% CI: 0.000-0.146). The change for TRAD was greater than PreBFR and LRTRAD. For the 60% site, MT increased for TRAD (0.235 cm, 95% CI: 0.153-0.317), PreBFR (0.097 cm, 95% CI: 0.014-0.180), and LRTRAD (0.082 cm, 95% CI: 0.000-0.164). The change for TRAD was greater than PreBFR and LRTRAD. For the 70% site MT increased for TRAD (0.308 cm, 95% CI: 0.247-0.369), PreBFR (0.103 cm, 95% CI: 0.041-0.166), and LRTRAD (0.070 cm, 95% CI: 0.004-0.137). The change for TRAD was greater than PreBFR and LRTRAD. One repetition maximum and LME significantly increased for each condition, with no differences between conditions. Collapsed across conditions 1RM strength increased 2.094 kg (95% CI: 1.771-2.416) and LME increased 7.0 repetitions (95% CI: 5.7-8.3). In conclusion, the application of BFR to low-repetition, high-load training did not enhance the adaptative response.


Assuntos
Músculo Esquelético , Treinamento Resistido , Humanos , Músculo Esquelético/fisiologia , Treinamento Resistido/métodos , Força Muscular/fisiologia , Hemodinâmica , Cotovelo , Fluxo Sanguíneo Regional/fisiologia
5.
Gastroenterol Hepatol ; 46(6): 425-438, 2023.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-36243249

RESUMO

BACKGROUND: Retrospective studies suggest that coronavirus disease (COVID-19) commonly involves gastrointestinal (GI) symptoms and complications. Our aim was to prospectively evaluate GI manifestations in patients hospitalized for COVID-19. METHODS: This international multicentre prospective cohort study recruited COVID-19 patients hospitalized at 31 centres in Spain, Mexico, Chile, and Poland, between May and September 2020. Patients were followed-up until 15 days post-discharge and completed comprehensive questionnaires assessing GI symptoms and complications. A descriptive analysis as well as a bivariate and multivariate analysis were performer using binary logistic regression. p<0.05 was considered significant. RESULTS: Eight hundred twenty-nine patients were enrolled; 129 (15.6%) had severe COVID-19, 113 (13.7%) required ICU admission, and 43 (5.2%) died. Upon admission, the most prevalent GI symptoms were anorexia (n=413; 49.8%), diarrhoea (n=327; 39.4%), nausea/vomiting (n=227; 27.4%), and abdominal pain (n=172; 20.7%), which were mild/moderate throughout the disease and resolved during follow-up. One-third of patients exhibited liver injury. Non-severe COVID-19 was associated with ≥2 GI symptoms upon admission (OR 0.679; 95% CI 0.464-0.995; p=0.046) or diarrhoea during hospitalization (OR 0.531; 95% CI 0.328-0.860; p=0.009). Multivariate analysis revealed that worse hospital outcomes were not independently associated with liver injury or GI symptoms. CONCLUSION: GI symptoms were more common than previously documented, and were mild, rapidly resolved, and not independently associated with COVID-19 severity. Liver injury was a frequent complication in hospitalized patients not independently associated with COVID-19 severity.


Assuntos
COVID-19 , Gastroenteropatias , Humanos , COVID-19/complicações , Estudos Retrospectivos , SARS-CoV-2 , Estudos Prospectivos , Assistência ao Convalescente , Alta do Paciente , Gastroenteropatias/etiologia , Gastroenteropatias/complicações , Diarreia/epidemiologia , Diarreia/etiologia
6.
Small ; 17(26): e2101100, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34081416

RESUMO

Multiple studies have reported the observation of electro-synaptic response in different metal/insulator/metal devices. However, most of them analyzed large (>1 µm2 ) devices that do not meet the integration density required by industry (1010  devices/mm2 ). Some studies emploied a scanning tunneling microscope (STM) to explore nano-synaptic response in different materials, but in this setup there is a nanogap between the insulator and one of the metallic electrodes (i.e., the STM tip), not present in real devices. Here, it is demonstrated how to use conductive atomic force microscopy to explore the presence and quality of nano-synaptic response in confined areas <50 nm2 . Graphene oxide (GO) is selected due to its easy fabrication. Metal/GO/metal nano-synapses exhibit potentiation and paired pulse facilitation with low write current levels <1 µA (i.e., power consumption ≈3 µW), controllable excitatory post-synaptic currents, and long-term potentiation and depression. The results provide a new method to explore nano-synaptic plasticity at the nanoscale, and point to GO as an important candidate for the fabrication of ultrasmall (<50 nm2 ) electronic synapses fulfilling the integration density requirements of neuromorphic systems.


Assuntos
Grafite , Sinapses , Microscopia de Força Atômica , Plasticidade Neuronal
7.
EMBO J ; 32(21): 2884-95, 2013 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-24121311

RESUMO

Elucidating molecular links between cell-fate regulatory networks and dynamic patterning modules is a key for understanding development. Auxin is important for plant patterning, particularly in roots, where it establishes positional information for cell-fate decisions. PIN genes encode plasma membrane proteins that serve as auxin efflux transporters; mutations in members of this gene family exhibit smaller roots with altered root meristems and stem-cell patterning. Direct regulators of PIN transcription have remained elusive. Here, we establish that a MADS-box gene (XAANTAL2, XAL2/AGL14) controls auxin transport via PIN transcriptional regulation during Arabidopsis root development; mutations in this gene exhibit altered stem-cell patterning, root meristem size, and root growth. XAL2 is necessary for normal shootward and rootward auxin transport, as well as for maintaining normal auxin distribution within the root. Furthermore, this MADS-domain transcription factor upregulates PIN1 and PIN4 by direct binding to regulatory regions and it is required for PIN4-dependent auxin response. In turn, XAL2 expression is regulated by auxin levels thus establishing a positive feedback loop between auxin levels and PIN regulation that is likely to be important for robust root patterning.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/fisiologia , Ácidos Indolacéticos/metabolismo , Proteínas de Domínio MADS/metabolismo , Proteínas de Membrana Transportadoras/genética , Proteínas de Arabidopsis/genética , Proteínas de Domínio MADS/genética , Proteínas de Membrana Transportadoras/metabolismo , Raízes de Plantas/fisiologia
8.
Thorax ; 72(5): 460-471, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-27701117

RESUMO

BACKGROUND: Pulmonary hypertension (PH) is frequently observed in patients with acute respiratory distress syndrome (ARDS) and it is associated with an increased risk of mortality. Both acid sphingomyelinase (aSMase) activity and interleukin 6 (IL-6) levels are increased in patients with sepsis and correlate with worst outcomes, but their role in pulmonary vascular dysfunction pathogenesis has not yet been elucidated. Therefore, the aim of this study was to determine the potential contribution of aSMase and IL-6 in the pulmonary vascular dysfunction induced by lipopolysaccharide (LPS). METHODS: Rat or human pulmonary arteries (PAs) or their cultured smooth muscle cells (SMCs) were exposed to LPS, SMase or IL-6 in the absence or presence of a range of pharmacological inhibitors. The effects of aSMase inhibition in vivo with D609 on pulmonary arterial pressure and inflammation were assessed following intratracheal administration of LPS. RESULTS: LPS increased ceramide and IL-6 production in rat pulmonary artery smooth muscle cells (PASMCs) and inhibited pulmonary vasoconstriction induced by phenylephrine or hypoxia (HPV), induced endothelial dysfunction and potentiated the contractile responses to serotonin. Exogenous SMase and IL-6 mimicked the effects of LPS on endothelial dysfunction, HPV failure and hyperresponsiveness to serotonin in PA; whereas blockade of aSMase or IL-6 prevented LPS-induced effects. Finally, administration of the aSMase inhibitor D609 limited the development of endotoxin-induced PH and ventilation-perfusion mismatch. The protective effects of D609 were validated in isolated human PAs. CONCLUSIONS: Our data indicate that aSMase and IL-6 are not simply biomarkers of poor outcomes but pathogenic mediators of pulmonary vascular dysfunction in ARDS secondary to Gram-negative infections.


Assuntos
Hipertensão Pulmonar/metabolismo , Interleucina-6/metabolismo , Interleucina-6/farmacologia , Artéria Pulmonar/metabolismo , Esfingomielina Fosfodiesterase/metabolismo , Esfingomielina Fosfodiesterase/farmacologia , Animais , Hidrocarbonetos Aromáticos com Pontes/farmacologia , Células Cultivadas , Ceramidases/metabolismo , Modelos Animais de Doenças , Imunofluorescência , Humanos , Interleucina-1beta/metabolismo , Lipopolissacarídeos , Masculino , Músculo Liso Vascular/citologia , Norbornanos , Ratos , Ratos Wistar , Tiocarbamatos , Tionas/farmacologia , Vasoconstrição/efeitos dos fármacos
9.
Clin Transplant ; 31(1)2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27801525

RESUMO

Complement component 3 (C3) presents both slow (C3S) and fast (C3F) variants, which can be locally produced and activated by immune system cells. We studied C3 recipient variants in 483 liver transplant patients by RT-PCR-HRM to determine their effect on graft outcome during the first year post-transplantation. Allograft survival was significantly decreased in C3FF recipients (C3SS 95% vs C3FS 91% vs C3FF 83%; P=.01) or C3F allele carriers (C3F absence 95% vs C3F presence 90%, P=.02). C3FF genotype or presence of C3F allele independently increased risk for allograft loss (OR: 2.38, P=.005 and OR: 2.66, P=.02, respectively). C3FF genotype was more frequent among patients whose first infection was of viral etiology (C3SS 13% vs C3FS 18% vs C3FF 32%; P=.04) and independently increased risk for post-transplant viral infections (OR: 3.60, P=.008). On the other hand, C3FF and C3F protected from rejection events (OR: 0.54, P=.03 and OR: 0.63, P=.047, respectively). Differences were not observed in hepatitis C virus recurrence or patient survival. In conclusion, we show that, independently from C3 variants produced by donor liver, C3F variant from recipient diminishes allograft survival, increases susceptibility to viral infections, and protects from rejection after transplantation. C3 genotyping of liver recipients may be useful to stratify risk.


Assuntos
Complemento C3b/genética , Rejeição de Enxerto/prevenção & controle , Transplante de Fígado/efeitos adversos , Polimorfismo Genético , Doadores de Tecidos , Transplantados , Viroses/etiologia , Adolescente , Adulto , Idoso , Biomarcadores/metabolismo , Criança , Pré-Escolar , Feminino , Seguimentos , Rejeição de Enxerto/etiologia , Sobrevivência de Enxerto , Humanos , Lactente , Recém-Nascido , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias , Prognóstico , Isoformas de Proteínas , Fatores de Risco , Transplante Homólogo , Viroses/patologia , Adulto Jovem
10.
Ann Vasc Surg ; 31: 208.e1-4, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26631771

RESUMO

Aortoiliac occlusive disease coincident with a congenital ectopic pelvic kidney is a rare occurrence. Traditionally, the treatment has been open aortobifemoral repair with reimplantation of the renal artery. We present a patient with Trans-Atlantic Inter-Society Consensus (TASC) D bilateral aortoiliac occlusive disease, an ectopic pelvic kidney, and prohibitive medical comorbidities. We describe a totally endovascular repair using a chronic total occlusion crossing device, a luminal re-entry device, and balloon-mounted covered stents to revascularize the lower extremities and the ectopic pelvic kidney. We discuss various aspects of this endovascular approach as the incidence of patients with TASC D lesions and prohibitive comorbidities continue to rise.


Assuntos
Doenças da Aorta/cirurgia , Arteriopatias Oclusivas/cirurgia , Coristoma/complicações , Procedimentos Endovasculares , Artéria Ilíaca/cirurgia , Rim , Procedimentos de Cirurgia Plástica , Doenças da Aorta/complicações , Doenças da Aorta/diagnóstico , Aortografia/métodos , Arteriopatias Oclusivas/complicações , Arteriopatias Oclusivas/diagnóstico , Coristoma/diagnóstico , Procedimentos Endovasculares/instrumentação , Feminino , Humanos , Artéria Ilíaca/diagnóstico por imagem , Pessoa de Meia-Idade , Procedimentos de Cirurgia Plástica/instrumentação , Stents , Tomografia Computadorizada por Raios X , Resultado do Tratamento
11.
Ann Vasc Surg ; 29(5): 1021.e9-1021.e12, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25770382

RESUMO

Abdominal aortic aneurysm complicated by a horseshoe kidney (HSK, fused kidney) represents a unique challenge for repair. Renal arteries arising from the aneurysmal aorta can further complicate intervention. Reports exist describing the repair of these complex anatomies using fenestrated endografts, hybrid open repairs (debranching), and open aneurysmorrhaphy with preservation of renal circulation. We describe an extra-anatomic, fully endovascular repair of an abdominal aortic aneurysm with a HSK partially supplied by a renal artery arising from the aneurysm. We successfully applied aortouni-iliac endografting, femorofemoral bypass, and retrograde renal artery perfusion via the contralateral femoral artery to exclude the abdominal aortic aneurysm and preserve circulation to the HSK.


Assuntos
Aneurisma da Aorta Abdominal/cirurgia , Implante de Prótese Vascular/métodos , Procedimentos Endovasculares/métodos , Rim Fundido/complicações , Idoso de 80 Anos ou mais , Angiografia , Aneurisma da Aorta Abdominal/complicações , Aneurisma da Aorta Abdominal/diagnóstico , Humanos , Imageamento Tridimensional , Masculino , Radiografia Abdominal , Tomografia Computadorizada por Raios X
12.
Appl Opt ; 53(9): 1802-7, 2014 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-24663456

RESUMO

A low-cost, direct fabrication technique with a micrometer range resolution has been implemented for rapid prototyping of optical masks for photolithography and structured light and diffraction optics applications. Using a setup based on the optical unit of a compact disc-digital versatile disc burner, a low-energy infrared laser beam was focused on a thin polymeric layer with embedded absorbing carbon nanopowder coated on a transparent glass substrate. This allowed for the generation of a custom-made transparent pattern in a computer numerical control fashion. In addition to its great simplicity and repeatability, the method also enables grayscale contrasts for each pixel individually, and fabricated masks proved to resist high intensities.

13.
BMC Med Imaging ; 14: 22, 2014 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-24920158

RESUMO

BACKGROUND: Endobronchial ultrasonography (EBUS) has been applied as a routine procedure for the diagnostic of hiliar and mediastinal nodes. The authors assessed the relationship between the echographic appearance of mediastinal nodes, based on endobronchial ultrasound images, and the likelihood of malignancy. METHODS: The images of twelve malignant and eleven benign nodes were evaluated. A previous processing method was applied to improve the quality of the images and to enhance the details. Texture and morphology parameters analyzed were: the image texture of the echographies and a fractal dimension that expressed the relationship between area and perimeter of the structures that appear in the image, and characterizes the convoluted inner structure of the hiliar and mediastinal nodes. RESULTS: Processed images showed that relationship between log perimeter and log area of hilar nodes was lineal (i.e. perimeter vs. area follow a power law). Fractal dimension was lower in the malignant nodes compared with non-malignant nodes (1.47(0.09), 1.53(0.10) mean(SD), Mann-Whitney U test p < 0.05)). CONCLUSION: Fractal dimension of ultrasonographic images of mediastinal nodes obtained through endobronchial ultrasound differ in malignant nodes from non-malignant. This parameter could differentiate malignat and non-malignat mediastinic and hiliar nodes.


Assuntos
Broncoscopia/métodos , Linfonodos/diagnóstico por imagem , Diagnóstico Diferencial , Diagnóstico por Imagem , Fractais , Humanos , Processamento de Imagem Assistida por Computador , Linfonodos/anatomia & histologia , Conceitos Matemáticos , Imagem Multimodal , Ultrassonografia
14.
Physiol Meas ; 45(6)2024 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-38838705

RESUMO

Objective. To compare the acute physiological and perceptual responses to blood flow restriction (BFR) exercise using a traditional research device or novel, automated system.Methods. Forty-four resistance trained individuals performed four sets of unilateral elbow flexion exercise (30% one-repetition maximum) to volitional failure using two distinct restrictive devices [SmartCuffs PRO BFR Model (SMARTCUFF), Hokanson E20 Rapid Inflation device (HOKANSON)] and with two levels of BFR [40% limb occlusion pressure (LOP), 80% LOP]. Blood pressure (BP), muscle thickness (MT), and isometric strength (ISO) were assessed prior to and following exercise. Perceptual responses [ratings of perceived exertion (RPE), discomfort] were assessed prior to exercise and following each exercise set.Main results. Data are displayed as means (SD). Immediately following exercise with 40% LOP, there were no statistical differences between devices for BP, MT, and ISO. However, only following Set 1 of exercise, RPE was greater with SMARTCUFF compared to HOKANSON (p< 0.05). In addition, only following Set 2 of exercise, discomfort was greater with HOKANSON compared to SMARTCUFF (p< 0.001). Immediately following exercise with 80% LOP, there were no statistical differences between devices for BP, MT, and ISO. However, only following Set 4 of exercise, RPE was greater with HOKANSON compared to SMARTCUFF (p< 0.05). In addition, following all exercise sets, discomfort was greater with HOKANSON compared to SMARTCUFF (p< 0.001). For repetitions completed with 40% LOP there were no statistical differences between SMARTCUFF and HOKANSON across any exercise sets. For repetitions completed with 80% LOP there were no statistical differences between SMARTCUFF and HOKANSON across Set 1 of exercise (p= 0.34), however, for Sets 2-4 of exercise, significantly greater number of repetitions were completed during SMARTCUFF than HOKANSON.Significance. The present study provides valuable insight into the efficacy of a novel, automated BFR system (SMARTCUFF) eliciting comparable acute physiological responses to BFR exercise and in some cases favorable perceptual responses when compared to a traditional research device (HOKANSON).


Assuntos
Automação , Exercício Físico , Percepção , Fluxo Sanguíneo Regional , Humanos , Masculino , Feminino , Exercício Físico/fisiologia , Fluxo Sanguíneo Regional/fisiologia , Percepção/fisiologia , Adulto Jovem , Adulto , Pressão Sanguínea/fisiologia , Treinamento Resistido/instrumentação
15.
ACS Appl Electron Mater ; 6(2): 1424-1433, 2024 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-38435806

RESUMO

Resistive switching devices based on the Au/Ti/TiO2/Au stack were developed. In addition to standard electrical characterization by means of I-V curves, scanning thermal microscopy was employed to localize the hot spots on the top device surface (linked to conductive nanofilaments, CNFs) and perform in-operando tracking of temperature in such spots. In this way, electrical and thermal responses can be simultaneously recorded and related to each other. In a complementary way, a model for device simulation (based on COMSOL Multiphysics) was implemented in order to link the measured temperature to simulated device temperature maps. The data obtained were employed to calculate the thermal resistance to be used in compact models, such as the Stanford model, for circuit simulation. The thermal resistance extraction technique presented in this work is based on electrical and thermal measurements instead of being indirectly supported by a single fitting of the electrical response (using just I-V curves), as usual. Besides, the set and reset voltages were calculated from the complete I-V curve resistive switching series through different automatic numerical methods to assess the device variability. The series resistance was also obtained from experimental measurements, whose value is also incorporated into a compact model enhanced version.

16.
Clin Physiol Funct Imaging ; 43(2): 109-119, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36401343

RESUMO

PURPOSE: The purpose of this study is to examine the acute muscular and cardiovascular responses to applying blood flow restriction (BFR) before high-load training. METHODS: Forty trained individuals visited the lab on three occasions. On Visit 1, participants completed paperwork and performed strength assessments. During Visits 2 and 3, participants completed four exercise conditions (one in each arm during each visit) as follows: (1) traditional resistance training (TRAD), (2) low load training with BFR (LLBFR), (3) low repetition high load training with pre-exercise BFR (PreBFR), and (4) low repetition traditional training (LRTRAD). Blood pressure, muscle thickness (MT), and isometric strength (ISO) were measured before and after exercise. RESULTS: Data are displayed as means (SD). Immediately following exercise, MT in TRAD was greater compared with PreBFR (mean difference = 0.18[0.30] cm, p < 0.001) and LRTRAD (mean difference = 0.28[0.30] cm, p < 0.001). In addition, LLBFR demonstrated greater MT compared with PreBFR (mean difference = 0.24[0.30] cm, p < 0.001]. Immediately following exercise, ISO was lower in TRAD compared with PreBFR (mean difference = 33.8[46.9]N, p < 0.001) and the LRTRAD condition (mean difference = 32.8[50.4]N, p < 0.001). In addition, ISO was lower in LLBFR compared with PreBFR (mean difference = 43.9 [47.4]N, p < 0.001) and LRTRAD (mean difference = 42.9 [43.8]N, p < 0.001). Immediately following exercise, systolic blood pressure was greater in TRAD compared with PreBFR and LRTRAD. CONCLUSION: The application of BFR before engaging in high-load training does not seem to augment the muscular responses to exercise when compared with traditional high loads alone; however, it may pose less demand on the cardiovascular system.


Assuntos
Sistema Cardiovascular , Treinamento Resistido , Humanos , Músculo Esquelético/fisiologia , Força Muscular/fisiologia , Fluxo Sanguíneo Regional/fisiologia , Hemodinâmica
17.
Micromachines (Basel) ; 14(3)2023 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-36985037

RESUMO

A methodology to estimate the device temperature in resistive random access memories (RRAMs) is presented. Unipolar devices, which are known to be highly influenced by thermal effects in their resistive switching operation, are employed to develop the technique. A 3D RRAM simulator is used to fit experimental data and obtain the maximum and average temperatures of the conductive filaments (CFs) that are responsible for the switching behavior. It is found that the experimental CFs temperature corresponds to the maximum simulated temperatures obtained at the narrowest sections of the CFs. These temperature values can be used to improve compact models for circuit simulation purposes.

18.
Animals (Basel) ; 13(12)2023 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-37370493

RESUMO

Guide dogs work for extended periods and are exposed to multiple environmental stimuli that could lead to higher stress compared with companion dogs. Cortisol is the main hormone associated with stress in most mammals. This study included seven guide dogs and seven same-breed dogs that were trained as guide dogs but became companion dogs to compare their salivary cortisol levels before, during, and after a period of social isolation and exposure to a 110-decibel gunshot sound. Each dog was left alone in an empty room for 60 min. After 15 min, the dogs were exposed to the sound. We collected four saliva samples from each dog. The first one was taken 5 min before starting the social isolation period, and the following ones at 15, 30, and 45 min after the test started. A two-way ANOVA was used to compare the group effect and the time effect during isolation and noise exposure. The results showed higher levels of cortisol in the guide dogs compared with the companion dogs throughout the test. No differences were found in time or in the interaction between time and group. This suggests that being a guide dog increases levels of basal cortisol when compared with dogs that live as companion animals and family members.

19.
Exp Physiol ; 97(5): 676-86, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22247283

RESUMO

Although type 1 and type 2 diabetes are strongly associated with systemic cardiovascular morbidity, the relationship with pulmonary vascular disease had been almost disregarded until recent epidemiological data revealed that diabetes might be a risk factor for pulmonary hypertension. Recent experimental studies suggest that diabetes induces changes in lung function insufficient to elevate pulmonary pressure. The aim of this study was to assess the effects of diabetes on the sensitivity to other risk factors for pulmonary hypertension. We therefore analysed the effects of the combination of diabetes with exposure to moderate hypoxia on classical markers of pulmonary hypertension. Control (saline-treated) and diabetic (70 mg kg(-1) streptozotocin-treated) male Wistar-Kyoto rats were followed for 4 weeks and exposed to normoxia or moderate normobaric hypoxia (14%) for another 2 weeks. Hypoxia, but not diabetes, strongly reduced voltage-gated potassium currents, whereas diabetes, but not hypoxia, induced pulmonary artery endothelial dysfunction. Both factors independently induced pulmonary vascular remodelling and downregulated the lung bone morphogenetic protein receptor type 2. However, diabetes, but not hypoxia, induced pulmonary infiltration of macrophages, which was markedly increased when both factors were combined. Diabetes plus hypoxia induced a modest increase in diastolic and mean pulmonary artery pressure and right ventricular weight, while each of the two factors alone had no significant effect. The pattern of changes in markers of pulmonary hypertension was different for moderate hypoxia and diabetes, with no synergic effect except for macrophage recruitment, and the combination of both factors was required to induce a moderate elevation in pulmonary arterial pressure.


Assuntos
Diabetes Mellitus Tipo 1/complicações , Hipertensão Pulmonar/etiologia , Hipóxia/complicações , Animais , Receptores de Proteínas Morfogenéticas Ósseas Tipo II/metabolismo , Diabetes Mellitus Experimental/complicações , Regulação para Baixo , Hipertrofia Ventricular Direita/etiologia , Pulmão/patologia , Pulmão/fisiopatologia , Macrófagos/imunologia , Masculino , Artéria Pulmonar/patologia , Artéria Pulmonar/fisiopatologia , Ratos , Ratos Endogâmicos WKY , Doenças Vasculares/etiologia
20.
BMC Gastroenterol ; 12: 114, 2012 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-22909075

RESUMO

BACKGROUND: Portal vein thrombosis is a frequent complication in end-stage cirrhosis with a considerable peri-operative risk for liver transplant candidates. We aimed to characterize the pre-transplant portal vein thrombosis in a cohort of liver transplant recipients, and to identify independent risk factors for this complication. METHODS: 380 consecutive primary orthotopic liver transplants were performed in the Digestive Surgery Department of "12 de Octubre" Hospital (Madrid, Spain), between January 2001 and December 2006. The main risk factors considered were smoking, obesity, metabolic disorders, previous immobility, surgery or trauma, nephrotic syndrome, associated tumor, inflammatory disease, neoplasm myeloprolipherative. Furthermore we have reported genetic thrombophilia results for 271 recipients. RESULTS: Sixty-two (16.3%) patients developed pre-transplant portal vein thrombosis and its presence had no impact in the overall survival of liver recipients. Obesity was the only independent risk factor for pre-transplant portal vein thrombosis. CONCLUSION: We recommend close control of cardiovascular factors in patients with liver cirrhosis in order to avoid associated thrombosis.


Assuntos
Cirrose Hepática/epidemiologia , Transplante de Fígado , Obesidade/epidemiologia , Veia Porta , Trombose Venosa/epidemiologia , Adolescente , Adulto , Idoso , Estudos de Coortes , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Fumar/efeitos adversos , Trombofilia/genética
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