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2.
J Endocrinol Invest ; 46(12): 2583-2599, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37286863

RESUMO

PURPOSE/METHODS: The determination of tumour biomarkers is paramount to advancing personalized medicine, more so in rare tumours like medullary thyroid carcinoma (MTC), whose diagnosis is still challenging. The aim of this study was to identify non-invasive circulating biomarkers in MTC. To achieve this goal, paired MTC tissue and plasma extracellular vesicle samples were collected from multiple centres and microRNA (miRNA) expression levels were evaluated. RESULTS: The samples from a discovery cohort of 23 MTC patients were analysed using miRNA arrays. Lasso logistic regression analysis resulted in the identification of a set of circulating miRNAs as diagnostic biomarkers. Among them, miR-26b-5p and miR-451a, were highly expressed and their expression decreased during follow-up in disease-free patients in the discovery cohort. Circulating miR-26b-5p and miR-451a were validated using droplet digital PCR in a second independent cohort of 12 MTC patients. CONCLUSION: This study allowed the identification and validation of a signature of two circulating miRNAs, miR-26b-5p and miR-451a, in two independent cohorts reporting a significant diagnostic performance for MTC. The results of this study offer advancements in molecular diagnosis of MTC proposing a novel non-invasive tool to use in precision medicine.


Assuntos
MicroRNA Circulante , MicroRNAs , Neoplasias da Glândula Tireoide , Humanos , MicroRNAs/genética , Neoplasias da Glândula Tireoide/diagnóstico , Neoplasias da Glândula Tireoide/genética , Neoplasias da Glândula Tireoide/patologia , Biomarcadores , Biomarcadores Tumorais/metabolismo
3.
Braz J Med Biol Res ; 55: e12118, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35857999

RESUMO

The goal of the present study was to compare pulmonary function test (PFT) and cardiopulmonary exercise test (CPET) performance in COVID-19 survivors with a control group (CG). This was a cross-sectional study. Patients diagnosed with COVID-19, without severe signs and symptoms, were evaluated one month after the infection. Healthy volunteers matched for sex and age constituted the control group. All volunteers underwent the following assessments: i) clinical evaluation, ii) PTF; and iii) CPET on a cycle ergometer. Metabolic variables were measured by the CareFusion Oxycon Mobile device. In addition, heart rate responses, peak systolic and diastolic blood pressure, and perceived exertion were recorded. Twenty-nine patients with COVID-19 and 18 healthy control subjects were evaluated. Surviving patients of COVID-19 had a mean age of 40 years and had higher body mass index and persistent symptoms compared to the CG (P<0.05), but patients with COVID-19 had more comorbidities, number of medications, and greater impairment of lung function (P<0.05). Regarding CPET, patients surviving COVID-19 had reduced peak workload, oxygen uptake (V̇O2), carbon dioxide output (V̇CO2), circulatory power (CP), and end-tidal pressure for carbon dioxide (PETCO2) (P<0.05). Additionally, survivors had depressed chronotropic and ventilatory responses, low peak oxygen saturation, and greater muscle fatigue (P<0.05) compared to CG. Despite not showing signs and symptoms of severe disease during infection, adult survivors had losses of lung function and cardiorespiratory capacity one month after recovery from COVID-19. In addition, cardiovascular, ventilatory, and lower limb fatigue responses were the main exercise limitations.


Assuntos
COVID-19 , Aptidão Cardiorrespiratória , Adulto , Dióxido de Carbono/metabolismo , Estudos Transversais , Teste de Esforço , Tolerância ao Exercício/fisiologia , Humanos , Pessoa de Meia-Idade , Consumo de Oxigênio/fisiologia
4.
Braz. j. med. biol. res ; 55: e12118, 2022. tab, graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1384139

RESUMO

The goal of the present study was to compare pulmonary function test (PFT) and cardiopulmonary exercise test (CPET) performance in COVID-19 survivors with a control group (CG). This was a cross-sectional study. Patients diagnosed with COVID-19, without severe signs and symptoms, were evaluated one month after the infection. Healthy volunteers matched for sex and age constituted the control group. All volunteers underwent the following assessments: i) clinical evaluation, ii) PTF; and iii) CPET on a cycle ergometer. Metabolic variables were measured by the CareFusion Oxycon Mobile device. In addition, heart rate responses, peak systolic and diastolic blood pressure, and perceived exertion were recorded. Twenty-nine patients with COVID-19 and 18 healthy control subjects were evaluated. Surviving patients of COVID-19 had a mean age of 40 years and had higher body mass index and persistent symptoms compared to the CG (P<0.05), but patients with COVID-19 had more comorbidities, number of medications, and greater impairment of lung function (P<0.05). Regarding CPET, patients surviving COVID-19 had reduced peak workload, oxygen uptake (V̇O2), carbon dioxide output (V̇CO2), circulatory power (CP), and end-tidal pressure for carbon dioxide (PETCO2) (P<0.05). Additionally, survivors had depressed chronotropic and ventilatory responses, low peak oxygen saturation, and greater muscle fatigue (P<0.05) compared to CG. Despite not showing signs and symptoms of severe disease during infection, adult survivors had losses of lung function and cardiorespiratory capacity one month after recovery from COVID-19. In addition, cardiovascular, ventilatory, and lower limb fatigue responses were the main exercise limitations.

5.
Braz J Med Biol Res ; 54(11): e10974, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34431871

RESUMO

Continuous positive airway pressure (CPAP) has been used to improve gas exchange and diaphragmatic function, among others benefits. Moreover, it can be used to increase exercise tolerance and positively influence ventilatory function and breathing pattern (BP) during exercise. However, there is no information about the long-term effects of CPAP, as an adjunct to an inpatient cardiac rehabilitation (CR) program, on BP and heart rate variability (HRV) of patients after coronary artery bypass grafting surgery (CABG). Twenty patients were allocated to receive, after randomization, standard inpatient CR without CPAP (control group - CG) or CR with CPAP between 10 to 12 cmH2O (CPAP group - CPG) associated with the exercises. Participants were assessed preoperatively and on the discharge day, in the sitting rest position. Outcome measurements included BP variables, collected by respiratory inductive plethysmography, and HRV, collected by polar precision performance. The CPG presented lower values of percent rib cage inspiratory and expiratory contributions to tidal volume (%RCi and %RCe) at discharge time, compared to CG. No statistical differences between groups were observed for HRV variables and both groups presented lower values of these indices, compared to preoperative ones. In this context, the patients who received CPAP throughout the whole rehabilitation program were discharged with a better BP, which could indicate more synchronized breathing. CPAP did not influence cardiac autonomic modulation in the long term.


Assuntos
Pressão Positiva Contínua nas Vias Aéreas , Exercício Físico , Ponte de Artéria Coronária , Frequência Cardíaca , Humanos , Respiração
6.
Braz J Med Biol Res ; 54(10): e10514, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34287574

RESUMO

Exercise intolerance is the hallmark consequence of advanced chronic heart failure (HF). The six-minute step test (6MST) has been considered an option for the six-minute walk test because it is safe, inexpensive, and can be applied in small places. However, its reliability and concurrent validity has still not been investigated in participants with HF with reduced ejection fraction (HFrEF). Clinically stable HFrEF participants were included. Reliability and error measurement were calculated by comparing the first with the second 6MST result. Forty-eight hours after participants underwent the 6MST, they were invited to perform a cardiopulmonary exercise test (CPET) on a cycle ergometer. Concurrent validity was assessed by correlation between number of steps and peak oxygen uptake (V̇O2 peak) at CPET. Twenty-seven participants with HFrEF (60±8 years old and left ventricle ejection fraction of 41±6%) undertook a mean of 94±30 steps in the 6MST. Intra-rater reliability was excellent for 6MST (ICC=0.9), with mean error of 4.85 steps and superior and inferior limits of agreement of 30.6 and -20.9 steps, respectively. In addition, strong correlations between number of steps and CPET workload (r=0.76, P<0.01) and peak V̇O2 (r=0.71, P<0.01) were observed. From simple linear regression the following predictive equations were obtained with 6MST results: V̇O2 peak (mL/min) = 350.22 + (7.333 × number of steps), with R2=0.51, and peak workload (W) = 4.044 + (0.772 × number of steps), with R2=0.58. The 6MST was a reliable and valid tool to assess functional capacity in HFrEF participants and may moderately predict peak workload and oxygen uptake of a CPET.


Assuntos
Teste de Esforço , Insuficiência Cardíaca , Idoso , Tolerância ao Exercício , Insuficiência Cardíaca/diagnóstico , Humanos , Pessoa de Meia-Idade , Consumo de Oxigênio , Reprodutibilidade dos Testes , Volume Sistólico , Teste de Caminhada
7.
Braz. j. med. biol. res ; 54(11): e10974, 2021. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1285663

RESUMO

Continuous positive airway pressure (CPAP) has been used to improve gas exchange and diaphragmatic function, among others benefits. Moreover, it can be used to increase exercise tolerance and positively influence ventilatory function and breathing pattern (BP) during exercise. However, there is no information about the long-term effects of CPAP, as an adjunct to an inpatient cardiac rehabilitation (CR) program, on BP and heart rate variability (HRV) of patients after coronary artery bypass grafting surgery (CABG). Twenty patients were allocated to receive, after randomization, standard inpatient CR without CPAP (control group - CG) or CR with CPAP between 10 to 12 cmH2O (CPAP group - CPG) associated with the exercises. Participants were assessed preoperatively and on the discharge day, in the sitting rest position. Outcome measurements included BP variables, collected by respiratory inductive plethysmography, and HRV, collected by polar precision performance. The CPG presented lower values of percent rib cage inspiratory and expiratory contributions to tidal volume (%RCi and %RCe) at discharge time, compared to CG. No statistical differences between groups were observed for HRV variables and both groups presented lower values of these indices, compared to preoperative ones. In this context, the patients who received CPAP throughout the whole rehabilitation program were discharged with a better BP, which could indicate more synchronized breathing. CPAP did not influence cardiac autonomic modulation in the long term.


Assuntos
Exercício Físico , Pressão Positiva Contínua nas Vias Aéreas , Respiração , Ponte de Artéria Coronária , Frequência Cardíaca
8.
Braz. j. med. biol. res ; 54(10): e10514, 2021. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1285648

RESUMO

Exercise intolerance is the hallmark consequence of advanced chronic heart failure (HF). The six-minute step test (6MST) has been considered an option for the six-minute walk test because it is safe, inexpensive, and can be applied in small places. However, its reliability and concurrent validity has still not been investigated in participants with HF with reduced ejection fraction (HFrEF). Clinically stable HFrEF participants were included. Reliability and error measurement were calculated by comparing the first with the second 6MST result. Forty-eight hours after participants underwent the 6MST, they were invited to perform a cardiopulmonary exercise test (CPET) on a cycle ergometer. Concurrent validity was assessed by correlation between number of steps and peak oxygen uptake (V̇O2 peak) at CPET. Twenty-seven participants with HFrEF (60±8 years old and left ventricle ejection fraction of 41±6%) undertook a mean of 94±30 steps in the 6MST. Intra-rater reliability was excellent for 6MST (ICC=0.9), with mean error of 4.85 steps and superior and inferior limits of agreement of 30.6 and -20.9 steps, respectively. In addition, strong correlations between number of steps and CPET workload (r=0.76, P<0.01) and peak V̇O2 (r=0.71, P<0.01) were observed. From simple linear regression the following predictive equations were obtained with 6MST results: V̇O2 peak (mL/min) = 350.22 + (7.333 × number of steps), with R2=0.51, and peak workload (W) = 4.044 + (0.772 × number of steps), with R2=0.58. The 6MST was a reliable and valid tool to assess functional capacity in HFrEF participants and may moderately predict peak workload and oxygen uptake of a CPET.


Assuntos
Humanos , Pessoa de Meia-Idade , Idoso , Teste de Esforço , Insuficiência Cardíaca/diagnóstico , Consumo de Oxigênio , Volume Sistólico , Reprodutibilidade dos Testes , Tolerância ao Exercício , Teste de Caminhada
9.
Braz. j. med. biol. res ; 54(2): e10084, 2021. tab, graf
Artigo em Inglês | LILACS, Coleciona SUS | ID: biblio-1142577

RESUMO

The objective of this study was to investigate the impact of chronic obstructive pulmonary disease (COPD)-heart failure (HF) coexistence on linear and nonlinear dynamics of heart rate variability (HRV). Forty-one patients (14 with COPD-HF and 27 HF) were enrolled and underwent pulmonary function and echocardiography evaluation to confirm the clinical diagnosis. Heart rate (HR) and R-R intervals (iRR) were collected during active postural maneuver (APM) [supine (10 min) to orthostasis (10 min)], respiratory sinus arrhythmia maneuver (RSA-M) (4 min), and analysis of frequency domain, time domain, and nonlinear HRV. We found expected autonomic response during orthostatic changes with reduction of mean iRR, root mean square of successive differences between heart beats (RMSSD), RR tri index, and high-frequency [HF (nu)] and an increased mean HR, low-frequency [LF (nu)], and LF/HF (nu) compared with supine only in HF patients (P<0.05). Patients with COPD-HF coexistence did not respond to postural change. In addition, in the orthostatic position, higher HF nu and lower LF nu and LF/HF (nu) were observed in COPD-HF compared with HF patients. HF patients showed an opposite response during RSA-M, with increased sympathetic modulation (LF nu) and reduced parasympathetic modulation (HF nu) (P<0.05) compared with COPD-HF patients. COPD-HF directly influenced cardiac autonomic modulation during active postural change and controlled breathing, demonstrating an autonomic imbalance during sympathetic and parasympathetic maneuvers compared with isolated HF.


Assuntos
Humanos , Masculino , Feminino , Pessoa de Meia-Idade , Idoso , Doença Pulmonar Obstrutiva Crônica/complicações , Insuficiência Cardíaca/complicações , Frequência Cardíaca , Volume Sistólico , Função Ventricular Esquerda , Dinâmica não Linear
10.
Braz J Med Biol Res ; 54(2): e10084, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33263641

RESUMO

The objective of this study was to investigate the impact of chronic obstructive pulmonary disease (COPD)-heart failure (HF) coexistence on linear and nonlinear dynamics of heart rate variability (HRV). Forty-one patients (14 with COPD-HF and 27 HF) were enrolled and underwent pulmonary function and echocardiography evaluation to confirm the clinical diagnosis. Heart rate (HR) and R-R intervals (iRR) were collected during active postural maneuver (APM) [supine (10 min) to orthostasis (10 min)], respiratory sinus arrhythmia maneuver (RSA-M) (4 min), and analysis of frequency domain, time domain, and nonlinear HRV. We found expected autonomic response during orthostatic changes with reduction of mean iRR, root mean square of successive differences between heart beats (RMSSD), RR tri index, and high-frequency [HF (nu)] and an increased mean HR, low-frequency [LF (nu)], and LF/HF (nu) compared with supine only in HF patients (P<0.05). Patients with COPD-HF coexistence did not respond to postural change. In addition, in the orthostatic position, higher HF nu and lower LF nu and LF/HF (nu) were observed in COPD-HF compared with HF patients. HF patients showed an opposite response during RSA-M, with increased sympathetic modulation (LF nu) and reduced parasympathetic modulation (HF nu) (P<0.05) compared with COPD-HF patients. COPD-HF directly influenced cardiac autonomic modulation during active postural change and controlled breathing, demonstrating an autonomic imbalance during sympathetic and parasympathetic maneuvers compared with isolated HF.


Assuntos
Insuficiência Cardíaca/complicações , Frequência Cardíaca , Doença Pulmonar Obstrutiva Crônica/complicações , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Dinâmica não Linear , Volume Sistólico , Função Ventricular Esquerda
11.
World J Microbiol Biotechnol ; 36(11): 171, 2020 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-33067644

RESUMO

Aureobasidium strains isolated from diverse unconventional environments belonging to the species A. pullulans, A. melanogenum, and A. subglaciale were evaluated for Volatile Organic Compounds (VOCs) production as a part of their modes of action against Botrytis cinerea of tomato and table grape. By in vitro assay, VOCs generated by the antagonists belonging to the species A. subglaciale showed the highest inhibition percentage of the pathogen mycelial growth (65.4%). In vivo tests were conducted with tomatoes and grapes artificially inoculated with B. cinerea conidial suspension, and exposed to VOCs emitted by the most efficient antagonists of each species (AP1, AM10, AS14) showing that VOCs of AP1 (A. pullulans) reduced the incidence by 67%, partially confirmed by the in vitro results. Conversely, on table grape, VOCs produced by all the strains did not control the fungal incidence but were only reducing the infection severity (< 44.4% by A. pullulans; < 30.5% by A. melanogenum, and A. subglaciale). Solid-phase microextraction (SPME) and subsequent gas chromatography coupled to mass spectrometry identified ethanol, 3-methyl-1-butanol, 2-methyl-1-propanol as the most produced VOCs. However, there were differences in the amounts of produced VOCs as well as in their repertoire. The EC50 values of VOCs for reduction of mycelial growth of B. cinerea uncovered 3-methyl-1-butanol as the most effective compound. The study demonstrated that the production and the efficacy of VOCs by Aureobasidium could be directly related to the specific species and pathosystem and uncovers new possibilities for searching more efficient VOCs producing strains in unconventional habitats other than plants.


Assuntos
Aureobasidium/química , Botrytis/efeitos dos fármacos , Solanum lycopersicum/crescimento & desenvolvimento , Vitis/crescimento & desenvolvimento , Compostos Orgânicos Voláteis/farmacologia , Butanóis/isolamento & purificação , Butanóis/farmacologia , Cromatografia Gasosa-Espectrometria de Massas , Solanum lycopersicum/microbiologia , Testes de Sensibilidade Microbiana , Micélio/efeitos dos fármacos , Pentanóis/isolamento & purificação , Pentanóis/farmacologia , Doenças das Plantas/microbiologia , Doenças das Plantas/prevenção & controle , Microextração em Fase Sólida , Vitis/microbiologia , Compostos Orgânicos Voláteis/isolamento & purificação
12.
Heart Fail Rev ; 25(3): 549, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-31713084

RESUMO

The scholarship support information in Acknowledgement was missing.

14.
Breast ; 45: 56-60, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30877870

RESUMO

BACKGROUND: Breast angiosarcoma is a malignant mesenchymal neoplasm, which accounts for approximately 2% of all soft tissue sarcomas. Secondary breast angiosarcoma (SBA) may be related to chronic lymphedema after a mastectomy with lymph node dissection (Stewart Treves syndrome) and previous radiotherapy for complications from breast radiation treatment. It is a very rare condition; therefore, diagnosis and management are still a challenge. METHODS: The ANISC collected SBA data by means of a survey sent to all Italian breast centres in the ANISC. The clinicopathological characteristics and the management of this disease were analysed. RESULTS: Twenty-four centres participated in this survey in which 112 cases of SBA were analysed. The median age of the women with SBA was 68.9 years and it appeared approximately 90 months after the first irradiation for breast cancer. In 92% of cases, a mastectomy was performed without axillary dissection for those patients having a high grade of SBA (74.2%). The prognosis was worse in the high-grade cases (overall survival-OS: 36 months) as compared with the low-grade cases (OS: 48 months). After a follow-up of 5 years, 50.5% of the patients were still alive. Disease-free survival (DFS) was 35 months, and there were no differences between the groups of patients with either high- or low-grade histology. CONCLUSIONS: Secondary breast angiosarcoma is a very aggressive disease associated with a short survival outcome. The surgical approach still remains an important step in the course of treatment; furthermore, an accurate histological examination is helpful in establishing the prognosis of the patient. A mastectomy is mandatory. A longer OS was observed in patients with low-grade angiosarcoma as compared to high-grade angiosarcoma (C.I. 40-57 vs. 31-41 months).


Assuntos
Neoplasias da Mama/mortalidade , Hemangiossarcoma/mortalidade , Segunda Neoplasia Primária/mortalidade , Complicações Pós-Operatórias/mortalidade , Idoso , Neoplasias da Mama/etiologia , Neoplasias da Mama/patologia , Neoplasias da Mama/cirurgia , Feminino , Hemangiossarcoma/complicações , Hemangiossarcoma/etiologia , Hemangiossarcoma/cirurgia , Humanos , Itália/epidemiologia , Excisão de Linfonodo/efeitos adversos , Linfangiossarcoma/complicações , Mastectomia/mortalidade , Segunda Neoplasia Primária/etiologia , Segunda Neoplasia Primária/cirurgia , Complicações Pós-Operatórias/etiologia , Prognóstico , Estudos Retrospectivos , Cirurgiões/estatística & dados numéricos , Inquéritos e Questionários
15.
Heart Fail Rev ; 24(1): 69-80, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-29995216

RESUMO

Endothelial dysfunction plays as an important role on mismatch responses that occur during exercise in patients with congestive heart failure (CHF). However, cardiac rehabilitation, a core component of management of CHF patients, can improve endothelial function, contributing to reduce the morbidity and mortality of these patients. The primary aims of this review were to describe the importance of flow-mediated dilatation (FMD) as a non-invasive validation tool to assess endothelial dysfunction and to highlight the relevance of scientific studies that evaluated the effects of exercise interventions on peripheral vascular endothelial function as measured by FMD in patients with CHF with both preserved and reduced ejection fraction.


Assuntos
Terapia por Exercício , Exercício Físico , Insuficiência Cardíaca/reabilitação , Vasodilatação , Artéria Braquial , Terapia de Ressincronização Cardíaca , Endotélio Vascular/fisiopatologia , Humanos , Volume Sistólico , Resultado do Tratamento , Disfunção Ventricular Esquerda/fisiopatologia
16.
Braz J Med Biol Res ; 51(11): e7837, 2018 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-30328936

RESUMO

The objective of this study was to assess cardiovascular, respiratory, and metabolic responses during a commonly used dynamic leg press resistance exercise until exhaustion (TEx) at different intensities and compare with critical load (CL). This was a prospective, cross-sectional, controlled, and crossover study. Twelve healthy young men (23±2.5 years old) participated. The subjects carried out three bouts of resistance exercise in different percentages of 1 repetition maximum (60, 75, and 90% 1RM) until TEx. CL was obtained by means of hyperbolic model and linearization of the load-duration function. During all bout intensities, oxygen uptake (VO2), carbon dioxide production (VCO2), ventilation (VE), and respiratory exchange ratio (RER) were obtained. Variations (peak-rest=Δ) were corrected by TEx. In addition, systolic and diastolic blood pressure (SBP and DBP), blood lactate concentration [La-] and Borg scores were obtained at the peak and corrected to TEx. CL induced greater TEx as well as number of repetitions when compared to all intensities (P<0.001). During CL, Borg/TEx, ΔSBP/TEx, ΔDBP/TEx, and [La-] were significantly lower compared with 90% load (P<0.0001). In addition, VO2, VCO2, VE, and RER were higher during CL when compared to 90 or 75%. TEx was significantly correlated with VO2 on CL (r=0.73, P<0.05). These findings support the theory that CL constitutes the intensity that can be maintained for a very long time, provoking greater metabolic and ventilatory demand and lower cardiovascular and fatigue symptoms during resistance exercise.


Assuntos
Teste de Esforço/métodos , Fadiga/fisiopatologia , Frequência Cardíaca/fisiologia , Consumo de Oxigênio/fisiologia , Troca Gasosa Pulmonar/fisiologia , Treinamento Resistido , Adulto , Estudos Cross-Over , Estudos Transversais , Humanos , Masculino , Estudos Prospectivos , Fatores de Tempo
17.
Nat Commun ; 9(1): 2305, 2018 06 13.
Artigo em Inglês | MEDLINE | ID: mdl-29899336

RESUMO

Strong many-body interactions in solids yield a host of fascinating and potentially useful physical properties. Here, from angle-resolved photoemission experiments and ab initio many-body calculations, we demonstrate how a strong coupling of conduction electrons with collective plasmon excitations of their own Fermi sea leads to the formation of plasmonic polarons in the doped ferromagnetic semiconductor EuO. We observe how these exhibit a significant tunability with charge carrier doping, leading to a polaronic liquid that is qualitatively distinct from its more conventional lattice-dominated analogue. Our study thus suggests powerful opportunities for tailoring quantum many-body interactions in solids via dilute charge carrier doping.

18.
Braz J Med Biol Res ; 51(6): e6962, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29791599

RESUMO

Despite the appeal of ultra-short-term heart rate variability (HRV) methods of analysis applied in the clinical and research settings, the number of studies that have investigated HRV by analyzing R-R interval (RRi) recordings shorter than 5 min is still limited. Moreover, ultra-short-term HRV analysis has not been extensively validated during exercise and, currently, no indications exist for its applicability during resistance exercise. The aim of the present study was to compare ultra-short-term HRV analysis with standard short-term HRV analysis during low-intensity, dynamic, lower limb resistance exercise in healthy elderly subjects. Heart rate (HR) and RRi signals were collected from 9 healthy elderly men during discontinuous incremental resistance exercise consisting of 4-min intervals at low intensities (10, 20, 30, and 35% of 1-repetition maximum). The original RRi signals were segmented into 1-, 2-, and 3-min sections. HRV was analyzed in the time domain (root mean square of the of differences between adjacent RRi, divided by the number of RRi, minus one [RMSSD]), RRi mean value and standard deviation [SDNN] (percentage of differences between adjacent NN intervals that are greater than 50 ms [pNN50]), and by non-linear analysis (short-term RRi standard deviation [SD1] and long-term RRi standard deviation [SD2]). No significant difference was found at any exercise intensity between the results of ultra-short-term HRV analysis and the results of standard short-term HRV analysis. Furthermore, we observed excellent (0.70 to 0.89) to near-perfect (0.90 to 1.00) concordance between linear and non-linear parameters calculated over 1- and 2-min signal sections and parameters calculated over 3-min signal sections. Ultra-short-term HRV analysis appears to be a reliable surrogate of standard short-term HRV analysis during resistance exercise in healthy elderly subjects.


Assuntos
Frequência Cardíaca/fisiologia , Treinamento Resistido/métodos , Idoso , Eletrocardiografia , Humanos , Masculino , Valores de Referência , Fatores de Tempo
19.
Eur J Surg Oncol ; 44(8): 1157-1163, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29653781

RESUMO

The Italian Society of Surgical Oncology (SICO) Breast Oncoteam developed a survey to explore the state of the art of neoadjuvant treatment for breast cancer in Italy, specifically focusing on cases treated during the two-year period 2014-2015. A questionnaire was sent to Italian Breast Units with a minimum of 150 new breast cancer cases treated/year according to the Senonetwork directory and to the SICO Breast Oncoteam Breast Unit network. A total of 23/107 Breast Units submitted the survey, reporting a total amount of 20156 cases of breast carcinoma (17241 invasive, 2915 in situ) treated in the biennium, corresponding approximately to 20% of newly diagnosed breast cancers in Italy. In the United States, medical treatment before surgery for breast cancer is indicated in about 22.7% of newly diagnosed cases according to the National Cancer Database, while a German study reported approximately 20% of cases treated with neoadjuvant therapy. In our survey, a total of 1673/17241 cases (9.7%) were treated with neoadjuvant therapy, ranging from 2.9% to 23.6% according to different centres, showing heterogeneity in neoadjuvant treatment indications, even in multidisciplinary breast units. Better resources should be engaged to achieve a standardised quality indicator for neoadjuvant treatment, and this indicator could be included among the European Society of Breast Cancer Specialists (EUSOMA) quality indicators. In the near future, we plan to develop a second survey to better test improvements in the employment of neoadjuvant therapy after the expiry of the 2016 European Parliament deadline and after the 2017 St. Gallen Conference recommendations.


Assuntos
Neoplasias da Mama/terapia , Mama/patologia , Estadiamento de Neoplasias , Sociedades Médicas , Oncologia Cirúrgica , Neoplasias da Mama/diagnóstico , Neoplasias da Mama/epidemiologia , Bases de Dados Factuais , Feminino , Seguimentos , Humanos , Itália/epidemiologia , Morbidade/tendências , Terapia Neoadjuvante/métodos , Prognóstico , Estudos Retrospectivos , Fatores de Tempo
20.
Braz. j. med. biol. res ; 51(11): e7837, 2018. tab, graf
Artigo em Inglês | LILACS | ID: biblio-974248

RESUMO

The objective of this study was to assess cardiovascular, respiratory, and metabolic responses during a commonly used dynamic leg press resistance exercise until exhaustion (TEx) at different intensities and compare with critical load (CL). This was a prospective, cross-sectional, controlled, and crossover study. Twelve healthy young men (23±2.5 years old) participated. The subjects carried out three bouts of resistance exercise in different percentages of 1 repetition maximum (60, 75, and 90% 1RM) until TEx. CL was obtained by means of hyperbolic model and linearization of the load-duration function. During all bout intensities, oxygen uptake (VO2), carbon dioxide production (VCO2), ventilation (VE), and respiratory exchange ratio (RER) were obtained. Variations (peak-rest=Δ) were corrected by TEx. In addition, systolic and diastolic blood pressure (SBP and DBP), blood lactate concentration [La-] and Borg scores were obtained at the peak and corrected to TEx. CL induced greater TEx as well as number of repetitions when compared to all intensities (P<0.001). During CL, Borg/TEx, ΔSBP/TEx, ΔDBP/TEx, and [La-] were significantly lower compared with 90% load (P<0.0001). In addition, VO2, VCO2, VE, and RER were higher during CL when compared to 90 or 75%. TEx was significantly correlated with VO2 on CL (r=0.73, P<0.05). These findings support the theory that CL constitutes the intensity that can be maintained for a very long time, provoking greater metabolic and ventilatory demand and lower cardiovascular and fatigue symptoms during resistance exercise.


Assuntos
Humanos , Masculino , Adulto , Consumo de Oxigênio/fisiologia , Troca Gasosa Pulmonar/fisiologia , Teste de Esforço/métodos , Treinamento Resistido , Fadiga/fisiopatologia , Frequência Cardíaca/fisiologia , Fatores de Tempo , Estudos Transversais , Estudos Prospectivos , Estudos Cross-Over
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