Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 90
Filtrar
1.
Mol Phylogenet Evol ; 195: 108046, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38447924

RESUMEN

The global decline of freshwater mussels and their crucial ecological services highlight the need to understand their phylogeny, phylogeography and patterns of genetic diversity to guide conservation efforts. Such knowledge is urgently needed for Unio crassus, a highly imperilled species originally widespread throughout Europe and southwest Asia. Recent studies have resurrected several species from synonymy based on mitochondrial data, revealing U. crassus to be a complex of cryptic species. To address long-standing taxonomic uncertainties hindering effective conservation, we integrate morphometric, phylogenetic, and phylogeographic analyses to examine species diversity within the U. crassus complex across its entire range. Phylogenetic analyses were performed using cytochrome c oxidase subunit I (815 specimens from 182 populations) and, for selected specimens, whole mitogenome sequences and Anchored Hybrid Enrichment (AHE) data on âˆ¼ 600 nuclear loci. Mito-nuclear discordance was detected, consistent with mitochondrial DNA gene flow between some species during the Pliocene and Pleistocene. Fossil-calibrated phylogenies based on AHE data support a Mediterranean origin for the U. crassus complex in the Early Miocene. The results of our integrative approach support 12 species in the group: the previously recognised Unio bruguierianus, Unio carneus, Unio crassus, Unio damascensis, Unio ionicus, Unio sesirmensis, and Unio tumidiformis, and the reinstatement of five nominal taxa: Unio desectusstat. rev., Unio gontieriistat. rev., Unio mardinensisstat. rev., Unio nanusstat. rev., and Unio vicariusstat. rev. Morphometric analyses of shell contours reveal important morphospace overlaps among these species, highlighting cryptic, but geographically structured, diversity. The distribution, taxonomy, phylogeography, and conservation of each species are succinctly described.


Asunto(s)
Unio , Animales , Filogenia , Filogeografía , Unio/genética , Europa (Continente) , ADN Mitocondrial/genética , Variación Genética
2.
Braz J Med Biol Res ; 57: e13066, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38265342

RESUMEN

Health literacy (HL) is defined as a cognitive and social skill that determines the motivation and ability of individuals to understand and use information to promote and maintain proper health. Inadequate HL has been associated with worse outcomes in diabetes control, poor self-care, and higher hospitalization rates for some chronic diseases. We hypothesized that HL influences the prevalence of diabetic retinopathy (DR) among individuals with type 2 diabetes mellitus (T2DM) and that inadequate glycemic control would mediate this association. This was a cross-sectional study carried out with 288 participants of the "Brazilian Diabetes Study" cohort. Inclusion criteria were people diagnosed with T2DM aged between 40 and 70 years and ability to read and write. In the adequate HL group, DR was found in 16.5% of participants and in the inadequate HL group, it was found in 32.8% (P=0.0081). Individuals with inadequate HL had a higher risk of having DR, and this association was still statistically significant after adjusting for HbA1c, low-density lipoprotein cholesterol, systolic blood pressure, and diastolic blood pressure. In conclusion, HL is related to DR without the mediation of classical clinical variables.


Asunto(s)
Diabetes Mellitus Tipo 2 , Retinopatía Diabética , Alfabetización en Salud , Humanos , Adulto , Persona de Mediana Edad , Anciano , Estudios Transversales , Brasil
3.
Braz. j. med. biol. res ; 57: e13066, 2024. tab
Artículo en Inglés | LILACS-Express | LILACS | ID: biblio-1528103

RESUMEN

Health literacy (HL) is defined as a cognitive and social skill that determines the motivation and ability of individuals to understand and use information to promote and maintain proper health. Inadequate HL has been associated with worse outcomes in diabetes control, poor self-care, and higher hospitalization rates for some chronic diseases. We hypothesized that HL influences the prevalence of diabetic retinopathy (DR) among individuals with type 2 diabetes mellitus (T2DM) and that inadequate glycemic control would mediate this association. This was a cross-sectional study carried out with 288 participants of the "Brazilian Diabetes Study" cohort. Inclusion criteria were people diagnosed with T2DM aged between 40 and 70 years and ability to read and write. In the adequate HL group, DR was found in 16.5% of participants and in the inadequate HL group, it was found in 32.8% (P=0.0081). Individuals with inadequate HL had a higher risk of having DR, and this association was still statistically significant after adjusting for HbA1c, low-density lipoprotein cholesterol, systolic blood pressure, and diastolic blood pressure. In conclusion, HL is related to DR without the mediation of classical clinical variables.

4.
Heliyon ; 9(9): e19672, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37809460

RESUMEN

Additive Manufacturing (AM) demonstrates significant potential with rapid growth and widespread industrial adoption. To support the integration and innovation of AM technologies, the development of guidance tools and support methods are crucial, and a technological roadmap can assist in this effort. Despite its widespread use in production processes, the need for further research on the potential impact of AM remains significant. The full impact of AM is still uncertain and lacks consensus, highlighting the need for increased knowledge and investment from the scientific community and organizations. While the benefits of AM are recognized, the challenges of its adoption are not entirely known. AM will bring changes in the way organizations create, distribute, and derive value. Thus, in this article, a roadmap for AM is proposed and presented as a tool to map technological knowledge on the implementation and evolution of AM and serve as a strategic guide for organizations. The methodology for its elaboration involves three phases: planning and preparation, roadmap development, and review and update. Through a literature review, database and project consultation, and questionnaires to Portuguese companies that use AM in their production process it was possible to characterize the AM technology and through the visual format, based on a time horizon, summarize in a common framework all the information about the current and future state of AM in Portugal. The results of this study show that research and development initiatives are essential to promote the evolution of knowledge of the AM technology. Throughout this study and with the development of the roadmap it is anticipated that in the near future the AM will be widely used for prototyping and manufacturing of components and may be used for direct production in the short to medium term. It was also found that the main obstacles to the implementation of AM are the economic/productivity factors and the shortage of professionals with knowledge and skills in the area.

5.
J Endocrinol Invest ; 45(10): 1865-1874, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-35635644

RESUMEN

PURPOSE: After a recommendation for iodine supplementation in pregnancy has been issued in 2013 in Portugal, there were no studies covering iodine status in pregnancy in the country. The aim of this study was to assess iodine status in pregnant women in Porto region and its association with iodine supplementation. METHODS: A cross-sectional study was conducted at Centro Hospitalar Universitário São João, Porto, from April 2018 to April 2019. Pregnant women attending the 1st trimester ultrasound scan were invited to participate. Exclusion criteria were levothyroxine use, gestational age < 10 and ≥ 14 weeks, non-evolutive pregnancy at recruitment and non-signing of informed consent. Urinary iodine concentration (UIC) was measured in random spot urine by inductively coupled plasma-mass spectrometry. RESULTS: Median UIC was 104 µg/L (IQR 62-189) in the overall population (n = 481) of which 19% had UIC < 50 µg/L. Forty three percent (n = 206) were not taking an iodine-containing supplement (ICS) and median UIC values were 146 µg/L (IQR 81-260) and 74 µg/L (IQR 42-113) in ICS users and non-users, respectively (p < 0.001). Not using an ICS was an independent risk factor for iodine insufficiency [adjusted OR (95% CI) = 6.00 (2.74, 13.16); p < 0.001]. Iodised salt use was associated with increased median iodine-to-creatinine ratio (p < 0.014). CONCLUSIONS: A low compliance to iodine supplementation recommendation in pregnancy accounted for a mild-to-moderately iodine deficiency. Our results evidence the need to support iodine supplementation among pregnant women in countries with low household coverage of iodised salt. Trial registration number NCT04010708, registered on the 8th July 2019.


Asunto(s)
Yodo , Mujeres Embarazadas , Estudios Transversales , Suplementos Dietéticos , Femenino , Humanos , Lactante , Estado Nutricional , Portugal/epidemiología , Embarazo , Factores de Riesgo , Cloruro de Sodio Dietético
6.
7.
FEMS Microbiol Ecol ; 96(8)2020 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-32589193

RESUMEN

Niche is a fundamental concept in ecology. It integrates the sum of biotic and abiotic environmental requirements that determines a taxon's distribution. Microbiologists currently lack quantitative approaches to address niche-related hypotheses. We tested four approaches for the quantification of niche breadth and overlap of taxa in amplicon sequencing datasets, with the goal of determining generalists, specialists and environmental-dependent distributions of community members. We applied these indices to in silico training datasets first, and then to real human gut and desert biological soil crust (biocrust) case studies, assessing the agreement of the indices with previous findings. Implementation of each approach successfully identified a priori conditions within in silico training data, and we found that by including a limit of quantification based on species rank, one could identify taxa falsely classified as specialists because of their low, sparse counts. Analysis of the human gut study offered quantitative support for Bacilli, Gammaproteobacteria and Fusobacteria specialists enriched after bariatric surgery. We could quantitatively characterise differential niche distributions of cyanobacterial taxa with respect to precipitation gradients in biocrusts. We conclude that these approaches, made publicly available as an R package (MicroNiche), represent useful tools to assess microbial environment-taxon and taxon-taxon relationships in a quantitative manner.


Asunto(s)
Cianobacterias , Ecosistema , Cianobacterias/genética , Ecología , Humanos
8.
Biomed Phys Eng Express ; 6(3): 035018, 2020 04 21.
Artículo en Inglés | MEDLINE | ID: mdl-33438663

RESUMEN

Numerical models are an alternative to measurements of x-ray energy spectra when validated by comparative methods that assess the similarity of experimental and calculated spectra. In this work, we compared x-ray energy spectra using several methodologies and determined the methodology with highest statistical power among them. Experiments and Monte Carlo (MC) simulations were used to generate a set of 65 experimental and simulated x-ray mammography spectra pairs typically used in mammography applications. They were generated using Tungsten and Molybdenum targets and Molybdenum and Rhodium filters. The x-ray beams were transmitted through breast tissue equivalent material (bTEM) plates with different glandularities and thicknesses, and the transmitted beam was detected using solid-state x-ray spectrometry with a Cadmium Telluride (CdTe) diode. The MC simulations used the PENELOPE code. Additional uncertainties, beyond that from counting, were propagated using the MC method. Quantitative comparative methods based on the [Formula: see text] statistics, the first and second half-value layers, the mean energy, the effective energy, and the non-parametric u-test were applied and their specificity (true negative rate) was assessed. The polyenergetic normalized glandular dose (DgNp) to a 6 cm breast of 50/50 glandularity was derived from the spectra. In this work, the [Formula: see text] statistics attained the highest score; therefore, it is the most indicated metric for the x-ray energy spectra comparative evaluations. The contribution of the additional uncertainties was important, being responsible for up to 98% of the spectra total uncertainty and shifting the mean of the evaluated [Formula: see text] to 1.2(1), compatible with its expected value. The use of non-parametric test is discouraged by our results, since it failed to distinguish spectra pairs that resulted in up to 72% discrepant DgNp.


Asunto(s)
Compuestos de Cadmio/química , Mamografía/instrumentación , Mamografía/métodos , Telurio/química , Algoritmos , Simulación por Computador , Reacciones Falso Positivas , Femenino , Humanos , Procesamiento de Imagen Asistido por Computador , Modelos Estadísticos , Modelos Teóricos , Molibdeno , Método de Montecarlo , Distribución Normal , Reproducibilidad de los Resultados , Rodio , Sensibilidad y Especificidad , Espectrofotometría , Tungsteno , Incertidumbre , Rayos X
11.
PLoS One ; 11(12): e0167531, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27907185

RESUMEN

Hancornia speciosa Gomes (Apocynaceae) is a fruit tree, popularly known as mangabeira, and it is widely distributed throughout Brazil. Several parts of the plant are used in folk medicine, and the leaf and bark extracts have anti-inflammatory, antihypertensive, antidiabetic, and antimicrobial properties. In this study, we investigated the chemical composition of the ethanolic extract of Hancornia speciosa leaves (EEHS) and its antioxidant, antimicrobial, and cytotoxic activities as well as the mechanisms involved in cell death. The chemical compounds were identified by liquid chromatography coupled to mass spectrometry (LC-MS/MS). The antioxidant activity of the EEHS was investigated using the method that involves the scavenging of 2,2-diphenyl-1-picrylhydrazyl free radicals as well as the inhibition of oxidative hemolysis and lipid peroxidation induced by 2,2'-azobis (2-amidinopropane) in human erythrocytes. The antimicrobial activity was determined by calculating the minimum inhibitory concentration, minimum bactericidal concentration, minimum fungicidal concentration, and zone of inhibition. Kasumi-1 leukemic cells were used to assess the cytotoxic activity and mechanisms involved in cell death promoted by the EEHS. The chemical compounds identified were quinic acid, chlorogenic acid, catechin, rutin, isoquercitrin, kaempferol-rutinoside, and catechin-pentoside. The EEHS demonstrated antioxidant activity via the sequestration of free radicals, inhibition of hemolysis, and inhibition of lipid peroxidation in human erythrocytes incubated with an oxidizing agent. The antimicrobial activity was observed against American Type Culture Collection (ATCC) and hospital strains of bacteria and fungi, filamentous fungi and dermatophytes. The cytotoxic activity of the EEHS was induced by apoptosis, reduction of the mitochondrial membrane potential, and activation of cathepsins. Together, these results indicate the presence of phenolic compounds and flavonoids in the EEHS and that their antioxidant, antimicrobial, and cytotoxic activities in acute myeloid leukemia cells are mediated by apoptosis.


Asunto(s)
Antiinfecciosos/farmacología , Antioxidantes/farmacología , Apocynaceae/química , Citotoxinas/farmacología , Fenoles/farmacología , Extractos Vegetales/farmacología , Antiinfecciosos/aislamiento & purificación , Antioxidantes/aislamiento & purificación , Compuestos de Bifenilo/antagonistas & inhibidores , Candida albicans/efectos de los fármacos , Candida albicans/crecimiento & desarrollo , Catequina/aislamiento & purificación , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Ácido Clorogénico/aislamiento & purificación , Citotoxinas/aislamiento & purificación , Eritrocitos/citología , Eritrocitos/efectos de los fármacos , Bacterias Gramnegativas/efectos de los fármacos , Bacterias Gramnegativas/crecimiento & desarrollo , Bacterias Grampositivas/efectos de los fármacos , Bacterias Grampositivas/crecimiento & desarrollo , Hemólisis/efectos de los fármacos , Humanos , Quempferoles/aislamiento & purificación , Pruebas de Sensibilidad Microbiana , Fenoles/aislamiento & purificación , Picratos/antagonistas & inhibidores , Extractos Vegetales/química , Hojas de la Planta/química , Quercetina/análogos & derivados , Quercetina/aislamiento & purificación , Ácido Quínico/aislamiento & purificación , Rutina/aislamiento & purificación
13.
Eur Psychiatry ; 30(6): 756-64, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-26163920

RESUMEN

BACKGROUND: Previous studies indicate a possible association between early emotional trauma (EET) and the development of anxiety disorders (ADs) in adult life. However, no previous studies have compiled the findings of such studies and analyzed their statistical significance. Therefore, the objective of this study was to conduct a systematic literature review and meta-analysis to determine possible associations between EET and three ADs (panic, generalized anxiety, and social anxiety disorders). METHODS: A systematic search was conducted in PubMed, PsycInfo, and Scielo with no publication date limitations. A total of 2127 studies were found, 32 studies of which were selected for the systematic review and 13 studies of which were selected for the meta-analysis. RESULTS: High prevalence rates of different EETs were observed among the individuals with ADs (median: 18%-45%). The results of the meta-analysis indicated that individuals with EETs were 1.9- to 3.6-fold more likely to develop ADs compared with a control group of healthy individuals. Emotional traumas were the main risk factor for social anxiety disorder. However, no specific associations were found for the other ADs. CONCLUSIONS: EET is a risk factor for ADs, underscoring the importance of preventive measures to combat the development of these disorders. Moreover, the identification of EETs among patients with ADs is essential for implementing remedial measures to minimize the impact and damage arising from this association by decreasing the risk and severity of symptoms and to improve the response rate to treatment of ADs.


Asunto(s)
Trastornos de Ansiedad , Trauma Psicológico , Adulto , Edad de Inicio , Trastornos de Ansiedad/epidemiología , Trastornos de Ansiedad/etiología , Trastornos de Ansiedad/psicología , Niño , Humanos , Prevalencia , Trauma Psicológico/complicaciones , Trauma Psicológico/epidemiología , Psicopatología , Factores de Riesgo , Estrés Psicológico/psicología
14.
J Phys Condens Matter ; 26(5): 055003, 2014 Feb 05.
Artículo en Inglés | MEDLINE | ID: mdl-24334623

RESUMEN

We have studied the oxidation of CO over Rh(100) using high pressure x-ray photoelectron spectroscopy under CO and O2 pressures ranging from 0.01 to 1 mbar. The results show a very low or no conversion for the CO covered surface found at low temperatures, while the activity rises slightly when the temperature is high enough for some CO to desorb, exposing surface sites for dissociative O2 adsorption. As the temperature is increased further, more CO desorbs and oxygen replaces CO as the dominating species at the surface. At the same time we find a sudden increase in the reactivity, such that all CO that reaches the surface is instantly transformed into CO2. We find that the O coverage in the active state is highly dependent on the total pressure and, although we do not detect any presence of a surface oxide as in previous surface x-ray diffraction studies, the highest O coverage indicates that the surface is close to being oxidized.

15.
Arq. bras. med. vet. zootec ; 65(3): 927-933, June 2013. graf, tab
Artículo en Portugués | LILACS | ID: lil-679131

RESUMEN

Avaliaram-se hambúrgueres de aparas de jacaré-do-pantanal (Caiman yacare) quanto à composição centesimal, cor e análise sensorial. O delineamento foi inteiramente ao acaso, em três tratamentos: T1= sem defumação; T2= defumação a quente e T3= defumação líquida, e nove repetições. As aparas foram moídas e condimentadas para o hambúrguer. Os hambúrgueres para defumação a quente foram colocados no defumador 60 min a 60ºC com gerador de fumaça por fricção. Foi pulverizada fumaça líquida, sobre os produtos (T3), e estes foram colocados em desidratador por 60 min a 60ºC. Houve diferença significativa quanto à composição centesimal entre os hambúrgueres defumados, T2 = 43,1% e T3 = 60,9%, e verificou-se menor teor de umidade em relação aos sem defumação, 73,3%. A proteína, 39,9%, e as cinzas, 6,1%, foram mais altas nos defumados a quente. Os hambúrgueres defumados a quente apresentaram menor luminosidade, 42,05, e maiores valores do croma a*, 14,65, e b*, 28,57, em relação aos demais tratamentos. As variáveis sensoriais foram significativas para sabor, textura e aceitação geral. Os produtos defumados a quente apresentaram a pior aceitação. Concluiu-se que a defumação a quente proporciona produtos com menor teor de umidade, com pigmentação mais intensa, porém menos aceitos pelos provadores.


Hamburgers made from minced meat of Pantanal caiman (Caiman yacare) were evaluated for their centesimal composition, color and sensory perception. The experiment was structured in a completely randomized design with three treatments (T1 = no smoke; T2 = smoked with hot smoke and T3 = smoked with liquid smoke), with nine repetitions each. The meat was minced and seasoned for the hamburgers. The hamburgers destined to hot smoking were placed in the smoker (60 min at 60ºC) with smoke generated through friction. The liquid smoke was sprayed in the samples (T3), next they were placed in dehydrators (60 min at 60ºC). There was a significant difference in centesimal composition, the smoked hamburgers (T2 = 43.1% and T3 = 60.9%) presenting significantly less moisture than non-smoked products (73.3%). Protein (39.9%) and ash (6.1%) were higher for the hot-smoked samples. The hot-smoked hamburgers had less luminosity (42.05) and higher values of chroma a* (14.65) and b* (28.57) than the other treatments. The sensorial parameters evaluated were significant for flavor, texture and general acceptance. The hot-smoked products had the worst acceptance. It was concluded that the hot smoke provided products with less moisture and higher pigmentation, but with less acceptance from the judges.


Asunto(s)
Animales , Carne/análisis , Alimentos , Caimanes y Cocodrilos
16.
Genet Mol Res ; 12(2): 1005-11, 2013 Apr 02.
Artículo en Inglés | MEDLINE | ID: mdl-23613246

RESUMEN

Cancer has become the leading cause of death in developing countries due to increased life expectancy of the population and changes in lifestyle. Studies on active principles of plant have motivated researchers to develop new antitumor agents that are specific and effective for treatment of neoplasms. Kaurane diterpenes are considered important compounds in the development of new and highly effective anticancer chemotherapeutic agents due to their cytotoxic properties in the induction of apoptosis. We evaluated the cytotoxic and apoptotic activity of the epimer of kaurenoic acid (EKA) isolated from the medicinal plant Croton antisyphiliticus (Euphorbiaceae) toward tumor cell lines HeLa and B-16 and normal fibroblasts 3T3. Based on analyses with the MTT test, EKA showed cytotoxic activity, with half maximal inhibitory concentration values of 59.41, 68.18 and 60.30 µg/mL for the B-16, HeLa and 3T3 cell lines, respectively. The assay for necrotic or apoptotic cells by differential staining showed induction of apoptosis in all three cell lines. We conclude that EKA is not selective between tumor and normal cell lines; the mechanism of action of EKA is induction of apoptosis, which is part of the innate mechanism of cell defense against neoplasia.


Asunto(s)
Antineoplásicos/toxicidad , Apoptosis/efectos de los fármacos , Croton/química , Diterpenos/toxicidad , Extractos Vegetales/toxicidad , Animales , Antineoplásicos/química , Línea Celular Tumoral , Diterpenos/química , Células HeLa , Humanos , Concentración 50 Inhibidora , Melanoma Experimental , Ratones , Células 3T3 NIH , Extractos Vegetales/química
17.
Braz J Med Biol Res ; 46(3): 293-8, 2013 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-23532267

RESUMEN

The objective of this study was to evaluate gastric emptying (GE) in pediatric patients with functional constipation. GE delay has been reported in adults with functional constipation. Gastric emptying studies were performed in 22 children with chronic constipation, fecal retention and fecal incontinence, while presenting fecal retention and after resuming regular bowel movements. Patients (18 boys, median age: 10 years; range: 7.2 to 12.7 years) were evaluated in a tertiary pediatric gastroenterology clinic. Gastric half-emptying time of water (reference range: 12 ± 3 min) was measured using a radionuclide technique immediately after first patient evaluation, when they presented fecal impaction (GE1), and when they achieved regular bowel movements (GE2), 12 ± 5 weeks after GE1. At study admission, 21 patients had reported dyspeptic symptoms, which were completely relieved after resuming regular bowel movements. Medians (and interquartile ranges) for GE1 and GE2 were not significantly different [27.0 (16) and 27.5 (21) min, respectively (P = 0.10)]. Delayed GE seems to be a common feature among children with chronic constipation and fecal retention. Resuming satisfactory bowel function and improvement in dyspeptic symptoms did not result in normalization of GE data.


Asunto(s)
Estreñimiento/fisiopatología , Vaciamiento Gástrico/fisiología , Tránsito Gastrointestinal/fisiología , Agua , Niño , Enfermedad Crónica , Estreñimiento/diagnóstico por imagen , Incontinencia Fecal/fisiopatología , Femenino , Humanos , Masculino , Cintigrafía , Índice de Severidad de la Enfermedad
19.
Braz. j. med. biol. res ; 46(3): 293-298, 15/mar. 2013. tab, graf
Artículo en Inglés | LILACS | ID: lil-670898

RESUMEN

The objective of this study was to evaluate gastric emptying (GE) in pediatric patients with functional constipation. GE delay has been reported in adults with functional constipation. Gastric emptying studies were performed in 22 children with chronic constipation, fecal retention and fecal incontinence, while presenting fecal retention and after resuming regular bowel movements. Patients (18 boys, median age: 10 years; range: 7.2 to 12.7 years) were evaluated in a tertiary pediatric gastroenterology clinic. Gastric half-emptying time of water (reference range: 12 ± 3 min) was measured using a radionuclide technique immediately after first patient evaluation, when they presented fecal impaction (GE1), and when they achieved regular bowel movements (GE2), 12 ± 5 weeks after GE1. At study admission, 21 patients had reported dyspeptic symptoms, which were completely relieved after resuming regular bowel movements. Medians (and interquartile ranges) for GE1 and GE2 were not significantly different [27.0 (16) and 27.5 (21) min, respectively (P = 0.10)]. Delayed GE seems to be a common feature among children with chronic constipation and fecal retention. Resuming satisfactory bowel function and improvement in dyspeptic symptoms did not result in normalization of GE data.


Asunto(s)
Niño , Femenino , Humanos , Masculino , Estreñimiento/fisiopatología , Vaciamiento Gástrico/fisiología , Tránsito Gastrointestinal/fisiología , Agua , Enfermedad Crónica , Estreñimiento , Incontinencia Fecal/fisiopatología , Índice de Severidad de la Enfermedad
20.
Phys Rev Lett ; 110(11): 117601, 2013 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-25166577

RESUMEN

We present high-pressure x-ray photoelectron spectroscopy (HP-XPS) and first-principles kinetic Monte Carlo study addressing the nature of the active surface in CO oxidation over Pd(100). Simultaneously measuring the chemical composition at the surface and in the near-surface gas phase, we reveal both O-covered pristine Pd(100) and a surface oxide as stable, highly active phases in the near-ambient regime accessible to HP-XPS. Surprisingly, no adsorbed CO can be detected during high CO(2) production rates, which can be explained by a combination of a remarkably short residence time of the CO molecule on the surface and mass-transfer limitations in the present setup.

SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA
...