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Globally, cancer is the second leading cause of death, with numbers greatly exceeding those for human immunodeficiency virus/acquired immunodeficiency syndrome, tuberculosis, and malaria combined. Limited access to timely diagnosis, to affordable, effective treatment, and to high-quality care are just some of the factors that lead to disparities in cancer survival between countries and within countries. In this article, the authors consider various factors that prevent access to cancer medicines (particularly access to essential cancer medicines). Even if an essential cancer medicine is included on a national medicines list, cost might preclude its use, it might be prescribed or used inappropriately, weak infrastructure might prevent it being accessed by those who could benefit, or quality might not be guaranteed. Potential strategies to address the access problems are discussed, including universal health coverage for essential cancer medicines, fairer methods for pricing cancer medicines, reducing development costs, optimizing regulation, and improving reliability in the global supply chain. Optimizing schedules for cancer therapy could reduce not only costs, but also adverse events, and improve access. More and better biomarkers are required to target patients who are most likely to benefit from cancer medicines. The optimum use of cancer medicines depends on the effective delivery of several services allied to oncology (including laboratory, imaging, surgery, and radiotherapy). Investment is necessary in all aspects of cancer care, from these supportive services to technologies, and the training of health care workers and other staff.
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Acessibilidade aos Serviços de Saúde/tendências , Neoplasias/terapia , Qualidade da Assistência à Saúde , Terapia Combinada/tendências , HumanosRESUMO
BACKGROUND: Three-vessel disease (3VD) is a cardiovascular disorder that affects the three main coronary arteries. Gated myocardial perfusion SPECT (GMPS) evaluates ventricular function, synchrony, and myocardial perfusion. However, the diagnostic performance of GMPS parameters to assess 3VD has not been fully explored. AIMS: To assess the univariate performance capacity of GMPS parameters, and to evaluate whether phase parameters could provide additional predictive value for the detection of patients with 3VD compared to control subjects. METHODS: We designed paired retrospective samples of GMPS images of patients with 3VD (stenosis > 70% of left anterior descending, right coronary, and circumflex coronary arteries) and without 3VD. A GMPS in rest-stress protocol was performed using 99mTc-Sestamibi and thallium and analyzed with the 3D method. Area under the receiver-operating characteristic curves (AUROC), decision curve analyses and diagnostic test performance were obtained for univariable analyses and stepwise binomial logistic regression for multivariable performance. RESULTS: 474 Patients were included: 237 with 3VD (84% males, mean age 61.7 ± 9.9 years) and 237 with normal GMPS (51% women, mean age 63.8 ± 10.6 years). The highest AUROC for perfusion parameters were recorded for SSS, SRS and TID. For dyssynchrony parameters, both entropy and bandwidth in rest and stress phases displayed the highest AUROC and diagnostic capacity to detect 3VD. A multivariate model with SRS ≥ 4, SDS ≥ 2, TID > 1.19 and sBW ≥ 48° displayed the highest diagnostic capacity (0.923 [95% CI 0.897-0.923]) to detect 3VD. CONCLUSION: Perfusion and dyssynchrony were the parameters which were most able to discriminate patients with 3VD from those who did not have CAD.
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Doença da Artéria Coronariana , Imagem de Perfusão do Miocárdio , Doenças Vasculares , Disfunção Ventricular Esquerda , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Transversais , México , Imagem de Perfusão do Miocárdio/métodos , Estudos Retrospectivos , Tomografia Computadorizada de Emissão de Fóton Único/métodos , PerfusãoRESUMO
Atrial fibrillation (AF) is the most common cardiac arrhythmia. However, the relation between congenital heart defects and the predisposition to AF is not fully understood. A 65-year-old male was admitted into the emergency department due to progressive dyspnea, orthopnea, palpitations, and edema. Transthoracic echocardiogram showed bi-atrial enlargement and dysplasia of the mitral leaflets with severe mitral regurgitation. Also, a membrane was noted in the LA, dividing the chamber into two parts, suggestive of cor triatriatum sinister. Coronary computed tomography angiography demonstrated a soft tissue septum in the left atrium. Multimodal evaluation is of vital importance for a complete approach, since, detected in time, it has an excellent prognosis.
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Fibrilação Atrial , Cardiopatias Congênitas , Idoso , Humanos , Masculino , Fibrilação Atrial/complicações , Fibrilação Atrial/diagnóstico por imagem , Coração Triatriado/complicações , Coração Triatriado/diagnóstico por imagem , Ecocardiografia , Átrios do CoraçãoRESUMO
Induction machines (IMs) play a critical role in various industrial processes but are susceptible to degenerative failures, such as broken rotor bars. Effective diagnostic techniques are essential in addressing these issues. In this study, we propose the utilization of convolutional neural networks (CNNs) for detection of broken rotor bars. To accomplish this, we generated a dataset comprising current samples versus angular position using finite element method magnetics (FEMM) software for a squirrel-cage rotor with 28 bars, including scenarios with 0 to 6 broken bars at every possible relative position. The dataset consists of a total of 16,050 samples per motor. We evaluated the performance of six different CNN architectures, namely Inception V4, NasNETMobile, ResNET152, SeNET154, VGG16, and VGG19. Our automatic classification system demonstrated an impressive 99% accuracy in detecting broken rotor bars, with VGG19 performing exceptionally well. Specifically, VGG19 exhibited high accuracy, precision, recall, and F1-Score, with values approaching 0.994 and 0.998. Notably, VGG19 exhibited crucial activations in its feature maps, particularly after domain-specific training, highlighting its effectiveness in fault detection. Comparing CNN architectures assists in selecting the most suitable one for this application based on processing time, effectiveness, and training losses. This research suggests that deep learning can detect broken bars in induction machines with accuracy comparable to that of traditional methods by analyzing current signals using CNNs.
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PURPOSE: In the literature, we find that patients with lacertus syndrome (LS), proximal median nerve compression at the elbow, present subjective improvement of thumb, and index flexion strength after lacertus fibrosus (LF) release. The aim of this study is to objectively evaluate the immediate change in intraoperative flexion strength after LF release. METHOD: We retrospectively reviewed prospectively collected data of a cohort of 24 patients with a double crush syndrome of the median nerve with no response to conservative treatment. All patients had surgery with LF and carpal tunnel release (CTR) under wide-awake local anaesthesia and no tourniquet (WALANT) and were evaluated intraoperatively with a dynamometer immediately before and after LF release. Flexor digitorum profundus of the second finger (FDP2) and Flexor pollicis longus (FPL) were tested in peak strength to failure. The primary outcome was the percentage of change in strength before and after the release in both assessed muscles. CTR was done after evaluating the change in flexor strength. RESULTS: A percentage of 79.2 women with an average age of 43.3 years. The average strength of FDP2 before LF release was 15.5 pounds (lbs.) (7.0 kg) (SD, 7.2 lbs (3.3 kg)) and 27.1 lbs. (12.2 kg) (SD, 7.1 lbs. (3.2 kg)) after LF release, which corresponds to a 96% (SD, 70%) change in strength (p=0.000). For FPL, the average pre-release strength was 17.7 lbs. (8.0kg) (SD, 4.8 lbs. (2.2 kg)) and 27.4 lbs. (12.4 kg) (SD, 5.2 lbs. (2.4 kg)) post-release, this corresponded to a 65% (SD, 38%) change in strength (p=0.000). CONCLUSIONS: Peak strength to failure in FDP2 and FPL has an immediate significant recovery after LF surgical release in patients with Lacertus syndrome. LEVEL OF EVIDENCE: IV, retrospective study.
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Síndrome do Túnel Carpal , Articulação do Cotovelo , Humanos , Feminino , Adulto , Cotovelo , Estudos Retrospectivos , Nervo Mediano , Tendões , Articulação do Cotovelo/cirurgia , Síndrome do Túnel Carpal/cirurgiaRESUMO
Disruptions of the light/dark cycle and unhealthy diets can promote misalignment of biological rhythms and metabolic alterations, ultimately leading to an oxidative stress condition. Grape seed proanthocyanidin extract (GSPE), which possesses antioxidant properties, has demonstrated its beneficial effects in metabolic-associated diseases and its potential role in modulating circadian disruptions. Therefore, this study aimed to assess the impact of GSPE administration on the liver oxidant system of healthy and diet-induced obese rats undergoing a sudden photoperiod shift. To this end, forty-eight photoperiod-sensitive Fischer 344/IcoCrl rats were fed either a standard (STD) or a cafeteria diet (CAF) for 6 weeks. A week before euthanizing, rats were abruptly transferred from a standard photoperiod of 12 h of light/day (L12) to either a short (6 h light/day, L6) or a long photoperiod (18 h light/day, L18) while receiving a daily oral dose of vehicle (VH) or GSPE (25 mg/kg). Alterations in body weight gain, serum and liver biochemical parameters, antioxidant gene and protein expression, and antioxidant metabolites were observed. Interestingly, GSPE partially ameliorated these effects by reducing the oxidative stress status in L6 through an increase in GPx1 expression and in hepatic antioxidant metabolites and in L18 by increasing the NRF2/KEAP1/ARE pathway, thereby showing potential in the treatment of circadian-related disorders by increasing the hepatic antioxidant response in a photoperiod-dependent manner.
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Extrato de Sementes de Uva , Proantocianidinas , Ratos , Animais , Antioxidantes/metabolismo , Proteína 1 Associada a ECH Semelhante a Kelch/metabolismo , Fotoperíodo , Ratos Wistar , Fator 2 Relacionado a NF-E2/metabolismo , Extrato de Sementes de Uva/farmacologia , Extrato de Sementes de Uva/uso terapêutico , Proantocianidinas/metabolismo , Obesidade/tratamento farmacológico , Obesidade/etiologia , Obesidade/metabolismo , Fígado/metabolismoRESUMO
Cardiovascular diseases are the most common cause of mortality in the world. Currently, type 2 diabetes mellitus (T2DM) is one of the main risk factors for major adverse cardiovascular events. T2DM patients have a four-fold higher risk of developing heart failure and 10 to 12 times higher mortality. Echocardiography in all its modalities is the best clinical tool for heart failure diagnosis, since it provides static and dynamic images of the heart that allow to identify structural and functional changes, such as pressure variations, flow changes, left ventricular ejection fraction and myocardial surfaces anatomical remodeling.
Las enfermedades cardiovasculares constituyen la causa más común de mortalidad en el mundo. Actualmente, la diabetes mellitus tipo 2 (DM2) representa uno de los principales factores de riesgo de eventos adversos cardiovasculares mayores. Los pacientes que las padecen tienen un riesgo cuatro veces mayor de desarrollar insuficiencia cardíaca y una mortalidad de 10 a 12 veces mayor. La ecocardiografía en todas sus modalidades es la mejor herramienta clínica para el diagnóstico de la insuficiencia cardíaca, ya que proporciona imágenes estáticas y dinámicas del corazón que permiten identificar cambios estructurales y funcionales, como alteraciones en las presiones, cambios de flujo, fracción de expulsión del ventrículo izquierdo y remodelación anatómica de las superficies miocárdicas.
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Diabetes Mellitus Tipo 2 , Insuficiência Cardíaca , Humanos , Diabetes Mellitus Tipo 2/complicações , Volume Sistólico , Função Ventricular Esquerda , Fatores de Risco , Insuficiência Cardíaca/diagnóstico , Insuficiência Cardíaca/etiologiaRESUMO
OBJECTIVES: Lupus nephritis (LN) is a severe complication of systemic lupus erythematosus (SLE). Unfortunately, 10-20% of patients with LN develop end-stage renal disease (ESRD), and renal transplantation may be a therapeutic option. However, concerns about LN recurrence after transplant have been reported. We aimed to assess long-term post-transplant graft and patient survival in LN compared to patients with non-autoimmune nephropathy (polycystic kidney disease - PCKD). METHODS: We carried out a single-centre retrospective study of all patients who underwent renal transplantation due to LN in a referral unit between 1980 and 2018. This cohort was compared with a group of PCKD patients. The main outcome variables were graft and patient survival for up to 20 years, and the time-course of serum creatinine and proteinuria in the first 5 years after transplantation. Cumulative survival rates were estimated by the Kaplan-Meier method and compared using the log-rank test. RESULTS: We included 53 patients: LN group (n=21) and PCKD group (n=32). Baseline clinical characteristics were similar in both groups, except age at transplantation (39.8±11.3 years in the LN group and 46.6±5.0 years in the PCKD group; p=0.004). No significant differences were found regarding graft (p=0.59) or patient survival (p=0.087) at 20 years of follow-up. CONCLUSIONS: Despite concerns about LN recurrence after renal transplantation, this study shows that this procedure might be a safe alternative therapy for ESRD related to SLE and may provide long-term survival.
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Falência Renal Crônica , Transplante de Rim , Lúpus Eritematoso Sistêmico , Nefrite Lúpica , Humanos , Falência Renal Crônica/etiologia , Falência Renal Crônica/cirurgia , Transplante de Rim/efeitos adversos , Lúpus Eritematoso Sistêmico/complicações , Nefrite Lúpica/complicações , Nefrite Lúpica/tratamento farmacológico , Nefrite Lúpica/cirurgia , Estudos Retrospectivos , Resultado do Tratamento , UniversidadesRESUMO
Induction machines (IMs) are a critical component of many industrial processes, and their failure can cause large economic losses. Condition-based maintenance systems (CBMs) that are capable of detecting their failures at an incipient stage can reduce these risks by continuously monitoring the IMs' condition. The development and reliable operations of CBMs systems require rapid modeling of the faulty IM. Due to the fault-induced IM asymmetries, these models are much more complex than those used for a healthy IM. In particular, a mixed eccentricity fault (static and dynamic), which can degenerate into rubbing and destruction of the rotor, produces a non-uniform IM air gap that is different for each rotor position, which makes its very difficult to calculate the IM's inductance matrix. In this work, a new analytical model of an eccentric IM is presented. It is based on the winding tensor approach, which allows a clear separation between the air gap and winding-related faults. Contrary to previous approaches, where complex expressions have been developed for obtaining mutual inductances between conductors and windings of an eccentric IM, a conformal transformation is proposed in this work, which allows using the simple inductance expressions of a healthy IM. This novel conformal winding tensor approach (CWFA) is theoretically explained and validated with the diagnosis of two commercial IMs with a mixed eccentricity fault.
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Algoritmos , Indústrias , Simulação por Computador , Conformação MolecularRESUMO
BACKGROUND: Immunoglobulin G4-related disease (IgG4-RD) is a recently recognized fibro-inflammatory pathology that has been reported to affect principally the retroperitoneum, hepatobiliary system, salivary glands, orbital structures or lymph nodes. However, IgG4-RD with laryngeal involvement is a very rare entity. Our aims were to describe a case of subglottic stenosis as first and only manifestation of IgG4-RD and review the literature. A patient with IgG4-RD affecting the larynx that presented as subglottic stenosis is described. A MEDLINE database search of IgG4-RD cases with laryngopharyngeal manifestations was also conducted. A 30-year-old Caucasian woman was referred to a tertiary care hospital for dyspnea on exertion, which had been increasing for the last 4 months. Medical and surgical procedures revealed a subglottic stenosis, with a histological finding of IgG4 positive plasma cell infiltration. There was no evidence of other organ involvement. She was successfully treated with oral glucocorticoids and rituximab infusions. Glucocorticoids were rapidly tapered and the rituximab regimen was optimized, with no evidence of relapses. In the literature review, we found a total of 12 reported cases with laryngopharyngeal involvement, two of them with subglottic stenosis. IgG4-RD of the larynx is rare but should be considered after excluding more common disorders.
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Doença Relacionada a Imunoglobulina G4/diagnóstico , Doenças da Laringe/diagnóstico , Adulto , Idoso , Constrição Patológica/etiologia , Feminino , Humanos , Doença Relacionada a Imunoglobulina G4/tratamento farmacológico , Doença Relacionada a Imunoglobulina G4/patologia , Fatores Imunológicos/administração & dosagem , Doenças da Laringe/tratamento farmacológico , Doenças da Laringe/patologia , Masculino , Pessoa de Meia-Idade , Rituximab/administração & dosagemRESUMO
Acute inflammation is a key component of the immune system's response to pathogens, toxic agents, or tissue injury, involving the stimulation of defense mechanisms aimed to removing pathogenic factors and restoring tissue homeostasis. However, uncontrolled acute inflammatory response may lead to chronic inflammation, which is involved in the development of many diseases, including cancer. Nowadays, the need to find new potential therapeutic compounds has raised the worldwide scientific interest to study the marine environment. Specifically, microalgae are considered rich sources of bioactive molecules, such as carotenoids, which are natural isoprenoid pigments with important beneficial effects for health due to their biological activities. Carotenoids are essential nutrients for mammals, but they are unable to synthesize them; instead, a dietary intake of these compounds is required. Carotenoids are classified as carotenes (hydrocarbon carotenoids), such as α- and ß-carotene, and xanthophylls (oxygenate derivatives) including zeaxanthin, astaxanthin, fucoxanthin, lutein, α- and ß-cryptoxanthin, and canthaxanthin. This review summarizes the present up-to-date knowledge of the anti-inflammatory and anticancer activities of microalgal carotenoids both in vitro and in vivo, as well as the latest status of human studies for their potential use in prevention and treatment of inflammatory diseases and cancer.
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Anti-Inflamatórios/química , Antineoplásicos/química , Carotenoides/química , Microalgas , Animais , Organismos AquáticosRESUMO
Over the years, induction machines (IMs) have become key components in industry applications as mechanical power sources (working as motors) as well as electrical power sources (working as generators). Unexpected breakdowns in these components can lead to unscheduled down time and consequently to large economic losses. As breakdown of IMs for failure study is not economically feasible, several IM computer models under faulty conditions have been developed to investigate the characteristics of faulty machines and have allowed reducing the number of destructive tests. This paper provides a review of the available techniques for faulty IMs modelling. These models can be categorised as models based on electrical circuits, on magnetic circuits, models based on numerical methods and the recently proposed in the technical literature hybrid models or models based on finite element method (FEM) analytical techniques. A general description of each type of model is given with its main benefits and drawbacks in terms of accuracy, running times and ability to reproduce a given fault.
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Since it is not efficient to physically study many machine failures, models of faulty induction machines (IMs) have attracted a rising interest. These models must be accurate enough to include fault effects and must be computed with relatively low resources to reproduce different fault scenarios. Moreover, they should run in real time to develop online condition-monitoring (CM) systems. Hybrid finite element method (FEM)-analytical models have been recently proposed for fault diagnosis purposes since they keep good accuracy, which is widely accepted, and they can run in real-time simulators. However, these models still require the full simulation of the FEM model to compute the parameters of the analytical model for each faulty scenario with its corresponding computing needs. To address these drawbacks (large computing power and memory resources requirements) this paper proposes sparse identification techniques in combination with the trigonometric interpolation polynomial for the computation of IM model parameters. The proposed model keeps accuracy similar to a FEM model at a much lower computational effort, which could contribute to the development and to the testing of condition-monitoring systems. This approach has been applied to develop an IM model under static eccentricity conditions, but this may extend to other fault types.
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Induction machines (IMs) are one of the main sources of mechanical power in many industrial processes, especially squirrel cage IMs (SCIMs), due to their robustness and reliability. Their sudden stoppage due to undetected faults may cause costly production breakdowns. One of the most frequent types of faults are cage faults (bar and end ring segment breakages), especially in motors that directly drive high-inertia loads (such as fans), in motors with frequent starts and stops, and in case of poorly manufactured cage windings. A continuous monitoring of IMs is needed to reduce this risk, integrated in plant-wide condition based maintenance (CBM) systems. Diverse diagnostic techniques have been proposed in the technical literature, either data-based, detecting fault-characteristic perturbations in the data collected from the IM, and model-based, observing the differences between the data collected from the actual IM and from its digital twin model. In both cases, fast and accurate IM models are needed to develop and optimize the fault diagnosis techniques. On the one hand, the finite elements approach can provide highly accurate models, but its computational cost and processing requirements are very high to be used in on-line fault diagnostic systems. On the other hand, analytical models can be much faster, but they can be very complex in case of highly asymmetrical machines, such as IMs with multiple cage faults. In this work, a new method is proposed for the analytical modelling of IMs with asymmetrical cage windings using a tensor based approach, which greatly reduces this complexity by applying routine tensor algebra to obtain the parameters of the faulty IM model from the healthy one. This winding tensor approach is explained theoretically and validated with the diagnosis of a commercial IM with multiple cage faults.
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Algoritmos , Indústrias , Simulação por Computador , Reprodutibilidade dos TestesRESUMO
The topical use of rosmarinic acid (RA) in skin inflammatory pathologies is restricted due to its poor water solubility, poor permeability, and chemical instability. In this study, RA-loaded transethosomes-in-Carbopol® formulations have been developed to evaluate its anti-inflammatory activity on imiquimod-induced psoriasis-like skin inflammation in mice. In vitro release profiles demonstrated sustained behavior due to the retentive action of gel and the entrapment of RA into the vesicles. However, the low viscosity of the combined formulation increased the drug release rate. Animal evaluation of anti-inflammatory activity demonstrated that transethosomes-in-gel containing dexamethasone (Dex-TE-Gel), as positive control, showed effect in all the pro-inflammatory parameters evaluated, evidencing that these drug-loaded nanocarriers have been effectively reached the site of action. In addition, transethosomes-in-gel containing RA (RA-TE-Gel) formulations produced a great reduction in the punch edema (P < 0.001) and in TNF-α and IL-6 (P < 0.05). However, non-significant differences were obtained for IL-1ß, IL17, and MPO. Despite the protecting effect of Carbopol® and transethosomes on oxidation index and antioxidant activity of RA over the 7 days of treatment, however, a degradation process of this antioxidant to caffeic acid may be the cause of these in vivo results. We have also checked that the pH existing into the intercellular space of damaged cells (pH 6.8) may be affecting. Therefore, our results suggest that RA-TE-Gel could act as an effective RA formulation for skin delivery; further studies will help to understand the loss of activity at the cellular level.
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Cinamatos/administração & dosagem , Cinamatos/uso terapêutico , Depsídeos/administração & dosagem , Depsídeos/uso terapêutico , Psoríase/tratamento farmacológico , Administração Cutânea , Animais , Dexametasona/administração & dosagem , Dexametasona/uso terapêutico , Portadores de Fármacos , Composição de Medicamentos , Sistemas de Liberação de Medicamentos , Liberação Controlada de Fármacos , Feminino , Géis , Camundongos , Camundongos Endogâmicos BALB C , Viscosidade , Ácido RosmarínicoRESUMO
PURPOSE: The study is aimed at assessing the acute effect of orange color and natural light exposure on cancer patients during chemotherapy sessions. Warmer environments and rooms receiving more sunlight hours were expected to impact vital signs, quality of life, and pain symptoms. METHODS: We used a single-group repeated-measures clinical trial design. For the purpose of the study, chemotherapy rooms were modified based on two experimental factors: color (white vs. orange) and sunlight orientation (south vs. north). On four consecutive sessions, cancer patients were randomly assigned to one of the following conditions: orange-north, orange-south, white-north, and white-south. They received chemotherapy per standard of care. The following outcomes were assessed: blood pressure, body temperature, heart rate, and European Quality of Life Five-Dimension Five-Level Scale Questionnaire (EUROQOL-5D-5L) including the visual analogue scale (EQ-VAS). RESULTS: Statistically significant beneficial effect of orange color room in self-rated health was found (p = 0.036, d = 0.28). Small differences in other parameters (body temperature, d = 0.34; diastolic blood pressure, d = 0.37; systolic blood pressure, d = 0.28) did not reach statistical significance. No differences were found based on room orientation. CONCLUSIONS: Compared with a cool-color design, a warm-color living environment could have a positive effect on patients' well-being during chemotherapy sessions. Although the clinical effect size on perceived health status and vital signs could be considered small, the cost-effectiveness analysis would support the use of the proposed configurations. More research is still needed. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT03873519.
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Neoplasias/terapia , Fototerapia/métodos , Idoso , Dor do Câncer/fisiopatologia , Dor do Câncer/terapia , Cor , Feminino , Nível de Saúde , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias/tratamento farmacológico , Medição da Dor/métodos , Qualidade de Vida , Inquéritos e Questionários , Sinais VitaisRESUMO
Gorgonian octocorals are considered a prolific source of secondary metabolites with a wide range of biological activities, including anti-inflammatory activity. In particular, the genus Briareum is known for producing a wealth of diterpenes with complex chemical structures. The chemical study of the methanolic extract of Briareum asbestinum collected in Bocas del Toro, on the Caribbean side of Panama, led to the isolation of three new eunicellin-type diterpenes: briarellin T (1), asbestinin 27 (2), asbestinin 28 (3) and the previously described asbestinin 17 (4). The structures of the new compounds were determined by extensive NMR analyses and HRMS. Anti-inflammatory activity assays showed a significant reduction of the pro-inflammatory cytokines TNF-α, IL-6, IL-1ß and IL-8 as well as a downregulation of COX-2 expression in LPS-stimulated THP-1 macrophages. These findings support the potential use of these marine compounds as therapeutic agents in the treatment of inflammatory diseases.
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Antozoários , Anti-Inflamatórios/farmacologia , Diterpenos/farmacologia , Animais , Ciclo-Oxigenase 2/metabolismo , PanamáRESUMO
Motor current signature analysis (MCSA) is a fault diagnosis method for induction machines (IMs) that has attracted wide industrial interest in recent years. It is based on the detection of the characteristic fault signatures that arise in the current spectrum of a faulty induction machine. Unfortunately, the MCSA method in its basic formulation can only be applied in steady state functioning. Nevertheless, every day increases the importance of inductions machines in applications such as wind generation, electric vehicles, or automated processes in which the machine works most of time under transient conditions. For these cases, new diagnostic methodologies have been proposed, based on the use of advanced time-frequency transforms-as, for example, the continuous wavelet transform, the Wigner Ville distribution, or the analytic function based on the Hilbert transform-which enables to track the fault components evolution along time. All these transforms have high computational costs and, furthermore, generate as results complex spectrograms, which require to be interpreted for qualified technical staff. This paper introduces a new methodology for the diagnosis of faults of IM working in transient conditions, which, unlike the methods developed up to today, analyzes the current signal in the slip-instantaneous frequency plane (s-IF), instead of the time-frequency (t-f) plane. It is shown that, in the s-IF plane, the fault components follow patterns that that are simple and unique for each type of fault, and thus does not depend on the way in which load and speed vary during the transient functioning; this characteristic makes the diagnostic task easier and more reliable. This work introduces a general scheme for the IMs diagnostic under transient conditions, through the analysis of the stator current in the s-IF plane. Another contribution of this paper is the introduction of the specific s-IF patterns associated with three different types of faults (rotor asymmetry fault, mixed eccentricity fault, and single-point bearing defects) that are theoretically justified and experimentally tested. As the calculation of the IF of the fault component is a key issue of the proposed diagnostic method, this paper also includes a comparative analysis of three different mathematical tools for calculating the IF, which are compared not only theoretically but also experimentally, comparing their performance when are applied to the tested diagnostic signals.
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Induction machines (IMs) are critical components of many industrial processes, what justifies the use of condition-based maintenance (CBM) systems for detecting their faults at an early stage, in order to avoid costly breakdowns of production lines. The development of CBM systems for IMs relies on the use of fast models that can accurately simulate the machine in faulty conditions. In particular, IM models must be able to reproduce the characteristic harmonics that the IM faults impress in the spatial waves of the air gap magneto-motive force (MMF), due to the complex interactions between spatial and time harmonics. A common type of fault is the eccentricity of the rotor core, which provokes an unbalanced magnetic pull, and can lead to destructive rotor-stator rub. Models developed using the finite element method (FEM) can achieve the required accuracy, but their high computational costs hinder their use in online CBM systems. Analytical models are much faster, but they need an inductance matrix that takes into account the asymmetries generated by the eccentricity fault. Building the inductance matrix for eccentric IMs using traditional techniques, such as the winding function approach (WFA), is a highly complex task, because these functions depend on the combined effect of the winding layout and of the air gap asymmetry. In this paper, a novel method for the fast and simple computation of the inductance matrix for eccentric IMs is presented, which decouples the influence of the air gap asymmetry and of the winding configuration using two independent tensors. It is based on the construction of a primitive inductance tensor, which formulates the eccentricity fault using single conductors as the simplest reference frame; and a winding tensor that converts it into the inductance matrix of a particular machine, taking into account the configuration of the windings. The proposed approach applies routine procedures from tensor algebra for performing such transformation in a simple way. It is theoretically explained and experimentally validated with a commercial induction motor with a mixed eccentricity fault.
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BACKGROUND: IgA nephropathy (IgAN) may recur in kidney transplant recipients. B-cell-activating factor (BAFF), a proliferation-inducing ligand (APRIL), and α-defensins are involved in the pathogenesis of native IgAN; however, their role on IgAN recurrence has not been previously analyzed. METHODS: Thirty-five patients with IgAN who received a kidney transplant in our center between January 1, 1993, and December 31, 2015, were included. Recurrence was diagnosed and ruled out in 14 and 11 patients, respectively, by indication biopsies. Pre-transplant, 6-month, 1-, 3-, and 5-year sera selected to measure BAFF, APRIL, and defensin by ELISA. RESULTS: Six months post-transplantation, APRIL levels (300.1 vs 1203.8 pg/mL, P = 0.033) and the mean APRIL values from 6 months to 3 years (409.8 vs 1258.0 pg/mL, P = 0.003) were higher in recurrent patients. Both 6-month APRIL levels (AUC-ROC 0.753, P = 0.033) and mean APRIL values (AUC-ROC 0.844, P = 0.004) discriminated patients with recurrence risk. By logistic regression, APRIL at 6 months (P = 0.044) and mean APRIL (P = 0.021) related to the risk of IgAN recurrence independently. Neither BAFF nor defensin related to recurrence. CONCLUSIONS: Serum APRIL increased at 6 months and mean APRIL remained higher the first 3 years in patients in whom IgAN was going to recur.