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1.
Nanomaterials (Basel) ; 13(9)2023 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-37177056

RESUMO

Several biochars were synthesized from olive stones and used as supports for TiO2, as an active semiconductor, and Pt as a co-catalyst (Pt/TiO2-PyCF and Pt/TiO2-AC). A third carbon-supported photocatalyst was prepared from commercial mesoporous carbon (Pt/TiO2-MCF). Moreover, a Pt/TiO2 solid based on Evonik P25 was used as a reference. The biochars used as supports transferred, to a large extent, their physical and chemical properties to the final photocatalysts. The synthesized catalysts were tested for hydrogen production from aqueous glycerol photoreforming. The results indicated that a mesoporous nature and small particle size of the photocatalyst lead to better H2 production. The analysis of the operational reaction conditions revealed that the H2 evolution rate was not proportional to the mass of the photocatalyst used, since, at high photocatalyst loading, the hydrogen production decreased because of the light scattering and reflection phenomena that caused a reduction in the light penetration depth. When expressed per gram of TiO2, the activity of Pt/TiO2-PyCF is almost 4-times higher than that of Pt/TiO2 (1079 and 273 mmol H2/gTiO2, respectively), which points to the positive effect of an adequate dispersion of a TiO2 phase on a carbonaceous support, forming a highly dispersed and homogeneously distributed titanium dioxide phase. Throughout a 12 h reaction period, the H2 production rate progressively decreases, while the CO2 production rate increases continuously. This behavior is compatible with an initial period when glycerol dehydrogenation to glyceraldehyde and/or dihydroxyacetone and hydrogen predominates, followed by a period in which comparatively slower C-C cleavage reactions begin to occur, thus generating both H2 and CO2.

2.
Nanomaterials (Basel) ; 13(4)2023 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-36839032

RESUMO

Hydrogen production is mainly based on the use of fossil fuels, but currently, many alternative routes are being developed, among which the photo-reforming of oxygenated organic compounds stands out. Recently, several studies have been carried out in order to develop new techniques to create bio-inspired TiO2 structures. One of these is 'biotemplating', a process that replicates a biological system in an inorganic TiO2-based structure. In this study, olive by-products-olive leaves-are valorized as a biotemplate for the synthesis of new Fe-TiO2- and Cu-TiO2-based photocatalysts with the aim of improving the replication of the leaf structure and enhancing hydrogen photoproduction. In conclusion, the incorporation of iron and copper decreases the band gap and increases the energetic disorder at the band edges. Moreover, it is verified by SEM and TEM that the metals are not found forming particles but are introduced into the formed TiO2 structure. The accuracy of the internal and external structure replication is improved with the incorporation of Fe in the synthesis, while the incorporation of Cu substantially improves the production of hydrogen, which is multiplied 14 times under UV light and 6 times under sunlight, as compared to a pure TiO2 structure.

3.
Front Microbiol ; 14: 1129721, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36846808

RESUMO

Nitrogen (N) and phosphorus (P) deficiencies are two of the most agronomic problems that cause significant decrease in crop yield and quality. N and P chemical fertilizers are widely used in current agriculture, causing environmental problems and increasing production costs. Therefore, the development of alternative strategies to reduce the use of chemical fertilizers while maintaining N and P inputs are being investigated. Although dinitrogen is an abundant gas in the atmosphere, it requires biological nitrogen fixation (BNF) to be transformed into ammonium, a nitrogen source assimilable by living organisms. This process is bioenergetically expensive and, therefore, highly regulated. Factors like availability of other essential elements, as phosphorus, strongly influence BNF. However, the molecular mechanisms of these interactions are unclear. In this work, a physiological characterization of BNF and phosphorus mobilization (PM) from an insoluble form (Ca3(PO4)2) in Azotobacter chroococcum NCIMB 8003 was carried out. These processes were analyzed by quantitative proteomics in order to detect their molecular requirements and interactions. BNF led to a metabolic change beyond the proteins strictly necessary to carry out the process, including the metabolism related to other elements, like phosphorus. Also, changes in cell mobility, heme group synthesis and oxidative stress responses were observed. This study also revealed two phosphatases that seem to have the main role in PM, an exopolyphosphatase and a non-specific alkaline phosphatase PhoX. When both BNF and PM processes take place simultaneously, the synthesis of nitrogenous bases and L-methionine were also affected. Thus, although the interdependence is still unknown, possible biotechnological applications of these processes should take into account the indicated factors.

5.
Int J Mol Sci ; 23(23)2022 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-36499740

RESUMO

Obesity and overweight are defined as abnormal fat accumulations. Adipose tissue consists of more than merely adipocytes; each adipocyte is closely coupled with the extracellular matrix. Adipose tissue stores excess energy through expansion. Obesity is caused by the abnormal expansion of adipose tissue as a result of adipocyte hypertrophy and hyperplasia. The process of obesity is controlled by several molecules, such as integrins, kindlins, or matrix metalloproteinases. In children with obesity, metabolomics studies have provided insight into the existence of unique metabolic profiles. As a result of low-grade inflammation in the system, abnormalities were observed in several metabolites associated with lipid, carbohydrate, and amino acid pathways. In addition, obesity and related hormones, such as leptin, play an instrumental role in regulating food intake and contributing to childhood obesity. The World Health Organization states that physical activity benefits the heart, the body, and the mind. Several noncommunicable diseases, such as cardiovascular disease, cancer, and diabetes, can be prevented and managed through physical activity. In this work, we reviewed pediatric studies that examined the molecular and hormonal control of obesity and the influence of physical activity on children with obesity or overweight. The purpose of this review was to examine some orchestrators involved in this disease and how they are related to pediatric populations. A larger number of randomized clinical trials with larger sample sizes and long-term studies could lead to the discovery of new key molecules as well as the detection of significant factors in the coming years. In order to improve the health of the pediatric population, omics analyses and machine learning techniques can be combined in order to improve treatment decisions.


Assuntos
Obesidade Infantil , Humanos , Criança , Obesidade Infantil/metabolismo , Exercício Físico/fisiologia , Sobrepeso/metabolismo , Adipócitos/metabolismo , Tecido Adiposo
6.
J Clin Med ; 11(19)2022 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-36233500

RESUMO

Hospitalized patients with COVID-19 are at increased risk of thrombosis, acute respiratory distress syndrome and death. The optimal dosage of thromboprophylaxis is unknown. The aim was to evaluate the efficacy and safety of tinzaparin in prophylactic, intermediate, and therapeutic doses in non-critical patients admitted for COVID-19 pneumonia. PROTHROMCOVID is a randomized, unblinded, controlled, multicenter trial enrolling non-critical, hospitalized adult patients with COVID-19 pneumonia. Patients were randomized to prophylactic (4500 IU), intermediate (100 IU/kg), or therapeutic (175 IU/kg) groups. All tinzaparin doses were administered once daily during hospitalization, followed by 7 days of prophylactic tinzaparin at discharge. The primary efficacy outcome was a composite endpoint of symptomatic systemic thrombotic events, need for invasive or non-invasive mechanical ventilation, or death within 30 days. The main safety outcome was major bleeding at 30 days. Of the 311 subjects randomized, 300 were included in the prespecified interim analysis (mean [SD] age, 56.7 [14.6] years; males, 182 [60.7%]). The composite endpoint at 30 days from randomization occurred in 58 patients (19.3%) of the total population; 19 (17.1 %) in the prophylactic group, 20 (22.1%) in the intermediate group, and 19 (18.5%) in the therapeutic dose group (p = 0.72). No major bleeding event was reported; non-major bleeding was observed in 3.7% of patients, with no intergroup differences. Due to these results and the futility analysis, the trial was stopped. In non-critically ill COVID-19 patients, intermediate or full-dose tinzaparin compared to standard prophylactic doses did not appear to affect the risk of thrombotic event, non-invasive ventilation, or mechanical ventilation or death. Trial RegistrationClinicalTrials.gov Identifier (NCT04730856). Edura-CT registration number: 2020-004279-42.

7.
Int J Mol Sci ; 23(16)2022 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-36012437

RESUMO

Denitrification consists of the sequential reduction of nitrate to nitrite, nitric oxide, nitrous oxide, and dinitrogen. Nitrous oxide escapes to the atmosphere, depending on copper availability and other environmental factors. Iron is also a key element because many proteins involved in denitrification contain iron-sulfur or heme centers. The NtrYX two-component regulatory system mediates the responses in a variety of metabolic processes, including denitrification. A quantitative proteomic analysis of a Paracoccus denitrificans NtrY mutant grown under denitrifying conditions revealed the induction of different TonB-dependent siderophore transporters and proteins related to iron homeostasis. This mutant showed lower intracellular iron content than the wild-type strain, and a reduced growth under denitrifying conditions in iron-limited media. Under iron-rich conditions, it releases higher concentrations of siderophores and displayes lower nitrous oxide reductase (NosZ) activity than the wild-type, thus leading to nitrous oxide emission. Bioinformatic and qRT-PCR analyses revealed that NtrYX is a global transcriptional regulatory system that responds to iron starvation and, in turn, controls expression of the iron-responsive regulators fur, rirA, and iscR, the denitrification regulators fnrP and narR, the nitric oxide-responsive regulator nnrS, and a wide set of genes, including the cd1-nitrite reductase NirS, nitrate/nitrite transporters and energy electron transport proteins.


Assuntos
Paracoccus denitrificans , Desnitrificação , Homeostase , Ferro/metabolismo , Nitratos/metabolismo , Óxido Nítrico/metabolismo , Nitritos/metabolismo , Óxido Nitroso/metabolismo , Paracoccus denitrificans/genética , Paracoccus denitrificans/metabolismo , Proteômica
8.
Mycoses ; 65(5): 517-525, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35262977

RESUMO

BACKGROUND: Invasive fungal infection, particularly intraabdominal candidiasis, exerts a negative impact on the outcome of pancreas transplant recipients (PTRs). Optimal antifungal prophylaxis in this context remains unclear. METHODS: We performed a single-centre retrospective study to compare the incidence of invasive candidiasis during the first 6 post-transplant months in a cohort of 218 PTRs over two periods in which different agents for antifungal prophylaxis were used: fluconazole (Fluco-Px) from March 1995 to June 2012, and micafungin followed by fluconazole (Mica-Px) from July 2012 to December 2018. RESULTS: A total of 152 and 66 PTRs received Fluco-Px and Mica-Px. Mean age was 39.7 ± 7.8 years, 56.4% (123/218) were males, and 85.3% (186/218) underwent simultaneous pancreas-kidney transplantation. Invasive candidiasis occurred in 21.7% (33/152) of PTRs under Fluco-Px compared to 24.2% (16/66) of those under Mica-Px (p-value = .681). Median time from transplantation to infection was 8 days (interquartile range [IQR]: 6-16) under Fluco-Px versus 6.5 (IQR: 3.3-15.8) under Mica-Px (p-value = .623). Non-albicans Candida species comprised 27.5% (11/40) and 25.0% (4/16) of episodes under Fluco-Px and Mica-Px respectively (p-value = .849). Surgical site infection was the most common form in both groups (82.5% [33/40] and 87.5% [14/16]; p-value = .954). Multivariable analysis identified cold ischaemia time of the pancreas and kidney grafts, surgical reintervention and insulin requirement after transplantation as risks factor for invasive candidiasis. CONCLUSION: This retrospective study did not reveal a significant benefit from the initial use of micafungin-based antifungal prophylaxis over fluconazole among PTRs in terms of invasive candidiasis.


Assuntos
Candidíase Invasiva , Transplante de Pâncreas , Adulto , Antifúngicos/uso terapêutico , Candida , Candidíase , Candidíase Invasiva/tratamento farmacológico , Feminino , Fluconazol/uso terapêutico , Humanos , Masculino , Micafungina , Pessoa de Meia-Idade , Pâncreas , Transplante de Pâncreas/efeitos adversos , Estudos Retrospectivos , Transplantados
10.
Sci Rep ; 11(1): 17276, 2021 08 26.
Artigo em Inglês | MEDLINE | ID: mdl-34446760

RESUMO

Denitrification is a respiratory process by which nitrate is reduced to dinitrogen. Incomplete denitrification results in the emission of the greenhouse gas nitrous oxide and this is potentiated in acidic soils, which display reduced denitrification rates and high N2O/N2 ratios compared to alkaline soils. In this work, impact of pH on the proteome of the soil denitrifying bacterium Paracoccus denitrificans PD1222 was analysed with nitrate as sole energy and nitrogen source under anaerobic conditions at pH ranging from 6.5 to 7.5. Quantitative proteomic analysis revealed that the highest difference in protein representation was observed when the proteome at pH 6.5 was compared to the reference proteome at pH 7.2. However, this difference in the extracellular pH was not enough to produce modification of intracellular pH, which was maintained at 6.5 ± 0.1. The biosynthetic pathways of several cofactors relevant for denitrification and nitrogen assimilation like cobalamin, riboflavin, molybdopterin and nicotinamide were negatively affected at pH 6.5. In addition, peptide representation of reductases involved in nitrate assimilation and denitrification were reduced at pH 6.5. Data highlight the strong negative impact of pH on NosZ synthesis and intracellular copper content, thus impairing active NosZ assembly and, in turn, leading to elevated nitrous oxide emissions.


Assuntos
Proteínas de Bactérias/metabolismo , Paracoccus denitrificans/metabolismo , Proteoma/metabolismo , Proteômica/métodos , Microbiologia do Solo , Proteínas de Bactérias/genética , Desnitrificação , Regulação Bacteriana da Expressão Gênica , Concentração de Íons de Hidrogênio , Nitratos/metabolismo , Nitritos/metabolismo , Nitrogênio/metabolismo , Óxido Nitroso/metabolismo , Oxirredutases/genética , Oxirredutases/metabolismo , Paracoccus denitrificans/genética , Proteoma/genética , Solo/química
11.
Nanomaterials (Basel) ; 11(4)2021 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-33917685

RESUMO

In this work, electroluminescence in Metal-Insulator-Semiconductors (MIS) and Metal-Insulator-Metal (MIM)-type structures was studied. These structures were fabricated with single- and double-layer silicon-rich-oxide (SRO) films by means of Hot Filament Chemical Vapor Deposition (HFCVD), gold and indium tin oxide (ITO) were used on silicon and quartz substrates as a back and front contact, respectively. The thickness, refractive indices, and excess silicon of the SRO films were analyzed. The behavior of the MIS and MIM-type structures and the effects of the pristine current-voltage (I-V) curves with high and low conduction states are presented. The structures exhibit different conduction mechanisms as the Ohmic, Poole-Frenkel, Fowler-Nordheim, and Hopping that contribute to carrier transport in the SRO films. These conduction mechanisms are related to the electroluminescence spectra obtained from the MIS and MIM-like structures with SRO films. The electroluminescence present in these structures has shown bright dots in the low current of 36 uA with a voltage of -20 V to -50 V. However, when applied voltages greater than -67 V with 270 uA, a full area with uniform blue light emission is shown.

12.
Materials (Basel) ; 13(17)2020 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-32872129

RESUMO

This article explores the effect of the synthetic method of titanium dioxide (TiO2)/C composites (physical mixture and the water-assisted/unassisted sol-gel method) on their photocatalytic activity for hydrogen production through glycerol photoreforming. The article demonstrates that, apart from a high surface area of carbon and the previous activation of its surface to favor titania incorporation, the appropriate control of titania formation is crucial. In this sense, even though the amount of incorporated titania was limited by the saturation of carbon surface groups (in our case, ca. 10 wt.% TiO2), the sol-gel process without water addition seemed to be the best method, ensuring the formation of small homogeneously-distributed anatase crystals on mesoporous carbon. In this way, a ca. 110-fold increase in catalyst activity compared to Evonik P25 (expressed as hydrogen micromole per grams of titania) was achieved.

13.
Molecules ; 25(12)2020 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-32630602

RESUMO

The present paper investigates the feasibility of using acetone (ACE) in triple blends with fossil diesel (D) and straight vegetable oils (SVOs) as alternative fuel for diesel engines. In this respect, ACE is selected as an oxygenated additivedue to its favorable propertiesto be mixed with vegetable oils and fossil diesel. In fact, the very low kinematic viscosity allows reduces the high viscosity of SVOs. ACE's oxygen content, low autoignition temperature, and very low cloud point and pour point values highlight its possibilities as an additive in D/ACE/SVO triple blends. Moreover, ACE can be produced through a renewable biotechnological process, an acetone-butanol-ethanol (ABE) fermentation from cellulosic biomass. The SVOs tested were castor oil (CO), which is not suitable for human consumption, and sunflower oil (SO), used as a standard reference for waste cooking oil. The viscosity measurement of the ACE/SVO double blend was considered crucial to choose the optimum proportion, which better fulfilled the specifications established by European standard EN 590. Moreover, some of the most significant physicochemical properties of D/ACE/SVO triple blends, such as kinematic viscosity, cloud point, pour point, and calorific value, were determined to assess their suitability as fuels. The blends were evaluated in a conventional diesel generator through the study of the following parameters: engine power, smoke emissions, and fuel consumption. Despite the low calorific value of ACE limits its ratio in the mixtures due to engine knocking problems, the experimental results reveal an excellent performance for the blends containing up to 16-18% of ACE and 22-24% of SVO. These blends produce similar engine power as to fossil diesel, but with slightly higher fuel consumption. Considerable reductions in emissions of air pollutants, as well as excellent cold flow properties are also obtained with these triple blends. In summary, the use of these biofuels could achieve a substitution of fossil diesel up to 40%, independently on the SVO employed.


Assuntos
Acetona/química , Biocombustíveis/análise , Óleo de Rícino/química , Gasolina/análise , Óleos de Plantas/química , Óleo de Girassol/química , Emissões de Veículos/análise , Humanos
14.
Nanomaterials (Basel) ; 10(6)2020 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-32486324

RESUMO

Olive leaves (by-product from olive oil production in olive mills) were used as biotemplates to synthesize a titania-based artificial olive leaf (AOL). Scanning electron microscopy (SEM) images of AOL showed the successful replication of trichomes and internal structure channels present in olive leaves. The BET surface area of AOL was 52 m2·g-1. X-ray diffraction (XRD) and Raman spectra revealed that the resulting solid was in the predominantly-anatase crystalline form (7.5 nm average particle size). Moreover, the synthesis led to a red-shift in light absorption as compared to reference anatase (gap energies of 2.98 and 3.2 eV, respectively). The presence of surface defects (as evidenced by X-ray photoelectron spectroscopy, XPS, and electron paramagnetic resonance spectroscopy, EPR) and doping elements (e.g., 1% nitrogen, observed by elemental analysis and XPS) could account for that. AOL was preliminarily tested as a catalyst for hydrogen production through glycerol photoreforming and exhibited an activity 64% higher than reference material Evonik P25 under solar irradiation and 144% greater under ultraviolet radiation, (under voltage) UV.

15.
Nanomaterials (Basel) ; 10(2)2020 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-32012926

RESUMO

Porous Si-SiO2 UV microcavities are used to modulate a broad responsivity photodetector (GVGR-T10GD) with a detection range from 300 to 510 nm. The UV microcavity filters modified the responsivity at short wavelengths, while in the visible range the filters only attenuated the responsivity. All microcavities had a localized mode close to 360 nm in the UV-A range, and this meant that porous Si-SiO2 filters cut off the photodetection range of the photodetector from 300 to 350 nm, where microcavities showed low transmission. In the short-wavelength range, the photons were absorbed and did not contribute to the photocurrent. Therefore, the density of recombination centers was very high, and the photodetector sensitivity with a filter was lower than the photodetector without a filter. The maximum transmission measured at the localized mode (between 356 and 364 nm) was dominant in the UV-A range and enabled the flow of high energy photons. Moreover, the filters favored light transmission with a wavelength from 390 nm to 510 nm, where photons contributed to the photocurrent. Our filters made the photodetector more selective inside the specific UV range of wavelengths. This was a novel result to the best of our knowledge.

16.
Sci Rep ; 10(1): 2220, 2020 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-32041997

RESUMO

Obtaining silicon-based photonic-structures in the ultraviolet range would expand the wavelength bandwidth of silicon technology, where it is normally forbidden. Herein, we fabricated porous silicon microcavities by electrochemical etching of alternating high and low refraction index layers; and were carefully subjected to two stages of dry oxidation at 350 °C for 30 minutes and 900 °C, with different oxidation times. In this way, we obtained oxidized porous silicon that induces a shift of a localized mode in the ultraviolet region. The presence of Si-O-Si bonds was made clear by FTIR absorbance spectra. High-quality oxidized microcavities were shown by SEM, where their mechanical stability was clearly visible. We used an effective medium model to predict the refractive index and optical properties of the microcavities. The model can use either two or three components (Si, SiO2, and air). The latter predicts that the microcavities are made almost completely of SiO2, implying less photon losses in the structure. The theoretical photonic-bandgap structure and localized photonic mode location showed that the experimental spectral peaks within the UV photonic bandgap are indeed localized modes. These results support that our oxidation process is very advantageous to obtain complex photonic structures in the UV region.

17.
Rev. neurol. (Ed. impr.) ; 69(2): 77-86, 16 jul., 2019. ilus
Artigo em Espanhol | IBECS | ID: ibc-184018

RESUMO

Introducción. La parálisis cerebral se define como un grupo de trastornos del desarrollo del movimiento y la postura que limitan la actividad de la persona, que se deben a alteraciones no progresivas que se produjeron en el cerebro fetal o infantil en desarrollo en los primeros años de vida y que se acompaña con frecuencia de epilepsia, alteraciones cognitivas, sensoriales, de la comunicación o el comportamiento. La parálisis cerebral se ha mostrado en la literatura, el cine y la televisión, y este estudio tiene por objetivo conocer cómo se ha representado en estos medios. Desarrollo. La parálisis cerebral se ha representado en la literatura, el cine y la televisión de manera exhaustiva y con mayor o menor acierto. Se ha mostrado la sintomatología, las vivencias de pacientes, familiares y cuidadores, los tratamientos, los productos de apoyo, las barreras arquitectónicas o las relaciones sociales y laborales. En ocasiones, la representación se ha realizado de forma muy ajustada a la realidad, mientras que en otros casos se han amplificado los aspectos más dramáticos para dar consistencia a la trama. Conclusiones. La parálisis cerebral se ha representado ampliamente en obras de ficción y testimonio, cómics, películas, cortometrajes, documentales y series de televisión, en ocasiones de manera muy realista, mientras que en otras se ha podido contribuir a incrementar el estigma ofreciendo una visión distorsionada de la realidad, pero que en cualquier caso han contribuido a dar visibilidad a este cuadro patológico


Introduction. Cerebral palsy is defined as a group of developmental disorders affecting movement and posture that limit a person's activity. They due to non-progressive alterations that occurred in the developing foetal or infant brain in the early years of life and are often accompanied by epilepsy and cognitive, sensory, communication or behavioural disorders. Cerebral palsy has been portrayed in literature, cinema and television, and this study aims to explore how it has been represented in these media. Development. Cerebral palsy has frequently been represented in literature, cinema and television and with varying degrees of realism. The symptoms, the experiences of patients, relatives and caregivers, treatments, supporting products, architectural barriers or social and labour relations have all been portrayed. Sometimes they have been represented in a way that is very close to reality, while in other cases the most dramatic aspects have been amplified to add to the plot. Conclusions. Cerebral palsy has been widely represented in works of fiction and testimonies, comics, films, short films, documentaries and television series, sometimes in a very realistic way, while in others it has been done in a way that may increase the stigma surrounding this condition by offering a distorted vision of reality. Nevertheless, in any event they have helped to make this condition more visible


Assuntos
Humanos , Medicina na Literatura , Filmes Cinematográficos , Televisão , Paralisia Cerebral
18.
Ann Hepatol ; 18(2): 345-353, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31060976

RESUMO

INTRODUCTION AND AIM: Intake of a high-carbohydrate, low-protein diet (HCD/LPD) during pregnancy promotes metabolic disturbances. It has been suggested that liver function during pregnancy contributes to the synthesis of proteins necessary for fetal development during this stage. The liver is a site of response to the synthesis of macronutrients such as proteins. However, it is unknown how HCD/LPD is associated with modifications to the amino acid profiles and hepatic alterations in the maternal environment during pregnancy. MATERIALS AND METHODS: A transverse longitudinal study was done in primiparous mothers during gestation (G) (G1 day 1, G5 day 5, G15 day 15, and G20 day 20). Histological analysis was used to assess hepatic alterations, and amino acid profiles in the liver were analyzed with high performance liquid chromatography (HPLC). Food and water intake was quantified, and peripheral biochemical indicators in serum were measured. RESULTS: Mothers with HCD/LPD had increased micro and macro vesicles of fat, necrosis, and inflammation in the liver on G5. The total concentration of hepatic amino acids increased by 40% on G1, 17% on G5, and 25% on G15; and, there was a 12% decrease on G20. The following increases were observed in the liver on G1: arginine 68%, histidine 75%, alanine 18%, methionine 71%, and phenylalanine 51% (p>0.05); on G5: arginine 12%, methionine 34%, and phenylalanine 83% (p>0.05); on G15: arginine and phenylalanine 66%, tryptophan 81% and histidine 60.4% (p>0.05); and on G20: arginine 32% (p>0.05). No weight loss, changes in food consumption, or hepatomegaly occurred. CONCLUSIONS: HCD/LPD during pregnancy in primiparous mothers may promote development of fat vesicles. Possibly, this condition causes metabolic adaptations and nitrogen management reflected in decreased levels of serum urea and altered amino acid profiles in the liver.


Assuntos
Aminoácidos/metabolismo , Fenômenos Fisiológicos da Nutrição Animal , Dieta com Restrição de Proteínas , Carboidratos da Dieta/metabolismo , Proteínas Alimentares/metabolismo , Fígado/metabolismo , Fenômenos Fisiológicos da Nutrição Materna , Adaptação Fisiológica , Aminoácidos/administração & dosagem , Aminoácidos/toxicidade , Ração Animal , Animais , Dieta com Restrição de Proteínas/efeitos adversos , Carboidratos da Dieta/administração & dosagem , Carboidratos da Dieta/toxicidade , Proteínas Alimentares/administração & dosagem , Proteínas Alimentares/toxicidade , Feminino , Idade Gestacional , Metabolismo dos Lipídeos , Fígado/patologia , Estado Nutricional , Valor Nutritivo , Gravidez , Ratos Wistar , Ureia/sangue
19.
Nanomaterials (Basel) ; 9(4)2019 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-30986962

RESUMO

The influence of boron, tungsten and molybdenum modifiers on zirconia-based Pt catalyst was studied for glycerol valorization. Zirconia modified supports were prepared by impregnation of ZrO2 with either boric, silicontungstic or phosphomolybdic acids to obtain supports with enhanced Brönsted acidic properties. The modified supports were subsequently impregnated with chloroplatinic acid to obtain Pt-based catalysts. Pt incorporation resulted in the increase in Lewis acidity of the solids, being more significant for the Pt//W/ZrO2 catalyst. Reduced Pt catalysts were tested for the liquid-phase glycerol hydrogenolysis, observing a synergistic effect between catalyst acid sites and metal function that proved to be crucial in glycerol hydrogenolysis. The Pt//W/ZrO2 catalyst was the most active catalyst in this reaction, being the only leading to 1,3-PDO (45% sel., 160 °C) while Pt//Mo/ZrO2 is the best option for 1,2-PDO (49% sel., 180 °C). Reusability studies carried out for Pt//W/ZrO2 showed that catalytic activity dropped after the first use, remaining constant for the second and subsequent ones. Selectivity to reaction products also changes during reuses. Therefore, the selectivity to 1,2 PDO increases in the first reuse in detriment to the selectivity to n-propanol whereas the selectivity to 1,3-PDO remains constant along the uses. This behavior could be associated to the lixiviation of W species and/or catalyst fouling during reaction runs.

20.
Rev. neurol. (Ed. impr.) ; 67(2): 63-70, 15 jul., 2018. tab
Artigo em Espanhol | IBECS | ID: ibc-174871

RESUMO

Introducción. Las distrofias musculares son enfermedades hereditarias, producidas por una mutación genética, lentas o rápidamente progresivas, que afectan fundamentalmente a la musculatura estriada. Existen diversas formas clínicas, y las más frecuentes son la distrofia muscular de Duchenne y la distrofia muscular de Becker. Objetivo. Analizar cómo se han representado las distrofias musculares en la literatura, el cine y la televisión. Desarrollo. La distrofia muscular ha sido reflejada en la literatura, el cine y la televisión. En algunos casos sólo se menciona, en otros tiene un papel secundario en la trama y en otros es un personaje principal el que sufre la enfermedad. Generalmente se hace referencia a la enfermedad de Duchenne, y con menos frecuencia a la de Becker, aunque en algunos casos sólo se menciona que el paciente presenta distrofia muscular, sin especificar a qué variedad clínica pertenece. Podemos encontrar obras de testimonio, novelas, cómics, largometrajes de ficción, documentales, cortos y programas televisivos que pretenden dar a conocer la enfermedad y sus implicaciones, y concienciar a la población sobre la necesidad de invertir recursos en la investigación. Conclusiones. La distrofia muscular ha sido representada con realismo en la literatura, el cine y la televisión, y la distrofia muscular de Duchenne es la variedad clínica que se ha mostrado más habitualmente. Se han reflejado los síntomas, la evolución, el pronóstico, el papel de la familia y los cuidadores, la sexualidad, los tratamientos paliativos, el espíritu de superación, y la necesidad de concienciar a la sociedad y de invertir más recursos en investigación


Introduction. Muscular dystrophies are inherited disorders, produced by a genetic mutation, with a slow or rapid progression, that basically affect striated muscle tissue. There are several clinical forms, the most frequent being Duchenne's muscular dystrophy and Becker muscular dystrophy. Aim. To analyse how muscular dystrophies have been portrayed in literature, cinema and television. Development. Muscular dystrophy is a disorder that has been reflected in literature, cinema and television. In some cases it is only mentioned, sometimes it plays a secondary role in the plot, and in others it is the lead character who suffers from the disease. In general, reference is made to Duchenne's disease and, albeit less frequently, to Becker muscular dystrophy, although in some cases the patient is just said to be suffering from muscular dystrophy, without specifying what clinical variety it belongs to. Testimonials, novels, comics, fiction films, documentaries, short films and television programmes have all been produced with the aim of making the disease and its implications more widely known, as well as making the public aware of the need to invest resources in research. Conclusions. Muscular dystrophy has been portrayed quite realistically in literature, cinema and television, and Duchenne's muscular dystrophy is the clinical variety that has been shown most often. Aspects that have been reflected include its symptoms, progression, prognosis, the role of the family and caregivers, sexuality, palliative care, patients' will to overcome difficulties and the need to raise society's awareness of the condition and to invest more resources in research


Assuntos
Humanos , História do Século XIX , História do Século XX , História do Século XXI , Distrofias Musculares/epidemiologia , Distrofias Musculares/história , Medicina na Literatura , Filmes Cinematográficos , Televisão , Distrofia Muscular de Duchenne/epidemiologia , Prognóstico , Neurologia , Família , Cuidadores , Sexualidade , Cuidados Paliativos , História da Medicina
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