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OBJECTIVE: To identify the ocular pathologies that are reported as causes of low vision in children. MATERIAL AND METHODS: The systematic search was carried out in Medline (PubMed), Embase and Lilacs. Observational studies with populations between 0-18 years of age, reporting visual acuity data between 20/60-20/400 and reporting the frequency of ocular pathologies were selected. Studies in which the diagnosis of the condition had not been verified by a professional, or which covered only cases of blindness, uncorrected refractive errors, or amblyopia, were excluded. The methodological quality of the articles was evaluated using the Joanna Briggs Institute instrument for prevalence studies. RESULTS: 27 studies conducted in Asia (13 publications), Africa (6 studies), Oceania (4 studies), Europe and South America (2 studies each) were included. The most reported causes of low vision were: cataract, with prevalence between 0.8% and 27.2%; albinism with from 1.1% to 47%; nystagmus, with prevalence between 1.3% and 22%; retinal dystrophies between 3.5% and 50%; retinopathy of prematurity (ROP) with prevalence between 1.1% and 65.8%, optic atrophy between 0.2% and 17.6%, and glaucoma from 2.4% to 18.1%. CONCLUSIONS: Cataract, albinism and nystagmus are the ocular pathologies most mentioned by studies as a cause of low vision in children, as well as retinal diseases such as ROP and optic nerve diseases such as atrophy. However, there are numerous eye conditions that can result in low vision in the pediatric population.
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Catarata , Glaucoma , Nistagmo Patológico , Retinopatia da Prematuridade , Baixa Visão , Recém-Nascido , Humanos , Criança , Baixa Visão/etiologia , Baixa Visão/complicações , Cegueira/etiologia , Glaucoma/complicações , Catarata/complicações , Retinopatia da Prematuridade/complicaçõesRESUMO
Efavirenz (EFV) is a widely used antiretroviral, due to its safety, efficacy, and low cost. However, plasma concentrations have been related with an increased risk of virological failure and the appearance of serious adverse reactions. EFV is metabolized by Cytochrome P450, the main isoenzyme involved is CYP2B6 and the most relevant genetic polymorphisms found in several populations has been the CYP2B6 516G> T. The aim of this study was to identify the frequency of the CYP2B6 516G>T polymorphism and its effect on the plasma concentration of efavirenz (EFV) in a group of people living with HIV (PLWH) and undergoing EFV treatment in Morelos, Mexico. Ninety-six PLWH undergoing EFV treatment, at a daily dose of 600 mg orally in combination with other antiretrovirals (ARVs), were included in this study. The CYP2B6 516G>T polymorphism was detected using PCR-RFLP. The plasma concentrations of EFV were evaluated by high-resolution liquid chromatography coupled to a mass-mass detector, using a protein precipitation method. The median plasma EFV concentration was 4.6 µg/mL (IQR = 4.64) and 64.6% of the subjects had concentrations above the therapeutic range. The CYP2B6 516G>T genotype findings were as follows: 46.9% of the population presented the wild-type genotype (GG), while 45.8 % and 7.3 % showed the heterozygote (GT) and the polymorphic homozygote (TT) genotype, respectively. The homozygote G had the lowest plasma concentrations of EFV (median = 4.1 µg/mL and IQR = 1.7 µg/mL), followed by those with the GT genotype (median = 5.1 µg/mL and IQR = 3.0 µg/mL). Participants with the homozygous T genotype had the highest EFV concentrations (median = 9.7 µg/mL and IQR = 5.8 µg/mL). In conclusion, the CYP2B6 516G>T polymorphism was associated with plasma levels of EFV in PLWH undergoing ARV treatment. EFV plasma concentrations at 600mg doses were outside the therapeutic range in most subjects.
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Fármacos Anti-HIV , Infecções por HIV , HIV-1 , Alcinos , Fármacos Anti-HIV/efeitos adversos , Benzoxazinas , Ciclopropanos , Citocromo P-450 CYP2B6/genética , Genótipo , Infecções por HIV/tratamento farmacológico , Infecções por HIV/genética , HIV-1/genética , Humanos , México , Polimorfismo Genético/genética , Polimorfismo de Nucleotídeo Único/genéticaRESUMO
Introducción: la calidad educativa en las IES (Instituciones de Educación Superior) ha sido avalada por procesos de evaluación y acreditación a nivel institucional y curricular, llevando a cabo un proceso de mejora continua, mediante recomendaciones sugeridas por los evaluadores, lo anterior garantizará la calidad institucional ante la formación de futuros profesionales. Objetivo: analizar las experiencias del profesorado de la carrera de enfermería de la Facultad de Estudios Superiores Iztacala, sobre el cambio curricular vivido. Material y métodos: estudio cualitativo con enfoque fenomenológico, mediante entrevista a profundidad a doce profesores de enfermería. Muestreo por conveniencia de acuerdo a la saturación de datos. En aspectos éticos y legales, se realizó carta de consentimiento informado. El análisis de datos fue basado en Miles y Huberman, con abordaje teórico según Van Manen. Resultados: surgieron dos categorías: 1. Sentimientos y afectaciones emocionales respecto al cambio curricular y laborales; 2. impacto del cambio curricular en los aprendizajes de los estudiantes, las cuales evidenciaron cómo el profesorado ha vivido los cambios curriculares en los 17 años desde que fue implementada la licenciatura. Conclusiones: los informantes narraron que en cada cambio curricular surgen emociones diferentes, entre incertidumbre, compromiso, responsabilidad y asumir empoderamiento para implementar la curricula, con ello, lograr los objetivos esperados por la misma, considerando perfil de egreso y rendimiento académico de los estudiantes.
Introduction: the educational quality at the higher level in schools and faculties has been endorsed by evaluation and accreditation processes at the institutional and curricular level, carrying out an improvement process, through the recommendations suggested by the evaluators, thus covering them in a certain time. The foregoing will guarantee the institutional quality before the training of future professionals. Objective: to analyze experiences of the teaching staff of the nursing career of the Iztacala Faculty of Higher Studies, on the curricular change experienced. Material and methods: Qualitative study with a phenomenological approach, through an in-depth interview with twelve nursing professors. Convenience sampling according to data saturation. In ethical and legal aspects, an informed consent letter was drawn up. The data analysis was through Miles and Huberman, with a theoretical approach based on Van Manen. Results: two categories emerged: 1. Feelings and emotional affectations regarding the curricular and work change; 2. impact of curricular change on student learning, which showed how teachers have experienced curricular changes in the 17 years since the degree was implemented. Conclusions: the informants narrated that in each curricular change different emotions arise, between uncertainty, commitment, responsibility and assuming empowerment to implement the curriculum, thereby achieving the objectives expected by it, considering the graduation profile and the academic performance of the students.
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Humanos , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Idoso , Adulto Jovem , Ensino , Educação em Enfermagem , Inovação Organizacional , Acontecimentos que Mudam a VidaRESUMO
Generation and inadequate management of solid waste constitute a global challenge. Projections for 2050 portend an annual increase of 3.40 billion tons of waste. This study assessed the impact of an environmental education intervention (EEI) aimed at reducing waste generation and fomenting pro-environmental behaviors in an academic public-health institution in Mexico. The EEI was implemented over 20 months using a model of behavior change. Using a mixed-method design (QUAN + qual), baseline and follow-up measurements were performed through electronic questionnaires (n = 754), focus groups (n = 20), and waste quantification. A double-difference model was performed to measure pro-environmental behaviors impact: overall and by sex, age, educational level and function within the institution. Waste quantification was performed using a quartering method and weekly monitoring. The qualitative data were studied through thematic analysis. As a result of the EEI, women reduced their use of multilayer packaging (-15.6 pp, p < 0.05) and frequent use of non-ecological materials (-17.6 pp, p < 0.05). Graduate-level participants reduced their regular and frequent use of these materials (-33.3 pp, p < 0.05, 27.6 pp, p < 0.01), while those with lower educational levels increased their ecological behavior at home (12.1 pp, p < 0.05). Waste generation dropped by 60.1% vis-a-vis the baseline measurement. Our qualitative findings showed a relationship between holding a position of power in the institution and recycling. They also revealed that available infrastructure for separating waste contributed substantially to the observed impact. With actions centered on physical structure, community practice and institutional policy components, the EEI improved the pro-environmental behaviors and perceptions of participants.
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Reciclagem , Gerenciamento de Resíduos , Feminino , Humanos , México , Embalagem de Produtos , Resíduos Sólidos , Inquéritos e QuestionáriosRESUMO
In this paper we report on the influence of polysaccharides' molecular structure on the antibacterial activity and cytotoxicity of composites based on silver nanoparticles (AgNPs) immobilized into carboxymethyl-cellulose (CMC). These composites were green synthesized from the reduction of silver ions into aqueous solutions of the polysaccharide, using CMC with different degree of substitution (DS) and molecular weight (Mw). The composites were characterized by transmission electron microscopy (TEM), as well as infrared (ATR-FTIR), ultraviolet (UV-Vis), Raman, and X-ray photo-electron (XPS) spectroscopic techniques. The antibacterial activity was evaluated with minimum inhibitory concentration against Enterococcus faecalis. The cytotoxicity of composites was assessed against human gingival fibroblast. Experimental evidence suggests that particle size distribution and morphology of AgNPs change according to the quantity of silver precursor added to the reaction, as well as the DS and Mw of CMC used for composites preparation. This is related to the dispersion of silver precursor into aqueous solutions of the polysaccharide and the formation of Ag-O coordination bonds among AgNPs and COO- moieties of CMC. Moreover, these coordination bonds modify the ability of nanoparticles to produce and release Ag+ into aqueous dispersion, adjusting their antibacterial activity and the induction of cytotoxicity into the tested biological environments.
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INTRODUCTION: Lung cancer (LC) is the most common tumour, and the leading cause of cancer-related death worldwide. Although cases of choroidal metastasis and cancer-associated retinopathy have been reported in LC, no studies have been conducted on the Mexican population to describe retinochoroidal findings during the course of LC, and the relationship with its stage. OBJECTIVE: To evaluate patients with a diagnosis of LC, and to describe the posterior segment findings in relationship to the stage of LC. MATERIALS AND METHODS: A cross-sectional and descriptive study was conducted on 50 patients with LC (100 eyes). The demographic data included age, gender, histological type, evolution time, stage, treatment, and comorbidities. The measurement variables included visual acuity (LogMAR), anterior segment biomicroscopy, retinal photography, fluorescein retinal angiography, optical coherence tomography, and electroretinogram. All patients were evaluated by two ophthalmologists. RESULTS: The study included a total of 26 men and 24 women, with a mean age of 65 years, and a mean time from LC diagnosis of 6 months. The principal histological type was adenocarcinoma (70%), and most (50%) were in stage II at the time of evaluation, with 15 (30%) patients having a metastasis (stage IV). The changes in the posterior segment included choroidal metastasis (16%), retinal metastasis (10%), cancer-associated retinopathy (6%), and vascular occlusions (4%). The majority of patients who presented with posterior segment alterations were in stage IV. CONCLUSIONS: Vascular occlusions, cancer-associated retinopathy, choroidal and retinal metastases may be found in LC, with an incidence higher than that reported in the literature, especially in advanced stages of LC, although they can be found from stage II in asymptomatic patients.
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Neoplasias da Coroide/secundário , Neoplasias Pulmonares/patologia , Neoplasias da Retina/secundário , Idoso , Neoplasias da Coroide/diagnóstico por imagem , Estudos Transversais , Feminino , Humanos , Masculino , México , Pessoa de Meia-Idade , Neoplasias da Retina/diagnóstico por imagemRESUMO
OBJECTIVES: To evaluate the diagnostic performance of 18F-choline PETCT in staging prostate cancer (PC) and whether the use of this imaging modality changes the therapeutic decision in patients previously staged by conventional imaging. The secondary aim was to determine the prognostic factors associated with positive choline PETCT findings in both detection of disseminated disease and in changes in the therapeutic indication. MATERIALS AND METHODS: Multicentre, retrospective, observational study of 269 patients diagnosed with PC. Mean age was 69 ± 9.2 years. Of the 269 patients, 62 (23%) had high-risk localized PC (group 1), 118 (43.9%) biochemical failure after radical prostatectomy (group 2), and 89 (33.1%) biochemical failure after radiotherapy (group 3). None of the patients showed clear evidence of distant disease on computed tomography or bone scans. The following potential prognostic factors were assessed: PSA level at diagnosis; primary and secondary Gleason; Gleason score (GS); clinical and pathologic T and N stage; number of positive cylinders in the biopsy; presence of vascular or lymphatic invasion; status of surgical margins; androgen deprivation therapy (ADT); time to biochemical recurrence; and PSA, PSA doubling time (PSADT), and PSA velocity (PSAV) at failure. Univariate and multivariate analyses were performed, and receiver-operating curves calculated. RESULTS: The mean PSA by groups was, group 1: 31.22 ng/ml, group 2: 2.52 ng/ml and group 3: 5.85 ng/ml. The tumor detection rate with 18F-choline PETCT was 74% (group 1: 85.5%, group 2: 55.1% and group 3: 91%). Prognostic factors for positive 18F-choline PETCT were identified only in group 2: PSA at failure and PSADT. 18F-choline PETCT changed the therapeutic indication in 62.8% (group 1: 71%, group 2: 55.2% and group 3: 70.1%). The prognostic factors for a change in treatment were identified only in group 1: secondary Gleason ≤ 4 and GS ≤ 7 and in group 2: PSA at failure, PSA nadir after surgery and pathologic stage N0. 18F-choline PETCT identified lymph node and/or metastatic disease in 32.7% (group 1: 25.8%, group 2: 29.7% and group 3: 41.6%). Prognostic factors for detecting lymph node/metastasis were identified in the group 2: PSA failure ≥ 1.37 ng/ml and PSADT < 4 months and in the group 3: PSADT < 4.6 months and time to failure < 5 years. CONCLUSION: These findings support the clinical use de 18F-choline PET-CT in staging high-risk patients with a secondary Gleason ≤ 4 and GS ≤ 7, in restaging patients with biochemical recurrence after RP if PSA at failure ≥ 1.37 ng/ml or PSADT ≤ 4 months and in patients with biochemical failure after RT, if PSADT ≤ 4.6 months and time to failure < 5 years, because it determines a change in the therapeutic indication.
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Colina/metabolismo , Radioisótopos de Flúor/metabolismo , Recidiva Local de Neoplasia/diagnóstico , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada/métodos , Prostatectomia , Neoplasias da Próstata/diagnóstico , Idoso , Seguimentos , Humanos , Masculino , Gradação de Tumores , Recidiva Local de Neoplasia/diagnóstico por imagem , Recidiva Local de Neoplasia/metabolismo , Recidiva Local de Neoplasia/cirurgia , Estadiamento de Neoplasias , Neoplasias da Próstata/diagnóstico por imagem , Neoplasias da Próstata/cirurgia , Curva ROC , Compostos Radiofarmacêuticos/metabolismo , Estudos RetrospectivosRESUMO
Individuals with Parkinson's disease (PD) suffer from motor and mental disturbances due to degeneration of dopaminergic and non-dopaminergic neuronal systems. Although they provide temporary symptom relief, current treatments fail to control motor and non-motor alterations or to arrest disease progression. Aiming to explore safety and possible motor and neuropsychological benefits of a novel strategy to improve the PD condition, a case series study was designed for brain grafting of human neural progenitor cells (NPCs) to a group of eight patients with moderate PD. A NPC line, expressing Oct-4 and Sox-2, was manufactured and characterized. Using stereotactic surgery, NPC suspensions were bilaterally injected into patients' dorsal putamina. Cyclosporine A was given for 10 days prior to surgery and continued for 1 month thereafter. Neurological, neuropsychological, and brain imaging evaluations were performed pre-operatively, 1, 2, and 4 years post-surgery. Seven of eight patients have completed 4-year follow-up. The procedure proved to be safe, with no immune responses against the transplant, and no adverse effects. One year after cell grafting, all but one of the seven patients completing the study showed various degrees of motor improvement, and five of them showed better response to medication. PET imaging showed a trend toward enhanced midbrain dopaminergic activity. By their 4-year evaluation, improvements somewhat decreased but remained better than at baseline. Neuropsychological changes were minor, if at all. The intervention appears to be safe. At 4 years post-transplantation we report that undifferentiated NPCs can be delivered safely by stereotaxis to both putamina of patients with PD without causing adverse effects. In 6/7 patients in OFF condition improvement in UPDRS III was observed. PET functional scans suggest enhanced putaminal dopaminergic neurotransmission that could correlate with improved motor function, and better response to L-DOPA. Patients' neuropsychological scores were unaffected by grafting. Trial Registration: Fetal derived stem cells for Parkinson's disease https://doi.org/10.1186/ISRCTN39104513Reg#ISRCTN39104513.
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Mesencéfalo , Células-Tronco Neurais , Doença de Parkinson , Putamen , Adolescente , Adulto , Idoso , Aloenxertos , Dopamina/metabolismo , Feminino , Seguimentos , Humanos , Masculino , Mesencéfalo/metabolismo , Mesencéfalo/patologia , Mesencéfalo/cirurgia , Pessoa de Meia-Idade , Células-Tronco Neurais/metabolismo , Células-Tronco Neurais/patologia , Células-Tronco Neurais/transplante , Doença de Parkinson/metabolismo , Doença de Parkinson/patologia , Doença de Parkinson/cirurgia , Putamen/metabolismo , Putamen/patologia , Putamen/cirurgiaRESUMO
In this paper, the synthesis of magnetic nanofibrous materials with a soft ferromagnetic response based on magnetite nanoparticles (SMON) loaded to aqueous carboxymethyl-cellulose (CMC)/polyvinyl-alcohol (PVA) polymeric blends is reported. The nanofibrous materials were obtained from the electrospinning of SMON-CMC/PVA blends with different SMON content, applying a constant tension of 15 kV. The synthesized samples were analyzed by transmission electron microscopy, scanning electron microscopy, attenuated total reflectance Fourier transform infrared, Raman and X-Ray photoelectron spectroscopy, as well as static magnetic measuring. Our experimental findings indicate that nanofibers' diameter decreases as SMON content in the electrospun polymeric blends is increased, since these magnetic nanoparticles diminish the interactions between PVA and CMC molecules, which improves their spinnability. Moreover, the spatial distribution of SMON in the fibers provides to the synthesized nanofibrous materials a novel soft ferromagnetic response at room temperature. This phenomenon is attributed to the formation of nanoparticles' aggregates that are discretely distributed in the nanofibers.
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Calcium phosphate cement has been widely investigated as a bone graft substitute due to its excellent self-setting ability, biocompatibility, osteoconductivity and moldability. In addition, mesoporous materials have been studied as potential materials for application in medical devices due to their large surface area, which is capable of loading numerous biological molecules, besides being bioactive. In this study, bone ß-TCP-MCPM-based injectable cement with mesoporous silica particles was synthesized and characterized in terms of its mechanical properties, microstructure, porosity, injectability, in vitro bioactivity and degradability; together with toxicity effects in CHO-K1 cell culture. The results showed that the ß-TCP-MCPM cement is bioactive after soaking in simulated body fluid solution, and mesoporous silica particles provided better physicochemical properties compared with silica-free cement. Toxicity assays showed low CHO-K1 cell viability after treatment with more concentrated extracts (200 mg ml-1). However, this behavior did not compromise the reproductive capacity and did not promote significant DNA damage in those cells. In conclusion, the ß-TCP-MCPM cement associated with mesoporous silica might be considered as a potential bone substitute for the repair and regeneration of bone defects.
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Cimentos Ósseos/química , Regeneração Óssea/efeitos dos fármacos , Substitutos Ósseos/química , Fosfatos de Cálcio/química , Dióxido de Silício/química , Animais , Líquidos Corporais , Cimentos Ósseos/toxicidade , Células CHO , Ensaio Cometa , Cricetinae , Cricetulus , Dano ao DNA , Injeções , Teste de Materiais , Testes para Micronúcleos , Porosidade , Regeneração , Estresse MecânicoRESUMO
BACKGROUND: In recent years, Copper-64 (T1/2 = 12.7 h) in the chemical form of copper dichloride ([64Cu]CuCl2) has been identified as a potential agent for PET imaging and radionuclide therapy targeting the human copper transporter 1, which is overexpressed in a variety of cancer cells. Limited human biodistribution and radiation dosimetry data is available for this tracer. The aim of this research was to determine the biodistribution and estimate the radiation dosimetry of [64Cu]CuCl2, using whole-body (WB) PET scans in healthy volunteers. Six healthy volunteers were included in this study (3 women and 3 men, mean age ± SD, 54.3 ± 8.6 years; mean weight ± SD, 77.2 ± 12.4 kg). After intravenous injection of the tracer (4.0 MBq/kg), three consecutive WB emission scans were acquired at 5, 30, and 60 min after injection. Additional scans were acquired at 5, 9, and 24 h post-injection. Low-dose CT scan without contrast was used for anatomic localization and attenuation correction. OLINDA/EXM software was used to calculate human radiation doses using the reference adult model. RESULTS: The highest uptake was in the liver, followed by lower and upper large intestine walls, and pancreas, in descending order. Urinary excretion was negligible. The critical organ was liver with a mean absorbed dose of 310 ± 67 µGy/MBq for men and 421 ± 56 µGy/MBq for women, while the mean WB effective doses were 51.2 ± 3.0 and 61.8 ± 5.2 µSv/MBq for men and women, respectively. CONCLUSIONS: To the best of our knowledge, this is the first report on biodistribution and radiation dosimetry of [64Cu]CuCl2 in healthy volunteers. Measured absorbed doses and effective doses are higher than previously reported doses estimated with biodistribution data from patients with prostate cancer, a difference that could be explained not just due to altered biodistribution in cancer patients compared to healthy volunteers but most likely due to the differences in the analysis technique and assumptions in the dose calculation.
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This study was developed based on in vivo investigation of microporous granular biomaterials based on calcium phosphates, involving matrices of ß-tricalcium phosphate (ß-TCP), hydroxyapatite (HA), biphasic compositions of both phases and a control group. The physicochemical characterization of materials was carried out by X-Ray diffraction (DRX) and mercury porosimetry. Biodegradability, bioactivity and neoformation processes were investigated by Raman spectroscopy, scanning electron microscopy (SEM) and polarized light conducted on biopsies obtained from in vivo tests for periods of 90 and 180 days. These were performed to evaluate the behavior of granular microporous compositions in relation to bone neoformation. Through the performance obtained from in vivo assays, excellent osseointegration and bone tissue neoformation were observed. The results are encouraging and show that the microporous granular biomaterials of HA, ß-TCP and biphasic compositions show similar results with perfect osseointegration. Architectures simulating a bone structure can make the difference between biomaterials for bone tissue replacement and repair.
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Materiais Biocompatíveis/farmacologia , Fosfatos de Cálcio/farmacologia , Osteogênese/efeitos dos fármacos , Animais , Materiais Biocompatíveis/química , Fosfatos de Cálcio/química , Fêmur/efeitos dos fármacos , Fêmur/crescimento & desenvolvimento , Porosidade , CoelhosRESUMO
Introducción: La práctica clínica es un elemento medular en la formación de los profesionales de enfermería, así, el aprendizaje del cuidado está estructurado por un proceso individual, influenciado por el contexto que cada sujeto vive y el entorno que lo determina. Objetivo: Determinar el sentido y la importancia pedagógica de los fenómenos educativos vividos cotidianamente por los estudiantes en el aprendizaje del cuidado obstétrico a partir de las experiencias en la práctica clínica. Método: Estudio cualitativo-descriptivo, enfoque fenomenológico, interpretativo. Se realizaron 8 entrevistas a profundidad, a estudiantes de 7.o semestre de la Licenciatura en Enfermería y Obstetricia. Se empleó análisis temático de contenido, se señalan conceptos significativos y se asignan identificadores para generar categorías. Validación de resultados a través de criterios de credibilidad, confirmabilidad, transferibilidad y confiabilidad. Resultados: El estudio del cotidiano del estudiante de enfermería en el aprendizaje del cuidado a la gestante permitió reconocer como categoría «Praxis en el aprendizaje¼, con 2 subcategorías: a) Construcción del saber en la práctica para la transformación y b) Manteniendo motivación, iniciativa y confianza. El individuo construye el conocimiento a partir de la interacción con el entorno físico y social, donde pone en juego el desarrollo de sus capacidades cognitivas mediante la aplicación y el reajuste de sus propios esquemas cognitivos y de aplicación de destrezas. Conclusiones: El deseo por aprender algo lleva a las personas a procurar y adquirir conocimientos, habilidades, actitudes o valores que más tarde le permitirán desarrollarlas en diversos ámbitos. El impulso e interés por aprender sobre determinada temática que llame particularmente la atención o sea placentera será el motor que conduzca a profundizar en la búsqueda de conocimientos y/o mayores habilidades con resultados ampliamente satisfactorios.
Introduction: Clinical practice is a modular element within the formation of nursing professionals, and this care learning is structured through an individual process which is influenced by the specific context and its determinants. Objective: To determine the sense and pedagogical importance of the educational phenomena lived by students in their obstetric care learning process. Method: This is a qualitative-descriptive study with a phenomenological and interpretative focus. Eight in-depth interviews were performed on students of the seventh semester of a Baccalaureate in Nursing and Obstetrics program. Topic-content analysis was used. Significant concepts were pointed out, and diverse identifiers were assigned to different categories. The validation of the results is founded on the criteria of credibility, confirmability, transferability, and trustworthiness. Results: The exploration of nursing students in their pregnant women care learning process allowed us to acknowledge a ''Praxis at Learning'' category with 2 sub-categories: a) building of knowledge in the transformation practice; and b) maintenance of motivation, initiative, and confidence. Indeed, the individual builds knowledge from the interaction with the physical and social surrounding; where he/she applies and adjusts his/her cognitive capacities and skills. Conclusions: The desire for learning drives persons to procure acquiring knowledge, skills, and values which they will eventually put into practice in diverse environments. The impulse and interest for learning on a specific area of interest will be the motivation to deepen into the pleasure of acquiring more knowledge and skills.
Introdução: A prática clínica é um elemento medular na formação dos profissionais de enfermagem, assim, a aprendizagem do cuidado está estruturada por um processo individual, influenciado pelo contexto que cada sujeito vive e o ambiente que o determina. Objetivo: Determinar o sentido e a importância pedagógica dos fenómenos educativos vividos cotidianamente pelos estudantes na aprendizagem do cuidado obstétrico a partir de experiências na prática clínica. Método: Estudo qualitativo-descritivo, abordagem fenomenológica, interpretativa. Realizaram-se oito entrevistas a profundidade a estudantes do sétimo semestre da Licenciatura em Enfermagem e Obstetrícia. Realizou-se análise temática de conteúdo, assinalaram-se conceitos significativos e atribuíram-se identificadores para gerar categorias. Validação de resultados a través de critérios de credibilidade confirmabilidade, transferibilidade e confiabilidade. Resultados: O estudo do cotidiano do estudante de enfermagem na aprendizagem do cuidado à gestante permitiu reconhecer como categoria ''Práxis na aprendizagem'', com duas sub-categorias: a) Construção do saber na prática para a transformação e b) Mantendo motivação, iniciativa e confiança. O indivíduo constrói o conhecimento a partir da interação com o ambiente físico e social, onde põe em jogo o desenvolvimento de suas capacidades cognitivas a través da aplicação e o reajuste de seus próprios esquemas cognitivos de aplicação de competências. Conclusões: O desejo por aprender algo leva às pessoas a procurar adquirir conhecimentos, habilidades, atitudes ou valores que mais tarde permitirão desenvolvê-las em diversos âmbitos. O impulso e interesse por aprender sobre determinada temática que chame particularmente a atenção, quer dizer, prazeroso; será o motor que conduz a aprofundar na busca de conhecimentos e/o maiores habilidades com resultados amplamente satisfatórios.
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Humanos , Masculino , Feminino , Adulto , Preceptoria , Estudantes de Enfermagem , Aprendizagem , ObstetríciaRESUMO
In this work an experimental investigation was carried out to study the effect that positron range has over positron emission tomography (PET) scans through measurements of the line spread function (LSF) in tissue-equivalent materials. Line-sources consisted of thin capillary tubes filled with (18)F, (13)N or (68)Ga water-solution inserted along the axis of symmetry of cylindrical phantoms constructed with the tissue-equivalent materials: lung (inhale and exhale), adipose tissue, solid water, trabecular and cortical bone. PET scans were performed with a commercial small-animal PET scanner and image reconstruction was carried out with filtered-backprojection. Line-source distributions were analyzed using radial profiles taken on axial slices from which the spatial resolution was determined through the full-width at half-maximum, tenth-maximum, twentieth-maximum and fiftieth-maximum. A double-Gaussian model of the LSFs was used to fit experimental data which can be incorporated into iterative reconstruction methods. In addition, the maximum activity concentration in the line-sources was determined from reconstructed images and compared to the known values for each case. The experimental data indicates that positron range in different materials has a strong effect on both spatial resolution and activity concentration quantification in PET scans. Consequently, extra care should be taken when computing standard-uptake values in PET scans, in particular when the radiopharmaceutical is taken up by different tissues in the body, and more even so with high-energy positron emitters.
Assuntos
Processamento de Imagem Assistida por Computador/métodos , Imagens de Fantasmas , Tomografia por Emissão de Pósitrons/métodos , Compostos Radiofarmacêuticos/farmacocinética , Tecido Adiposo/diagnóstico por imagem , Animais , Osso Esponjoso/diagnóstico por imagem , Osso Cortical/diagnóstico por imagem , Elétrons , Pulmão/diagnóstico por imagem , Distribuição Tecidual , Água/químicaRESUMO
Information about genetic parameters is essential for selection decisions and genetic evaluation. These estimates are population specific; however, there are few studies with dairy cattle populations reared under tropical and sub-tropical conditions. Thus, the aim was to obtain estimates of heritability and genetic correlations for milk yield and quality traits using pedigree and genomic information from a Holstein population maintained in a tropical environment. Phenotypic records (n = 36 457) of 4203 cows as well as the genotypes for 57 368 single nucleotide polymorphisms from 755 of these cows were used. Covariance components were estimated using the restricted maximum likelihood method under a mixed animal model, considering a pedigree-based relationship matrix or a combined pedigree-genomic matrix. High heritabilities (around 0.30) were estimated for lactose and protein content in milk whereas moderate values (between 0.19 and 0.26) were obtained for percentages of fat, saturated fatty acids and palmitic acid in milk. Genetic correlations ranging from -0.38 to -0.13 were determined between milk yield and composition traits. The smaller estimates compared to other similar studies can be due to poor environmental conditions, which may reduce genetic variability. These results highlight the importance in using genetic parameters estimated in the population under evaluation for selection decisions.
Assuntos
Bovinos/classificação , Bovinos/genética , Ácidos Graxos/análise , Leite/química , Animais , Bovinos/fisiologia , Clima , Feminino , Genótipo , Leite/economia , Linhagem , Polimorfismo de Nucleotídeo ÚnicoRESUMO
In this contribution a novel green chemistry approach for the synthesis of nanofibrous materials based on blends of carboxymethyl-cellulose (CMC)-silver nanoparticles (AgNPs) composite and polyvinyl-alcohol (PVA) is proposed. These nanofibrous materials were obtained from the electrospinning of blends of aqueous solutions of CMC-AgNPs composite and PVA, which were prepared at different CMC/PVA weight ratios in order to electrospin nanofibers applying a constant tension of 15kV. The synthesized materials were characterized by means of transmission electron microscopy, scanning electron microscopy; as well as Fourier-transform infrared, ultraviolet and Raman spectroscopic techniques. Experimental evidence suggests that the diameter of the nanofibers is thinner than any other reported in the literature regarding the electrospinning of CMC. This feature is related to the interactions of AgNPs with carboxyl functional groups of the CMC, which diminish those between the later and acetyl groups of PVA.
Assuntos
Carboximetilcelulose Sódica/química , Química Verde , Nanofibras/química , Nanotecnologia , Prata/química , Técnicas de Química Sintética , Nanopartículas Metálicas/química , Modelos Moleculares , Conformação Molecular , Álcool de Polivinil/químicaRESUMO
O estudo foi conduzido com o objetivo de estimar o custo de produção de animais com diferentes proporções de genes da raca holandesa e a rentabilidade anual por vaca em rebanho no Norte de Minas Gerais por meio de simulação. Foram utilizadas as informações do arquivo zootécnico da Fazenda Queluz, situada em Francisco Sá, MG, Brasil, durante o período de 2007 a 2012. O sistema de produção da fazenda consiste de vacas cruzadas Holandês x Zebu (HZ), de composições genéticas variando de 1/4 HZ até 7/8 HZ. A receita total por animal, rentabilidade anual por vaca e variação da rentabilidade foram estimadas no decorrer dos anos, de acordo com a composição genética. As vacas 7/8 HZ apresentaram maior receita com a produção de leite, mas a rentabilidade estimada foi 7,75% da receita total, seguida pelas vacas 3/4 HZ, que também mostraram 4,11% de rentabilidade. Por outro lado, os animais 3/8 HZ tiveram a maior rentabilidade, seguida pelos animais 1/4 HZ e 1/2 HZ. No decorrer dos anos observou-se inversão da composição genética do rebanho. Em 2007, 64% das vacas do rebanho eram 7/8 HZ, e em 2012 os animais 7/8 HZ foram substituídos por animais 1/4 HZ, 3/8 HZ e 1/2 HZ, perfazendo o total de 90% dos genótipos. Apesar da maior produção dos animais com maior proporção de genes da raça holandesa, observou que a mudança do rebanho para vacas com maior proporção de genes de raças zebuínas leiteiras proporcionou aumento da rentabilidade, fato que pode ser atribuído a maior eficiência econômica deste genótipo...(AU)
A simulation study was conducted to estimate the production costs of animals with different proportions of Holstein genes and annual return per cow in a herd from the northern region of Minas Gerais. Data from the zootechnical archive of Fazenda Queluz, Francisco Sá, MG, Brazil, comprising the period from 2007 to 2012 were used. The production system consists of crossbred Holstein x Zebu (HZ) cows with a genetic composition ranging from 1/4 HZ to 7/8 HZ. Total revenue per animal, annual profit per cow and variation in profitability were estimated over the years according to genetic composition. The revenue from milk production was greater for 7/8 HZ cows, but the estimated annual profit per cow was only 7.75% of total revenue, followed by 3/4 HZ cows which also exhibited low profit (4.11%). The highest profit was observed for 3/8 HZ cows, followed by 1/4 HZ and 1/2 HZ animals. Inversion of the genetic composition of the herd was observed over the years. In 2007, 64% of cows of the herd were 7/8 HZ, while in 2012, 7/8 HZ cows had been replaced with 1/4 HZ, 3/8 HZ and 1/2 HZ animals, accounting for 90% of all genotypes. Despite the greater production of animals with a higher proportion of Holstein genes, the change to cows with a higher proportion of genes of dairy Zebu breeds increased profitability, a fact that might be attributed to the greater economic efficiency of this genotype...(AU)
Assuntos
Animais , Feminino , Bovinos , Indústria Agropecuária , Leite , Custos e Análise de Custo/economia , Bovinos/classificaçãoRESUMO
O estudo foi conduzido com o objetivo de estimar o custo de produção de animais com diferentes proporções de genes da raca holandesa e a rentabilidade anual por vaca em rebanho no Norte de Minas Gerais por meio de simulação. Foram utilizadas as informações do arquivo zootécnico da Fazenda Queluz, situada em Francisco Sá, MG, Brasil, durante o período de 2007 a 2012. O sistema de produção da fazenda consiste de vacas cruzadas Holandês x Zebu (HZ), de composições genéticas variando de 1/4 HZ até 7/8 HZ. A receita total por animal, rentabilidade anual por vaca e variação da rentabilidade foram estimadas no decorrer dos anos, de acordo com a composição genética. As vacas 7/8 HZ apresentaram maior receita com a produção de leite, mas a rentabilidade estimada foi 7,75% da receita total, seguida pelas vacas 3/4 HZ, que também mostraram 4,11% de rentabilidade. Por outro lado, os animais 3/8 HZ tiveram a maior rentabilidade, seguida pelos animais 1/4 HZ e 1/2 HZ. No decorrer dos anos observou-se inversão da composição genética do rebanho. Em 2007, 64% das vacas do rebanho eram 7/8 HZ, e em 2012 os animais 7/8 HZ foram substituídos por animais 1/4 HZ, 3/8 HZ e 1/2 HZ, perfazendo o total de 90% dos genótipos. Apesar da maior produção dos animais com maior proporção de genes da raça holandesa, observou que a mudança do rebanho para vacas com maior proporção de genes de raças zebuínas leiteiras proporcionou aumento da rentabilidade, fato que pode ser atribuído a maior eficiência econômica deste genótipo...
A simulation study was conducted to estimate the production costs of animals with different proportions of Holstein genes and annual return per cow in a herd from the northern region of Minas Gerais. Data from the zootechnical archive of Fazenda Queluz, Francisco Sá, MG, Brazil, comprising the period from 2007 to 2012 were used. The production system consists of crossbred Holstein x Zebu (HZ) cows with a genetic composition ranging from 1/4 HZ to 7/8 HZ. Total revenue per animal, annual profit per cow and variation in profitability were estimated over the years according to genetic composition. The revenue from milk production was greater for 7/8 HZ cows, but the estimated annual profit per cow was only 7.75% of total revenue, followed by 3/4 HZ cows which also exhibited low profit (4.11%). The highest profit was observed for 3/8 HZ cows, followed by 1/4 HZ and 1/2 HZ animals. Inversion of the genetic composition of the herd was observed over the years. In 2007, 64% of cows of the herd were 7/8 HZ, while in 2012, 7/8 HZ cows had been replaced with 1/4 HZ, 3/8 HZ and 1/2 HZ animals, accounting for 90% of all genotypes. Despite the greater production of animals with a higher proportion of Holstein genes, the change to cows with a higher proportion of genes of dairy Zebu breeds increased profitability, a fact that might be attributed to the greater economic efficiency of this genotype...
Assuntos
Feminino , Animais , Bovinos , Custos e Análise de Custo/economia , Indústria Agropecuária , Leite , Bovinos/classificaçãoRESUMO
The aim of the study was to examine the changes in milk fatty acid (FA) profile of grazing buffaloes fed either low (L, 276g/d) or high (H, 572g/d) doses of a blend (70:30, wt/wt) of soybean and linseed oils. Fourteen multiparous Mediterranean buffaloes grazing on a native pasture were fed 4 kg/day of a commercial concentrate containing no supplemental oil over a pre-experimental period of ten days. The baseline milk production and composition and milk FA profile were measured over the last three days. After this pre-experimental period the animals received the same concentrate added with either the L or H oil doses for 26 additional days. Milk yield (g/animal/day) did not differ at the start (1776 ± 522 and 1662 ± 291 for L and H, respectively, P<0.622) or at the end of the trial (4590 ± 991 and 4847 ± 447 in L and H, respectively, P<0.543). Baseline milk fat content (g/kg) averaged 77.1 (±20.5) in L and 74.3 (±9.9) in H (P<0.10) and was reduced (P<0.031) to 60.7 (±23.6) and 49.4 (±11.2) (P<0.0031) respectively after L and H with no differences between treatments (P<0.277). Baseline milk protein content (L=43.2 ± 3.4 and H= 44.3 ± 6.9g/kg) increased after oil supplementation (P<0.0001) in both L (73.2 ± 6.0g/kg) and H (68.4 ± 4.9g/kg) without differences between oil doses (P<0.123). Milk fat content of 14:0 decreased after oil supplementation only in the H treatment (5.29 to 4.03, P<0.007) whereas that of 16:0 was reduced (P<0.001) at both L (24.49 to 19.75g/100g FA) and H (25.92 to 19.17g/100g FA) doses. The reduction of total content of 12:0 to 16:0 was higher (P<0.052) in H (32.02 to 23.93g/100g FA) than L (30.17 to 25.45g/100g FA). Vaccenic acid content increased (P<0.001) from 5.70 to 13.24g/100g FA in L and from 5.25 to 16.77 in H, with higher results in the in H treatment (P<0.001). Baseline rumenic acid was sharply increased (P<0.001) in L (1.80 to 4.09g/100g FA, +127%) and H (1.60 to 4.61g/100g FA, +187%) with no differences between...
O objetivo do presente estudo foi avaliar as mudanças no perfil de ácidos graxos do leite de búfalas leiteiras recebendo baixas (B, 276g/d) ou altas (A, 572g/d) doses de uma mistura de óleos de soja e linhaça (70:30, peso/peso) na dieta. Quatorze búfalas multíparas da raça Mediterrânea, mantidas em pastagens nativas, receberam 4kg/dia de um concentrado comercial sem adição de óleo (pré-tratamento) ao longo de umperíodopré-experimental de 10 dias. A produção de leiteindividual e amostras de leite foram coletadas individualmente para determinação dos valores basais de composição e perfil de ácidos graxos do leite nos últimos trêsdias. Após este período, os animais receberam o mesmo concentrado adicionado deBou Apor 26 dias. A produção de leite (g/animal/dia) não diferiu no início (1776 ± 522 e 1662 ± 291para B e A, respectivamente (P<0,622) e no final do período experimental(4590 ±991e4847 ± 447 para LeH, respectivamente, P<0,543). O teor de gordura do leite (g/100g) apresentou valores médios de 77,1(±20,5)paraBe74,3 (±9,9)paraA(P<0,10) durante o período pré-tratamento,mas foi reduzido (P<0,03) após o fornecimento das dietas com óleo para 60,7 (± 23,6) e 49,4 (± 11,2), respectivamente para B e A, não havendo diferenças entre tratamentos (P<0,277). Os teores basais de proteína do leite (B=43,2 ± 3,4 e A=44,3 ± 6,9g/kg) aumentaram após a suplementação com óleo (P<0,0001) em ambos B (73,2 ± 6,0g/kg) e A (68,4 ± 4,9g/kg), não ocorrendo diferenças entre tratamentos (P<0,123). O teor médio basal de 14:0 na gordura do leite (4,76g/100g AG) foi reduzido após a suplementação da dieta com óleo somente no tratamento A (5,29 para 4,03, P<0,007). O teor de 16:0 na gordura do leite foi reduzido (P<0,001) nos tratamentos B (24,49 para 19,75g/100g AG) e A (25,92 para 19,17g/100g AG). A redução nos teores de 12:0+14:0+16:0 na gordura do leite foi maior (P<0,052) em A (32,02 para 23,93g/100g AG) do que em B (30,17 para 25,45g/100g AG). O teor de ácido vacênico (AV)...