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1.
J Clin Med ; 12(17)2023 Sep 02.
Artículo en Inglés | MEDLINE | ID: mdl-37685792

RESUMEN

Hypertension is an important morbidity factor. The prognostic consequences of the white-coat effect have been studied extensively. The repercussion on the circadian rhythm of urinary water and salt excretion in the same subgroup remain, conversely, among the open topics. Postulating an impaired diurnal sodium and volume excretion we decided to investigate both, in subjects with or without a white-coat effect, in the general population. A sample of 1023 subjects, has been considered. We collected 24-h urine samples, divided in day and night, and we measured the blood pressure with an Ambulatory Blood Pressure Monitoring (ABPM). ABPM values were then compared with physician collected in-office values to assign subjects to the group with or without the white-coat effect. Concerning the circadian pattern of urinary sodium excretion, we found no significant differences between the groups. There was instead in the white-coat effect group a higher night/day ratio of urinary water excretion. The white-coat effect, has been considered a potential hypertension precursor, and its consequent handling could be prospectively relevant in hypertension prevention. The absence of repercussions on the urinary circadian sodium excretion pattern and on the potentially related risk factors in subjects with a white coat effect is reassuring. The clinical significance of the impact on the night/day ratio of water excretion needs to be further investigated.

2.
United European Gastroenterol J ; 10(8): 836-843, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-35789124

RESUMEN

INTRODUCTION: Fecal calprotectin (FC) is established as a diagnostic marker to differentiate between inflammatory bowel diseases and non-inflammatory conditions. Furthermore, it may be effective in monitoring response to treatment, and to predict relapse during maintenance therapy. DESIGN: This was a prospective longitudinal study carried out in Italy, France and Spain. The primary objective was to correlate the LIAISON® Calprotectin assay measurements to quiescent ulcerative colitis (UC) or relapse as assessed by clinical data. Patients were assessed every 3 months for 12 months, and at 18 months. RESULTS: The last FC measured prior to relapse was the variable that predicted relapse in a statistically significant manner. With a 62.3 µg/g cut-off the area under the curve was 0.619, and the sensitivity was 62.9% (95% Confidence Interval [CI] 44.9%-78.5%) and specificity 63.0% (95% CI 53.1%-72.1%). Using machine learning methods, the last FC measurement was shown to have the largest impact in predicting relapse. An algorithm was developed that included other variables available following a clinician's visit, which resulted in an area under the curve of 0.754 for predicting relapse. CONCLUSION: In the present study FC measured by the LIAISON® Calprotectin assay on the visit before relapse is predictive of relapse in patients with quiescent UC. In a proof of concept, the accuracy of prediction can further be improved including other variables in an algorithm developed by machine learning. TRIAL REGISTRATION: The trial is registered at clinicaltrials.gov with reference number NCT05168917.


Asunto(s)
Colitis Ulcerosa , Complejo de Antígeno L1 de Leucocito , Biomarcadores , Colitis Ulcerosa/diagnóstico , Colitis Ulcerosa/tratamiento farmacológico , Heces , Humanos , Estudios Longitudinales , Estudios Prospectivos , Recurrencia
3.
Ecotoxicol Environ Saf ; 73(6): 1456-64, 2010 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-20674022

RESUMEN

The biological effects of a class of oxygenated imidazolium ionic liquids were studied in comparison with alkyl imidazolium salts (BMIM BF4 and BMIM N(CN)2).The cellular and subcellular effects were evaluated on rat pheochromocytoma PC12 cell lines, through MTT test, lactate dehydrogenase release and acetylcholinesterase inhibition; the eco-toxicological responses were assessed through the acute toxicity tests towards Daphnia magna and Vibrio fischeri. The introduction of ethoxy moieties in the lateral chain of imidazolium cations reduced the biological effects in all the tests. The acute toxicity towards D. magna was not affected by the number of ethoxy units, but the crustacean seemed to be sensitive to the type of anion; on the contrary, a further addition of ethoxy moieties increased the toxicity towards V. fischeri, M(OE)4MIM N(CN)2 being the most toxic oxygenated ionic liquid. In the cytotoxicity assays the salts with oxygenated cations resulted ineffective compared to BMIMs, independently from the anion and the number of ethoxy units in the lateral chain. In order to estimate the influence on membrane fluidity, an analysis of fluorescence anisotropy was done and it indicated that BMIM BF4, the most toxic ionic liquid among the tested ones, led to a destabilization of the model membranes at any molarity.


Asunto(s)
Aliivibrio fischeri/efectos de los fármacos , Daphnia/efectos de los fármacos , Contaminantes Ambientales/toxicidad , Imidazoles/toxicidad , Líquidos Iónicos/toxicidad , Acetilcolinesterasa/metabolismo , Animales , Supervivencia Celular/efectos de los fármacos , Contaminantes Ambientales/química , Imidazoles/química , Líquidos Iónicos/química , L-Lactato Deshidrogenasa/metabolismo , Oxidación-Reducción , Células PC12 , Ratas , Relación Estructura-Actividad , Pruebas de Toxicidad Aguda
5.
J Chromatogr A ; 1282: 142-52, 2013 Mar 22.
Artículo en Inglés | MEDLINE | ID: mdl-23411145

RESUMEN

EDDHSA/Fe is a promising substitute of EDDHA/Fe to fight iron chlorosis. o,o-EDDHSA structure contains two chiral carbons giving the racemic and meso couples of stereoisomers. Ion-pair HPLC and UHPLC-UV/Vis-ESI-MS/MS methods were developed for the determination of racemic and meso-o,o-EDDHSA/Fe in commercial samples of chelates. The lack of a commercial EDDHSA standard was overcome by sulfonation of a commercial available o,o-EDDHA standard and subsequent quantification by (1)H-NMR. Assignment of configurations was carried out starting from racemic and meso-o,o-EDDHA/Fe by direct sulfonation to give the corresponding o,o-EDDHSA/Fe isomers. The performances of these methods were assessed in terms of intra and inter-day precision, linearity and selectivity. The high selectivity and lower detection limit (nanomolar) of the UHPLC-ESI-MS/MS method could allow to deepen the knowledge relative to meso and rac-o,o-EDDHSA/Fe interactions with plants, its fate in different soil conditions, its mobility and other environmental aspects.


Asunto(s)
Cromatografía Líquida de Alta Presión/métodos , Hierro/análisis , Hierro/química , Fenilacetatos/análisis , Fenilacetatos/química , Espectrometría de Masas en Tándem/métodos , Acetonitrilos/química , Ácidos Acíclicos/química , Ácido Clorhídrico/química , Iones/análisis , Iones/química , Límite de Detección , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Espectrometría de Masa por Ionización de Electrospray , Estereoisomerismo
6.
ChemSusChem ; 2(11): 1045-50, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-19882702

RESUMEN

The chemoselective addition of tetraallyltin to dialkyl, alkenyl-alkyl, and alkynyl-alkyl ketones can be performed with high yields in N-methyl-N-butylpyrrolidinium trifuoromethansulfonate (MBP-Tf). Other room temperature ionic liquids (RTILs) can also be successfully employed if some sulfonic acid is added. The reaction is very sensitive to the electronic properties of the substrate. Aryl alkyl ketones bearing electron-withdrawing substituents behave like dialkyl ketones and react promptly; on the contrary, electron-rich aryl alkyl ketones react sluggishly, which allows selective competitive allylation of dialkyl substrates to occur. The ionic liquid solvent can be easily recycled, which meets the green chemistry principles of selectivity and reuse of chemicals. NMR spectroscopic data support the formation of tin-triflate catalysts in situ.


Asunto(s)
Compuestos Alílicos/química , Tecnología Química Verde/métodos , Líquidos Iónicos/química , Cetonas/química , Ácidos Sulfónicos/química , Aniones/química , Catálisis , Espectroscopía de Resonancia Magnética , Mesilatos/síntesis química , Mesilatos/química , Compuestos Organometálicos/química , Solventes/química , Temperatura , Estaño/química
7.
Environ Sci Technol ; 42(24): 9116-21, 2008 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-19174880

RESUMEN

Relevant concentrations of dimethyl- and diethylammonium salts (DMA+ and DEA+) were measured in submicrometer marine aerosol collected over the North Atlantic during periods of high biological activity (HBA) in clean air masses (median concentration (minimum-maximum)=26(6-56) ng m(-3)). Much lower concentrations were measured during periods of low biological activity (LBA): 1 (<0.4-20) ng m(-3) and when polluted air masses were advected to the sampling site: 2 (<0.2-24) ng m(-3). DMA+ and DEA+ are the most abundantorganic species, second only to MSA, detected in fine marine particles representing on average 11% of the secondary organic aerosol (SOA) fraction and a dominant part (35% on average) of the water-soluble organic nitrogen (WSON). Several observations support the hypothesis that DMA+ and DEA+ have a biogenic oceanic source and are produced through the reaction of gaseous amines with sulfuric acid or acidic sulfates. Moreover, the water-soluble fraction of nascent marine aerosol particles produced by bubble-bursting experiments carried out in parallel to ambient aerosol sampling over the open ocean showed WSON, DMA+, and DEA+ concentrations always below the detection limit, thus excluding an important primary sea spray source.


Asunto(s)
Aerosoles/análisis , Aminas Biogénicas/química , Compuestos Orgánicos/análisis , Agua de Mar/química , Eucariontes/química , Espectroscopía de Resonancia Magnética , Tamaño de la Partícula , Material Particulado/química , Compuestos de Amonio Cuaternario/química , Estaciones del Año , Agua/química
8.
Environ Sci Technol ; 41(7): 2479-84, 2007 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-17438803

RESUMEN

The functional group compositions of atmospheric aerosol water-soluble organic compoundswere obtained employing proton nuclear magnetic resonance (1H NMR) spectroscopy in a series of recent experiments in several areas of the world characterized by different aerosol sources and pollution levels. Here, we discuss the possibility of using 1H NMR functional group distributions to identifythe sources of aerosol in the different areas. Despite the limited variability of functional group compositions of atmospheric aerosol samples, characteristic 1H NMR fingerprints were derived for three major aerosol sources: biomass burning, secondary formation from anthropogenic and biogenic VOCs, and emission from the ocean. The functional group patterns obtained in areas characterized by one of the above dominant source processes were then compared to identify the dominant sources for samples coming from mixed sources. This analysis shows that H NMR spectroscopy can profitably be used as a valuable tool for aerosol source identification. In addition, compared to other existing methodologies, it is able to relate the source fingerprints to integral chemical properties of the organic mixtures, which determine their reactivity and their physicochemical properties and ultimately the fate of the organic particles in the atmosphere.


Asunto(s)
Aerosoles/química , Atmósfera/química , Técnicas de Química Analítica/métodos , Espectroscopía de Resonancia Magnética/métodos , Compuestos Orgánicos/análisis , Geografía
9.
Rev. Assoc. Paul. Cir. Dent ; 47(3): 1043-8, maio-jun. 1993. ilus
Artículo en Portugués | LILACS, BBO - odontología (Brasil) | ID: biblio-855522

RESUMEN

São expostos os resultados clínicos do uso do complexo colágeno-biocerâmica para reconstrução óssea. Dos 128 pacientes estudados, 71//obtiveram resultados classificados como ótimos. Os autores tecem considerações sobre detalhes da técnica e causas de insucesso


Asunto(s)
Humanos , Masculino , Femenino , Maxilares , Colágeno/uso terapéutico , Hidroxiapatitas/uso terapéutico , Cirugía Bucal , Cirugía Bucal/tendencias
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