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1.
BMC Plant Biol ; 24(1): 638, 2024 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-38971728

RESUMO

BACKGROUND: Drought periods are major evolutionary triggers of wood anatomical adaptive variation in Lower Tropical Montane Cloud Forests tree species. We tested the influence of historical drought events on the effects of ecological stress memory on latewood width and xylem vessel traits in two relict hickory species (Carya palmeri and Carya myristiciformis) from central-eastern Mexico. We hypothesized that latewood width would decrease during historical drought years, establishing correlations between growth and water stress conditions, and that moisture deficit during past tree growth between successive drought events, would impact on wood anatomical features. We analyzed latewood anatomical traits that developed during historical drought and pre- and post-drought years in both species. RESULTS: We found that repeated periods of hydric stress left climatic signatures for annual latewood growth and xylem vessel traits that are essential for hydric adaptation in tropical montane hickory species. CONCLUSIONS: Our results demonstrate the existence of cause‒effect relationships in wood anatomical architecture and highlight the ecological stress memory linked with historical drought events. Thus, combined time-series analysis of latewood width and xylem vessel traits is a powerful tool for understanding the ecological behavior of hickory species.


Assuntos
Secas , Madeira , México , Madeira/anatomia & histologia , Madeira/fisiologia , Madeira/crescimento & desenvolvimento , Estresse Fisiológico , Xilema/fisiologia , Xilema/anatomia & histologia , Clima Tropical , Árvores/fisiologia , Árvores/anatomia & histologia , Árvores/crescimento & desenvolvimento , Fagales/anatomia & histologia , Fagales/fisiologia , Adaptação Fisiológica
2.
ACS Omega ; 8(19): 17234-17244, 2023 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-37214712

RESUMO

In this study, CuO-TiO2 nanofiber catalysts were fabricated by an electrospinning process, followed by thermal annealing at various temperatures ranging from 300 to 700 °C. The phase transformation from CuO to metallic Cu was carried out through immersion treatment in NaBH4 solution. The resulting CuO-TiO2 and Cu-CuO-TiO2 nanofibrous mats were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), and Brunauer-Emmett-Teller (BET) analysis. The results revealed that the crystalline phase composition of the nanofibrous mats considerably affected the efficiency of photocatalytic reduction, where the CuO-TiO2 catalysts with a predominant anatase content was found to be more photoactive than the rutile phase. Similarly, the presence of both Cu and CuO species was more beneficial for promoting the activity of fibers by acting as an interim location for facilitating the electron transfer. The fabricated Cu-CuO-TiO2 nanofibrous mat with a ratio presented high conversion (∼99%) within several minutes with the apparent pseudo-first-order rate constant of 0.42 and 0.50 min-1 in the absence and presence of UV light irradiation as well as excellent stability in recycling runs with a stable conversion efficiency of 97% or higher over five successive catalytic cycles.

3.
Pediatr Transplant ; 25(8): e14105, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34328249

RESUMO

BACKGROUND: Enterocutaneous fistula (ECF) is a serious and complex problem when affecting children, being responsible for a high morbidity burden, with an estimated mortality rate of 10 to 20%. There are many therapeutic options, including surgery and a wide variety of nonoperative strategies. Prognosis of ECF closure depends on the output and also on the patency of distal bowel. Spontaneous closure without operative intervention occurs in approximately 50% of patients with lateral ECF and distal bowel transit, but this drastically decreases in high output fistulas. High-volume fistula output and consequent skin damage are a great challenge for the health-care team. METHODS: We describe a postoperative complication that required a new nonoperative technique for the transient management of a lateral high-output ECF, involving the insertion of an occlusive device in order to redirect intestinal content to the distal bowel, reducing the fistula output. RESULTS AND CONCLUSIONS: The main benefit of this nonoperative technique is the ability to occlude a high-output fistula, allowing the distal flow to be restored and reducing abdominal wall damage, as a bridge to definitive surgical closure.


Assuntos
Fístula Intestinal/cirurgia , Intestino Delgado/transplante , Complicações Pós-Operatórias/cirurgia , Síndrome do Intestino Curto/cirurgia , Criança , Drenagem/instrumentação , Desenho de Equipamento , Humanos , Fístula Intestinal/etiologia , Masculino , Complicações Pós-Operatórias/etiologia
4.
Benef Microbes ; 10(8): 873-882, 2019 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-31965841

RESUMO

Available reviews have shown potential effects of probiotics on neurobehavioral outcomes through 'gut-brain axis' mechanism in adults. However, reviews on cognitive function in children and adolescents are lacking. Therefore, we conducted a systematic review of randomised controlled trials (RCTs) of the effect of probiotic supplementation on cognitive function in children and adolescents. A search of four databases (Cochrane Central Register of Controlled Trials, PsycARTICLES, Scopus, PubMed) was conducted to identify RCTs published from January 1990 to December 2018. Seven studies met the inclusion criteria and their cognitive outcomes were analysed. Only one study found a positive result with Lactobacillus rhamnosus GG (LGG) 1×1010 cfu supplementation with outcomes on attention deficit hyperactivity disorder (ADHD) or Asperger syndrome (AS) manifestations as diagnosed using the International Classification of Diseases-10 criteria. The supplementations were administered to Finnish mothers for 4 weeks before delivery and continuously given for 6 months after delivery if they breastfed, or to the children. ADHD or AS was diagnosed at the age of 13 years in 17.1% children in the placebo and none in the probiotic group (P=0.008). This study found significant differences in species composition and number of cells belonging to the genus Bifidobacterium between healthy children and children who later developed ADHD or AS at different time points. Six remaining studies with varying strains, durations of intervention, start-time of administration, and outcomes demonstrated no difference in cognition after probiotic supplementation. Metagenomic analyses on gut microbiota composition were not performed in any of these studies. In conclusion, the favourable effect of probiotic supplementation on cognitive function in children and adolescents was observed in one study with LGG supplementation by a risk reduction of developing ADHD or AS (i.e. autism). More long-term and follow-up trials using probiotics identifying the effect on cognition are warranted before routine use.


Assuntos
Cognição/efeitos dos fármacos , Probióticos/farmacologia , Adolescente , Síndrome de Asperger/prevenção & controle , Síndrome de Asperger/psicologia , Transtorno do Deficit de Atenção com Hiperatividade/prevenção & controle , Transtorno do Deficit de Atenção com Hiperatividade/psicologia , Criança , Humanos , Probióticos/administração & dosagem , Ensaios Clínicos Controlados Aleatórios como Assunto , Resultado do Tratamento
5.
Curr Clin Pharmacol ; 14(2): 91-100, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30501602

RESUMO

BACKGROUND: muscarinic acetylcholine receptors (mAChRs) have attracted interest as targets for therapeutic interventions in different illnesses like Alzheimer´s disease, viral infections and different tumors. Regarding the latter, many authors have studied each subtype of mAChRs, which seem to be involved in the progression of distinct types of malignancies. METHODS: We carefully revised research literature focused on mAChRs expression and signaling as well as in their involvement in cancer progression and treatment. The characteristics of screened papers were described using the mentioned conceptual framework. RESULTS: Muscarinic antagonists and agonists have been assayed for the treatment of tumors established in lung, brain and breast with beneficial effects. We described an up-regulation of mAChRs in mammary tumors and the lack of expression in non-tumorigenic breast cells and normal mammary tissues. We and others demonstrated that muscarinic agonists can trigger anti-tumor actions in a dose-dependent manner on tumors originated in different organs like brain or breast. At pharmacological concentrations, they exert similar effects to traditional chemotherapeutic agents. Metronomic chemotherapy refers to the administration of anti-cancer drugs at low doses with short intervals among them, and it is a different regimen applied in cancer treatment reducing malignant growth and angiogenesis, and very low incidence of adverse effects. CONCLUSION: The usage of subthreshold concentrations of muscarinic agonists combined with conventional chemotherapeutic agents could be a promising tool for breast cancer therapy.


Assuntos
Antineoplásicos/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Agonistas Muscarínicos/uso terapêutico , Receptores Muscarínicos/metabolismo , Receptores Muscarínicos/uso terapêutico , Antineoplásicos/farmacologia , Quimioterapia Combinada , Feminino , Humanos , Masculino
6.
Actual. nutr ; 18(4): [108]-[114], Diciembre 2017.
Artigo em Espanhol | LILACS | ID: biblio-969970

RESUMO

Introducción: la enfermedad celíaca (EC) es un trastorno sistémico, mediado inmunológicamente y desencadenado por la ingestión de gluten en individuos genéticamente susceptibles. El único tratamiento es una dieta libre de gluten estricta y de por vida, que requiere cambiar un hábito tan cotidiano y consolidado como la alimentación. Objetivos: conocer los servicios gastronómicos comerciales del distrito centro de la ciudad de Santa Fe que brindan alimentos libres de gluten, la variedad de preparaciones aptas y el conocimiento de los manipuladores sobre la enfermedad y la manipulación segura de estos alimentos. Materiales y métodos: estudio descriptivo, observacional y transversal, aplicado a una muestra de 80 servicios gastronómicos. Se realizaron dos encuestas (una al manipulador de alimentos y otra al encargado del establecimiento) y una observación directa de la lista de menús. Resultados: el 90% de los manipuladores informó conocer qué es la EC. El 10% (n=8) de los establecimientos contaba con al menos un menú libre de gluten, y de éstos, sólo el 12,5% (1) cumplía con todas las pautas para la elaboración de alimentos libres de gluten. El 50% (4) contaba con cinco o más platos sin gluten, limitándose la variedad a farináceos, carnes con guarnición y ensaladas. Conclusiones: los manipuladores de alimentos conocen algunos aspectos de la EC, sin embargo, son escasos los establecimientos que brindan preparaciones seguras libres de gluten. Es necesario dar mayores oportunidades sociales a las personas con EC a fin de reducir el riesgo de transgresiones alimentarias.


Introduction: celiac disease (CD) is a systemic disorder, mediated immunologically and triggered by the ingestion of gluten in genetically susceptible individuals. The only treatment is a strict gluten-free diet for life, which requires changed a habit as daily and consolidated as food. Objectives: to know the commercial gastronomic services of the downtown district of the city of Santa Fe that offer gluten-free foods, the variety of suitable preparations and the knowledge of the manipulators about the disease and the safe handling of these foods. Materials and methods: descriptive, observational and transversal study, applied to a sample of 80 gastronomic services. Two surveys were carried out (one to the food handler and another to the establishment manager) and a direct observation of the menu list. Results: the 90% of the food handlers were informed about the disease. 10% of the facilities (n=8) had at least one glutenfree menu, of which just only a 12.5% (1) fulfilled all the requirements for the processing of gluten-free foodstuffs. Only a 50% (4) had five or more gluten-free dishes which were mainly prepared with starchy products, garnished meat and vegetables. Conclusions: while many food handlers know certain aspects of CD, only a few food facilities provide safe glutenfree preparations. It is necessary to promote greater social opportunities to those suffering from CD in order to reduce the risk of dietary infringements.


Assuntos
Humanos , Argentina , Doença Celíaca , Alimentos
7.
Eur J Clin Nutr ; 62(3): 373-8, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17342165

RESUMO

OBJECTIVE: To describe the vitamin D status of women living in two Asian cities,--Jakarta (6 degrees S) and Kuala-Lumpur (2 degrees N), to examine the association between plasma 25-hydroxyvitamin D and parathyroid hormone (PTH) concentrations, and to determine a threshold for plasma 25-hydroxyvitamin D above which there is no further suppression of PTH. Also, to determine whether dietary calcium intake influences the relationship between PTH and 25-hydroxyvitamin D. DESIGN: Cross-sectional. SETTING: Jakarta, Indonesia and Kuala Lumpur, Malaysia. PARTICIPANTS: A convenience sample of 504 non-pregnant women 18-40 years. MAIN MEASURES: Plasma 25-hydroxyvitamin D and PTH. RESULTS: The mean 25-hydroxyvitamin D concentration was 48 nmol/l. Less than 1% of women had a 25-hydroxyvitamin D concentration indicative of vitamin D deficiency (<17.5 nmol/l); whereas, over 60% of women had a 25-hydroxyvitamin D concentration indicative of insufficiency (<50 nmol/l). We estimate that 52 nmol/l was the threshold concentration for plasma 25-hydroxyvitamin D above which no further suppression of PTH occurred. Below and above this concentration the slopes of the regression lines were -0.18 (different from 0; P=0.003) and -0.01 (P=0.775), respectively. The relation between vitamin D status and parathyroid hormone concentration did not differ between women with low, medium or high calcium intakes (P=0.611); however, even in the highest tertile of calcium intake, mean calcium intake was only 657 mg/d. CONCLUSION: On the basis of maximal suppression of PTH we estimate an optimal 25-hydroxyvitamin D concentration of approximately 50 nmol/l. Many women had a 25-hydroxyvitamin D below this concentration and may benefit from improved vitamin D status.


Assuntos
Estado Nutricional , Hormônio Paratireóideo/sangue , Deficiência de Vitamina D/sangue , Deficiência de Vitamina D/fisiopatologia , Vitamina D/sangue , Adolescente , Adulto , Estudos Transversais , Feminino , Humanos , Indonésia , Malásia , Vitamina D/análogos & derivados , Saúde da Mulher
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