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1.
J Endocrinol Invest ; 46(10): 2133-2146, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-36971952

RESUMEN

PURPOSE: Potential negative effects of metabolic surgery on skeletal integrity remain a concern, since long-term data of different surgical approaches are poor. This study aimed to describe changes in bone metabolism in subjects with obesity undergoing both Roux-en-Y gastric bypass (RYGB) and sleeve gastrectomy (SG). METHODS: A single center, retrospective, observational clinical study on real-world data was performed enrolling subjects undergoing metabolic surgery. RESULTS: 123 subjects were enrolled (males 31: females 92; ages 48.2 ± 7.9 years). All patients were evaluated until 16.9 ± 8.1 months after surgery, while a small group was evaluated up to 4.5 years. All patients were treated after surgery with calcium and vitamin D integration. Both calcium and phosphate serum levels significantly increased after metabolic surgery and remained stable during follow-up. These trends did not differ between RYGB and SG (p = 0.245). Ca/P ratio decreased after surgery compared to baseline (p < 0.001) and this decrease remained among follow-up visits. While 24-h urinary calcium remained stable across all visits, 24-h urinary phosphate showed lower levels after surgery (p = 0.014), also according to surgery technique. Parathyroid hormone decreased (p < 0.001) and both vitamin D (p < 0.001) and C-terminal telopeptide of type I collagen (p = 0.001) increased after surgery. CONCLUSION: We demonstrated that calcium and phosphorous metabolism shows slight modification even after several years since metabolic surgery, irrespective of calcium and vitamin D supplementation. This different set point is characterized by a phosphate serum levels increase, together with a persistent bone loss, suggesting that supplementation alone may not ensure the maintenance of bone health in these patients.


Asunto(s)
Cirugía Bariátrica , Densidad Ósea , Masculino , Femenino , Humanos , Estudios Retrospectivos , Calcio , Obesidad/complicaciones , Obesidad/cirugía , Vitamina D , Fosfatos
2.
Anal Bioanal Chem ; 402(4): 1551-7, 2012 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-21805064

RESUMEN

Unilateral and solid-state nuclear magnetic resonance (NMR) analyses were performed on a parchment fragment of the Dead Sea Scroll (DSS). The analyzed sample belongs to the collection of non-inscribed and nontreated fragments of known archaeological provenance from the John Rylands University Library in Manchester. Therefore, it can be considered as original DSS material free from any contamination related to the post-discovery period. Considering the paramount significance of the DSS, noninvasive approaches and portable in situ nondestructive methods are of fundamental importance for the determination of composition, structure, and chemical-physical properties of the materials under study. NMR studies reveal low amounts of water content associated with very short proton relaxation times, T(1), indicating a high level of deterioration of collagen molecules within scroll fragments. In addition, (13)C cross-polarization magic-angle-spinning (CPMAS) NMR spectroscopy shows characteristic peaks of lipids whose presence we attribute to the production technology that did not involve liming. Extraction with chloroform led to the reduction of both lipid and protein signals in the (13)C CPMAS spectrum indicating probable involvement of lipids in parchment degradation processes. NMR absorption and relaxation measurements provide nondestructive, discriminative, and sensitive tools for studying the deterioration effects on the organization and properties of water and collagen within ancient manuscripts.


Asunto(s)
Arqueología/métodos , Colágeno/química , Espectroscopía de Resonancia Magnética/métodos , Manuscritos como Asunto/historia , Arqueología/historia , Cristianismo/historia , Historia Antigua , Israel , Judaísmo/historia , Agua/química
3.
J Steroid Biochem Mol Biol ; 127(1-2): 139-46, 2011 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-21397020

RESUMEN

Food is likely to be one of the most important routes of human exposure to endocrine disrupting compounds (EDCs). In the present study, we evaluated the total estrogenic activity of fruits and vegetables, which was calculated using the human breast cancer cell line (MCF-7 BUS) proliferation assay (E-screen), in relation to pesticide residues. We analysed 44 food samples, 30 fruits and 14 vegetables. Of these samples, 10 did not contain any pesticide residues. The other 34 samples contained from 1 to 7 pesticide residues in concentrations ranging from 0.03 to 1.91 ppm. Estrogenic activity was detected in the 59% of samples tested. The positive controls used were 17-ß-estradiol (E2), the phytoestrogen genistein and the pesticide endosulfan. The average value of estradiol equivalency quantity (EEQ) for all positive samples was 0.15±0.32 µg/100g. A low correlation was found between the concentration of pesticide residues and the EEQ values (Spearman correlation r=0.376 and p=0.012). Using values obtained from the literature, we compared the estrogenic activity of food samples with the intrinsic content of phytoestrogens, but we found no correlations. Our results also suggested that the calculated intake of dietary EDCs might represent a concentration comparable to the normal endogenous estrogen concentration in human blood.


Asunto(s)
Bioensayo/métodos , Disruptores Endocrinos/análisis , Frutas/química , Residuos de Plaguicidas/análisis , Verduras/química , Línea Celular Tumoral , Femenino , Humanos
4.
Langmuir ; 24(6): 2808-19, 2008 Mar 18.
Artículo en Inglés | MEDLINE | ID: mdl-18251562

RESUMEN

Acid clays were prepared by exchanging a synthetic saponite in HCl solutions of different concentration (0.01 and 1M, respectively). A combined experimental approach (XRD, HRTEM, N2 physisorption, solid-state MAS NMR, and TGA) was used to investigate on the structural, morphological, and textural features of the samples treated under mild and strong acid conditions. FTIR spectroscopy of adsorbed probe molecules with different basicity (e.g., CO and NH3) was used to monitor the surface acid properties and acid site distribution. XRD and SS-MAS NMR indicated that the activation under mild acid conditions does not alter the clay structure, while a deep modification of the saponite framework occurred after ion exchange in 1 M HCl solution. The presence of porous amorphous silica phase after treatment under strong acid conditions was confirmed by TEM inspection augmented by SS-MAS NMR and FTIR spectroscopy. N2 and Ar physisorption measurements suggested that cavitation phenomena occurred in saponite structure. N2 physisorption confirmed that the porosity and surface area of the samples are strongly modified upon strong acid treatment. FTIR spectroscopy of adsorbed NH3 pointed out that the H-exchange in mild conditions increased the number of surface Brønsted acid sites. Conversely, these sites are significantly depleted after treatment under strong acid conditions. The use of CO as a FTIR probe molecule, which is applied for the first time to study synthetic acid clays, allowed to monitor distribution and strength of Brønsted acid sites, whose acidity is similar to that of strong acid zeolites. The Al-OH sites with medium acidity are also found in acid-activated saponites. The distribution of strong and medium acid sites is strictly dependent on the acid conditions adopted.

5.
Chem Res Toxicol ; 13(10): 971-5, 2000 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-11080045

RESUMEN

The selective interaction of ascorbic acid with crystalline silica (quartz) has been studied by measuring the ascorbic acid consumption (by means of UV/vis and IR spectroscopy) and the release of silicon when quartz particles or amorphous silica (Aerosil 50) is incubated in ascorbic acid solution. At a physiological ascorbic acid concentration, quartz, and not amorphous silica, reacts, suggesting the formation of a 1:1 silicon-ascorbate complex, while at higher concentrations, the reacting amount of ascorbic acid exceeds the amount of silicon that is released. Silicon tetrahedra bearing free silanols at the quartz surface are selectively attached by ascorbic acid. The particle-derived hydroxyl radical yield in the presence of hydrogen peroxide is increased on ascorbic acid-treated quartz in comparison with the original sample. The results presented herein are relevant because the depletion of ascorbic acid from the lung lining layer and the increased potential in particle-derived free radical generation may both contribute to the oxidative damage following inhalation of crystalline silica.


Asunto(s)
Ácido Ascórbico/química , Cuarzo/química , Dióxido de Silicio/química , Polvo/efectos adversos , Radicales Libres/química , Exposición por Inhalación/efectos adversos , Oxidación-Reducción , Solubilidad , Espectrofotometría Infrarroja , Espectrofotometría Ultravioleta
7.
G Batteriol Virol Immunol ; 68(7-12): 208-23, 1975.
Artículo en Italiano | MEDLINE | ID: mdl-1234590

RESUMEN

The results obtained by antibodies titration in 1500 subjects, in connection with Toxoplasma infection, are discussed. The determinant influence of some factors is statistically evaluated and recent Italian and foreign results are considered, according to the epidemiology of Toxoplasmosis.


Asunto(s)
Toxoplasmosis/epidemiología , Adolescente , Adulto , Factores de Edad , Anciano , Anticuerpos/análisis , Niño , Femenino , Humanos , Italia , Masculino , Persona de Mediana Edad , Ocupaciones , Población Rural , Factores Sexuales
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