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1.
Eur J Nutr ; 62(5): 2245-2256, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37079158

RESUMEN

PURPOSE: Iodine deficiency disorder (IDD) is an ongoing worldwide recognized problem with over two billion individuals having insufficient iodine intake. School-aged children and pregnant women are often target groups for epidemiological studies, but there is a lack of knowledge on the general adult population. The aim of this study was to assess the iodine status among a Portuguese public university staff as a proxy for the adult working population. METHODS: The population study covered 103 adults within the iMC Salt randomized clinical trial, aged 24-69 years. Urinary iodine concentration was measured spectrophotometrically using the Sandell-Kolthoff reaction. Iodine food intake was assessed using a 24-h dietary recall. The contribution of discretionary salt to the iodine daily intake was assessed through 24-h urinary sodium excretion (UIE) and potentiometric iodine determination of household salt. RESULTS: The mean urine volume in 24 h was 1.5 L. The median daily iodine intake estimated from 24-h UIE was 113 µg/day, being lower among women (p < 0.05). Only 22% of participants showed iodine intake above the WHO-recommended cutoff (150 µg/day). The median daily iodine intake estimated from the 24-h dietary recall was 58 µg/day (51 and 68 µg/day in women and men, respectively). Dairy, including yoghurt and milk products, were the primary dietary iodine source (55%). Iodine intake estimated from 24-h UIE and 24-h dietary recall was moderately correlated (Spearman rank correlation coefficient r = 0.34, p < 0.05). The average iodine concentration in household salt was 14 mg I/kg, with 45% of the samples below the minimum threshold preconized by WHO (15 mg I/kg). The contribution of discretionary salt to the daily iodine intake was around 38%. CONCLUSION: This study contributes new knowledge about iodine status in Portuguese working adults. The results revealed moderate iodine deficiency, particularly in women. Public health strategies and monitoring programs are needed to ensure iodine adequacy in all population groups.


Asunto(s)
Yodo , Desnutrición , Masculino , Adulto , Niño , Humanos , Femenino , Embarazo , Animales , Portugal/epidemiología , Universidades , Estado Nutricional , Cloruro de Sodio Dietético , Leche/química
2.
Zygote ; 31(3): 253-265, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-36938666

RESUMEN

Here we report a quantitative analysis of human metaphase II (MII) oocytes from a 22-year-old oocyte donor, retrieved after ovarian-controlled hyperstimulation. Five surplus donor oocytes were processed for transmission electron microscopy (TEM), and a stereological analysis was used to quantify the distribution of organelles, using the point-counting technique with an adequate stereological grid. Comparisons between means of the relative volumes (Vv) occupied by organelles in the three oocyte regions, cortex (C), subcortex (SC) and inner cytoplasm (IC), followed the Kruskal-Wallis test and Mann-Whitney U-test with Bonferroni correction. Life cell imaging and TEM analysis confirmed donor oocyte nuclear maturity. Results showed that the most abundant organelles were smooth endoplasmic reticulum (SER) elements (26.8%) and mitochondria (5.49%). Significant differences between oocyte regions were found for lysosomes (P = 0.003), cortical vesicles (P = 0.002) and large SER vesicles (P = 0.009). These results were quantitatively compared with previous results using prophase I (GV) and metaphase I (MI) immature oocytes. In donor MII oocytes there was a normal presence of cortical vesicles, SER tubules, SER small, medium and large vesicles, lysosomes and mitochondria. However, donor MII oocytes displayed signs of cytoplasmic immaturity, namely the presence of dictyosomes, present in GV oocytes and rare in MI oocytes, of SER very large vesicles, characteristic of GV oocytes, and the rarity of SER tubular aggregates. Results therefore indicate that the criterion of nuclear maturity used for donor oocyte selection does not always correspond to cytoplasmic maturity, which can partially explain implantation failures with the use of donor oocytes.


Asunto(s)
Mitocondrias , Oocitos , Humanos , Adulto Joven , Adulto , Oocitos/metabolismo , Citoplasma , Oogénesis , Núcleo Celular
3.
Fish Physiol Biochem ; 49(4): 577-584, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37204544

RESUMEN

The trade of aquarium organisms is growing worldwide. This market depends on a continuous supply of healthy and colorful aquatic animals, but this sector has few initiatives. However, in the last decade, there has been a growing interest in researching captive breeding of these animals, aiming to develop a more sustainable aquarium hobby. Larviculture is an important phase in the cultivation process because the larvae are more sensitive to stress and variations in the bulk of variables, such as temperature, salinity, nutritional management, light intensity and spectrum, and environmental background colors. Because background color could be a promoter variable of proper welfare, we tested whether it affects the endocrine response of tomato clownfish Amphiprion frenatus larvae to an acute stress challenge. We show that background color influences the endocrine stress axis responsiveness in tomato clownfish. When fish were subjected to a standard acute stressor of 61 days after hatching, only fish adapted to white walls increased the whole-body cortisol levels. From the results presented herein, we recommend that white tanks be avoided for A. frenatus larviculture. Both, the less stress level and the good welfare condition of larvae reared in colored tanks may have robust, practical applications since almost all clownfish in the ornamental aquarium trade come from captive breeding.


Asunto(s)
Perciformes , Solanum lycopersicum , Animales , Fitomejoramiento , Perciformes/fisiología , Peces , Larva
4.
Langmuir ; 36(21): 6007-6016, 2020 06 02.
Artículo en Inglés | MEDLINE | ID: mdl-32369370

RESUMEN

Compared to the canonical sphingoid backbone of sphingolipids (SLs), atypical long-chain bases (LCBs) lack C1-OH (1-deoxy-LCBs) or C1-CH2OH (1-deoxymethyl-LCBs). In addition, when unsaturated, they present a cis-double bond instead of the canonical  Δ4-5 trans-double bond. These atypical LCBs are directly correlated with the development and progression of hereditary sensory and autonomic neuropathy type 1 and diabetes type II through yet unknown mechanisms. Changes in membrane properties have been linked to the biological actions of SLs. However, little is known about the influence of the LCB structure, particularly 1-deoxy(methyl)-LCB, on lipid-lipid interactions and their effect on membrane properties. To address this question, we used complementary fluorescence-based methodologies to study membrane model systems containing POPC and the different LCBs of interest. Our results show that 1-deoxymethyl-LCBs have the highest ability to reduce the fluidity of the membrane, while the intermolecular interactions of 1-deoxy-LCBs were found to be weaker, leading to the formation of less-ordered domains compared to their canonical counterparts-sphinganine and sphingosine. Furthermore, while the presence of a trans-double bond at the Δ4-5 position of the LCB increased the fluidity of the membrane compared to a saturated LCB, a cis-double bond completely disrupted the ability of the LCB to segregate into ordered domains. In conclusion, even small changes on the structure of the LCB, as seen in 1-deoxy(methyl)-LCBs, strongly affects lipid-lipid interactions and membrane fluidity. These results provide evidence that altered balance between species with different LCBs affect membrane properties and may contribute to the pathobiological role of these lipids.

5.
Biochim Biophys Acta Rev Cancer ; 1868(1): 132-147, 2017 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-28341420

RESUMEN

Central nervous system metastases have been reported in 15-25% of breast cancer patients, and the incidence is increasing. Moreover, the survival of these patients is generally poor, with reports of a 1-year survival rate of 20%. Therefore, a better knowledge about the determinants of brain metastasization is essential for the improvement of the clinical outcomes. Here, we summarize the current data about the metastatic cascade, ranging from the output of cancer cells from the primary tumour to their colonization in the brain, which involves the epithelial-mesenchymal transition, invasion of mammary tissue, intravasation into circulation, and homing into and extravasation towards the brain. The phenotypic change in malignant cells, and the importance of the microenvironment in the formation of brain metastases are also inspected. Finally, the importance of genetic and epigenetic changes, and the recently disclosed effects of microRNAs in brain metastasization of breast cancer are highlighted.


Asunto(s)
Neoplasias Encefálicas/patología , Encéfalo/patología , Neoplasias de la Mama/patología , Metástasis de la Neoplasia/patología , Transición Epitelial-Mesenquimal/fisiología , Femenino , Humanos , Tasa de Supervivencia
6.
J Appl Clin Med Phys ; 21(7): 107-118, 2020 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-32363800

RESUMEN

PURPOSE: Multiple metrics are proposed to characterize and compare the complexity of helical tomotherapy (HT) plans created for different treatment sites. METHODS: A cohort composed of 208 HT plans from head and neck (105), prostate (51) and brain (52) tumor sites was considered. For each plan, 14 complexity metrics were calculated. Those metrics evaluate the percentage of leaves with small opening times or approaching the projection duration, the percentage of closed leaves, the amount of tongue-and-groove effect, and the overall modulation of the planned sinogram. To enable data visualization, an approach based on principal component analysis was followed to reduce the dataset dimensionality. This allowed the calculation of a global plan complexity score. The correlation between plan complexity and pretreatment verification results using the Spearman's rank correlation coefficients was investigated. RESULTS: According to the global score, the most complex plans were the head and neck tumor cases, followed by the prostate and brain lesions irradiated with stereotactic technique. For almost all individual metrics, head and neck plans confirmed to be the plans with the highest complexity. Nevertheless, prostate cases had the highest percentage of leaves with an opening time approaching the projection duration, whereas the stereotactic brain plans had the highest percentage of closed leaves per projection. Significant correlations between some of the metrics and the pretreatment verification results were identified for the stereotactic brain group. CONCLUSIONS: The proposed metrics and the global score demonstrated to be useful to characterize and quantify the complexity of HT plans of different treatment sites. The reported differences inter- and intra-group may be valuable to guide the planning process aiming at reducing uncertainties and harmonize planning strategies.


Asunto(s)
Neoplasias de Cabeza y Cuello , Radioterapia de Intensidad Modulada , Cabeza , Neoplasias de Cabeza y Cuello/radioterapia , Humanos , Masculino , Cuello , Dosificación Radioterapéutica , Planificación de la Radioterapia Asistida por Computador
7.
Arch Toxicol ; 93(6): 1649-1664, 2019 06.
Artículo en Inglés | MEDLINE | ID: mdl-30993381

RESUMEN

Brain susceptibility to a neurotoxic insult may be increased in a compromised health status, such as metabolic syndrome. Both metabolic syndrome and exposure to trimethyltin (TMT) are known to promote neurodegeneration. In combination the two factors may elicit additive or compensatory/regulatory mechanisms. Combined effects of TMT exposure (0.5-1 µM) and mimicked metabolic syndrome-through modulation of insulin and glucocorticoid (GC) levels-were investigated in three models: tridimensional rat brain cell cultures for neuron-glia effects; murine microglial cell line BV-2 for a mechanistic analysis of microglial reactivity; and db/db mice as an in vivo model of metabolic syndrome. In 3D cultures, low insulin condition significantly exacerbated TMT's effect on GABAergic neurons and promoted TMT-induced neuroinflammation, with increased expression of cytokines and of the regulator of intracellular GC activity, 11ß-hydroxysteroid dehydrogenase 1 (11ß-Hsd1). Microglial reactivity increased upon TMT exposure in medium combining low insulin and high GC. These results were corroborated in BV-2 microglial cells where lack of insulin exacerbated the TMT-induced increase in 11ß-Hsd1 expression. Furthermore, TMT-induced microglial reactivity seems to depend on mineralocorticoid receptor activation. In diabetic BKS db mice, a discrete exacerbation of TMT neurotoxic effects on GABAergic neurons was observed, together with an increase of interleukin-6 (IL-6) and of basal 11ß-Hsd1 expression as compared to controls. These results suggest only minor additive effects of the two brain insults, neurotoxicant TMT exposure and metabolic syndrome conditions, where 11ß-Hsd1 appears to play a key role in the regulation of neuroinflammation and of its protective or neurodegenerative consequences.


Asunto(s)
Glucocorticoides/metabolismo , Inflamación/metabolismo , Secreción de Insulina/efectos de los fármacos , Degeneración Nerviosa/metabolismo , Compuestos de Trimetilestaño/toxicidad , 11-beta-Hidroxiesteroide Deshidrogenasa de Tipo 1/biosíntesis , 11-beta-Hidroxiesteroide Deshidrogenasa de Tipo 1/efectos de los fármacos , Animales , Línea Celular , Células Cultivadas , Citocinas/biosíntesis , Técnicas In Vitro , Inflamación/inducido químicamente , Síndrome Metabólico/metabolismo , Ratones , Ratones Endogámicos , Degeneración Nerviosa/inducido químicamente , Neuroglía/efectos de los fármacos , Neuronas/efectos de los fármacos , Ratas , Ratas Sprague-Dawley , Receptores de Glucocorticoides/efectos de los fármacos , Reproducibilidad de los Resultados
9.
Foodborne Pathog Dis ; 13(11): 633-641, 2016 11.
Artículo en Inglés | MEDLINE | ID: mdl-27768382

RESUMEN

The increase in prevalence of Salmonella 1,4,[5],12:i:- related infections over the last few years has been considered a public health issue in many European countries, especially as this serovar may be associated with tetraresistance to ampicillin, streptomycin, sulfonamides, and tetracyclines (R-type ASSuT). Salmonella 1,4,[5],12:i:- isolates (n = 187) obtained by the Portuguese National Laboratory from different sources, including human clinical cases (n = 170), veterinary (n = 10), environmental (n = 6), and food samples (n = 1), were collected from 15 districts between 2006 and 2011. All isolates were serotyped using the slide agglutination method and results were confirmed by multiplex PCR for the monophasic variant. From the confirmed Salmonella 1,4,[5],12:i:-, R-type ASSuT isolates were selected by disc diffusion and minimal inhibitory concentration (MIC) determination for further characterization by pulsed-field gel electrophoresis restriction with XbaI, virulence genes determination by PCR, additional antimicrobial resistance profiling by disc diffusion, and epidemiological distribution evaluation. Out of the 187 serotyped isolates, 133 were confirmed as Salmonella 1,4,[5],12:i:- with a R-type ASSuT occurrence of 61.7%. Distribution among Portuguese districts showed a higher percentage of reported cases in coastal areas, in particular, in Porto (24.8%), Setúbal (13.5%), and Aveiro (12.8%), probably due to the higher population density. Clonality analysis revealed a high diversity of pulsotypes with the majority of human salmonellosis cases being attributed to sporadic events. All isolates harbored 14 out of the 18 virulence genes evaluated and 87.8% of the isolates showed all the resistance genes frequently associated with the European clone, blaTEM+sul2+straA-straB+tetB+. This study shows that Salmonella 1,4,[5],12:i:- resistant isolates are widely distributed in Portugal. This may be related to a selective advantage offered by R-type ASSuT profile, the presence of multiple virulent features, including the ability to form biofilms, which along with a high diversity of pulsotypes may be responsible for the dissemination through the country.


Asunto(s)
Contaminación de Alimentos , Microbiología de Alimentos , Salmonelosis Animal/microbiología , Infecciones por Salmonella/microbiología , Salmonella/aislamiento & purificación , Enfermedades de los Porcinos/microbiología , Microbiología del Agua , Animales , Antibacterianos/farmacología , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Biopelículas/crecimiento & desarrollo , Farmacorresistencia Bacteriana Múltiple , Heces/microbiología , Humanos , Incidencia , Ganglios Linfáticos/microbiología , Pruebas de Sensibilidad Microbiana/veterinaria , Tipificación Molecular/veterinaria , Vigilancia de la Población , Portugal/epidemiología , Salmonella/clasificación , Salmonella/efectos de los fármacos , Salmonella/fisiología , Infecciones por Salmonella/epidemiología , Análisis Espacio-Temporal , Sus scrofa , Porcinos , Factores de Virulencia/genética , Factores de Virulencia/metabolismo , Calidad del Agua
10.
BMC Pediatr ; 15: 60, 2015 May 17.
Artículo en Inglés | MEDLINE | ID: mdl-25982707

RESUMEN

BACKGROUND: Data from studies assessing the intake of potassium, and the concomitant sodium-to-potassium ratio are limited. The aim of this study was to evaluate potassium and sodium-to-potassium ratio intake in 8-10 year-old children. METHODS: A cross-sectional survey was carried out from January to June 2014 and data from 163 children (81 boys) were included. Potassium intake was estimated by 24-h urine collection and coefficient of creatinine was used to validate completeness of urine collections. Urinary sodium and sodium-to-potassium ratio were also analysed. A 24-h dietary recall was used to provide information on dietary sources of potassium. Height and weight were measured according to international standards. RESULTS: The mean urinary potassium excretion was 1701 ± 594 mg/day in boys, and 1682 ± 541 mg/day in girls (p = 0.835); 8.0% of children met the WHO recommendations for potassium intake. The mean sodium excretion was 2935 ± 1075 mg/day in boys and 2381 ± 1045 mg/day in girls (p <0.001) and urinary sodium-to-potassium ratio was 3.2 ± 1.4 in boys, and 2.5 ± 1.1 in girls (p = 0.002). The mean fruit and vegetable intake was 353.1 ± 232.5 g/day in boys, and 290.8 ± 213.1 g/day in girls (p = 0.101). CONCLUSIONS: This study reported a low compliance of potassium intake recommendations in 8-10 year-old children. Health promotion interventions are needed in order to broaden public awareness of potassium inadequacy and to increase potassium intake.


Asunto(s)
Conducta Alimentaria , Potasio/orina , Índice de Masa Corporal , Niño , Creatinina/orina , Estudios Transversales , Escolaridad , Ingestión de Energía , Femenino , Frutas , Humanos , Masculino , Actividad Motora , Padres , Portugal , Sodio/orina , Sodio en la Dieta , Encuestas y Cuestionarios , Verduras
11.
Rev Gaucha Enferm ; 35(2): 47-52, 2014 Jun.
Artículo en Portugués | MEDLINE | ID: mdl-25158460

RESUMEN

Social-historical study aimed at discussing the nursing and psychiatric nurse models, from the discourses published in the Annals of Nursing.The historical sources were articles published in the Annals of Nursing journal, from 1933 to 1951. An analysis of the discourse was subsidized by the genealogy of power by Michel Foucault.The analysis showed that the discourse on nursing and the psychiatric nurse, in the first half of the 20th century, is set, on one side, by the propositions used by psychiatrists, who sought to reiterate stereotypes and vocations to practice nursing, and, on the other side, by the active participation of nurses seeking to legitimize expertise for psychiatric nursing. It was concluded that the discourses analyzed defined a psychiatric care focused on the nurse and not the rest of the nursing staff, at that time.


Asunto(s)
Modelos de Enfermería , Publicaciones Periódicas como Asunto/historia , Enfermería Psiquiátrica/historia , Edición/historia , Historia del Siglo XX
12.
Biochim Biophys Acta Mol Cell Biol Lipids ; 1869(3): 159462, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38307322

RESUMEN

In eukaryotes, the de novo synthesis of sphingolipids (SLs) consists of multiple sequential steps which are compartmentalized between the endoplasmic reticulum and the Golgi apparatus. Studies over many decades have identified the enzymes in the pathway, their localization, topology and an array of regulatory mechanisms. However, little is known about the evolutionary forces that underly the generation of this complex pathway or of its anteome, i.e., the metabolic pathways that converge on the SL biosynthetic pathway and are essential for its activity. After briefly describing the pathway, we discuss the mechanisms by which the enzymes of the SL biosynthetic pathway are targeted to their different subcellular locations, how the pathway per se may have evolved, including its compartmentalization, and the relationship of the pathway to eukaryogenesis. We discuss the circular interdependence of the evolution of the SL pathway, and comment on whether current Darwinian evolutionary models are able to provide genuine mechanistic insight into how the pathway came into being.


Asunto(s)
Vías Biosintéticas , Esfingolípidos , Esfingolípidos/metabolismo , Redes y Vías Metabólicas , Eucariontes/metabolismo , Retículo Endoplásmico/metabolismo
13.
Rev Bras Enferm ; 77(1): e20230217, 2024.
Artículo en Inglés, Portugués | MEDLINE | ID: mdl-38511789

RESUMEN

OBJECTIVES: to analyze the role of nursing in the establishment of an HIV/AIDS Testing and Counseling Center in a Brazilian municipality. METHODS: a historical study utilizing primary sources, including documents and oral accounts, involving a total of ten participants. The study encompasses the years 1997 and 1998. The research took place at the Testing and Counseling Center in São João de Meriti. Data was collected from March to May 2022. RESULTS: nursing made significant contributions through the development of training initiatives led by nurses, who were also responsible for individual and group counseling, as well as HIV testing requests. FINAL CONSIDERATIONS: nursing played a crucial role in the center and in the management of Sexually Transmitted Infections, being involved in all stages of treatment in accordance with current public health policy.


Asunto(s)
Infecciones por VIH , Enfermedades de Transmisión Sexual , Humanos , Infecciones por VIH/diagnóstico , Consejo , Prueba de VIH , Brasil
14.
Nutrients ; 16(12)2024 Jun 19.
Artículo en Inglés | MEDLINE | ID: mdl-38931305

RESUMEN

BACKGROUND: Handgrip strength (HGS) is an indicator of muscular strength, used in the diagnosis of sarcopenia, undernutrition, and physical frailty as well as recovery. Typically, the maximum HGS value is used; however, recent evidence suggests the exploration of new indicators provided based on the force-time curve to achieve a more comprehensive assessment of muscle function. Therefore, the objective was to identify indicators of the HGS profile beyond maximum HGS, based on force-time curves, and to systematize knowledge about their applications to various types of samples, health issues, and physical performance. METHODS: A systematic review was performed including studies whose participants' HGS was assessed with a digital or adapted dynamometer. The outcome measures were HGS profile indicators calculated from the force-time curve. RESULTS: a total of 15 studies were included, and the following indicators were identified: grip fatigue, fatigability index, fatigue rate, fatigue resistance, time to 80% maximal voluntary contraction, plateau coefficient of variability, time to maximum value, T-90%, release rate, power factor, grip work, average integrated area, endurance, cycle duration, time between cycles, maximum and minimum force-velocity, rate of grip force, final force, inflection point, integrated area, submaximal control, and response time. CONCLUSIONS: Various indicators based on the force-time curve can be assessed through digital or adapted dynamometers. Future research should analyze these indicators to understand their implications for muscle function assessment, to standardize evaluation procedures, to identify clinically relevant measures, and to clarify their implications in clinical practice.


Asunto(s)
Fuerza de la Mano , Dinamómetro de Fuerza Muscular , Humanos , Fuerza de la Mano/fisiología , Femenino , Masculino , Fatiga Muscular/fisiología , Anciano , Músculo Esquelético/fisiología , Fuerza Muscular , Persona de Mediana Edad , Sarcopenia/diagnóstico , Sarcopenia/fisiopatología , Factores de Tiempo , Adulto
15.
Prog Lipid Res ; 92: 101253, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37659458

RESUMEN

The unique biophysical and biochemical properties of lipids render them crucial in most models of the origin of life (OoL). Many studies have attempted to delineate the prebiotic pathways by which lipids were formed, how micelles and vesicles were generated, and how these micelles and vesicles became selectively permeable towards the chemical precursors required to initiate and support biochemistry and inheritance. Our analysis of a number of such studies highlights the extremely narrow and limited range of conditions by which an experiment is considered to have successfully modeled a role for lipids in an OoL experiment. This is in line with a recent proposal that bias is introduced into OoL studies by the extent and the kind of human intervention. It is self-evident that OoL studies can only be performed by human intervention, and we now discuss the possibility that some assumptions and simplifications inherent in such experimental approaches do not permit determination of mechanistic insight into the roles of lipids in the OoL. With these limitations in mind, we suggest that more nuanced experimental approaches than those currently pursued may be required to elucidate the generation and function of lipids, micelles and vesicles in the OoL.


Asunto(s)
Lípidos , Micelas , Humanos , Lípidos/química
16.
Appl Radiat Isot ; 202: 111066, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37865066

RESUMEN

This study aims to report the relevant issues concerning small fields in the commissioning of a TrueBeam STx for photon energies of 6MV, 10MV, 6FFF, and 10FFF. Percent depth doses, profiles, and field output factors were measured according to the beam model configuration of the treatment planning system. Multiple detectors were used based on the IAEA TRS-483 protocol as well as EBT3 radiochromic film. Analytical Anisotropic and Acuros XB algorithms, were configured and validated through basic dosimetry comparisons and end-to-end clinical tests.


Asunto(s)
Radiometría , Planificación de la Radioterapia Asistida por Computador , Planificación de la Radioterapia Asistida por Computador/métodos , Radiometría/métodos , Algoritmos , Fotones/uso terapéutico , Carmustina
17.
Artículo en Inglés | MEDLINE | ID: mdl-37271251

RESUMEN

Lipid droplets (LD) are important regulators of lipid metabolism and are implicated in several diseases. However, the mechanisms underlying the roles of LD in cell pathophysiology remain elusive. Hence, new approaches that enable better characterization of LD are essential. This study establishes that Laurdan, a widely used fluorescent probe, can be used to label, quantify, and characterize changes in cell LD properties. Using lipid mixtures containing artificial LD we show that Laurdan GP depends on LD composition. Accordingly, enrichment in cholesterol esters (CE) shifts Laurdan GP from ∼0.60 to ∼0.70. Moreover, live-cell confocal microscopy shows that cells present multiple LD populations with distinctive biophysical features. The hydrophobicity and fraction of each LD population are cell type dependent and change differently in response to nutrient imbalance, cell density, and upon inhibition of LD biogenesis. The results show that cellular stress caused by increased cell density and nutrient overload increased the number of LD and their hydrophobicity and contributed to the formation of LD with very high GP values, likely enriched in CE. In contrast, nutrient deprivation was accompanied by decreased LD hydrophobicity and alterations in cell plasma membrane properties. In addition, we show that cancer cells present highly hydrophobic LD, compatible with a CE enrichment of these organelles. The distinct biophysical properties of LD contribute to the diversity of these organelles, suggesting that the specific alterations in their properties might be one of the mechanisms triggering LD pathophysiological actions and/or be related to the different mechanisms underlying LD metabolism.


Asunto(s)
Lauratos , Gotas Lipídicas , Gotas Lipídicas/metabolismo , Lauratos/análisis , Lauratos/metabolismo , Metabolismo de los Lípidos , 2-Naftilamina/análisis , 2-Naftilamina/metabolismo
18.
Front Med (Lausanne) ; 10: 1247660, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37915322

RESUMEN

Regardless of the benefits of fall prevention programs, people with Parkinson's disease (PD) will still fall. Therefore, it is crucial to explore novel therapeutic approaches that are well-accepted and effective for addressing fall risk and the fear of falls among this population. The present study aims to assess the feasibility of the Landing Wise program as a therapeutic intervention for reducing the fear of falling in people with PD. A mixed-methods study will be conducted using convenience sampling to recruit 20 people with PD with a moderate concern of falling from a Parkinson's Patients Association. In addition to usual care, participants will attend 2 days per week, 90 min group sessions for 8 weeks. The intervention combines group cognitive behavioral intervention with the training of safe landing strategies. Feasibility will be assessed by six key domains (recruitment strategy and rates, enrollment, retention, acceptability, reasons for decline/withdrawal, and adverse events). Quantitative data will be analyzed using descriptive statistics to characterize the sample, followed by inferential statistics to evaluate differences in the Short Falls Efficacy Scale-International Scale, Movement Disorder Society Unified Parkinson's Disease Rating Scale, Timed Up Go, 6-Minutes Walking Distance, and fall frequency and severity scores between baseline and final assessment. Qualitative data will be analyzed using an inductive thematic analysis process. There is a growing interest in developing new effective therapeutic approaches for people with PD. If proven program feasibility, this study precedes a randomized controlled trial to establish the effectiveness of the Landing Wise program.

19.
Rev Bras Enferm ; 76(1): e20220180, 2023.
Artículo en Inglés, Portugués | MEDLINE | ID: mdl-36888753

RESUMEN

OBJECTIVE: to analyze the professional struggles between nursing organizational entities, in Rio de Janeiro, during the Regional Nursing Council's electoral process (1990-1993 administration). METHOD: historical study. We used journalistic articles, normative documents, legislation and semi-structured interviews with five nursing professionals who participated in this process. Interpretation of findings was supported by Bourdieu's concepts of habitus, field, capital, and symbolic power. RESULTS: Electoral Code changes of the aforementioned council, under the influence of administration (1987-1990), candidate for re-election, influenced the disclosure and eligibility criteria, making it difficult for broad participation, especially of Associação Brasileira de Enfermagem Rio de Janeiro Section. FINAL CONSIDERATIONS: nursing, in this period, generated a field of disputes related to positions of power and gender, which was evidenced in the electoral process studied, which highlighted using limiting strategies by a group, making it difficult for the entire category to participate.


Asunto(s)
Política , Humanos , Brasil
20.
Occup Environ Med ; 69(7): 514-8, 2012 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-22539658

RESUMEN

OBJECTIVES: As part of smoking surveillance, the authors conducted an epidemiologic investigation in southern Brazil to identify the occurrence of Green Tobacco Sickness and risk factors for illness and to recommend control and prevention measures. METHODS: A 1:2 case-control study matched by subjects' smoking habits. The study population was residents of Candelária, Rio Grande do Sul state, who farm tobacco and provided a urine sample for cotinine measurement by high-performance liquid chromatography. Confirmed cases were persons with compatible clinical presentation (headache, nausea, vomit, dizziness or weakness) and cotinine level >10 ng/ml. Controls were persons without compatible signs or symptoms. The association measure was the matched OR with 95% CIs and p<0.05. RESULTS: Of 33 confirmed cases, 64% were men, average age was 33 years (SD ± 11.8 years) and 57% were landowners. Cases have had similar illness in the past and were likelier to be workers hired by farmers-landowners than controls. Multivariate analysis yielded independent association between these variables and illness, controlled for age and sex. Contact with pesticides and working with wet tobacco leaves were not associated with illness. CONCLUSIONS: The authors confirmed Green Tobacco Sickness in southern Brazil; the authors recommend investigation of its prevalence in tobacco-growing regions and monitoring of and education about the disease and its prevention by occupational health authorities.


Asunto(s)
Enfermedades de los Trabajadores Agrícolas/etiología , Nicotiana/química , Nicotina/efectos adversos , Exposición Profesional/efectos adversos , Adulto , Enfermedades de los Trabajadores Agrícolas/epidemiología , Enfermedades de los Trabajadores Agrícolas/orina , Brasil/epidemiología , Estudios de Casos y Controles , Cotinina/orina , Femenino , Humanos , Incidencia , Masculino , Análisis Multivariante , Propiedad , Hojas de la Planta/química , Factores de Riesgo , Factores Sexuales , Fumar/orina , Adulto Joven
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