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1.
J Microsc ; 2024 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-38874394

RESUMO

Nanoporous gold electrodes are of great interest in electroanalytical chemistry, because of their unusual activity and large surface area. The electrochemical activity can be further improved by coating with molecular catalysts such as the tetraruthenated cobalt-tetrapyridylporphyrazines investigated in this work. The plasmonic enhancement of the scattered light at the nanoholes and borders modifies the electrode's optical characteristics, improving the transmission through the surface-enhanced Raman scattering (SERS) effect. When monitored by hyperspectral dark-field and confocal Raman microscopy, this effect allows probing of the porphyrazine species at the plasmonic nanholes, improving the understanding of the chemically modified gold electrodes.

2.
J Surg Oncol ; 2024 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-38979906

RESUMO

Traditionally, lobectomy was standard for stage IA non-small-cell lung cancer (NSCLC). Recent RCTs suggest sublobar resection's comparable outcomes. Our meta-analysis, incorporating 30 studies (including four RCTs), assessed sublobar resection's efficacy. Employing a random-effects model and I2 statistics for heterogeneity, we found sublobar resection reduced DFS (HR 1.31, p < 0.01) and OS (HR 1.27, p < 0.01) overall. However, RCT subgroup analysis showed no significant differences in DFS (p = 0.28) or OS (p = 0.62). Sublobar resection is a viable option for well-selected patients.

3.
J Med Internet Res ; 26: e48464, 2024 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-38857068

RESUMO

BACKGROUND: The COVID-19 pandemic represented a great stimulus for the adoption of telehealth and many initiatives in this field have emerged worldwide. However, despite this massive growth, data addressing the effectiveness of telehealth with respect to clinical outcomes remain scarce. OBJECTIVE: The aim of this study was to evaluate the impact of the adoption of a structured multilevel telehealth service on hospital admissions during the acute illness course and the mortality of adult patients with flu syndrome in the context of the COVID-19 pandemic. METHODS: A retrospective cohort study was performed in two Brazilian cities where a public COVID-19 telehealth service (TeleCOVID-MG) was deployed. TeleCOVID-MG was a structured multilevel telehealth service, including (1) first response and risk stratification through a chatbot software or phone call center, (2) teleconsultations with nurses and medical doctors, and (3) a telemonitoring system. For this analysis, we included data of adult patients registered in the Flu Syndrome notification databases who were diagnosed with flu syndrome between June 1, 2020, and May 31, 2021. The exposed group comprised patients with flu syndrome who used TeleCOVID-MG at least once during the illness course and the control group comprised patients who did not use this telehealth service during the respiratory illness course. Sociodemographic characteristics, comorbidities, and clinical outcomes data were extracted from the Brazilian official databases for flu syndrome, Severe Acute Respiratory Syndrome (due to any respiratory virus), and mortality. Models for the clinical outcomes were estimated by logistic regression. RESULTS: The final study population comprised 82,182 adult patients with a valid registry in the Flu Syndrome notification system. When compared to patients who did not use the service (n=67,689, 82.4%), patients supported by TeleCOVID-MG (n=14,493, 17.6%) had a lower chance of hospitalization during the acute respiratory illness course, even after adjusting for sociodemographic characteristics and underlying medical conditions (odds ratio [OR] 0.82, 95% CI 0.71-0.94; P=.005). No difference in mortality was observed between groups (OR 0.99, 95% CI 0.86-1.12; P=.83). CONCLUSIONS: A telehealth service applied on a large scale in a limited-resource region to tackle COVID-19 was related to reduced hospitalizations without increasing the mortality rate. Quality health care using inexpensive and readily available telehealth and digital health tools may be delivered in areas with limited resources and should be considered as a potential and valuable health care strategy. The success of a telehealth initiative relies on a partnership between the involved stakeholders to define the roles and responsibilities; set an alignment between the different modalities and levels of health care; and address the usual drawbacks related to the implementation process, such as infrastructure and accessibility issues.


Assuntos
COVID-19 , Telemedicina , Humanos , COVID-19/mortalidade , Brasil/epidemiologia , Estudos Retrospectivos , Telemedicina/estatística & dados numéricos , Feminino , Masculino , Pessoa de Meia-Idade , Adulto , Idoso , Hospitalização/estatística & dados numéricos , Pandemias , SARS-CoV-2 , Influenza Humana/mortalidade , Influenza Humana/epidemiologia , Estudos de Coortes
4.
Rev Panam Salud Publica ; 48: e52, 2024.
Artigo em Português | MEDLINE | ID: mdl-38859811

RESUMO

Objective: To describe temporal and spatial patterns and identify the factors associated with the incidence of HIV/AIDS among young people in Brazil. Method: Ecological study of young Brazilians aged 15-24 years with reported HIV/AIDS, from 2001 to 2021. The Joinpoint method was used for the temporal analysis. Spatial clusters were detected using Bayesian methods, spatial autocorrelation, Getis-Ord Gi*, and scan techniques. Four non-spatial and spatial regression models were used to identify factors associated with the result. All statistical analyses considered p < 0.05. Results: In Brazil, the average incidence was 12.29 per 100 000 inhabitants, with an annual increase of 7.3% in the period 2007-2014 and a subsequent 3.4% decrease in 2014-2021. A high-high pattern and hotspots were observed, mainly in municipalities in the South, Southeast, Central-West, and North regions. The primary cluster was located in 572 municipalities in Rio Grande do Sul and Santa Catarina, with the highest relative risks in Manaus (Amazonas) and Rondonópolis (Mato Grosso). The illiteracy rate (ß = -0.08), GINI Index (ß = -3.74) and Family Health Strategy coverage (ß = -0.70) were negatively associated with the result. In contrast, the Firjan Municipal Development Index (ß = 2.37), Social Vulnerability Index (ß = 6.30), percentage of Bolsa Família recipients (ß = 0.04), and per capita income (ß = 0.008) showed a positive association. Conclusion: There was an upward trend in the incidence of HIV/AIDS until 2014, followed by a decline until 2021. High-rate clusters were concentrated in municipalities in the North, South, Southeast and Central-West regions in particular. Indicators of socioeconomic vulnerability had positive or negative effects on the result, depending on the territory investigated.


Objetivo: Describir el patrón temporal y espacial, y determinar los factores asociados a la incidencia de infección por el VIH/sida en jóvenes en Brasil. Método: Estudio ecológico en jóvenes brasileños de 15 a 24 años con diagnóstico de infección por el VIH/sida en el período 2001-2021. Para el análisis temporal se utilizó el método de regresión de puntos de inflexión (joinpoint). Los conglomerados espaciales se detectaron con métodos Bayesianos y de autocorrelación espacial, Gi* de Getis-Ord y escaneo. Se utilizaron cuatro modelos de regresión espacial y no espacial para detectar los factores asociados al resultado. En todos los análisis estadísticos se estableció un valor de p < 0,05 como umbral de significación. Resultados: En Brasil, la incidencia media fue de 12,29 por 100 000 habitantes, con un aumento del 7,3% anual en el período 2007-2014 y una reducción posterior del 3,4% en el período 2014-2021. Se observó un patrón alto/alto y la presencia de puntos calientes, principalmente en municipios del Sur, Sudeste, Centro-Oeste y Norte. El principal conglomerado se localizó en 572 municipios de Rio Grande do Sul y Santa Catarina, y los riesgos relativos más altos se observaron en Manaus (Amazonas) y Rondonópolis (Mato Grosso). La tasa de analfabetismo (ß = -0,08), el índice de Gini (ß = -3,74) y la cobertura de la estrategia de salud familiar (ß = -0,70) mostraron una asociación negativa con el resultado. En cambio, el índice de Firjan de desarrollo municipal (ß = 2,37), el índice de vulnerabilidad social (ß = 6,30), el porcentaje de personas que reciben ayuda del programa de bienestar social Bolsa Família (ß = 0,04) y los ingresos per cápita (ß = 0,008) mostraron una asociación positiva. Conclusión: Hubo una tendencia al aumento de la incidencia de infección por el VIH/sida hasta el 2014, con una reducción posterior hasta el 2021. Los conglomerados de tasas elevadas se concentraron especialmente en los municipios de las regiones Norte, Sur, Sudeste y Centro-Oeste. Los indicadores de vulnerabilidad socioeconómica tienen una influencia positiva o negativa en el resultado, según el territorio investigado.

5.
Am Heart J ; 262: 119-130, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37044364

RESUMO

BACKGROUND: Hypertension and diabetes mellitus (DM) are highly prevalent in low and middle-income countries (LMICs), and the proportion of patients with uncontrolled diseases is higher than in high-income countries. Innovative strategies are required to surpass barriers of low sources, distance and quality of health care. Our aim is to assess the uptake and effectiveness of the implementation of an integrated multidimensional strategy in the primary care setting, for the management of people with hypertension and diabetes mellitus in Brazil. METHODS: This scale up implementation study called Control of Hypertension and diAbetes in MINas Gerais (CHArMING) Project has mixed-methods, and comprehends 4 steps: (1) needs assessment, including a standardized structured questionnaire and focus groups with health care practitioners; (2) baseline period, 3 months before the implementation of the intervention; (3) cluster randomized controlled trial (RCT) with a 12-months follow-up period; and (4) a qualitative study after the end of follow-up. The cluster RCT will randomize 35 centers to intervention (n = 18) or usual care (n = 17). Patients ≥18 years old, with diagnosis of hypertension and/or DM, of 5 Brazilian cities in a resource-constrained area will be enrolled. The intervention consists of a multifaceted strategy, with a multidisciplinary approach, including telehealth tools (decision support systems, short message service, telediagnosis), continued education with an approach to issues related to the care of people with hypertension and diabetes in primary care, including pharmacological and non-pharmacological treatment and behavioral change. The project has actions focused on professionals and patients. CONCLUSIONS: This study consists of a multidimensional strategy with multidisciplinary approach using digital health to improve the control of hypertension and/or DM in the primary health care setting. We expect to provide the basis for implementing an innovative management program for hypertension and DM in Brazil, aiming to reduce the present and future burden of these diseases in Brazil and other LMICs. CLINICAL TRIAL IDENTIFIER: This study was registered in ClinicalTrials.gov. (NCT05660928).


Assuntos
Diabetes Mellitus , Hipertensão , Humanos , Adolescente , Brasil/epidemiologia , Hipertensão/tratamento farmacológico , Diabetes Mellitus/epidemiologia , Diabetes Mellitus/terapia , Atenção à Saúde , Atenção Primária à Saúde/métodos , Ensaios Clínicos Controlados Aleatórios como Assunto
6.
Telemed J E Health ; 29(7): 1043-1050, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36445772

RESUMO

Introduction: Data addressing the economic aspects of telehealth initiatives are incipient. This study aimed to evaluate the labor costs for running a COVID-19 telehealth system and its potential incremental access to health care service. Methods: From July 2020 to July 2021, data from a Brazilian teleconsultation service were analyzed. Labor costs were estimated by time-driven activity-based costing. A Generalized Reduced Gradient solving method was coded to maximize the mean incremental access rate and two scenarios were considered to compare the teleconsultation with the in-person consultation: (1) only the length of time that patients spent with a clinician in an in-person consultation was accounted and (2) in addition to the medical consultation, nursing screening was accounted. The mean incremental access rate of the teleconsultation service was defined as a maximization objective in the model. Results: Mean labor costs per medical and nursing teleconsultations are Int$ 24 and Int$ 10, based on data analyses from 25,258 patients. Telemonitoring a patient with a daily call for 7 days costs, on average, Int$ 14. COVID-19 teleconsultation service represents, on average, an incremental access to medical consultation rate of 35% to 52% (min 23% max 63%) for the scenarios (1) and (2), respectively, and considering the current consumed budget for this service. Discussion: A COVID-19 telehealth service contributes to increasing access to the health care system without increasing costs. These services can be included in the bundle of care strategies offered in a national public health care system that looks for more sustainable strategies to provide care.


Assuntos
COVID-19 , Consulta Remota , Telemedicina , Humanos , COVID-19/epidemiologia , Atenção à Saúde , Telemedicina/métodos , Brasil/epidemiologia
7.
Planta ; 257(1): 19, 2022 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-36538159

RESUMO

MAIN CONCLUSION: Anastomosed laticifers with intrusive growth produce latex containing methyl comate and betulin with economic and ecological value in arid environments. Climatic factors influence laticifer development in the apical meristem and vascular cambium. Latex is a complex emulsion with high medicinal as well as ecological value related to plant survival. Marsdenia zehntneri is a shrubby plant that grows on limestone outcrops in the semiarid regions of Brazil. We sought to characterize the ontogenesis of the laticifers of this species and to relate that process to climatic seasonality and phenology through anatomical, ultrastructural, and micro-morphometric evaluations of the apical meristem and vascular cambium. The histochemistry of the secretory structure was investigated and the chemical composition of the latex was analyzed. Phenological assessments were performed by monitoring phenological events for 1 year. The laticifers network of M. zehntneri permeates the entire primary and secondary body of the plant, providing a wide distribution system of defensive compounds. Its laticifers, of a distinct mixed type (anastomosed, with intrusive growth), are numerous and voluminous in the apical meristem but scarce and minute in the secondary phloem. Latex secretion involves the participation of oleoplasts, polysomes, and dictyosomes. Methyl 2,3-dihydroxy-ursan-23-oate, methyl 3-hydroxy-ursan-23-oate, and betulin are encountered in high proportions in the latex and have ecological and medicinal functions. The development of primary laticifers is related to the resumption of apical meristem activity with increasing day length at the end of the austral winter. The development of secondary laticifers is related to high summer temperatures and rainfall that favor vascular cambium activity. The wide distribution of laticifers, their seasonal pattern of secretion, and their latex composition contribute to the adaptation of M. zehntneri to its natural environment.


Assuntos
Apocynaceae , Marsdenia , Látex , Meristema
8.
Microsc Microanal ; : 1-12, 2022 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-35314015

RESUMO

The objective of this work was to characterize the ontogenesis of Protium spruceanum secretory ducts, to evaluate the effects of seasonality on that process, and to characterize the chemical nature of the resin. Morphometric, anatomical, micromorphometric, histochemical, and ultrastructural evaluations of shoot apexes and chemical analyses of the resin were performed. The ducts of schizolysigenous origin are distributed in the primary and secondary phloem. The subsecretory tissue is meristematic and can restore the secretory epithelium. Secretory epithelial cells have wall thickening resembling that of the Casparian strip that regulates secretion reflux. The main resin compounds are pentacyclic triterpenoids, α- and ß-amyrins, and α- and ß-amyrenones, which are reported here for the first time for this species. The presence of electron-dense and electron-opaque structures, in the secretory epithelial cells, are compatible with the triterpenes and mucilage identified in the resin. Rising temperatures, rainfall, and increasing day length induce the formation of ducts in the vascular cambium throughout Spring/Summer. The abundant production of resin rich in pentacyclic triterpenes indicates the potential use of the species for medicinal and cosmetic purposes. The understanding that secretory processes are concentrated during the Spring/Summer seasons will contribute to the definition of resin extraction management strategies.

9.
Rapid Commun Mass Spectrom ; 35(16): e9132, 2021 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-34038980

RESUMO

RATIONALE: In this work we investigate the single-photon double ionization of the SUVA 134a (1,1,1,2-tetrafluoroethane) molecule in the energy range from 21.21 to 320 eV. Our experimental data are supported by Thomas' and Samson's models. It is shown that the double photoionization of the SUVA 134a can be expressed as a sum of the so-called shake-off (SO) and the knockout (KO) processes. METHODS: The experiments were executed at the TGM beamline at Laboratório Nacional de Luz Síncrotron in Campinas, Brazil. The source of EUV and X-ray radiation was a bending magnet that enabled us to work in the photon energy range of 21.21 to 320 eV. The spectrometer was devised to collect 100% of the ions with kinetic energies up to 30 eV. The photoelectron-photoion (PEPICO) and photoelectron-photoion-photoion (PE2PICO) coincidence techniques were used in the present work. RESULTS: The ratio of double-to-total photoionization as a function of the photon energy for the SUVA molecule exhibits remarkably similar behavior with other atomic and molecular systems. SO depends on large excess energy above the ionization threshold, enabling the photoelectron to leave the interaction region rather speedily to yield a sudden change in the Coulomb field that the shaken electron feels. The measured asymptotic SO probability is PSO (∞) = 0.09. CONCLUSIONS: The present analysis shows that the separation of SO and KO processes relies on the experimental evidence that there is no significant interference between SO and KO. The analysis also shows that the separate formulation of KO and SO presents a factual portrayal of double photoionization. Despite having 50 electrons, SUVA has lower double-to-total photoionization fraction (9%) in comparison, for instance, to argon atoms (~20%), which has 18 electrons. This lower e-e correlation could be attributed to its larger volume, that is, lower electron density.

10.
Int J Clin Pract ; 75(10): e14656, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34324769

RESUMO

OBJECTIVES: The study aimed to assess the fidelity of Medication Reconciliation (MR) delivered by the pharmacist at hospital admission and discharge, and the process outcomes. METHODS: Prospective study conducted in cardiology and cardiovascular surgery unit of a university hospital between September 2019 and January 2020. Independent observers collected data to measure MR fidelity, related to coverage, sources of information used to collect medication history and presence of outstanding and resolved Undocumented Discrepancies (UD). Process outcomes included medication errors and their potential to cause harm, identified by the pharmacist during the formal MR process. RESULTS: Of the eligible patients, 122 (69.7%) had their medications reconciled in a timely manner at hospital admission and 50 (43.8%) at discharge. The pharmacist consulted 2.76 (±0.8) sources of information to build the medication history, on average. At least one outstanding UD was found in 101 (82.8%) patients at admission and in 41 (82.0%), at discharge. The average number of outstanding UD per patient at admission and discharge was 3.0 (±2.6) and 2.4 (±1.9), respectively. The UD communicated to the physician by the pharmacist during the formal MR process, involved mainly omission errors and were classified as requiring monitoring or potentially necessary intervention. In the univariate analysis, the number of drugs pre-admission and admission, the reason for admission and non-elective readmission in 30 days were associated with the presence of medication errors at admission. CONCLUSIONS: This study found a high number of UD, suggesting flaws in the implementation of MR and highlight the importance of quality measurement.


Assuntos
Reconciliação de Medicamentos , Alta do Paciente , Hospitais Universitários , Humanos , Admissão do Paciente , Estudos Prospectivos
11.
J Med Internet Res ; 23(1): e18872, 2021 01 11.
Artigo em Inglês | MEDLINE | ID: mdl-33427686

RESUMO

BACKGROUND: The low levels of control of hypertension and diabetes mellitus are a challenge that requires innovative strategies to surpass barriers of low sources, distance, and quality of health care. OBJECTIVE: The aim of this study is to develop a clinical decision support system (CDSS) for diabetes and hypertension management in primary care, to implement it in a resource-constrained region, and to evaluate its usability and health care practitioner satisfaction. METHODS: This mixed methods study is a substudy of HealthRise Brazil Project, a multinational study designed to implement pilot programs to improve screening, diagnosis, management, and control of hypertension and diabetes among underserved communities. Following the identification of gaps in usual care, a team of clinicians established the software functional requirements. Recommendations from evidence-based guidelines were reviewed and organized into a decision algorithm, which bases the CDSS reminders and suggestions. Following pretesting and expert panel assessment, pilot testing was conducted in a quasi-experimental study, which included 34 primary care units of 10 municipalities in a resource-constrained area in Brazil. A Likert-scale questionnaire evaluating perceived feasibility, usability, and utility of the application and professionals' satisfaction was applied after 6 months. In the end-line assessment, 2 focus groups with primary care physicians and nurses were performed. RESULTS: A total of 159 reminders and suggestions were created and implemented for the CDSS. At the 6-month assessment, there were 1939 patients registered in the application database and 2160 consultations were performed by primary care teams. Of the 96 health care professionals who were invited for the usability assessment, 26% (25/96) were physicians, 46% (44/96) were nurses, and 28% (27/96) were other health professionals. The questionnaire included 24 items on impressions of feasibility, usability, utility, and satisfaction, and presented global Cronbach α of .93. As for feasibility, all professionals agreed (median scores of 4 or 5) that the application could be used in primary care settings and it could be easily incorporated in work routines, but physicians claimed that the application might have caused significant delays in daily routines. As for usability, overall evaluation was good and it was claimed that the application was easy to understand and use. All professionals agreed that the application was useful (score 4 or 5) to promote prevention, assist treatment, and might improve patient care, and they were overall satisfied with the application (median scores between 4 and 5). In the end-line assessment, there were 4211 patients (94.82% [3993/4211] with hypertension and 24.41% [1028/4211] with diabetes) registered in the application's database and 7960 consultations were performed by primary health care teams. The 17 participants of the focus groups were consistent to affirm they were very satisfied with the CDSS. CONCLUSIONS: The CDSS was applicable in the context of primary health care settings in low-income regions, with good user satisfaction and potential to improve adherence to evidence-based practices.


Assuntos
Sistemas de Apoio a Decisões Clínicas/normas , Diabetes Mellitus/terapia , Hipertensão/terapia , Adulto , Brasil , Análise de Dados , Feminino , Humanos , Masculino , Projetos Piloto , Inquéritos e Questionários
12.
J Electrocardiol ; 64: 36-41, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33310477

RESUMO

This study aims to assess the prevalence of electrocardiographic abnormalities based on the Minnesota code from a large sample of 1.01 m adult Brazilian primary care patients and to evaluate its association with age, sex, and cardiovascular risk factors. A large electrocardiogram (ECG) database of such patients aged ≥18 years (mean age 52 ± 17 years-old with 60.2% female). was analyzed and the results were stratified by sex and age. The prevalence of abnormalities was more common in men and the elderly population. Major electrocardiographic abnormalities were observed in 20.2% of adults and 43.1% of elderly patients, and minor abnormalities were found in 46.0% 39.4%, respectively. For adult patients, the number and percentage of major abnormalities rise depending on the number of cardiovascular risk factors. For elderly patients, the correlation between these variables is not clear, and the percentage of major abnormalities remains stable independently of the number of risk factors.


Assuntos
Doenças Cardiovasculares , Eletrocardiografia , Adolescente , Adulto , Idoso , Brasil/epidemiologia , Doenças Cardiovasculares/diagnóstico , Doenças Cardiovasculares/epidemiologia , Feminino , Hispânico ou Latino , Humanos , Masculino , Pessoa de Meia-Idade , Minnesota , Prevalência , Atenção Primária à Saúde , Fatores de Risco
13.
Physica A ; 565: 125586, 2021 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-35875202

RESUMO

The world's population suffers a COVID-19 pandemic. By September 2020 nearly 1 million people had died. These are official numbers. The real cases might be much higher, due to under-reporting in many countries. Different strategies were adopted by national governments. Neglecting what was defined by sanitarian authorities, some politicians, at the beginning of the pandemic, declared that it would be a little flu, without consequences, lighter than seasonal flues. Some politicians propagated medicines with no scientific support. In many countries and regions, people became confused. The population's reactions to these political positions may facilitate or block the virus spread. In this paper, we propose a model connecting the spreading of opinions with the propagation of a pandemic. We discuss how conflicting opinions can diffuse in the pandemic environment and the influence it has on the population's behavior; how it may cause a greater or smaller number of infected individuals.

14.
Am J Bot ; 107(1): 31-44, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31916253

RESUMO

PREMISE: Plant mucilages are composed of strongly hydrophilic polysaccharides and contribute to seed germination and seedling establishment. The myxospermic seeds of Magonia pubescens, a Cerrado (neotropical savanna) tree species, produces a voluminous mucilage capsule when hydrated. The development of the mucilaginous layer, the process of mucilage secretion and its role in seed germination was not previously studied so far. METHODS: Morphological, anatomical, histochemical, and ultrastructural evaluations of the seed coat during seed development were undertaken. The formation of the mucilage capsule was followed using scanning electron microscopy, and the coat's effects on seed hydration and germination were evaluated after experimental manipulation of the seed coat. RESULTS: The mucilaginous layer is contained in the outer coat of the seed. The mucilage-secreting cells accumulate proteins in the outer periclinal region and acidic polysaccharides in the inner periclinal region of the periplasmic space. Neutral polysaccharides, which form the loosely organized secondary wall, form a folding, basket-like structure surrounding the acidic polysaccharides. The protoplast collapses at maturity. With hydration, the mucilage expands, breaks the epidermal layer, and forms a mucilage capsule around the seed. The mucilaginous seed coat does not increase the germination rate. CONCLUSIONS: Upon mucilage hydration, the secondary cell walls forming the network of neutral polysaccharides are released, along with proteins, and help retain the acidic polysaccharides-forming a peculiar architecture that imparts integrity and consistency to the mucilage capsule. As winged seeds are not usually buried, the mucilage capsule favors seedling hydration, contributing to its establishment on the soil surface.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Mucilagem Vegetal , Parede Celular , Germinação , Polissacarídeos , Sementes
15.
Microsc Microanal ; 26(3): 609-621, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32495729

RESUMO

Mauritia flexuosa palms inhabit wetland environments in the dry, seasonal Brazilian savanna (Cerrado) and produce mucilaginous secretions in the stem and petiole that have a medicinal value. The present study sought to characterize the chemical natures of those secretions and to describe the anatomical structures involved in their synthesis. Chemical analyzes of the secretions, anatomical, histochemical analyses, and electron microscopy studies were performed on the roots, stipes, petioles, and leaf blades. Stipe and petiole secretions are similar, and rich in cell wall polysaccharides and pectic compounds such as rhamnose, arabinose, xylose, mannose, galactose, and glucose, which are hydrophilic largely due to their hydroxyl and carboxylate groups. Mucilaginous secretions accumulate in the lumens of vessel elements and sclerenchyma fibers of the root, stipe, petiole, and foliar veins; their synthesis involves cell wall loosening and the activities of dictyosomes. The outer faces of the cell walls of the parenchyma tissue in the mesophyll expand to form pockets that rupture and release pectocellulose substances into the intercellular spaces. The presence of mucilage in the xylem, extending from the roots to the leaf veins and continuous with the leaf apoplast, and sub-stomatal chambers suggest a strategy for plant water economy.


Assuntos
Arecaceae/metabolismo , Secreções Corporais/fisiologia , Folhas de Planta/citologia , Polissacarídeos/metabolismo , Áreas Alagadas , Xilema/citologia , Arabinose , Brasil , Parede Celular , Galactose , Glucose , Manose , Folhas de Planta/metabolismo , Raízes de Plantas/citologia , Ramnose , Xilema/metabolismo , Xilose
16.
J Electrocardiol ; 57S: S56-S60, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31653433

RESUMO

BACKGROUND: Left bundle branch block is recognized as a marker of higher risk of death, but the prognostic value of the right bundle branch block in the general population is still controversial. Our aim is to evaluate the risk of overall and cardiovascular mortality in patients with right (RBBB) and left bundle branch block (LBBB) in a large electronic cohort of Brazilian patients. METHODS: This observational retrospective study was developed with the database of digital ECGs from Telehealth Network of Minas Gerais, Brazil (TNMG). All ECGs performed from 2010 to 2017 in primary care patients over 16 years old were assessed. The electronic cohort was obtained by linking data from ECG exams (name, sex, date of birth, city of residence) and those from national mortality information system, using standard probabilistic linkage methods (FRIL: Fine-grained record linkage software, v.2.1.5, Atlanta, GA). Only the first ECG of each patient was considered. Clinical data were self-reported, and ECGs were interpreted manually by cardiologists and automatically by the Glasgow University Interpreter software. Hazard ratio (HR) for mortality was estimated using Cox regression. RESULTS: From a dataset of 1,773,689 patients, 1,558,421 primary care patients over 16 years old underwent a valid ECG recording during 2010 to 2017. We excluded 17,359 patients that didn't have a valid QRS measure from the Glasgow program and 11,091 patients from the control group that had QRS equal or above 120 ms and were not RBBB or LBBB. Therefore, 1,529,971 were included (median age 52 [Q1:38; Q3:65] years; 40.2% were male). In a mean follow-up of 3.7 years, the overall mortality rate was 3.34%. RBBB was more frequent (2.42%) than LBBB (1.32%). In multivariate analysis, adjusting for sex, age and comorbidities, both patients with RBBB (HR 1.32; CI 95% 1.27-1.37) and LBBB (HR 1.69; CI 95% 1.62-1.76) had higher risk of overall mortality. Women with RBBB had an increased risk of all-cause death compared to men (p < 0.001). Cardiovascular mortality was higher in patients with LBBB (HR 1.77; CI 95% 1.55-2.01), but not for RBBB. CONCLUSIONS: Patients with RBBB and LBBB had higher risk of overall mortality. Women with RBBB had more risk of all-cause death than men. LBBB was associated with higher risk of cardiovascular mortality.


Assuntos
Bloqueio de Ramo , Eletrocardiografia , Adolescente , Brasil/epidemiologia , Eletrônica , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos
17.
J Electrocardiol ; 57S: S75-S78, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31526573

RESUMO

Digital electrocardiographs are now widely available and a large number of digital electrocardiograms (ECGs) have been recorded and stored. The present study describes the development and clinical applications of a large database of such digital ECGs, namely the CODE (Clinical Outcomes in Digital Electrocardiology) study. ECGs obtained by the Telehealth Network of Minas Gerais, Brazil, from 2010 to 17, were organized in a structured database. A hierarchical free-text machine learning algorithm recognized specific ECG diagnoses from cardiologist reports. The Glasgow ECG Analysis Program provided Minnesota Codes and automatic diagnostic statements. The presence of a specific ECG abnormality was considered when both automatic and medical diagnosis were concordant; cases of discordance were decided using heuristisc rules and manual review. The ECG database was linked to the national mortality information system using probabilistic linkage methods. From 2,470,424 ECGs, 1,773,689 patients were identified. After excluding the ECGs with technical problems and patients <16 years-old, 1,558,415 patients were studied. High performance measures were obtained using an end-to-end deep neural network trained to detect 6 types of ECG abnormalities, with F1 scores >80% and specificity >99% in an independent test dataset. We also evaluated the risk of mortality associated with the presence of atrial fibrillation (AF), which showed that AF was a strong predictor of cardiovascular mortality and mortality for all causes, with increased risk in women. In conclusion, a large database that comprises all ECGs performed by a large telehealth network can be useful for further developments in the field of digital electrocardiography, clinical cardiology and cardiovascular epidemiology.


Assuntos
Fibrilação Atrial , Eletrocardiografia , Adolescente , Brasil , Feminino , Humanos , Minnesota , Redes Neurais de Computação , Adulto Jovem
18.
Ann Bot ; 122(2): 267-277, 2018 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-29788057

RESUMO

Background and Aims: Palm seeds are interesting models for studying seed reserve mobilization at the tissue level due to the abundance and complexity of reserves stored in their living endosperm cells and the development of a highly specialized haustorium. We studied structural and physiological aspects of the initial phases of reserve mobilization in seeds of a neotropical palm, Butia capitata, and sought to characterize the interactions between the different developmental pathways of the haustorium and endosperm. Methods: Morphological and histochemical evaluations of the haustorium, the endosperm adjacent to the embryo, and the peripheral endosperm of dry, imbibed, dormant seeds and seeds geminating for 2, 5 and 10 d were performed. Biochemical analyses included determinations of endo-ß-mannanase activity, hormonal profiling (20 hormones belonging to eight classes) and H2O2 quantification in various tissues. Key Results: The mobilization of haustorium reserves was associated with germination and involved distinct hormonal alterations in the endosperm related to H2O2 production. The mobilization of endosperm reserves occurred as a post-germination event controlled by the seedling and involved major structural changes in the haustorium, including growth (which increased contact with, and pressure on, the endosperm) and the formation of an aerenchyma (thus facilitating O2 diffusion). The flow of O2 to the endosperm and changes in endogenous contents of H2O2 and hormones (cytokinins, auxins, brassinosteroids and ethylene) induced the establishment of an endosperm digestion zone and the translocation of reserves to the haustorium. Conclusions: The haustorium-endosperm relationship during reserve mobilization plays a pivotal role in signal integration between growth and degradation pathways in germinating seeds of Butia capitata.


Assuntos
Arecaceae/crescimento & desenvolvimento , Peróxido de Hidrogênio/metabolismo , Reguladores de Crescimento de Plantas/metabolismo , Arecaceae/anatomia & histologia , Arecaceae/fisiologia , Transporte Biológico , Brassinosteroides/metabolismo , Citocininas/metabolismo , Endosperma/anatomia & histologia , Endosperma/crescimento & desenvolvimento , Endosperma/fisiologia , Metabolismo Energético , Etilenos/metabolismo , Germinação , Ácidos Indolacéticos/metabolismo , Dormência de Plantas , Plântula/anatomia & histologia , Plântula/crescimento & desenvolvimento , Plântula/fisiologia , Sementes/anatomia & histologia , Sementes/crescimento & desenvolvimento , Sementes/fisiologia
19.
Ann Bot ; 119(3): 353-365, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28028018

RESUMO

BACKGROUND AND AIMS: The underground saxophone stem systems produced by seedlings of certain palm species show peculiar growth patterns and distinctive morphologies, although little information is available concerning their development and function. We studied the ontogenesis of the saxophone stem in Acrocomia aculeata, an important neotropical oleaginous palm, and sought to experimentally define its function. METHODS: Morpho-anatomical evaluations were performed during 240 d on seedlings using traditional methodologies. The tuberous region of the structure was submitted to histochemical tests and evaluated by transmission electron microscopy. The aerial portions of 130 1- to 3-year-old greenhouse plants were removed and their continuous growth capacity was evaluated after 30 d. Severed saxophone stems were also stored at room temperature (average 25 °C) for up to 90 d and then cultured for 60 d to evaluate root and shoot emission. KEY RESULTS: The development of the saxophone stem is distinct from other underground systems previously described, and involves three processes: growth and curvature of the cotyledonary petiole, expansion and curvature of the hypocotyl, and expansion of the plumule internodes. The tuberous region stores water and starch, as well as lesser amounts of mucilage and oil. Growth of the aerial portion occurred in 84 % of the separated saxophone stems and in 53 % of the stems held in storage. CONCLUSIONS: The saxophone stem represents an important adaptation of A. aculeata to anthropogenically impacted and/or dry environments by promoting the burial of both the shoot meristem and storage reserves, which allows the continuous growth of aerial organs.


Assuntos
Arecaceae/crescimento & desenvolvimento , Caules de Planta/crescimento & desenvolvimento , Arecaceae/anatomia & histologia , Arecaceae/fisiologia , Hipocótilo/anatomia & histologia , Hipocótilo/crescimento & desenvolvimento , Hipocótilo/fisiologia , Caules de Planta/anatomia & histologia , Caules de Planta/fisiologia , Tubérculos/anatomia & histologia , Tubérculos/crescimento & desenvolvimento , Tubérculos/fisiologia , Plântula/anatomia & histologia , Plântula/crescimento & desenvolvimento , Plântula/fisiologia
20.
BMC Cardiovasc Disord ; 17(1): 152, 2017 06 13.
Artigo em Inglês | MEDLINE | ID: mdl-28610624

RESUMO

BACKGROUND: Knowledge of the normal limits of the electrocardiogram (ECG) is mandatory for establishing which patients have abnormal ECGs. No studies have assessed the reference standards for a Latin American population. Our aim was to establish the normal ranges of the ECG for pediatric and adult Brazilian primary care patients. METHODS: This retrospective observational study assessed all the consecutive 12-lead digital electrocardiograms of primary care patients at least 1 year old in Minas Gerais state, Brazil, recorded between 2010 and 2015. ECGs were excluded if there were technical problems, selected abnormalities were present or patients with selected self-declared comorbidities or on drug therapy. Only the first ECG from patients with multiple ECGs was accepted. The University of Glasgow ECG analysis program was used to automatically interpret the ECGs. For each variable, the 1st, 2nd, 50th, 98th and 99th percentiles were determined and results were compared to selected studies. RESULTS: A total of 1,493,905 ECGs were recorded. 1,007,891 were excluded and 486.014 were analyzed. This large study provided normal values for heart rate, P, QRS and T frontal axis, P and QRS overall duration, PR and QT overall intervals and QTc corrected by Hodges, Bazett, Fridericia and Framingham formulae. Overall, the results were similar to those from other studies performed in different populations but there were differences in extreme ages and specific measurements. CONCLUSIONS: This study has provided reference values for Latinos of both sexes older than 1 year. Our results are comparable to studies performed in different populations.


Assuntos
Doenças Cardiovasculares/diagnóstico , Mineração de Dados/métodos , Eletrocardiografia/normas , Frequência Cardíaca , Atenção Primária à Saúde , Adolescente , Adulto , Distribuição por Idade , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Brasil/epidemiologia , Doenças Cardiovasculares/epidemiologia , Doenças Cardiovasculares/fisiopatologia , Criança , Pré-Escolar , Bases de Dados Factuais , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Pessoa de Meia-Idade , Reconhecimento Automatizado de Padrão , Valor Preditivo dos Testes , Valores de Referência , Estudos Retrospectivos , Distribuição por Sexo , Fatores Sexuais , Processamento de Sinais Assistido por Computador , Software , Adulto Jovem
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