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1.
Neurología (Barc., Ed. impr.) ; 39(3): 244-253, Abr. 2024. ilus, tab, graf
Artigo em Espanhol | IBECS | ID: ibc-231690

RESUMO

Introducción: La relación entre la corteza entorrinal y el hipocampo ha sido estudiada por diferentes autores, que han destacado la importancia de las células de cuadrícula, las células de posicionamiento y la conexión trisináptica en los procesos que regulan: la persistencia de la memoria espacial, explícita y reciente, y su posible afección con el envejecimiento. Objetivo: Observar si existen diferencias en el tamaño y número de células de cuadrícula contenidas en la lámina iii de la corteza entorrinal y en la capa granular del giro dentado del hipocampo de pacientes mayores. Métodos: Realizamos estudios posmortem del cerebro de 6 sujetos de edades comprendidas entre los 56 y 87 años. Los cortes de cerebros que contenían el giro dentado del hipocampo y la corteza entorrinal adyacente se tiñeron con el método de Klüver-Barrera, después se midió, mediante el programa Image J, el área neuronal individual, el área neuronal total, así como el número de neuronas, contenidas en cuadrículas rectangulares a nivel de la lámina iii de la corteza entorrinal y la lámina ii del giro dentado y se llevó a cabo un análisis estadístico. Resultados: Se ha observado una reducción de la población celular de la capa piramidal externa de la corteza entorrinal, así como de las neuronas de la capa granular del giro dentado relacionada con el envejecimiento. Conclusión: Nuestros resultados indican que el envejecimiento produce una disminución en el tamaño y la densidad neuronal en las células de cuadrícula de la corteza entorrinal y de posicionamiento del giro dentado.(AU)


Introduction: The relationship between the entorhinal cortex and the hippocampus has been studied by different authors, who have highlighted the importance of grid cells, place cells, and the trisynaptic circuit in the processes that they regulate: the persistence of spatial, explicit, and recent memory and their possible impairment with ageing. Objective: We aimed to determine whether older age causes changes in the size and number of grid cells contained in layer III of the entorhinal cortex and in the granular layer of the dentate gyrus of the hippocampus. Methods: We conducted post-mortem studies of the brains of 6 individuals aged 56-87 years. The brain sections containing the dentate gyrus and the adjacent entorhinal cortex were stained according to the Klüver-Barrera method, then the Image J software was used to measure the individual neuronal area, the total neuronal area, and the number of neurons contained in rectangular areas in layer III of the entorhinal cortex and layer II of the dentate gyrus. Statistical analysis was subsequently performed. Results: We observed an age-related reduction in the cell population of the external pyramidal layer of the entorhinal cortex, and in the number of neurons in the granular layer of the dentate gyrus. Conclusion: Our results indicate that ageing causes a decrease in the size and density of grid cells of the entorhinal cortex and place cells of the dentate gyrus.(AU)


Assuntos
Humanos , Masculino , Feminino , Pessoa de Meia-Idade , Idoso , Idoso de 80 Anos ou mais , Córtex Entorrinal , Hipocampo , Memória Espacial , Neurologia , Doenças do Sistema Nervoso
2.
Rev Neurosci ; 34(8): 915-932, 2023 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-37409540

RESUMO

The transsulfuration pathway (TSP) is a metabolic pathway involving sulfur transfer from homocysteine to cysteine. Transsulfuration pathway leads to many sulfur metabolites, principally glutathione, H2S, taurine, and cysteine. Key enzymes of the TSP, such as cystathionine ß-synthase and cystathionine γ-lyase, are essential regulators at multiple levels in this pathway. TSP metabolites are implicated in many physiological processes in the central nervous system and other tissues. TSP is important in controlling sulfur balance and optimal cellular functions such as glutathione synthesis. Alterations in the TSP and related pathways (transmethylation and remethylation) are altered in several neurodegenerative diseases, including Parkinson's disease, suggesting their participation in the pathophysiology and progression of these diseases. In Parkinson's disease many cellular processes are comprised mainly those that regulate redox homeostasis, inflammation, reticulum endoplasmic stress, mitochondrial function, oxidative stress, and sulfur content metabolites of TSP are involved in these damage processes. Current research on the transsulfuration pathway in Parkinson's disease has primarily focused on the synthesis and function of certain metabolites, particularly glutathione. However, our understanding of the regulation of other metabolites of the transsulfuration pathway, as well as their relationships with other metabolites, and their synthesis regulation in Parkinson´s disease remain limited. Thus, this paper highlights the importance of studying the molecular dynamics in different metabolites and enzymes that affect the transsulfuration in Parkinson's disease.


Assuntos
Cisteína , Doença de Parkinson , Humanos , Cisteína/metabolismo , Enxofre/metabolismo , Cistationina beta-Sintase/metabolismo , Glutationa/metabolismo
3.
Molecules ; 28(7)2023 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-37049769

RESUMO

Cheese is a product of animal origin with a high nutritional value, and it is one of the most consumed dairy foods in Mexico. In addition, Chihuahua cheese is the most consumed matured cheese in Mexico. In the production process of Chihuahua cheese, maturation is carried out by adding acid lactic microorganisms, mainly of the Lactococcus genus and, in some cases, also the Streptococcus and Lactobacillus genus. As part of the metabolism of fermenting microorganisms, biogenic amines can develop in matured foods, which result from the activity of amino decarboxylase enzymes. In cheeses, histamine and tyramine are the main amines that are formed, and the consumption of these represents a great risk to the health of consumers. In this work, the presence of biogenic amines (histamine and tyramine) was determined by HPLC at different times of the shelf life of Chihuahua cheeses. In addition, the presence of genes hdc and tdc that code for the enzymes responsible for the synthesis of these compounds (histidine and tyrosine decarboxylase, or HDC and TDC) was determined by molecular techniques. A significant correlation was observed between the presence of both histamine and tyramine at the end of shelf life with the presence of genes that code for the enzymes responsible for their synthesis.


Assuntos
Queijo , Histamina , Animais , Histamina/metabolismo , Tiramina , Aminas Biogênicas/análise , Lactobacillus/metabolismo
4.
J Clin Med ; 11(23)2022 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-36498796

RESUMO

OBJECTIVE: The aim of the present study was to compare the fascicle length, pennation angle, muscle thickness and stiffness of the biceps femoris long head, and eccentric hamstring strength between injured dominant limbs, injured non-dominant limbs, uninjured dominant limbs and uninjured non-dominant legs in previously injured players, and between dominant and non-dominant legs in uninjured elite soccer players. MATERIALS AND METHODS: Twenty elite soccer players participated in this study. Ultrasound imaging and MyotonPRO were used to determine the morphological and mechanical properties of the biceps femoris long head. Isokinetic and Nordic hamstring exercises were used to assess eccentric hamstring strength. RESULTS: Previously injured players showed substantially lower fascicle length and muscle thickness, and significantly higher biceps femoris long head stiffness than uninjured players, without differences between limbs. CONCLUSION: The morphological and mechanical properties of elite soccer players with hamstring injury history were different from those in uninjured players. The lack of differences between limbs showed that these values are characteristics of individual players that must be considered in the design of programs to prevent BFlh injury.

5.
Children (Basel) ; 9(12)2022 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-36553409

RESUMO

Hydrocephalus is a central nervous system condition characterized by CSF buildup and ventricular hypertrophy. It is divided into two types: communicative and non-communicating hydrocephalus. Congenital hydrocephalus has been linked to several changes in the subcommissural organ (SCO). However, it is unclear whether these changes occur before or as a result of the hydrocephalic illness. This report presents three cases of human fetuses with hydrocephalus: one non-communicating case, two communicating cases, and two controls. Hematoxylin-Eosin (H&E) or cresyl violet and immunohistochemistry with anti-transthyretin were used to analyze SCO morphological and secretory changes. We conclude that in the cases presented here, there could be an early regression in the SCO of the communicating cases that is not present in the non-communicating case.

6.
E-Cienc. inf ; 12(2)dic. 2022.
Artigo em Espanhol | LILACS-Express | LILACS | ID: biblio-1448122

RESUMO

Se estudia el comportamiento informativo de alumnos y docentes de la Facultad de Estudios Superiores Zaragoza (FESZ), de la Universidad Nacional Autónoma de México (UNAM), durante la pandemia ocasionada por el SARS-CoV-2, en la Biblioteca Digital UNAM ante el cierre total de las bibliotecas, lo que limitó la consulta presencial de libros y revistas impresas. Se llevó a cabo una investigación cuantitativa con la técnica de análisis de datos estadísticos a partir de las bitácoras de acceso a la Biblioteca Digital (BIDI UNAM) que en suma contempló 15,597 accesos, en comparación a dos periodos, antes y durante la pandemia, obteniendo como resultado un incremento en los accesos, sumado al impulso de estrategias de alfabetización informacional para el uso y aprovechamiento de los recursos de información, mismos que pueden ser integrados en los procesos de enseñanza y aprendizaje, fortaleciendo el modelo educativo de la FESZ.


The informational behavior of students and professors of the Facultad de Estudios Superiores Zaragoza (FESZ) of the Universidad Nacional Autónoma de México (UNAM) during the pandemic caused by SARS-CoV-2, is studied in the Biblioteca Digital UNAM (BIDI UNAM) before the total closure of libraries, which limited the consultation of printed books and journals. A quantitative research was carried out with the statistical data analysis technique from the access logs to the BIDI UNAM, wich in total included 15,597 accesses, compared to two periods, before and during the pandemic, obtaining as a result an increase in accesses, in addition to the promotion of information literacy strategies for the use and exploitation of information resources, which can be integrated into the teaching and learning processes, strengthening the educational model of the FESZ.

7.
Int J Mol Sci ; 23(20)2022 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-36293145

RESUMO

Hypertension is the leading cause of cardiovascular affection and premature death worldwide. The spontaneously hypertensive rat (SHR) is the most common animal model of hypertension, which is characterized by secondary ventricular dilation and hydrocephalus. Aquaporin (AQP) 1 and 4 are the main water channels responsible for the brain's water balance. The present study focuses on defining the expression of AQPs through the time course of the development of spontaneous chronic hypertension. We performed immunofluorescence and ELISA to examine brain AQPs from 10 SHR, and 10 Wistar−Kyoto (WKY) rats studied at 6 and 12 months old. There was a significant decrease in AQP1 in the choroid plexus of the SHR-12-months group compared with the age-matched control (p < 0.05). In the ependyma, AQP4 was significantly decreased only in the SHR-12-months group compared with the control or SHR-6-months groups (p < 0.05). Per contra, AQP4 increased in astrocytes end-feet of 6 months and 12 months SHR rats (p < 0.05). CSF AQP detection was higher in the SHR-12-months group than in the age-matched control group. CSF findings were confirmed by Western blot. In SHR, ependymal and choroidal AQPs decreased over time, while CSF AQPs levels increased. In turn, astrocytes AQP4 increased in SHR rats. These AQP alterations may underlie hypertensive-dependent ventriculomegaly.


Assuntos
Aquaporinas , Hidrocefalia , Hipertensão , Animais , Ratos , Ratos Endogâmicos SHR , Ratos Endogâmicos WKY , Aquaporina 1/metabolismo , Encéfalo/metabolismo , Hidrocefalia/metabolismo , Hipertensão/metabolismo , Água/metabolismo , Aquaporina 4/metabolismo , Aquaporinas/metabolismo
8.
Int J Mol Sci ; 23(18)2022 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-36142348

RESUMO

Aquaporin 4 (AQP4) is a cerebral glial marker that labels ependymal cells and astrocytes' endfeet and is the main water channel responsible for the parenchymal fluid balance. However, in brain development, AQP4 is a marker of glial stem cells and plays a crucial role in the pathophysiology of pediatric hydrocephalus. Gliogenesis characterization has been hampered by a lack of biomarkers for precursor and intermediate stages and a deeper understanding of hydrocephalus etiology is needed. This manuscript is a focused review of the current research landscape on AQP4 as a possible biomarker for gliogenesis and its influence in pediatric hydrocephalus, emphasizing reactive astrogliosis. The goal is to understand brain development under hydrocephalic and normal physiologic conditions.


Assuntos
Aquaporina 4 , Hidrocefalia , Astrócitos/metabolismo , Criança , Gliose , Humanos , Neuroglia/metabolismo , Água/metabolismo
9.
Neurologia (Engl Ed) ; 37(5): 371-382, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35672124

RESUMO

INTRODUCTION: The choroid plexuses, blood vessels, and brain barriers are closely related both in terms of morphology and function. Hypertension causes changes in cerebral blood flow and in small vessels and capillaries of the brain. This review studies the effects of high blood pressure (HBP) on the choroid plexuses and brain barriers. DEVELOPMENT: The choroid plexuses (ChP) are structures located in the cerebral ventricles, and are highly conserved both phylogenetically and ontogenetically. The ChPs develop during embryogenesis, forming a functional barrier during the first weeks of gestation. They are composed of highly vascularised epithelial tissue covered by microvilli, and their main function is cerebrospinal fluid (CSF) production. The central nervous system (CNS) is protected by the blood-brain barrier (BBB) and the blood-CSF barrier (BCSFB). While the BBB is formed by endothelial cells of the microvasculature of the CNS, the BCSFB is formed by epithelial cells of the choroid plexuses. Chronic hypertension induces vascular remodelling. This prevents hyperperfusion at HBPs, but increases the risk of ischaemia at low blood pressures. In normotensive individuals, in contrast, cerebral circulation is self-regulated, blood flow remains constant, and the integrity of the BBB is preserved. CONCLUSIONS: HBP induces changes in the choroid plexuses that affect the stroma, blood vessels, and CSF production. HBP also exacerbates age-related ChP dysfunction and causes alterations in the brain barriers, which are more marked in the BCSFB than in the BBB. Brain barrier damage may be determined by quantifying blood S-100ß and TTRm levels.


Assuntos
Células Endoteliais , Hipertensão , Envelhecimento , Encéfalo , Corioide , Humanos
10.
Neurología (Barc., Ed. impr.) ; 37(5): 371-382, Jun. 2022. ilus, tab, graf
Artigo em Inglês, Espanhol | IBECS | ID: ibc-205987

RESUMO

Introducción: Los plexos coroideos, los vasos sanguíneos y las barreras cerebrales están íntimamente relacionados tanto morfológica como funcionalmente. Por otro lado, la hipertensión produce cambios en el flujo sanguíneo y en los pequeños vasos y capilares cerebrales. El propósito de la presente revisión es estudiar los efectos de la hipertensión arterial sobre los plexos coroideos y las barreras cerebrales. Desarrollo: Los plexos coroideos (PC) son una estructura del cerebro situada en los ventrículos cerebrales, altamente conservada filogenética y ontogénicamente. Los PC se desarrollan temprano durante la embriogénesis y constituyen una barrera funcional en las primeras semanas de gestación. Están compuestos por tejido epitelial altamente vascularizado, cubiertos por microvellosidades y su función principal es la producción del líquido cefalorraquídeo (LCR). El sistema nervioso central se encuentra aislado y protegido por la barrera hematoencefálica (BHE) y por la barrera sangre-LCR (BSLCR). Mientras que la BHE se localiza al nivel de las células endoteliales en la microvasculatura del encéfalo, la BSLCR está formada por las células epiteliales de los plexos coroideos. La hipertensión arterial crónica induce una remodelación vascular para adaptarse a los valores elevados de presión arterial, con lo que se evita el riesgo de hiperperfusión ante presiones elevadas, pero se incrementa el riesgo de isquemia a presiones bajas; en cambio, en las personas normotensas la circulación cerebral se autorregula y el flujo sanguíneo permanece constante y se mantiene la integridad de la BHE. [...] (AU)


Introduction: The choroid plexuses, blood vessels, and brain barriers are closely related both in terms of morphology and function. Hypertension causes changes in cerebral blood flow and in small vessels and capillaries of the brain. This review studies the effects of high blood pressure (HBP) on the choroid plexuses and brain barriers. Development: The choroid plexuses (ChP) are structures located in the cerebral ventricles, and are highly conserved both phylogenetically and ontogenetically. The ChPs develop during embryogenesis, forming a functional barrier during the first weeks of gestation. They are composed of highly vascularised epithelial tissue covered by microvilli, and their main function is cerebrospinal fluid (CSF) production. The central nervous system (CNS) is protected by the blood-brain barrier (BBB) and the blood–CSF barrier (BCSFB). While the BBB is formed by endothelial cells of the microvasculature of the CNS, the BCSFB is formed by epithelial cells of the choroid plexuses. Chronic hypertension induces vascular remodelling. This prevents hyperperfusion at HBPs, but increases the risk of ischaemia at low blood pressures. In normotensive individuals, in contrast, cerebral circulation is self-regulated, blood flow remains constant, and the integrity of the BBB is preserved. Conclusions: HBP induces changes in the choroid plexuses that affect the stroma, blood vessels, and CSF production. HBP also exacerbates age-related ChP dysfunction and causes alterations in the brain barriers, which are more marked in the BCSFB than in the BBB. Brain barrier damage may be determined by quantifying blood S-100β and TTRm levels. (AU)


Assuntos
Humanos , Envelhecimento , Células Endoteliais , Hipertensão , Cérebro , Corioide
11.
Food Chem X ; 14: 100303, 2022 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-35450143

RESUMO

Fava bean (Vicia faba L.) is a high-protein crop consumed worldwide and is an exceptional plant-based protein source for human consumption. The present study evaluated in vitro nutritional properties of four different protein flours of fava bean: minimal processed flour (MPF), cooked flour (CF), non-polyphenol protein concentrate (NPP), and polyphenol-protein concentrate (PP). NPP showed the highest protein concentration of 94.39 ±â€¯0.76%. The heat treatment significantly increased the in vitro protein digestibility in CF (94.15 ±â€¯2.45%). NPP and PP showed the highest bioaccessibility, 29.85 ±â€¯1.88 and 33.19 ±â€¯1.65%, respectively, no significant differences. SDS-PAGE analysis revealed bioaccessible low molecular weight peptides (<15 kDa) and legumin and vicilin presence. In silico analysis of bioactive peptides of legumin and vicilin presented high occurrence frequencies of bioactivities, as angiotensin-converting enzyme-inhibitor and dipeptidyl peptidase III/IV inhibitor peptides. This study supports the use and further investigation of fava bean proteins for human nutrition.

12.
Acta Neuropathol Commun ; 10(1): 41, 2022 03 28.
Artigo em Inglês | MEDLINE | ID: mdl-35346374

RESUMO

Hydrocephalus is a distension of the ventricular system associated with ventricular zone disruption, reactive astrogliosis, periventricular white matter ischemia, axonal impairment, and corpus callosum alterations. The condition's etiology is typically attributed to a malfunction in classical cerebrospinal fluid (CSF) bulk flow; however, this approach does not consider the unique physiology of CSF in fetal and perinatal patients. The parenchymal fluid contributes to the glymphatic system, and plays a fundamental role in pediatric hydrocephalus, with aquaporin 4 (AQP4) as the primary facilitator of these fluid movements. Despite the importance of AQP4 in the pathophysiology of hydrocephalus, it's expression in human fetal life is not well-studied. This manuscript systematically defines the brain expression of AQP4 in human brain development under control (n = 13) and hydrocephalic conditions (n = 3). Brains from 8 postconceptional weeks (PCW) onward and perinatal CSF from control (n = 2), obstructive (n = 6) and communicating (n = 6) hydrocephalic samples were analyzed through immunohistochemistry, immunofluorescence, western blot, and flow cytometry. Our results indicate that AQP4 expression is observed first in the archicortex, followed by the ganglionic eminences and then the neocortex. In the neocortex, it is initially at the perisylvian regions, and lastly at the occipital and prefrontal zones. Characteristic astrocyte end-feet labeling surrounding the vascular system was not established until 25 PCW. We also found AQP4 expression in a subpopulation of glial radial cells with processes that do not progress radially but, rather, curve following white matter tracts (corpus callosum and fornix), which were considered as glial stem cells (GSC). Under hydrocephalic conditions, GSC adjacent to characteristic ventricular zone disruption showed signs of early differentiation into astrocytes which may affect normal gliogenesis and contribute to the white matter dysgenesis. Finally, we found that AQP4 is expressed in the microvesicle fraction (p < 0.01) of CSF from patients with obstructive hydrocephalus. These findings suggest the potential use of AQP4 as a diagnostic and prognostic marker of pediatric hydrocephalus and as gliogenesis biomarker.


Assuntos
Hidrocefalia , Substância Branca , Aquaporina 4/metabolismo , Astrócitos/metabolismo , Encéfalo/patologia , Líquido Cefalorraquidiano , Criança , Humanos , Hidrocefalia/patologia , Substância Branca/patologia
13.
Neurologia (Engl Ed) ; 2021 Sep 13.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-34531045

RESUMO

INTRODUCTION: The relationship between the entorhinal cortex and the hippocampus has been studied by different authors, who have highlighted the importance of grid cells, place cells, and the trisynaptic circuit in the processes that they regulate: the persistence of spatial, explicit, and recent memory and their possible impairment with ageing. OBJECTIVE: We aimed to determine whether older age causes changes in the size and number of grid cells contained in layer III of the entorhinal cortex and in the granular layer of the dentate gyrus of the hippocampus. METHODS: We conducted post-mortem studies of the brains of 6 individuals aged 56-87 years. The brain sections containing the dentate gyrus and the adjacent entorhinal cortex were stained according to the Klüver-Barrera method, then the Image J software was used to measure the individual neuronal area, the total neuronal area, and the number of neurons contained in rectangular areas in layer III of the entorhinal cortex and layer II of the dentate gyrus. Statistical analysis was subsequently performed. RESULTS: We observed an age-related reduction in the cell population of the external pyramidal layer of the entorhinal cortex, and in the number of neurons in the granular layer of the dentate gyrus. CONCLUSION: Our results indicate that ageing causes a decrease in the size and density of grid cells of the entorhinal cortex and place cells of the dentate gyrus.

14.
J Environ Manage ; 278(Pt 1): 111515, 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-33113396

RESUMO

The use of non-thermal plasma (NTP) generators in air processing systems and their duct networks to improve indoor air quality (IAQ) has grown considerably in recent years. This paper reviews the advantages and disadvantages of NTP generators for IAQ improvement in biological, chemical and particulate pollutant terms. Also, it assesses and compares the ability of a multipin corona discharge (MPCD) and a dielectric barrier discharge (DBD) generator to reduce the concentration of fine particulate matter (PM2.5) in recycled, unfiltered air in a refrigeration chamber. The MPCD generator was found to have a higher PM2.5 removal efficiency; also, it was faster in removing pollutants, used less energy, and produced much less ozone. The fact that the MPCD generator performed better was seemingly the result of its increased ion production mainly. NTP generators, however, cannot match air filtration media purifiers in this respect as the latter are much more effective in removing particles. Besides, NTP-based air purifying technology continues to be subject to a major drawback, namely: the formation of ozone as a by-product. In any case, the ozone generation was uncorrelated to ion emission when using different technologies.


Assuntos
Poluentes Atmosféricos , Poluição do Ar em Ambientes Fechados , Gases em Plasma , Poluentes Atmosféricos/análise , Poluição do Ar em Ambientes Fechados/análise , Monitoramento Ambiental , Habitação , Tamanho da Partícula , Material Particulado/análise
16.
Materials (Basel) ; 13(5)2020 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-32121197

RESUMO

Natural fiber-reinforced thermoplastic composites can be an alternative to mineral fiber-based composites, especially when economic and environment concerns are included under the material selection criteria. In recent years, the literature has shown how lignocellulosic fiber-reinforced composites can be used for a variety of applications. Nonetheless, the impact strength and the water uptake behavior of such materials have been seen as drawbacks. In this work, the impact strength and the water uptake of composites made of polypropylene reinforced with fibers from recycled newspaper have been researched. The results show how the impact strength decreases with the percentage of reinforcement in a similar manner to that of glass fiber-reinforced polypropylene composites as a result of adding a fragile phase to the material. It was found that the water uptake increased with the increasing percentages of lignocellulosic fibers due to the hydrophilic nature of such reinforcements. The diffusion behavior was found to be Fickian. A maleic anhydride was added as a coupling agent in order to increase the strength of the interface between the matrix and the reinforcements. It was found that the presence of such a coupling agent increased the impact strength of the composites and decreased the water uptake. Impact strengths of 21.3 kJ/m3 were obtained for a coupled composite with 30 wt % reinforcement contents, which is a value higher than that obtained for glass fiber-based materials. The obtained composites reinforced with recycled fibers showed competitive impact strength and water uptake behaviors in comparison with materials reinforced with raw lignocellulosic fibers. The article increases the knowledge on newspaper fiber-reinforced polyolefin composite properties, showing the competitiveness of waste-based materials.

17.
Oxid Med Cell Longev ; 2019: 3276958, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31285784

RESUMO

Alpha-lipoic acid (ALA) has been used as a dietary supplement at different doses in patients with diabetes mellitus type 2 (T2DM) due to its antioxidant, anti-inflammatory, and hypoglycemic effects. However, the reports on the effects of ALA are controversial. For this reason, the purpose of the present study was to determine the effect of 600 mg/day of ALA on the markers of oxidative stress (OxS) and inflammation and RAGE in older adults with T2DM. A quasiexperimental study was carried out with a sample of 135 sedentary subjects (98 women and 37 men) with a mean age of 64 ± 1 years, who all had T2DM. The sample was divided into three groups: (i) experimental group (EG) with 50 subjects, (ii) placebo group (PG) with 50 subjects, and control group (CG) with 35 subjects. We obtained the following measurements in all subjects (pre- and posttreatment): glycosylated hemoglobin (HbA1c), receptor for advanced glycation end products (RAGE), 8-isoprostane, superoxide dismutase (SOD), glutathione peroxidase (GPx), total antioxidant status (TAS), and inflammatory (CRP, TNF-α, IL-6, IL-8, and IL-10) markers. Regarding the effect of ALA on HbA1c, a decrease was observed in the EG (baseline 8.9 ± 0.2 vs. posttreatment 8.6 ± 0.3) and the PG (baseline 8.8 ± 0.2 vs. posttreatment 8.4 ± 0.3) compared to the CG (baseline 8.8 ± 0.3 vs. six months 9.1 ± 0.3) although the difference was not statistically significant (p < 0.05). There was a statistically significant decrease (p < 0.05) in the blood concentration of 8-isoprostane in the EG and PG with respect to the CG (EG: baseline 100 ± 3 vs. posttreatment 57 ± 3, PG: baseline 106 ± 7 vs. posttreatment 77 ± 5, and CG: baseline 94 ± 10 vs. six months 107 ± 11 pg/mL). Likewise, a statistically significant decrease (p < 0.05) in the concentration of the RAGE was found in the EG (baseline 1636 ± 88 vs. posttreatment 1144 ± 68) and the PG (baseline 1506 ± 97 vs. posttreatment 1016 ± 82) compared to CG (baseline 1407 ± 112 vs. six months 1506 ± 128). A statistically significant decrease was also observed in all markers of inflammation and in the activity of SOD and GPx in the CG with respect to the EG and PG. Our findings suggest that the administration of ALA at a dose of 600 mg/day for six months has a similar effect to that of placebo on oxidative stress, inflammation, and RAGE in older adults with T2DM. Therefore, higher doses of ALA should be tried to have this effect. This trial is registered with trial registration number ISRCTN13159380.


Assuntos
Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/metabolismo , Inflamação/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Receptor para Produtos Finais de Glicação Avançada/metabolismo , Ácido Tióctico/uso terapêutico , Idoso , Antioxidantes/metabolismo , Glicemia/metabolismo , Pressão Sanguínea/efeitos dos fármacos , Proteína C-Reativa/metabolismo , Cromatografia Líquida de Alta Pressão , Diabetes Mellitus Tipo 2/sangue , Ingestão de Energia/fisiologia , Feminino , Glutationa Peroxidase/sangue , Humanos , Inflamação/tratamento farmacológico , Masculino , Pessoa de Meia-Idade , Superóxido Dismutase/sangue , Ácido Tióctico/sangue
18.
J Neuropathol Exp Neurol ; 78(7): 641-647, 2019 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-31039249

RESUMO

The choroid plexus (ChP) is involved in the production of cerebrospinal fluid (CSF) and is intimately related to CSF physiopathology. Aquaporin-1 (AQP1) is the water channel directly implicated in CSF production and a potential therapeutic target in the management of CSF circulation disorders. Pathologies that present ventriculomegaly are associated with defective CSF turnover and AQPs are involved in both the production and reabsorption of CSF. This work examines the levels of AQP1 and its dynamics in ventriculomegaly conditions such as congenital hydrocephalus (communicating and obstructive) or type II lissencephaly versus control. We specifically address the expression of AQP1 in the CSF of 16 term-pregnancy infants where it was found to be significantly increased in obstructive cases when compared with communicating hydrocephalus or control patients. We also defined histologically the expression of AQP1 in the ChP from 6 nonsurvival preterm-pregnancy infants ranging ages between 20 and 25 gestational weeks in which AQP1 was mainly expressed at the apical pole of the ChP epithelium (ChPE) in control and lissencephalic patients. AQP1 expression from the Chiari malformation case showed an inverted polarity being expressed in the basal pole of the ChPE colocalizing with the glucose transporter 1 where this transporter is naturally located.


Assuntos
Aquaporina 1/biossíntese , Aquaporina 1/líquido cefalorraquidiano , Malformação de Arnold-Chiari/metabolismo , Malformação de Arnold-Chiari/patologia , Plexo Corióideo/metabolismo , Hidrocefalia/metabolismo , Hidrocefalia/patologia , Adulto , Biomarcadores/líquido cefalorraquidiano , Ventrículos Cerebrais/patologia , Feminino , Humanos , Recém-Nascido , Recém-Nascido Prematuro , Lisencefalia/patologia , Gravidez
19.
Mater Sci Eng C Mater Biol Appl ; 94: 1009-1019, 2019 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-30423682

RESUMO

Glibenclamide is an anti-hyperglycaemic drug that is commonly used for the treatment of type 2 diabetes mellitus and has promising new medical indications. However, this drug is associated with high rates of serious hypoglycaemic episodes as a result of its pharmacological activity. Administering the drug through controlled release delivery systems could reduce the incidence of these episodes. In this study, glibenclamide silica monolithic xerogel implants for subdermal application (GMSIx) were developed using the sol-gel technique for matrix synthesis with TEOS with different drying conditions (environmental, 60, 90, and 120 °C, which were named as GMSIE, GMSI60, GMSI90, and GMSI120, respectively). The inclusion of the drug in monoliths was monitored by DSC, FTIR, and PXRD. The effect of drying conditions on the morphology, moisture content, hardness, dosage uniformity, surface characteristics, and drug release mechanism of glibenclamide from the matrices was systematically investigated. Oral Glucose Tolerance Tests were performed with mice to evaluate the efficacy of the GMSI in maintaining blood glucose levels. Glibenclamide was completely included in a non-crystalline solid form in the matrixes. The moisture content, hardness, dosage uniformity, and surface characteristics depend on the drying conditions. The monolithic matrices showed a mesoporous surface with high surface area, and a narrower pore size distribution occurred for GMSI60. GMSIE and GMSI60 showed non-Fickian anomalous Korsmeyer-Peppas glibenclamide release kinetics. GMSI90 and GMSI120 showed controlled release of the drug through dissolution. When GMSI60 was administered to mice, glucose blood levels were effectively maintained despite a high oral glucose load in the animals, showing a sustained effect of the drug released from this new sol-gel drug delivery system.


Assuntos
Glibureto/uso terapêutico , Hiperglicemia/tratamento farmacológico , Implantes Experimentais , Transição de Fase , Dióxido de Silício/química , Animais , Preparações de Ação Retardada/administração & dosagem , Preparações de Ação Retardada/farmacologia , Preparações de Ação Retardada/uso terapêutico , Modelos Animais de Doenças , Glibureto/administração & dosagem , Glibureto/farmacologia , Umidade , Hiperglicemia/patologia , Cinética , Masculino , Camundongos , Porosidade , Padrões de Referência , Reprodutibilidade dos Testes , Espectroscopia de Infravermelho com Transformada de Fourier , Difração de Raios X
20.
Cells ; 7(11)2018 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-30428541

RESUMO

Aquaporin 1 (AQP1) and aquaporin 4 (AQP4) have been identified in the eye as playing an essential role in the formation of the aqueous humor along with the Na⁺/K⁺ ATPase pump. Different authors have described the relationship between blood pressure, aqueous humor production, and intraocular pressure with different conclusions, with some authors supporting a positive correlation between blood pressure and intraocular pressure while others disagree. The aim of this work was to study the effect of high blood pressure on the proteins involved in the production of aqueous humor in the ciliary body (CB) and iris. For this purpose, we used the eyes of spontaneously hypertensive rats (SHR) and their control Wistar-Kyoto rats (WKY). Immunofluorescence was performed in different eye structures to analyze the effects of hypertension in the expression of AQP1, AQP4, and the Na⁺/K⁺ ATPase α1 and α2 subunits. The results showed an increase in AQP1 and Na⁺/K⁺ ATPase α1 and a decrease in AQP4 and Na⁺/K⁺ ATPase α2 in the CB of SHR, while an increase in AQP4 and no significant differences in AQP1 were found in the iris. Therefore, systemic hypertension produced changes in the proteins implicated in the movement of water in the CB and iris that could influence the production rate of aqueous humor, which would be affected depending on the duration of systemic hypertension.

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