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1.
J Clin Med ; 13(3)2024 Feb 02.
Artículo en Inglés | MEDLINE | ID: mdl-38337582

RESUMEN

BACKGROUND: Despite medical advances, individuals with cerebral palsy (CP) face significant respiratory challenges, leading to heightened hospitalization rates and early mortality among this population. We hypothesize that integrating supplementary respiratory therapy into standard rehabilitation will result in significant improvements in pulmonary function, enhanced respiratory muscle strength, and an overall increase in the quality of life among pediatric patients with CP. METHODS: A systematic search of literature across five databases was conducted, and random-effects meta-analyses were performed to assess the impact of supplementary respiratory therapy on (a) pulmonary function: forced vital capacity (FVC), forced expiratory volume in 1 s (FEV1), FVC/FEV1 ratio, peak expiratory flow (PEF), and (b) respiratory muscle strength: maximal inspiratory and expiratory pressure (MIP, MEP), and (c) quality of life. Certainty of evidence was determined by the GRADE assessment. RESULTS: Analysis of data from 11 eligible randomized controlled trials revealed clinically meaningful changes in pulmonary function. We found a relevant mean difference (MD) in absolute PEF of 0.50 L/s (95% confidence interval (CI): 0.19; 0.82 p = 0.0107). The certainty of the evidence ranged from moderate to high. CONCLUSIONS: This study presents current evidence on the impact of various supplementary respiratory therapies for CP patients classified under gross motor function classification level I-IV, demonstrating clinically meaningful improvements in pulmonary function and respiratory muscle strength. These improvements suggest the potential for an enhanced quality of life. Our findings hold the promise of serving as a foundational reference for potential revisions to conventional rehabilitation care, incorporating supplementary respiratory therapy.

2.
Child Adolesc Psychiatry Ment Health ; 17(1): 124, 2023 Oct 27.
Artículo en Inglés | MEDLINE | ID: mdl-37891679

RESUMEN

OBJECTIVE: This study aimed to evaluate the association between the location (supratentorial or infratentorial) of brain tumors and the development of depression and anxiety in childhood cancer survivors. Understanding the risk factors for the development of depression and anxiety disordersin these patients is crucial for early diagnosis and successful treatment. METHODS: The meta-analysis included articles that listed patients diagnosed with an intracranial tumor before the age of 18 years, provided the location of the tumor, had exact data on the prevalence of anxiety and depression, or measured these disorders using different assessment tools. The search was conducted in five different databases (MEDLINE, Embase, Web of Science, Scopus, and Cochrane Library). Risk of bias was assessed using QUIPS-2. Outcome measures used were prevalences and standardized means. RESULTS: The analysis included 42 eligible articles with a total number of 1071 patients. Relevant articles were cohort studies, cross-sectional studies, and case series. Based on the available data infratentorial brain tumor survivors had significantly higher scores on various assessment tools measuring anxiety (MRAW (raw mean scores): 36.24 [CI (confidence interval): 28.81-43.67]; versus MRAW: 23.21 (CI 0.91-45.51); p = 0.02, and depression (MRAW: 27.57 (CI 14.35-40.78) versus MRAW: 13.84 (CI 11.43-16.26); p < 0.01. CONCLUSION: Childhood infratentorial cancer survivors have more impairments in terms of depression and anxiety; these children and adults should be monitored more frequently and may require closer follow-up on their mental health. The main limitation of our study originates from the lack of data on follow-up times used by different studies.

3.
Materials (Basel) ; 16(2)2023 Jan 04.
Artículo en Inglés | MEDLINE | ID: mdl-36676235

RESUMEN

Anionic surfactants, such as sodium linear alkylbenzene sulfonates (NaLAS), are utilized in various fields, including industry, household, and agriculture. The efficiency of their use in aqueous environments is significantly affected by the presence of cations, Ca2+ and Mg2+ in particular, as they can decrease the concentration of the surfactant due to precipitation. To understand cation-sulfonate interactions better, we study both NaLAS colloidal solutions in the presence of CaCl2 and precipitates forming at higher salt concentrations. Upon addition of CaCl2, we find the surface tension and critical micelle concentration of NaLAS to decrease significantly, in line with earlier findings for alkylbenzylsulfonates in the presence of divalent cations. Strikingly, an increase in the surface tension is discernible above 0.6 g L-1 NaLAS, accompanied by the decrease of apparent micelle sizes, which in turn gives rise to transparent systems. Thus, there appears to be a second critical concentration indicating another micellar equilibrium. Furthermore, the maximum salt tolerance of the surfactant is 0.1 g L-1 Ca2+, above which rapid precipitation occurs yielding sparingly soluble CaLAS2∙2H2O.

4.
J Colloid Interface Sci ; 632(Pt B): 260-270, 2023 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-36427422

RESUMEN

Tannic acid (TA) and glutathione (GSH) are important molecular antioxidants against reactive oxygen species. Their efficiency is limited by low solubility and high sensitivity, which may be solved by confinement in composite materials. Here, effect of immobilization of these antioxidants on their radical scavenging activity was investigated using layered double hydroxide (LDH) nanoparticles as hosts. Different preparation methods were applied to build composite systems leading to variations in the molecular orientation of both TA and GSH on the surface or among the layers of LDHs. Systematic combination of spectroscopy (FT-IR, Raman, UV-VIS-NIR-DRS), diffraction (XRD) and microscopy (SEM) methods revealed perpendicular or parallel orientation of TA on the surface of LDH depending on the preparation approach applied. Immobilization of GSH protected the antioxidant molecules from degradation. Radical scavenging tests evidenced that the activity of the antioxidants strongly depends on the molecular orientation. The LDH supported GSH and TA proved as durable and reusable antioxidant agents to be applied as radical scavengers in medical therapies or in industrial processes.


Asunto(s)
Antioxidantes , Glutatión , Antioxidantes/farmacología , Espectroscopía Infrarroja por Transformada de Fourier , Taninos , Especies Reactivas de Oxígeno
5.
Materials (Basel) ; 14(17)2021 Aug 27.
Artículo en Inglés | MEDLINE | ID: mdl-34500969

RESUMEN

The synthesis of the copper-poor and aluminum-rich layered double hydroxides (LDHs) of the CuAl4 type was optimized in detail in this work, by applying an intense mechanochemical treatment to activate the gibbsite starting reagent. The phase-pure forms of these LDHs were prepared for the first time; using copper nitrate and perchlorate salts during the syntheses turned out to be the key to avoiding the formation of copper hydroxide sideproducts. Based on the use of the optimized syntheses parameters, the preparation of layered triple and multiple hydroxides was also attempted using Ni(II), Co(II), Zn(II) and even Mg(II) ions. These studies let us identify the relative positions of the incorporating cations in the well-known selectivity series as Ni2+ >> Cu2+ >> Zn2+ > Co2+ >> Mg2+. The solids formed were characterized by using powder X-ray diffractometry, UV-Vis diffuse reflectance spectroscopy, Fourier-transform infrared spectroscopy, thermogravimetric analysis and scanning electron microscopy. The catalytic potential of the samples was investigated in carbon monoxide oxidation reactions at atmospheric pressure, supported by an in situ diffuse reflectance infrared spectroscopy probe. All solids proved to be active and the combination of the nickel and cobalt incorporation (which resulted in a NiCoAl8 layered triple hydroxide) brought outstanding benefits regarding low-temperature oxidation and increased carbon monoxide conversion values.

6.
Molecules ; 25(21)2020 Oct 29.
Artículo en Inglés | MEDLINE | ID: mdl-33138128

RESUMEN

In hydrometallurgical processing and acidic wastewater treatment, one of the neutralizing agents employed is MgO or Mg(OH)2. At the end of this process, the resulting solution, which is rich in SO42- and Mg2+ is treated with lime to remove (or minimize the amount) of these ions via the precipitation of Mg(OH)2 and CaSO4·2H2O (gypsum). In our work, an attempt was made to separate the two solids by increasing the induction time of the gypsum precipitation, thus regenerating relatively pure Mg(OH)2 which could be reused in wastewater treatments or hydrometallurgical processing circuits, and in this way, significantly enhancing the economic viability of the process. During our experiments, the reaction of an MgSO4 solution with milk of lime prepared from quicklime was studied. The effects of a range of organic additives, which can slow down the precipitation of gypsum have been assessed. The process was optimized for the most promising inhibiting agent-that is, the citrate ion. The reactions were continuously monitored in situ by conductometric measurements with parallel monitoring of solution pH and temperature. ICP-OES measurements were also carried out on samples taken from the reaction slurry. The composition of the precipitating solids at different reaction times was established by powder XRD and their morphology by SEM. Finally, experiments were carried out to locate the additive after the completion of the precipitation reaction to get information about its potential reuse.


Asunto(s)
Sulfato de Calcio/química , Precipitación Química , Ácido Cítrico/química , Hidróxido de Magnesio/aislamiento & purificación , Aguas Residuales/química , Hidróxido de Magnesio/química , Contaminantes Químicos del Agua
7.
Molecules ; 25(20)2020 Oct 14.
Artículo en Inglés | MEDLINE | ID: mdl-33066653

RESUMEN

In the present work, the structure and thermal stability of Ca-Al mixed-metal compounds, relevant in the Bayer process as intermediates, have been investigated. X-ray diffraction (XRD) measurements revealed the amorphous morphology of the compounds, which was corroborated by SEM-EDX measurements. The results of ICP-OES and UV-Vis experiments suggested the formation of three possible ternary calcium aluminum heptagluconate (Ca-Al-Hpgl) compounds, with the formulae of CaAlHpgl(OH)40, Ca2AlHpgl2(OH)50 and Ca3Al2Hpgl3(OH)90. Additional IR and Raman experiments revealed the centrally symmetric arrangement of heptagluconate around the metal ion. The increased thermal stability was demonstrated by thermal analysis of the solids and confirmed our findings.


Asunto(s)
Aluminio/química , Calcio/química , Gluconatos/química , Cristalografía por Rayos X , Microscopía Electrónica de Rastreo , Estructura Molecular , Espectrometría por Rayos X , Espectrofotometría Infrarroja , Espectroscopía Infrarroja por Transformada de Fourier , Espectrometría Raman , Temperatura , Termogravimetría
8.
Nanomaterials (Basel) ; 10(4)2020 Mar 28.
Artículo en Inglés | MEDLINE | ID: mdl-32231111

RESUMEN

In the experimental work leading to this contribution, the parameters of the ultrasound treatment (temperature, output power, emission periodicity) were varied to learn about the effects of the sonication on the crystallization of Ni nanoparticles during the hydrazine reduction technique. The solids were studied in detail by X-ray diffractometry, dynamic light scattering, thermogravimetry, specific surface area, pore size analysis, temperature-programmed CO2/NH3 desorption and scanning electron microscopy. It was found that the thermal behaviour, specific surface area, total pore volume and the acid-base character of the solids were mainly determined by the amount of the nickel hydroxide residues. The highest total acidity was recorded over the solid under low-power (30 W) continuous ultrasonic treatment. The catalytic behaviour of the nanoparticles was tested in a Suzuki-Miyaura cross-coupling reaction over five samples prepared in the conventional as well as the ultrasonic ways. The ultrasonically prepared catalysts usually performed better, and the highest catalytic activity was measured over the nanoparticles prepared under low-power (30 W) continuous sonication.

9.
Ultrason Sonochem ; 55: 165-173, 2019 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-30853533

RESUMEN

The output power (30-150 W) and the periodicity (20-100%) of ultrasound emission were varied in a wide range to regulate and improve the crystallization process in the commonly used co-precipitation technique of chloride-intercalated CaFe-layered double hydroxides. The influence of ultrasound irradiation on the as-prepared materials was studied by X-ray diffractometry, dynamic light scattering, UV-Vis-NIR diffuse reflectance spectroscopy, specific surface area measurement, pore size analysis, ion-selective electrode potentiometric investigations and thermogravimetry. Additionally, structural alterations due to heat treatment at various temperatures were followed in detail by Fourier-transform infrared and X-ray absorption spectroscopies as well as scanning electron microscopy. The ultrasonic treatment was capable of controlling the sizes of primarily formed (from 19 nm to 30 nm) as well as the aggregated (secondary) particles (between 450 nm and 700 nm), and thus modifying their textural parameters and enhancing the incorporation of chloride anions into the interlamellar space. For the first time, the optical energy gap of CaFe-LDH was reported here depending on the nature of applied stirring (4.18-4.34 eV). The heat-treatment investigations revealed that the layered structure was stabile until 200 °C, even at the atomic level.

10.
J Nanosci Nanotechnol ; 19(1): 389-394, 2019 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-30327046

RESUMEN

Samples of copper powder was milled with varied grinding frequencies in the presence of various organic agents (oleylamine, ethylene glycol or dimethyl sulfoxide) or without additives. The effects of experimental conditions were investigated by X-ray diffractometry, scanning electron microscopy and dynamic light scattering measurements. The aggregation of particles were supressed by added organics. The catalytic activities of the variously treated samples were measured in the Ullmanntype reaction of iodobenzene and 1H-pyrazole.

11.
J Nanosci Nanotechnol ; 19(1): 453-458, 2019 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-30327055

RESUMEN

The hydrazine reduction method was applied for the synthesis of nickel nanoparticles without using inert atmosphere and added surface active agents. The effect of the preparation temperature and the chemical quality of the metal sources as well as the solvents were studied. The generation of nanoparticles were studied primarily by X-ray diffractometry, but scanning and transmission electron microscopies as well as dynamic light scattering measurements were also used for the better understanding of the nanoparticles behaviour. The elevation of temperature was the key point in transforming Ni(OH)2 into metallic nickel. By selecting the metal source, the obtained crystallite sizes could be tailored between 7 nm and 15 nm; however, the SEM and DLS measurements revealed significant agglomeration resulting in aggregates with spherical or Ni(OH)2 resembling morphologies depending on the solvent used. The catalytic activities of the nanoparticles prepared were tested and compared in a Suzuki-Miyaura cross-coupling reaction.

12.
Ultrason Sonochem ; 40(Pt A): 853-860, 2018 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-28946496

RESUMEN

An ultrasonically-enhanced mechanochemical method was developed to synthesize CaFe-layered double hydroxides (LDHs) with various interlayer anions (CO32-, NO3-, ClO4-, N3-, F-, Cl-, Br- and I-). The duration of pre-milling and ultrasonic irradiation and the variation of synthesis temperature in the wet chemical step were investigated to obtain the optimal parameters of preparation. The main method to characterize the products was X-ray diffractometry, but infrared and synchrotron-based X-ray absorption spectroscopies as well as thermogravimetric measurements were also used to learn about fine structural details. The synthesis method afforded successful intercalation of the anions, among others the azide anion, a rarely used counter ion providing a system, which enables safe handling the otherwise highly reactive anion. The X-ray absorption spectroscopic measurements revealed that the quality of the interlayered anions could modulate the spatial arrangement of the calcium ions around the iron(III) ions, but only in the second coordination sphere.

13.
Ultrason Sonochem ; 32: 173-180, 2016 09.
Artículo en Inglés | MEDLINE | ID: mdl-27150758

RESUMEN

The combination of mechanochemical and ultrasonic treatment was applied to synthesize CaAlFe-layered triple hydroxides with carbonate or chloride anions in the interlamellar space. The optimal parameters of the preparation were explored by altering the initial ratio of the metal ions and the temperature of ultrasonic irradiation. The resulting triple hydroxides were characterized by X-ray diffractometry, infrared and X-ray absorption spectroscopies, thermogravimetric analysis and scanning electron microscopy. The products were close-to-phase-pure CaAlFe-layered triple hydroxides. Elevation of the temperature transformed the CaAlFe-Cl(-)-layered triple hydroxide to rare oxyhalides (Ca2FeO3Cl and Ca12Al14O32Cl2).


Asunto(s)
Hidróxidos/química , Ultrasonido , Cloruros , Temperatura
14.
Ultrason Sonochem ; 31: 409-16, 2016 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-26964966

RESUMEN

CaAl-layered double hydroxides (CaAl-LDHs) were synthesised with various interlayer anions (CO3(2-), F(-), Cl(-), Br(-) and I(-)) by mechanochemical pre-treatment followed by ultrasonic irradiation in aqueous media. The parameters of the syntheses (duration of pre-milling and sonication, quality of the aqueous media, temperature) were altered in order to optimise the procedure and to understand the formation of LDH and other secondary products. The products were characterised by X-ray diffractometry (XRD) and scanning electron microscopy (SEM). The optimisation resulted in close-to-phase-pure CaAl-LDHs, not only with carbonate and chloride interlayer anions, but the hard-to-intercalate bromide and iodide as well.

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