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1.
Anal Chem ; 95(2): 1140-1148, 2023 01 17.
Artigo em Inglês | MEDLINE | ID: mdl-36584277

RESUMO

Gaseous potassium (K) species play an important role in biomass combustion processes, and imaging techniques are powerful tools to investigate the related gas-phase chemistry. Here, laser absorption imaging of gaseous atomic K in flames is implemented using tunable diode laser absorption spectroscopy at 769.9 nm and a high-speed complementary metal oxide semiconductor (CMOS) camera recording at 30 kfps. Atomic K absorption spectra are acquired for each camera pixel in a field of view of 28 × 28 mm at a rate of 100 Hz. The technique is used to determine the spatial distribution of atomic K concentration during the conversion of potassium chloride (KCl) salt and wheat straw particles in a laminar premixed CH4/air flame with an image pixel resolution of up to 120 µm. Due to axisymmetry in setup geometry and, consequently, atomic K distributions, the radial atomic K concentration fields could be reconstructed by one-dimensional tomography. For the KCl sample, the K concentration field was in excellent agreement with previous point measurements. In the case of wheat straw, atomic K concentrations of around 3 ppm were observed in a cylindrical flame during devolatilization. In the char conversion phase, a spherical layer of atomic K, with concentrations reaching 25 ppm, was found within 5 mm of the particle surface, while the concentration rapidly decreased to sub-ppm levels along the vertical axis. In both cases, a thin (∼1 mm) layer without any atomic K was observed in close vicinity to the particle, suggesting that the potassium was initially not released in its atomic form.


Assuntos
Cloretos , Potássio , Cloreto de Potássio , Biomassa , Gases , Cloreto de Sódio , Lasers Semicondutores , Halogênios , Tomografia
2.
Psychol Health Med ; 28(6): 1441-1449, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36331176

RESUMO

During the COVID-19 pandemic, undergraduate medical students (UMS) exposed to isolation, social distancing and complete or partial face-to-face educational activities interruption may present increased stress, depression and anxiety. This study was undertaken to evaluate if, during isolation, UMS involved in online group activities as investigators of a research project (volunteer group) would present better mental health than their colleagues, not involved in that research (control group). A Web-based survey, via the Google Forms platform, including details on demographic data, life habits, previous health conditions, worries with the COVID-19 pandemic, sleep pattern modifications and depression, anxiety and mental stress, using the DASS-21 (Depression, Anxiety and Stress Scale) was implemented from 20 July to 31 August 2020. Statistical analysis was performed using the SPSS version 20.0. A p-value <0.05 was significant. A total of 684 UMS were included, 228 as a volunteer group and 456 as a control group. Mean age was 23.15 (3.16) years. The groups were paired for age, gender, ethnicity, life habits and previous health conditions. Older age, male gender, participation in the research project, unchanged sleep pattern during the pandemic, lack of fear from getting the COVID-19 and lack of previous health conditions were associated with lower DASS21 scores (better mental health). Participating as investigators of a research project foreseeing frequent interaction with patients, colleagues and professors (other investigators) lead to better mental health during the COVID-19 quarantine in Brazil.


Assuntos
COVID-19 , Estudantes de Medicina , Humanos , Masculino , Adulto Jovem , Adulto , Pandemias , Brasil/epidemiologia , Saúde Mental , COVID-19/epidemiologia , COVID-19/prevenção & controle , Ansiedade/epidemiologia , Depressão/epidemiologia
3.
Anal Chem ; 94(41): 14242-14250, 2022 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-36197677

RESUMO

Mid-infrared photothermal (MIP) microscopy is a valuable tool for sensitive and fast chemical imaging with high spatial resolution beyond the mid-infrared diffraction limit. The highest sensitivity is usually achieved with heterodyne MIP employing photodetector point-scans and lock-in detection, while the fastest systems use camera-based widefield MIP with pulsed probe light. One challenge is to simultaneously achieve high sensitivity, spatial resolution, and speed in a large field of view. Here, we present widefield mid-infrared photothermal heterodyne (WIPH) imaging, where a digital frequency-domain lock-in (DFdLi) filter is used for simultaneous multiharmonic demodulation of MIP signals recorded by individual camera pixels at frame rates up to 200 kHz. The DFdLi filter enables the use of continuous-wave probe light, which, in turn, eliminates the need for synchronization schemes and allows measuring MIP decay curves. The WIPH approach is characterized by imaging potassium ferricyanide microparticles and applied to detect lipid droplets (alkyne-palmitic acid) in 3T3-L1 fibroblast cells, both in the cell-silent spectral region around 2100 cm-1 using an external-cavity quantum cascade laser. The system achieved up to 4000 WIPH images per second at a signal-to-noise ratio of 5.52 and 1 µm spatial resolution in a 128 × 128 µm field of view. The technique opens up for real-time chemical imaging of fast processes in biology, medicine, and material science.


Assuntos
Microscopia , Ácido Palmítico , Alcinos , Lasers Semicondutores , Microscopia/métodos , Razão Sinal-Ruído
4.
Clin Exp Rheumatol ; 40(7): 1258-1266, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34251312

RESUMO

OBJECTIVES: To evaluate the incidence of COVID-19 and its main outcomes in rheumatic disease (RD) patients on hydroxychloroquine (HCQ) compared to household cohabitants (HC). METHODS: This is a 24-week nationwide prospective multi-centre cohort with a control group without RD and not using HCQ. All participants were monitored through scheduled phone interviews performed by health professionals. Details regarding COVID-19 symptoms, and epidemiological, clinical, and demographic data were recorded on a specific web-based platform. COVID-19 was defined according to the Brazilian Ministry of Health criteria and classified as mild, moderate or severe. RESULTS: A total of 9,585 participants, 5,164 (53.9%) RD patients on HCQ and 4,421 (46.1%) HC were enrolled from March 29th, 2020 to September 30th, 2020, according to the eligibility criteria. COVID-19 confirmed cases were higher in RD patients than in cohabitants [728 (14.1%) vs. 427 (9.7%), p<0.001] in a 24-week follow-up. However, there was no significant difference regarding outcomes related to moderate/ severe COVID-19 (7.1% and 7.3%, respectively, p=0.896). After multiple adjustments, risk factors associated with hospitalisation were age over 65 (HR=4.5; 95%CI 1.35-15.04, p=0.014) and cardiopathy (HR=2.57; 95%CI 1.12-5.91, p=0.026). The final survival analysis demonstrated the probability of dying in 180 days after a COVID-19 diagnosis was significantly higher in patients over 65 years (HR=20.8; 95%CI 4.5-96.1) and with 2 or more comorbidities (HR=10.8; 95%CI 1.1-107.9 and HR=24.8; 95%CI 2.5-249.3, p=0.006, respectively). CONCLUSIONS: Although RD patients have had a higher COVID-19 incidence than individuals from the same epidemiological background, the COVID-19 severity was related to traditional risk factors, particularly multiple comorbidities and age, and not to underlying RD and HCQ.


Assuntos
Tratamento Farmacológico da COVID-19 , COVID-19 , Doenças Reumáticas , COVID-19/epidemiologia , Teste para COVID-19 , Humanos , Hidroxicloroquina/efeitos adversos , Incidência , Estudos Prospectivos , Doenças Reumáticas/diagnóstico , Doenças Reumáticas/tratamento farmacológico , Doenças Reumáticas/epidemiologia , Fatores de Risco , SARS-CoV-2 , Resultado do Tratamento
5.
J Clin Rheumatol ; 2022 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-35699528

RESUMO

BACKGROUND: The coronavirus disease 2019 (COVID-19) pandemic has brought additional burden to patients living with immune-mediated rheumatic diseases (IMRDs), especially at the beginning of 2020, for which information for this population is lacking. METHODS: COnVIDa is a cross-sectional study on patients with IMRD from all regions of Brazil who were invited to answer a specific and customized Web questionnaire about how they were facing the COVID-19 pandemic, especially focusing on health care access, use of medications, and patient-reported outcomes related to IMRD activity. The questionnaire was applied from June 1 to 30, 2020. RESULTS: In total, 1722 of 2576 patients who answered the Web questionnaire were included in the final analysis. Participants were most frequently women, 56% were between 31 and 50 years old, and most (55%) has private health insurance. The most commonly reported IMRD was rheumatoid arthritis (39%), followed by systemic lupus erythematosus (28%). During the study period, 30.7% did not have access to rheumatology consultations, and 17.6% stopped chronic medications. Telemedicine was reported in 44.8% of patients. CONCLUSION: COnVIDa demonstrated a negative impact on health care access and treatment maintenance of patients living with IMRD during the COVID-19 pandemic. However, it also presented an uptake of telemedicine strategies. Data presented in this study may assist future coping policies.

6.
Mol Pharm ; 18(9): 3578-3587, 2021 09 06.
Artigo em Inglês | MEDLINE | ID: mdl-34428059

RESUMO

While theophylline has been extensively studied with multiple polymorphs discovered, there is still currently no conclusive structure for the metastable theophylline form III. In this present work, by combining more widely used techniques such as X-ray diffraction and thermogravimetric analysis with more emerging techniques like low-frequency Raman and terahertz time-domain spectroscopy, to analyze the structure and dynamics of a crystalline system, it was possible to provide further evidence that the form III structure has a theophylline monohydrate structure with the water molecules removed. Solid-state density functional theory simulations were paramount in proving that this proposed structure is correct and explain how vibrational modes within the crystal structures feature and govern polymorphic transitions and the metastable form III. Through the insight provided by both simulated and experimental results, it was possible to decisively conclude the elusive crystal structure of theophylline form III. It was also shown that the correct space group for theophylline monohydrate is not P21/n but, in fact, Pc.


Assuntos
Teofilina/química , Química Farmacêutica/métodos , Estabilidade de Medicamentos , Análise Espectral Raman , Espectroscopia Terahertz , Termogravimetria , Vibração , Difração de Raios X
7.
Int J Vitam Nutr Res ; 87(1-2): 66-74, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27866465

RESUMO

Objectives: The present study aimed to describe the antioxidant dietary intake of patients with fibromyalgia and explore the association of the results with glutathione status, pain, quality of life, and socioeconomic status. METHODS: 38 fibromyalgic female patients and 35 female controls (mean age = 48.6 ± 8.1 and 47.6 ± 10.0 years, respectively) were evaluated. The number of tender points, pain threshold, quality of life, physical activity, socioeconomic status, nutritional status, intake of antioxidant micronutrients and foods with high total antioxidant capacity, and total salivary glutathione were evaluated. RESULTS: The number of tender points, pain threshold, and quality of life were worse in the fibromyalgia group. The consumption of vegetable juices was more common among women with fibromyalgia and consumption of red wine and beer were more common among healthy women. The adjusted mean intakes of antioxidant vitamins as well as selenium were higher for the control group (p ≤ 0.01). There was no difference for salivary levels of glutathione between the groups and no correlation for intake of antioxidant micronutrients and pain or quality of life among fibromyalgic women. However, intake of foods rich in polyphenols was associated with lower numbers of tender points (coffee, r = - 0.346; pear, r = - 0.331) and better quality of life (red fruits, r = - 0.342; dark chocolate, r = - 0.404) in the fibromyalgic group. In these women, associations between glutathione levels and food intake, pain or quality of life were not found. CONCLUSION: This study indicated that antioxidant protection from bioactive compounds present in fruit and vegetables could have an adjuvant role in fibromyalgia treatment.

8.
Adv Rheumatol ; 64(1): 5, 2024 01 02.
Artigo em Inglês | MEDLINE | ID: mdl-38167406

RESUMO

BACKGROUND: Knowledge of patients about Rheumatoid Arthritis (RA) is a necessary aspect to better approach self-management support in a patient-centered manner. The research instrument known as the Rheumatoid Arthritis Knowledge Assessment Scale (RAKAS), consisting of 13 items, is simple, reliable and reproducible, and can be applied in both clinical practice and research protocols. OBJECTIVE: This study aimed to translate and culturally adapt the RAKAS vocabulary into Brazilian Portuguese and to evaluate its concurrent validity. METHODS: The RAKAS was translated into Brazilian Portuguese and administered to 52 elderly women with RA recruited between May 2021 and May 2022. Concurrent validity was assessed using the Spearman's correlation coefficient between RAKAS and Patient Knowledge Questionnaire (PKQ). RESULTS: The participants considered RAKAS-13/BRAZIL easy to understand and did not report any doubts in answering the final version. Concurrent validity of the RAKAS-13/BRAZIL was low compared to the PKQ (ρ = 0.283, p = 0.038). CONCLUSION: The Brazilian Portuguese version of the RAKAS (RAKAS-13/BRASIL) proved to be a questionnaire that was easy and quick to administer to assess patient knowledge about Rheumatoid Arthritis, despite its low correlation with the PKQ in the present study.


Assuntos
Artrite Reumatoide , Comparação Transcultural , Humanos , Feminino , Idoso , Brasil , Reprodutibilidade dos Testes , Inquéritos e Questionários , Artrite Reumatoide/diagnóstico
9.
Med Sci Sports Exerc ; 56(9): 1782-1794, 2024 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-38768034

RESUMO

PURPOSE: To compare the development of fatigability during a moderate-intensity cycling exercise between women with fibromyalgia (FM) and control women (CON) after acute ingestion of caffeine and placebo. METHODS: Ten FM and 10 CON women performed a 30-min moderate-intensity cycling exercise 1 h after the ingestion of a capsule containing either caffeine or a placebo. Fatigability and its central and peripheral determinants were determined via changes from pre- to post-15 and post-30 min of exercise in maximal voluntary isometric contractions, voluntary activation (VA), and quadriceps potentiated twitch torque ( Qtw-pot ), respectively. Heart rate, muscle oxygen saturation, perceptive responses, mood state, localized and widespread pain, and sleepiness were also monitored during and after exercise. RESULTS: There was a time versus group interaction for maximal voluntary isometric contraction and VA ( P < 0.001) but not for Qtw-pot ( P = 0.363), indicating a greater rate of fatigability development, mainly caused by central mechanisms, in the FM than in the CON group. There was also a main effect of condition for VA ( P = 0.011), indicating that caffeine attenuates central mechanisms of fatigability in both groups. Caffeine ingestion also increased muscle oxygenation, perceived vigor, and energy, and decreased leg muscle pain, sleepiness, and perceived fatigue in both groups. However, caffeine improved perceived pleasure/displeasure and exercise adherence likelihood only in the FM group. CONCLUSIONS: Compared with CON, women with FM present a greater rate of fatigability during exercise, mainly of central origin. Caffeine seems to be a promising bioactive to counteract the central mechanisms of fatigability and improve the exercise experience among FM women.


Assuntos
Ciclismo , Cafeína , Fibromialgia , Contração Isométrica , Humanos , Feminino , Cafeína/administração & dosagem , Cafeína/farmacologia , Fibromialgia/fisiopatologia , Fibromialgia/tratamento farmacológico , Adulto , Ciclismo/fisiologia , Fadiga Muscular/efeitos dos fármacos , Fadiga Muscular/fisiologia , Consumo de Oxigênio/efeitos dos fármacos , Afeto/efeitos dos fármacos , Frequência Cardíaca , Pessoa de Meia-Idade , Estimulantes do Sistema Nervoso Central/administração & dosagem , Exercício Físico/fisiologia , Músculo Quadríceps/metabolismo , Músculo Quadríceps/efeitos dos fármacos , Torque , Fadiga , Método Duplo-Cego
10.
Pharmaceutics ; 16(7)2024 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-39065608

RESUMO

In diabetic ulcers, an increased secretion of human neutrophil elastase (HNE) and bacterial infections play crucial roles in hindering healing. Considering that, the present study proposed the development of multi-action polycaprolactone (PCL)/polyethylene glycol (PEG) electrospun fibers incorporating elastase-targeting peptides, AAPV and WAAPV, via blending. Characterization confirmed WAAPV's efficacy in regulating proteolytic enzymes by inhibiting HNE. The engineered fibers, particularly those containing PEG, exhibited optimal wettability but an accelerated degradation that was mitigated with the peptide's inclusion, thus promoting a sustained peptide release over 24 h. Peptide loading was verified indirectly through thermal stability and hydration capacity studies (hydrophobic bonding between PCL and WAAPV and hydrophilic affinities between PCL/PEG and AAPV) and determined at ≈51.1 µg/cm2 and ≈46.0 µg/cm2 for AAPV and ≈48.5 µg/cm2 and ≈51.3 µg/cm2 for WAAPV, respectively, for PCL and PCL/PEG. Both AAPV and WAAPV effectively inhibited HNE, with PEG potentially enhancing this effect by interacting with the peptides and generating detectable peptide-PEG complexes (≈10% inhibition with PCL + peptide fibers after 6 h of incubation, and ≈20% with PCL/PEG + peptide fibers after 4 h incubation). Peptide-loaded fibers demonstrated antibacterial efficacy against Staphylococcus aureus (up to ≈78% inhibition) and Escherichia coli (up to ≈66% inhibition), with peak effectiveness observed after 4 and 2 h of incubation, respectively. This study provides initial insights into the WAAPV's potential for inhibiting HNE and bacteria activities, showing promise for applications in diabetic ulcer management.

11.
BMC Musculoskelet Disord ; 14: 188, 2013 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-23767857

RESUMO

BACKGROUND: Patients and physicians from three Latin American (LA) and six European countries were surveyed in order to describe differences in journey to diagnosis, impact, and management of fibromyalgia (FM). METHODS: 900 patients (300 LA; 600 Europe) and 1824 physicians (604 LA; 1220 Europe) were surveyed between October-December 2010 (LA) and February-April 2008 (Europe). Patients and physicians (GP or specialists) completed separate questionnaires, on symptoms, impact, and FM management. Interviews were conducted in local languages. Appropriate rating scales were used throughout. Data were analyzed using cross-tabulations and descriptive statistics. Significance was determined at P<0.05 (indicated by *). RESULTS: In LA versus Europe, patients reported having FM symptoms for longer (100.8 vs. 83.7* months), and taking longer to be diagnosed (42.3 vs. 31.1* months). FM was characterized by multiple symptoms (11.2 vs. 6.9), but more LA patients reported 14 common symptoms*, and rated pain higher on 11-point scale (8.0 vs. 7.2*). LA patients were taking fewer medications (3.3 vs. 4.0). Patients from both regions found common symptoms very/extremely disruptive to their quality of life, but symptoms impacted daily living and ability to work more significantly in LA. Physicians (GPs or specialists) from LA more often considered problems sleeping*, difficulty concentrating*, anxiety*, depression*, numbness/tingling*, and leg cramps* very/extremely disruptive vs. European physicians. Despite headache, heightened sensitivity to touch, difficulty concentrating, and joint pain being experienced by ≥50% of patients from both regions, <15% of PCPs or specialists considered these typical FM symptoms. Patients also considered 12/14 symptoms more disruptive than PCPs or specialists in the same region. However, a higher proportion of PCPs or specialists considered FM to have a strong/very strong impact on aspects of daily living vs. patients within the same region. CONCLUSIONS: Patient- and physician-rated disease perception and impact was often higher in LA than in Europe. Patient and physician perspective concerning FM impact and disruption were often misaligned within the same region. Our observations may be representative of cultural differences in stoicism, expression, beliefs, and attitudes to pain perception and management. Better understanding of these complexities could help targeted educational/training programs incorporating cultural differences, to improve chronic care.


Assuntos
Gerenciamento Clínico , Fibromialgia/diagnóstico , Inquéritos Epidemiológicos , Satisfação do Paciente , Relações Médico-Paciente , Padrões de Prática Médica/estatística & dados numéricos , Adolescente , Adulto , Idoso , Europa (Continente) , Feminino , Fibromialgia/fisiopatologia , Fibromialgia/terapia , Humanos , América Latina , Masculino , Pessoa de Meia-Idade , Dor , Medição da Dor , Qualidade de Vida , Adulto Jovem
12.
Adv Rheumatol ; 63(1): 47, 2023 09 07.
Artigo em Inglês | MEDLINE | ID: mdl-37679833

RESUMO

INTRODUCTION/OBJECTIVES: Psoriatic arthritis (PsA) is a chronic multisystem osteoarticular disease that requires specialized care. Most Brazilians depend on the public healthcare provided by the Unified Health System (Sistema Único de Saúde, SUS). This study aimed to describe the epidemiological characteristics of patients with PsA in follow-up in SUS, focusing on the incidence and prevalence of the disease, comorbidities, and hospitalizations. METHODS: We collected data from the Outpatient Data System of SUS (Sistema de Informações Ambulatoriais do SUS, SIA/SUS) regarding outpatient visits and hospitalizations in the Brazilian public healthcare system from January 2008 to March 2021 using the Techtrials Disease Explorer® platform and the medical code related to PsA were selected. RESULTS: We evaluated 40,009 patients and found a prevalence of 24.4 cases of visits due to PsA per 100,000 patients in follow-up in SUS. Female patients were predominant (54.38%). The incidence of visits due to PsA has been increasing in recent years and we observed an incidence of 8,982 new visits in 2020. The main comorbidities of these patients were osteoarthritis, lower back pain, shoulder injuries, oncological diseases, crystal arthropathies, and osteoporosis. Hospitalizations were mainly due to treating clinical or cardiovascular conditions and performing orthopedic procedures. CONCLUSION: The number of visits due to PsA in SUS has increased in recent years, mainly on account of new diagnoses of the disease, although the prevalence found in this study's population was lower than that observed in the general population.


Assuntos
Artrite Psoriásica , Doenças Cardiovasculares , Humanos , Feminino , Artrite Psoriásica/epidemiologia , Brasil/epidemiologia , Seguimentos , Hospitalização
13.
Minerva Obstet Gynecol ; 75(5): 424-431, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35686636

RESUMO

BACKGROUND: Fibromyalgia women (FM) seems to get worse at menopause suggesting some influence of estrogens on its pathophysiology. We aimed to study the influence of postmenopausal hormone therapy (HT) in FM, the relationship with sleep and FM impact. METHODS: We analyzed prospectively 69 menopausal women, divided in two groups, FM group (FMG; N.=32) and comparison group (CG; N.=28) submitted to HT for twelve weeks (1.2 mg/g transdermal estradiol, 100 mg micronized natural progesterone oral/daily). Data on Utian Quality of Life Questionnaire (UQOL) and Pittsburgh Sleep Quality Index (PSQI) were obtained in both groups, at entrance and twelve weeks after HT. FM patients also completed the Fibromyalgia Impact Questionnaire - Revised (FIQ-R) and fibromyalgia severity (FS). RESULTS: FM patients improved significantly the FIQ-R (P=0.0001, median FIQ-R score 30% lower), mainly the severity of FM, assessed by FS (P<0.0001). Both groups had improved quality of life and sleep (UQOL: P=0.0001; P=0.001, PSQI: P<0.0001; P=0.007, respectively). Differences between first and second PSQI were greater for CG than for FMG (P=0.008). CONCLUSIONS: HT improving sleep and quality of life in both groups; it was a significant clinical improvement seen by FIQ and FS in FM patients. These changes characterize improvement of functional status and symptoms severity.


Assuntos
Terapia de Reposição de Estrogênios , Fibromialgia , Menopausa , Feminino , Humanos , Fibromialgia/tratamento farmacológico , Fibromialgia/diagnóstico , Qualidade de Vida , Sono
14.
J Appl Clin Med Phys ; 13(1): 3671, 2012 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-22231219

RESUMO

The skyshine radiation phenomenon consists of the scattering of primary photon beams in the atmosphere above the roof of a medical linear accelerator facility, generating an additional dose at ground level in the vicinity of the treatment room. Thus, with respect to radioprotection, this situation plays an important role when the roof is designed with little shielding and there are buildings next to the radiotherapy treatment room. In literature, there are few reported skyshine-measured doses and these contain poor agreement with empirical calculations. In this work, we carried out measurements of skyshine photon dose rates produced from eight different 6 and 10 MV medical accelerators. Each measurement was performed outside the room facility, with the beam positioned in the upward direction, at a horizontal distance from the target and for a 40 cm × 40 cm maximum photon field size at the accelerator isocenter. Measured dose-equivalent rates results were compared with calculations obtained by an empirical expression, and differences between them deviated in one or more order of magnitude.


Assuntos
Exposição Ocupacional/análise , Aceleradores de Partículas , Fótons , Doses de Radiação , Monitoramento de Radiação/métodos , Proteção Radiológica/métodos , Análise de Falha de Equipamento , Espalhamento de Radiação
15.
Spectrochim Acta A Mol Biomol Spectrosc ; 264: 120302, 2022 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-34461522

RESUMO

This paper describes a new method to obtain NIR spectra of liquid and gas samples by diffuse reflectance, which is especially suitable for handheld spectrophotometers, since most of these instruments are designed to acquire spectrum using this geometry. The core of the method is a diffuse reflectance cell, which consists of a vial containing a mixture of the liquid or gas sample (rare medium) and a powder (dense medium). Using this strategy, no adaptation is required to measure spectra with most portable NIR spectrometers. This new method was used to obtain NIR spectra of several liquids and gases, which were compared with traditional transmittance spectra. As a proof of concept, measurements of biodiesel/vegetable oil/diesel blends were used to build multivariate calibrations to predict the contents of biodiesel and vegetable oil in diesel blends using benchtop and handheld FT-NIR spectrophotometers. This low-cost method was demonstrated to be suitable for overcoming problems related to the handling of viscous samples and expand the applications with portable NIR instruments.


Assuntos
Biocombustíveis , Espectroscopia de Luz Próxima ao Infravermelho , Calibragem , Gases , Óleos de Plantas
16.
J Bras Pneumol ; 48(6): e20220145, 2022.
Artigo em Inglês, Português | MEDLINE | ID: mdl-36477171

RESUMO

OBJECTIVE: To assess the risk factors for interstitial lung disease (ILD) in patients with rheumatoid arthritis (RA) and to evaluate the association of ILD with the use of methotrexate as well as with joint disease activity. METHODS: A retrospective, cross-sectional study conducted between March and December 2019 at a tertiary healthcare center, in a follow-up of RA patients who had undergone pulmonary function tests (PFT) and chest computed tomography. We evaluated the tomographic characteristics, such as the presence of ILD and its extension, as well as joint disease activity. Functional measurements, such as forced vital capacity (FVC) and diffusing capacity for carbon monoxide (DLCO), were also assessed. After this, a multivariate logistic regression analysis was applied in order to identify risk factors associated with ILD. RESULTS: We evaluated 1.233 patients, of which 134 were eligible for this study. The majority were female (89.6%), with a mean age of 61 years old and with a positive rheumatoid factor (86.2%). RA-associated ILD (RA-ILD) was detected in 49 patients (36.6%). We found an association of RA-ILD with age ≥= 62 year, male sex, smoking history and fine crackles in lung auscultation and a decreased DLCO. The indicators of being aged ≥ 62 years old and having moderate or high RA disease activity were both independent factors associated with RA-ILD, with an odds ratio of 4.36 and 3.03, respectively. The use of methotrexate was not associated with a higher prevalence of ILD. CONCLUSION: Age and RA disease activity are important risk factors associated with RA-ILD. Methotrexate was not associated with the development of RA-ILD in the present study.


OBJETIVO: Avaliar os fatores de risco para doença pulmonar intersticial (DPI) em pacientes com artrite reumatoide (AR), bem como a associação com uso de metotrexate e com a atividade da doença articular. MÉTODOS: Estudo retrospectivo, transversal, realizado entre março e dezembro de 2019 em um centro de saúde terciário, no seguimento de pacientes com AR submetidos a provas de função pulmonar (PFP) e tomografia computadorizada de tórax. Avaliamos as características tomográficas, como a presença de DPI e sua extensão, bem como a atividade da doença articular. Medidas funcionais, como capacidade vital forçada (CVF) e a medida de difusão de monóxido de carbono (DCO) também foram avaliadas. Em seguida, aplicou-se uma análise de regressão logística multivariada para identificar os fatores de risco associados à DPI. RESULTADOS: Foram avaliados 1.233 pacientes, dos quais 134 foram elegíveis para este estudo. A maioria era do sexo feminino (89,6%), com idade média de 61 anos e fator reumatoide positivo (86,2%). A DPI associada à AR (DPI-AR) foi detectada em 49 pacientes (36,6%). Encontramos associação de DPI-AR com idade ≥ 62 anos, sexo masculino, história de tabagismo,crepitações finas na ausculta pulmonar e diminuição da DCO. Idade ≥ 62 anos e atividade articular moderada ou alta da AR foram fatores independentes associados à DPI-AR, com odds ratio de 4,36 e 3,03, respectivamente. O uso de metotrexato não foi associado à maior prevalência de DPI. CONCLUSÃO: A idade e a atividade da doença da AR são importantes fatores de risco associados à DPI-AR. O metotrexato não foi associado ao desenvolvimento de DPI-AR no presente estudo.


Assuntos
Artrite Reumatoide , Doenças Pulmonares Intersticiais , Humanos , Feminino , Masculino , Pessoa de Meia-Idade , Estudos Transversais , Estudos Retrospectivos , Doenças Pulmonares Intersticiais/etiologia , Artrite Reumatoide/complicações , Artrite Reumatoide/tratamento farmacológico , Fatores de Risco
17.
Adv Rheumatol ; 62(1): 13, 2022 05 03.
Artigo em Inglês | MEDLINE | ID: mdl-35505408

RESUMO

BACKGROUND: Patients using immunosuppressive drugs may have unfavorable results after infections. However, there is a lack of information regarding COVID-19 in these patients, especially in patients with rheumatoid arthritis (RA). Therefore, the aim of this study was to evaluate the risk factors associated with COVID-19 hospitalizations in patients with RA. METHODS: This multicenter, prospective cohort study is within the ReumaCoV Brazil registry and included 489 patients with RA. In this context, 269 patients who tested positive for COVID-19 were compared to 220 patients who tested negative for COVID-19 (control group). All patient data were collected from the Research Electronic Data Capture database. RESULTS: The participants were predominantly female (90.6%) with a mean age of 53 ± 12 years. Of the patients with COVID-19, 54 (20.1%) required hospitalization. After multiple adjustments, the final regression model showed that heart disease (OR = 4.61, 95% CI 1.06-20.02. P < 0.001) and current use of glucocorticoids (OR = 20.66, 95% CI 3.09-138. P < 0.002) were the risk factors associated with hospitalization. In addition, anosmia was associated with a lower chance of hospitalization (OR = 0.26; 95% CI 0.10-0.67, P < 0.005). CONCLUSION: Our results demonstrated that heart disease and the use of glucocorticoids were associated with a higher number of hospital admissions for COVID-19 in patients with RA. TRIAL REGISTRATION: Brazilian Registry of Clinical Trials - RBR-33YTQC.


Assuntos
Artrite Reumatoide , COVID-19 , Cardiopatias , Adulto , Idoso , Artrite Reumatoide/complicações , Artrite Reumatoide/tratamento farmacológico , Artrite Reumatoide/epidemiologia , Brasil/epidemiologia , Feminino , Glucocorticoides , Hospitalização , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Sistema de Registros
18.
Adv Rheumatol ; 62(1): 3, 2022 01 17.
Artigo em Inglês | MEDLINE | ID: mdl-35039077

RESUMO

OBJECTIVE: To provide guidelines on the coronavirus disease 2019 (COVID-19) vaccination in patients with immune-mediated rheumatic diseases (IMRD) to rheumatologists considering specific scenarios of the daily practice based on the shared-making decision (SMD) process. METHODS: A task force was constituted by 24 rheumatologists (panel members), with clinical and research expertise in immunizations and infectious diseases in immunocompromised patients, endorsed by the Brazilian Society of Rheumatology (BSR), to develop guidelines for COVID-19 vaccination in patients with IMRD. A consensus was built through the Delphi method and involved four rounds of anonymous voting, where five options were used to determine the level of agreement (LOA), based on the Likert Scale: (1) strongly disagree; (2) disagree, (3) neither agree nor disagree (neutral); (4) agree; and (5) strongly agree. Nineteen questions were addressed and discussed via teleconference to formulate the answers. In order to identify the relevant data on COVID-19 vaccines, a search with standardized descriptors and synonyms was performed on September 10th, 2021, of the MEDLINE, EMBASE, Cochrane Central Register of Controlled Trials, ClinicalTrials.gov, and LILACS to identify studies of interest. We used the Newcastle-Ottawa Scale to assess the quality of nonrandomized studies. RESULTS: All the nineteen questions-answers (Q&A) were approved by the BSR Task Force with more than 80% of panelists voting options 4-agree-and 5-strongly agree-, and a consensus was reached. These Guidelines were focused in SMD on the most appropriate timing for IMRD patients to get vaccinated to reach the adequate covid-19 vaccination response. CONCLUSION: These guidelines were developed by a BSR Task Force with a high LOA among panelists, based on the literature review of published studies and expert opinion for COVID-19 vaccination in IMRD patients. Noteworthy, in the pandemic period, up to the time of the review and the consensus process for this document, high-quality evidence was scarce. Thus, it is not a substitute for clinical judgment.


Assuntos
COVID-19 , Doenças Reumáticas , Vacinação/métodos , Vacinas contra COVID-19 , Humanos , Reumatologia , SARS-CoV-2
19.
J Appl Clin Med Phys ; 12(2): 3330, 2011 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-21587175

RESUMO

The Brazilian Institute of Radiation Protection and Dosimetry (IRD/CNEN) carried out quality assurance regulatory audits in Brazilian radiotherapy facilities from 1995 to 2007. In this work, the set of data collected from 195 radiotherapy facilities that use high-energy photon beams are analyzed. They include results from audits in linear electron accelerators and/or Co-60 units. The inspectors of IRD/CNEN performed the dosimetry of high-energy radiotherapy photon beams according to the IAEA dosimetry protocols TRS 277 and TRS 398, and the values of measurements were compared to stated values. Other aspects of radiological protection were checked during on-site audits such as calibration certification of clinical dosimeters and portable monitors, existence and use of check source, use of barometer and thermometer, individual dose registry and training of staff. It was verified that no check source was available in 38% of the visited facilities; the training of personnel was not adequate in 9% of the facilities and the registry of accumulated individual doses was not being done in 6% of the facilities. Measurements of absorbed dose have indicated deviations in the range ± 3% for 67.6% of the cobalt-60 units and 79.6% of medical linear accelerators; 18.5% of Co-60 irradiators and 9.6% of linear accelerators presented deviations in the range 3% < δ ≤ 5%. Finally, 13.9% of Co-60 facilities and 10.8% of linear accelerator facilities presented dosimetry deviations above 5%. The effort in dosimetric quality control performed by IRD/CNEN audits has yielded positive changes that make radiation treatment facilities more reliable.


Assuntos
Radiometria/métodos , Radioterapia de Alta Energia/métodos , Brasil , Calibragem , Isótopos do Cobalto/química , Humanos , Aceleradores de Partículas , Controle de Qualidade , Radioterapia (Especialidade)/normas , Proteção Radiológica/métodos , Dosagem Radioterapêutica , Radioterapia de Alta Energia/normas , Segurança , Termômetros
20.
Data Brief ; 34: 106620, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33365366

RESUMO

Beta particles radiation doses have important applications in medicine. In particular, curved and symmetric as well as curved and asymmetric applicators containing the beta emitting 106 Ru/ 106 Rh isotopes are widely used in radiotherapy for the treatment of various ocular diseases. Nevertheless, a great problem in the use of these applicators is the inaccurate determination of the dose rates around them. Difficulties arise mainly because of the very short distances involved, and in this scenario theoretical calculation methods play an important role. In this work a simple approach based on the beta-point dose function integration over the total surface of each plaque was used to estimate the dose rates along their central axis. Results of relative dose rates for concave and symmetric (CCA, CCB, CXS, CCX/Y/Z, CCD, CGD and CCC) and concave and asymmetric (CIA, CIB/CIB-2, COB and COC) ruthenium/rhodium plaque types are shown.

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