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Marí-Alexandre J, Braza-Boils A, Molina P, Domingo D, Abellán Y, Sancho J, Hevia P, Ángel Arnau M, Gómez J, Giner J, Salvador A, Estellés A, Zorio E. C0423: MicroRNAs in Sudden Cardiac Death from Coronary Artery Disease. Its Relationship with Dyslipidemia and Non-Alcoholic Fatty Liver Disease. Thromb Res 2014. [DOI: 10.1016/s0049-3848(14)50068-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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Braza-Boils A, Marí-Alexandre J, Molina P, Domingo D, Sanz J, Sancho J, Abellán Y, Castillo N, Ángel Arnau M, Giner J, Montero A, Estellés A, Zorio E. C0420: MicroRNA Expression Profile in Epicardial Fat in Sudden Cardiac Death from Coronary Artery Disease. Thromb Res 2014. [DOI: 10.1016/s0049-3848(14)50067-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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García-Rodríguez S, Arias-Santiago S, Orgaz-Molina J, Magro-Checa C, Valenzuela I, Navarro P, Naranjo-Sintes R, Sancho J, Zubiaur M. Abnormal levels of expression of plasma microRNA-33 in patients with psoriasis. ACTAS DERMO-SIFILIOGRAFICAS 2014; 105:497-503. [PMID: 24656994 DOI: 10.1016/j.ad.2013.11.010] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2013] [Revised: 09/26/2013] [Accepted: 11/07/2013] [Indexed: 12/15/2022] Open
Abstract
INTRODUCTION AND OBJECTIVES Circulating microRNAs (miRNA) are involved in the posttranscriptional regulation of genes associated with lipid metabolism (miRNA-33) and vascular function and angiogenesis (miRNA-126). The objective of this exploratory study was to measure plasma levels of miRNA-33 and miRNA-126 in patients with plaque psoriasis and evaluate their association with clinical parameters. MATERIAL AND METHODS We studied 11 patients with plaque psoriasis. The median Psoriasis Area Severity Index (PASI) was 13 (interquartile range [IQR], 9-14) and body surface area involvement was 12 (IQR, 11-15). Eleven healthy controls matched for age and sex were also included. We analyzed cardiovascular risk factors and subclinical carotid atheromatosis. Plasma miRNAs were evaluated using quantitative real-time polymerase chain reaction. RESULTS Carotid intima-media thickness was greater in patients (0.57mm; IQR, 0.54-0.61; n=11) than in controls (0.50mm; IQR, 0.48-0.54; data available for 9 controls) (P=.0055, Mann-Whitney). Expression of miRNA-33 in patients (5.34; IQR, 3.12-7.96; n=11) was significantly higher than in controls (2.33; IQR, 1.71-2.84; only detected in 7 of 11 controls) (P=.0049, Wilcoxon signed rank). No differences in miRNA-126 levels were observed between patients and controls. In patients (n=11), we observed a positive correlation between miRNA-33 and insulin levels (r=0.7289, P=.0109) and a negative correlation between miRNA-126 and carotid intima-media thickness (r=-0.6181, P=.0426). CONCLUSION In psoriasis patients plasma levels of lipid and glucose metabolism-related miRNA-33 are increased and correlated with insulin. The study of circulating miRNA-33 in psoriasis may provide new insights about the associated systemic inflammatory abnormalities.
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García-Rodríguez S, Arias-Santiago S, Perandrés-López R, Orgaz-Molina J, Castellote L, Buendía-Eisman A, Ruiz J, Naranjo R, Navarro P, Sancho J, Zubiaur M. Decreased Plasma Levels of Clusterin in Patients With Psoriasis. ACTAS DERMO-SIFILIOGRAFICAS 2013. [DOI: 10.1016/j.adengl.2012.11.018] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
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Garcia-Rodriguez S, Arias-Santiago S, Perandrés-López R, Castellote L, Zumaquero E, Navarro P, Buendía-Eisman A, Ruiz JC, Orgaz-Molina J, Sancho J, M Zubiaur. Increased gene expression of Toll-like receptor 4 on peripheral blood mononuclear cells in patients with psoriasis. J Eur Acad Dermatol Venereol 2013; 27:242-50. [PMID: 23457721 DOI: 10.1111/j.1468-3083.2011.04372.x] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
BACKGROUND A role for the innate immune system in driving the autoimmune T cell cascade in psoriasis has been proposed. Toll-like receptors-(TLR)-2 and -4 play a role in inflammation, atherosclerosis, and their specific role in psoriasis remains unclear. OBJECTIVE To evaluate TLR2 and TLR4 gene expression levels in peripheral blood mononuclear cells from psoriatic patients. METHODS Changes in TLR2 ⁄ 4 gene expressions were evaluated using quantitative real-time reverse transcription polymerase chain reaction in peripheral blood mononuclear cells, from twenty-one patients with severe psoriasis, and analysed whether there was any correlation with cytokine plasma levels (T-helper 0-, T-helper 1-, T-helper 2- or regulatory T cells-type), or Calprotectin and with S100A8 and S100A9 gene expression levels. Eleven non-psoriatic healthy controls were analysed. RESULTS A clear increase in TLR4 gene expression was observed (3.84 ± 0.93, n = 21) together with a moderate increase in TLR2 expression (1.522 ± 0.31, n = 21). Both TLR4 and TLR2 gene expressions were significantly augmented in psoriatic patients compared with controls (all P < 0.001). Correlations between TLR2 and S100A9 gene expressions (r = 0.5145, P = 0.0170, n = 21); and between TLR2 expression and plasma interleukin-2 (r = 0.5667, P = 0.0074); interleukin-4 (r = 0.4766, P = 0.0289), interleukin-10 (r = 0.4355, P = 0.0484) and interleukin-13 (r = 0.4603, P = 0.0358), were found. When patients with atheroma plaque were considered (n = 7), both TLR4 (3.47 ± 0.99, P = 0.0156) and TLR2 (1.63 ± 0.31, P = 0.0156) expressions were significantly increased vs. controls and correlated with plasma TNF-a (r = 0.8929, P = 0.0123, in both cases). CONCLUSION Differential TLR4 ⁄ 2 gene expressions on psoriatic peripheral blood mononuclear cells and correlations with regulatory and ⁄ or proinflammatory cytokines and ⁄ or damage-associated molecular pattern molecule S100A9 emphasize innate immune response role in psoriasis.
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García-Rodríguez S, Arias-Santiago S, Perandrés-López R, Orgaz-Molina J, Castellote L, Buendía-Eisman A, Ruiz JC, Naranjo R, Navarro P, Sancho J, Zubiaur M. Decreased plasma levels of clusterin in patients with psoriasis. ACTAS DERMO-SIFILIOGRAFICAS 2013; 104:497-503. [PMID: 23522962 DOI: 10.1016/j.ad.2012.11.019] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2012] [Revised: 11/22/2012] [Accepted: 11/27/2012] [Indexed: 12/11/2022] Open
Abstract
INTRODUCTION AND OBJECTIVES Psoriasis is a chronic inflammatory disease that has been linked to increased cardiovascular risk. The glycoprotein clusterin (apolipoprotein J) is a component of high-density lipoproteins and has a protective role in atherosclerosis. The aim of the present study was to evaluate the plasma levels of clusterin and the proinflammatory cytokine macrophage migration inhibitory factor (MIF) in patients with severe psoriasis, comparing groups of patients with different risks of cardiovascular disease. MATERIAL AND METHODS Twenty-one patients with severe psoriasis (psoriasis area severity index and body surface area>10) and 11 healthy controls with no dermatologic disease were studied. Cardiovascular risk factors were assessed according to the Adult Treatment Panel (ATP) III criteria. Subclinical carotid atheromatosis was assessed by Doppler ultrasonography of the carotid arteries. Plasma clusterin and MIF levels were measured by enzyme-linked immunosorbent assay. RESULTS ATP-III criteria for metabolic syndrome were met by 47% of the patients, and 33% had carotid atheromatous plaque. Mean (SD) clusterin plasma levels were significantly lower in patients with psoriasis compared with controls (81.39 [27.30] μg/mL for the 21 patients vs 117 [21.6] μg/mL for the 11 controls; P=.0017). MIF plasma levels (ng/ml) were significantly higher in patients with atheromatous plaque compared with controls (53.22 [29.02] for the 6 patients with plaque vs 34.21 [9.65] for the 11 controls; P=.0394). CONCLUSIONS The decreased plasma levels of clusterin in psoriatic patients suggested an association with the disease and might be an indicator of systemic inflammatory activity. Increased levels of MIF appear to be associated with cardiovascular risk factors and carotid atheromatous plaque.
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Diaz R, Ibáñez M, Sancho J, Hernández F. Qualitative validation of a liquid chromatography–quadrupole-time of flight mass spectrometry screening method for organic pollutants in waters. J Chromatogr A 2013; 1276:47-57. [DOI: 10.1016/j.chroma.2012.12.030] [Citation(s) in RCA: 60] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2012] [Revised: 12/12/2012] [Accepted: 12/13/2012] [Indexed: 10/27/2022]
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Masiá A, Ibáñez M, Blasco C, Sancho J, Picó Y, Hernández F. Combined use of liquid chromatography triple quadrupole mass spectrometry and liquid chromatography quadrupole time-of-flight mass spectrometry in systematic screening of pesticides and other contaminants in water samples. Anal Chim Acta 2013; 761:117-27. [DOI: 10.1016/j.aca.2012.11.032] [Citation(s) in RCA: 106] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2012] [Revised: 10/16/2012] [Accepted: 11/18/2012] [Indexed: 10/27/2022]
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Antman Y, Primerov N, Sancho J, Thevenaz L, Zadok A. Localized and stationary dynamic gratings via stimulated Brillouin scattering with phase modulated pumps. OPTICS EXPRESS 2012; 20:7807-7821. [PMID: 22453458 DOI: 10.1364/oe.20.007807] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
A novel technique for the localization of stimulated Brillouin scattering (SBS) interaction is proposed, analyzed and demonstrated experimentally. The method relies on the phase modulation of two counter-propagating optical waves by a common pseudo-random bit sequence (PRBS), these waves being spectrally detuned by the Brillouin frequency shift. The PRBS symbol duration is much shorter than the acoustic lifetime. The interference between the two modulated waves gives rise to an acoustic grating that is confined to narrow correlation peaks, as short as 1.7 cm. The separation between neighboring peaks, which is governed by the PRBS length, can be made arbitrarily long. The method is demonstrated in the generation and applications of dynamic gratings in polarization maintaining (PM) fibers. Localized and stationary acoustic gratings are induced by two phase modulated pumps that are polarized along one principal axis of the PM fiber, and interrogated by a third, readout wave which is polarized along the orthogonal axis. Using the proposed technique, we demonstrate the variable delay of 1 ns-long readout pulses by as much as 770 ns. Noise due to reflections from residual off-peak gratings and its implications on the potential variable delay of optical communication data are discussed. The method is equally applicable to the modulation of pump and probe waves in SBS over standard fibers.
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Sancho J, Primerov N, Chin S, Antman Y, Zadok A, Sales S, Thévenaz L. Tunable and reconfigurable multi-tap microwave photonic filter based on dynamic Brillouin gratings in fibers. OPTICS EXPRESS 2012; 20:6157-62. [PMID: 22418495 DOI: 10.1364/oe.20.006157] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/14/2023]
Abstract
We propose and experimentally demonstrate new architectures to realize multi-tap microwave photonic filters, based on the generation of a single or multiple dynamic Brillouin gratings in polarization maintaining fibers. The spectral range and selectivity of the proposed periodic filters is extensively tunable, simply by reconfiguring the positions and the number of dynamic gratings along the fiber respectively. In this paper, we present a complete analysis of three different configurations comprising a microwave photonic filter implementation: a simple notch-type Mach-Zehnder approach with a single movable dynamic grating, a multi-tap performance based on multiple dynamic gratings and finally a stationary grating configuration based on the phase modulation of two counter-propagating optical waves by a common pseudo-random bit sequence (PRBS).
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Ayuso-Tejedor S, Abián O, Velázquez-Campoy A, Sancho J. Mechanism of FMN Binding to the Apoflavodoxin from Helicobacter pylori. Biochemistry 2011; 50:8703-11. [PMID: 21910456 DOI: 10.1021/bi201025y] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Flavodoxins are bacterial electron transport proteins whose redox competence is due to the presence of a tightly but noncovalently bound FMN molecule. While the thermodynamics of the complex are understood, the mechanism of association between the apoflavodoxin and the redox cofactor is not so clear. We investigate here the mechanism of FMN binding to the apoflavodoxin from Helicobacter pylori, an essential protein that is being used as a target to develop antimicrobials. This flavodoxin is structurally peculiar as it lacks the typical bulky residue interacting with the FMN re face but bears instead a small alanine. FMN binding is biphasic, regardless of the presence of phosphate molecules in solution, while riboflavin binding takes place in a single step, the rate constant of which coincides with the fast phase of FMN binding. A mutational study at the isoalloxazine and phosphate subsites for FMN binding clearly indicates that FMN association is always limited by interaction with the isoalloxazine subsite because mutating residues that interact with the phosphate moiety of FMN in the native complex hardly changes the observed rate constants and amplitudes. In contrast, replacing tyr92, which interacts with the isoalloxazine, greatly lowers the rate constants. Our analysis indicates that the two FMN binding phases observed are related neither with alternative or sequential interaction with the two binding subsites nor with the presence of bound phosphate. It is possible that they reflect the intrinsic conformational heterogeneity of the apoflavodoxin ensemble.
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Martínez-Serrano MA, Pereira JA, Sancho J, Argudo N, López-Cano M, Grande L. Specific improvement measures to reduce complications and mortality after urgent surgery in complicated abdominal wall hernia. Hernia 2011; 16:171-7. [PMID: 21909976 DOI: 10.1007/s10029-011-0875-0] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2010] [Accepted: 08/04/2011] [Indexed: 10/17/2022]
Abstract
PURPOSE Morbidity and mortality are increased after urgent surgery for complicated abdominal wall hernia. We analysed prospectively early morbidity and mortality after implementing specific management measures in patients undergoing urgent hernia repair. METHODS The study population included 244 patients with complicated abdominal wall hernia requiring surgical repair on an emergency basis over 1-year period. Patients were managed according to a protocol that included specific actions to be implemented in the pre-, intra- and postoperative periods. Outcomes of these patients were compared with those of 402 undergoing similar operations before development of the protocol. RESULTS Patients in whom acute complication was the first hernia symptom had higher mortality (7.2% vs 2.5%; P = 0.07) and were consulted later than 24 h (49.4% vs 36%; P = 0.044). Patients consulting later than 24 h had higher mortality (8.1% vs 1.4%, P = 0.017). Femoral hernias exhibited specific characteristics and were associated with higher mortality (13% vs 1.6%; P = 0.001). Overall, both groups had similar mortality (4.5% vs 4.1%; P = 0.8); complications (38.8% vs 37.7%; P = 0.2), and bowel resection rates (12.2% vs 11.5%; P = 0.8). Excluding the group of femoral hernias, the measures achieved a lower rate of severe complications (21.2% vs 10.3%; P = 0.04) and a decrease in mortality (2.9% vs 0.6%; P = 0.05) after bowel resection. CONCLUSIONS Specific measures for improvement of management and prevention of complications and mortality were effective in patients without femoral hernia. To reduce mortality, the best applicable measure is early detection and to prioritize the scheduled operation of femoral hernias and those affecting high risk patients. The implementation of preventive and educational programs in high risk patients is essential.
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Ruiz M, Garcia O, Hernán I, Sancho J, Serracanta J, Barret JP. Revolving-door flap: an alternative for the coverage of acute burn defects of the auricle. Burns 2011; 37:e41-3. [PMID: 21723043 DOI: 10.1016/j.burns.2011.02.001] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2010] [Accepted: 02/05/2011] [Indexed: 10/18/2022]
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Arias-Moreno X, Abian O, Vega S, Sancho J, Velazquez-Campoy A. Protein-Cation Interactions: Structural and Thermodynamic Aspects. Curr Protein Pept Sci 2011; 12:325-38. [DOI: 10.2174/138920311795906664] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2010] [Accepted: 03/14/2011] [Indexed: 11/22/2022]
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Arias-Moreno X, Abian O, Vega S, Sancho J, Velazquez-Campoy A. Protein-Cation Interactions: Structural and Thermodynamic Aspects. Curr Protein Pept Sci 2011. [DOI: 10.2174/1389211214015232037] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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De la Torre JE, Moya ER, Bota E, Sancho J. Estudio físico-químico y microbiológico de la fermentación de aceitunas verdes arbequinas. GRASAS Y ACEITES 2010. [DOI: 10.3989/gya.1993.v44.i4-5.1079] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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Arnó A, García O, Hernán I, Sancho J, Acosta A, Barret J. Extracorporeal shock waves, a new non-surgical method to treat severe burns. Burns 2010; 36:844-9. [DOI: 10.1016/j.burns.2009.11.012] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2009] [Revised: 09/21/2009] [Accepted: 11/10/2009] [Indexed: 11/26/2022]
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Hernández F, Sancho J, Ibáñez M, Grimalt S. Investigation of pesticide metabolites in food and water by LC-TOF-MS. Trends Analyt Chem 2008. [DOI: 10.1016/j.trac.2008.08.011] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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Parra J, Sancho J, Miranda-Gonzalbo V, Brocalero-Camacho A. [Injury to both internal globus pallidi due to hypoxic encephalopathy as a consequence of respiratory arrest following the consumption of opiates and benzodiazepines]. Rev Neurol 2007; 44:243-4. [PMID: 17311215] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/14/2023]
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Cuesta-López S, Falo F, Sancho J. Computational diagnosis of protein conformational diseases: Short molecular dynamics simulations reveal a fast unfolding of r-LDL mutants that cause familial hypercholesterolemia. Proteins 2006; 66:87-95. [PMID: 17044057 DOI: 10.1002/prot.21181] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
The molecular basis of conformational diseases frequently resides in mutant proteins constituting a subset of the vast mutational space. While the subtleties of protein structure point to molecular dynamics (MD) techniques as promising tools for an efficient exploration of such a space, the average size of proteins and the time scale of unfolding events make this goal difficult with present computational capabilities. We show here, nevertheless, that an efficient approach is already feasible for modular proteins. Familial hypercholesterolemia (FH) is a conformational disease linked to mutations in the gene encoding the low density lipoprotein receptor. A high percentage of these mutations has been found in the seven small modular binding repeats of the receptor. Taking advantage of its small size, we have performed an in depth MD study of the fifth binding repeat. Fast unfolding dynamics have been observed in the absence of a structural bound calcium ion, which agrees with its reported essential role in the stability of the module. In addition, several mutations detected in FH patients have been analyzed, starting from the native conformation. Our results indicate that in contrast with the wild type protein and an innocuous control mutant, disease-related mutants experience, in short simulation times (2-8 ns), gross departures from the native state that lead to unfolded conformations and, in some cases, to binding site desorganization deriving in calcium release. Computational diagnosis of mutations leading to conformational diseases seems thus feasible, at least for small or modular pathogenic proteins.
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López-Llano J, Campos LA, Sancho J. Alpha-helix stabilization by alanine relative to glycine: roles of polar and apolar solvent exposures and of backbone entropy. Proteins 2006; 64:769-78. [PMID: 16755589 DOI: 10.1002/prot.21041] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
The energetics of alpha-helix formation are fairly well understood and the helix content of a given amino acid sequence can be calculated with reasonable accuracy from helix-coil transition theories that assign to the different residues specific effects on helix stability. In internal helical positions, alanine is regarded as the most stabilizing residue, whereas glycine, after proline, is the more destabilizing. The difference in stabilization afforded by alanine and glycine has been explained by invoking various physical reasons, including the hydrophobic effect and the entropy of folding. Herein, the contribution of these two effects and that of hydrophilic area burial is evaluated by analyzing Ala and Gly mutants implemented in three helices of apoflavodoxin. These data, combined with available data for similar mutations in other proteins (22 Ala/Gly mutations in alpha-helices have been considered), allow estimation of the difference in backbone entropy between alanine and glycine and evaluation of its contribution and that of apolar and polar area burial to the helical stabilization typically associated to Gly-->Ala substitutions. Alanine consistently stabilizes the helical conformation relative to glycine because it buries more apolar area upon folding and because its backbone entropy is lower. However, the relative contribution of polar area burial (which is shown to be destabilizing) and of backbone entropy critically depends on the approximation used to model the structure of the denatured state. In this respect, the excised-peptide model of the unfolded state, proposed by Creamer and coworkers (1995), predicts a major contribution of polar area burial, which is in good agreement with recent quantitations of the relative enthalpic contribution of Ala and Gly residues to alpha-helix formation.
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Pons Amate J, Sancho J, Romero Martínez A, Juni J, Cervelló Donderis A. [Evolution of severe pain associated to spontaneous spinal epidural hematoma]. Neurologia 2006; 21:405-10. [PMID: 17013784] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/12/2023] Open
Abstract
INTRODUCTION Spontaneous spinal epidural hematoma is an infrequent disease, whose clinical presentation is very characteristic, with severe pain in region corresponding to the metameres affected, which orients its diagnosis and early treatment. CLINICAL CASES Three clinical cases that occurred during 2003 and 2004 are presented. All three were middle- aged men, with spondyloarthrosis signs, posterolateral cervical location of hematoma, which debuted with severe cervical and cervicobrachial pain. This was followed by acute onset motor and sensory paralysis with spontaneous complete recovery in hours, only the pain persisting. The three patients were treated conservatively, pain being the main symptom. This pain only responded to intravenous steroids. CONCLUSIONS The evolution of the pain and pathophysiological mechanism by which the corticoids could improve the pain associated to these diseases are discussed.
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Masia J, Leon X, Sancho J, Quer M, Arno A, Vega C. O.153 Head and neck soft tissue reconstruction with perforator flaps. J Craniomaxillofac Surg 2006. [DOI: 10.1016/s1010-5182(06)60182-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
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Campos LA, Sancho J. Native-specific stabilization of flavodoxin by the FMN cofactor: structural and thermodynamical explanation. Proteins 2006; 63:581-94. [PMID: 16444751 DOI: 10.1002/prot.20855] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
Flavodoxins are useful models to investigate protein/cofactor interactions. The binding energy of the apoflavodoxin-FMN complex is high and therefore the holoflavodoxin is expected to be more stable than the apoprotein. This expectation has been challenged by reports on the stability of Desulfovibrio desulfuricans flavodoxin indicating that FMN binds to the unfolded polypeptide with similar affinity as to the native state, thus causing no net effect on protein stability. In previous work, we have analyzed in detail the stability of the apoflavodoxin from Anabaena PCC 7119 and the energetics of its functional complex with FMN. Here, we use the Anabaena holoprotein to directly investigate the contribution of the bound cofactor to protein stability through a detailed analysis of the chemical and thermal denaturation equilibria. Our data clearly shows that FMN binding largely stabilizes the protein towards both chemical and thermal denaturation, and that the stabilization observed at 25 degrees C in low ionic strength conditions is precisely the one expected if full release of the cofactor takes place upon flavodoxin unfolding. On the other hand, the binding of FMN to the native polypeptide is shown to simplify the thermal unfolding so that, while apoflavodoxin follows a three-state mechanism, the holoprotein unfolds in a two-state fashion. Comparison of the X-ray structure of native apoflavodoxin with the phi-structure of the thermal intermediate indicates that the increase in cooperativity driven by the cofactor originates in its preferential binding to the native state, which is a consequence of the disorganization in the intermediate of the FMN binding loops and of an adjacent longer loop.
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Pons G, Masia J, Sancho J, Larrañaga J, Serret P. Head and Neck Reconstruction with Perforator Flaps. J Reconstr Microsurg 2006. [DOI: 10.1055/s-2006-947966] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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