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Goyache F, Gutiérrez J, Fernández I, Royo L, Álvarez I. Genetic analysis of days open in beef cattle. ACTA ACUST UNITED AC 2005. [DOI: 10.1016/j.livprodsci.2004.10.002] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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227
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Hidalgo C, Díez C, Duque P, Prendes JM, Rodríguez A, Goyache F, Fernández I, Facal N, Ikeda S, Alonso-Montes C, Gómez E. Oocytes recovered from cows treated with retinol become unviable as blastocysts produced in vitro. Reproduction 2005; 129:411-21. [PMID: 15798016 DOI: 10.1530/rep.1.00548] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Retinoids have been shown to enhance developmental competence of the oocyte in cattle, sheep and pigs. In this study we investigated whether exogenous retinol stimulates the bovine oocyte during its intrafollicular growth and the time limits of exposure to exogenous retinol. In addition, we also determined the efficiency of ovum pick-up techniques in combination with retinol treatment and the viability of embryos after transfer to recipients. In Experiment 1, heifers were injected with retinol or vehicle, and concentrations of retinol in the blood were analysed on Day 0 (prior to injection), Day 1 and, together with follicular fluid, Day 4. Blood retinol increased by Day 1 and cleared on Day 4, but retinol remained higher within the follicle. In Experiment 2, oocyte donors were injected weekly with retinol or vehicle four times during a twice-per-week cycle of eight recovery sessions (starting 4 days before the first session), followed by a second eight-session cycle without treatment. Oocytes recovered were fertilized and culturedin vitro.Retinol treatment yielded higher numbers of low-quality oocytes throughout, although retinol measured during cycles did not change. Total oocytes, and morulae and blastocyst rates, increased during the first five sessions following treatment with retinol. As previously shown with oocytes from slaughterhouse ovaries, retinoic acid stimulated blastocyst development. Following transfer to recipients, blastocysts from oocytes exposed to retinol were unable to establish pregnancy. Our study confirms the existence of an effect of retinol on the intrafollicular oocyte in the cow and provides evidence regarding the teratogenic effect of retinol.
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Alvarez I, Gutiérrez JP, Royo LJ, Fernández I, Gómez E, Arranz JJ, Goyache F. Testing the usefulness of the molecular coancestry information to assess genetic relationships in livestock using a set of Spanish sheep breeds1. J Anim Sci 2005; 83:737-44. [PMID: 15753326 DOI: 10.2527/2005.834737x] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Recent studies have proposed the use of molecular coancestry coefficients as a measure of genetic variability and as a useful tool for conservation purposes. Using simulated data, molecular coancestry has been shown to become constant very quickly after separation of populations, leading to population diversity remaining constant. However, the use of molecular coancestry information to study the genetic relationships between breeds has not yet been widely explored. Here we analyze the polymorphism of 14 microsatellites in 222 unrelated individuals belonging to seven native Spanish breeds to ascertain the usefulness of molecular coancestry-based methodologies in providing information on their genetic relationships. Average kinship distance (D(k)) and average molecular coancestry coefficients (f(ij)) were compared with well-known genetic distances, such as between-breed Reynolds' distance (D(R)), Nei's standard distance (D(s)), and shared allele distance (D(AS)). Kinship distance and f(ij) have moderate to low correlations with the other genetic distances, showing that they provide different information: both D(k) and f(ij) account for the allele frequencies in the founder population, whereas D(R), D(s), and D(AS) characterize the short-term evolution of the populations. Furthermore, D(k) and f(ij) were only moderately correlated (-0.500). The present study used field data to confirm previous research pointing out the ability of molecular coancestry coefficients to assess genetic differentiation of an ancestral origin. In this respect, molecular coancestry-based parameters may be used with classical genetic parameters to obtain information on population dynamics in livestock breeds. This study additionally presents reliable evidence on the history of these sheep breeds.
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Alvarez I, Royo LJ, Fernández I, Gutiérrez JP, Gómez E, Goyache F. Genetic relationships and admixture among sheep breeds from Northern Spain assessed using microsatellites. J Anim Sci 2005; 82:2246-52. [PMID: 15318720 DOI: 10.2527/2004.8282246x] [Citation(s) in RCA: 62] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Although many research papers have studied diversity and differentiation within livestock species, genetic relationships among neighboring populations remain poorly understood. Here we apply recent methodologies to analyze the polymorphism of 14 microsatellites in 238 unrelated individuals belonging to six sheep breeds from Northern Spain to ascertain their historical relationships and the relative genetic contributions existing between populations. Individual genotypes were analyzed to assess the existence of an underlying genetic structure. Long-term and recent migration rates were estimated to identify patterns of relative genetic contribution among breeds. The complete data set showed a strong population structure derived from both different ancestral origins and some geographical patterns of recent gene flow. Two of the analyzed breeds (Black-faced Latxa and Churra) had a marked genetic background, supporting the hypothesis that, regardless of their phenotypical similarities, they have different ancestral origins. Some of the more presumably related breeds had negative long-term admixture coefficients, showing that they diverged only recently. In addition, we show how methodologies for estimation of long-term gene flow and recent patterns of migration are complementary, providing information about migration rates on different timescales.
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Cuadrado I, Ramos JL, Fernández I. Análisis del discurso con desempleados de larga duración durante entrevistas de inserción laboral. INTERNATIONAL JOURNAL OF SOCIAL PSYCHOLOGY 2005. [DOI: 10.1174/0213474053683149] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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231
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Zarrabeitia MT, Alonso A, Zarrabeitia A, Castro A, Fernández I, de Pancorbo MM. X-linked microsatellites in two Northern Spain populations. Forensic Sci Int 2004; 145:57-9. [PMID: 15374595 DOI: 10.1016/j.forsciint.2004.02.025] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2003] [Revised: 02/18/2004] [Accepted: 02/22/2004] [Indexed: 11/19/2022]
Abstract
The X-chromosomal microsatellites HPRTB, DXS101, ARA, DXS7423, and DXS8377 were analysed by a pentaplex PCR in an expanded population sample from Cantabria and an independent sample of unrelated individuals from the Basque Country. Allele frequencies showed similar distributions, but minor variations were found for some loci.
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García Ruano JL, Alemán J, del Prado M, Fernández I. Stereoselective Addition of α-Sulfinyl Carbanions toN-p-tolylsulfinylketimines: Synthesis of Optically Pure 1,2,2‘-Trialkyl-2-aminoethanols. J Org Chem 2004; 69:4454-63. [PMID: 15202901 DOI: 10.1021/jo049666s] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The reactions of lithium carbanions derived from both enantiomers of methyl (1) and ethyl p-tolyl sulfoxide (2) with (S)-N-arylsulfinylketimines 3 and 4 took place in a highly stereoselective manner and good isolated yields. The configuration of the carbon bonded to nitrogen relies exclusively on the N-sulfinylimine configuration. When ethyl p-tolyl sulfoxide (2) is use as nucleophile, two chiral centers are created simultaneously, where the configuration of the carbon bonded to the sulfur is mainly controlled by 2. The asymmetric induction increases with the temperature, being total at room temperature in the case of the matched pair of reactants. A non-oxidative Pummerer reaction on the obtained aminosulfoxides allows a straightforward synthesis of optically pure 1,2-ethanolamines with one or two chiral centers, including amino alcohols with a bulky quaternary carbon bonded to the amine group.
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Fernández I, Loinaz C. Antiviral therapy of recurrent hepatitis C in liver transplantation. REVISTA ESPANOLA DE ENFERMEDADES DIGESTIVAS 2004; 96:201-14. [PMID: 15053735 DOI: 10.4321/s1130-01082004000300006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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234
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Casado AI, Ruiz J, Oro J, Martínez C, Fernández I, Oliva P. Anaesthetic management in a case of Kabuki syndrome. Eur J Anaesthesiol 2004; 21:162-3. [PMID: 14977351 DOI: 10.1017/s0265021504242132] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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235
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Khiar N, Araujo CS, Suárez B, Alvarez E, Fernández I. Highly diastereoselective formation of C2-symmetric bis-thioglycoside Pd(ii) complexes: the role of the exo anomeric effect. Chem Commun (Camb) 2004:714-5. [PMID: 15010795 DOI: 10.1039/b313798h] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Treatment of several C(2) symmetric bis-thioglycosides with Pd(CH(3)CN)(2)Cl(2) always leads to a single diastereomeric Pd(II) complex as a consequence of the exo-anomeric effect.
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Collado MP, Latorre E, Fernández I, Aragonés MD, Catalán RE. Endothelin-1 decreases ethanolamine plasmalogen levels and evokes PAF production in brain microvessels. Microvasc Res 2003; 66:197-203. [PMID: 14609525 DOI: 10.1016/j.mvr.2003.08.002] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Treatment of brain microvessels with Endothelin-1 evoked a decrease in ethanolamine plasmalogen levels by calcium-independent phospholipase A(2). In contrast, the diacyl molecular forms of ethanolamine phospholipids were unaffected. Evidence also shows that Endothelin type A receptors are involved. Concomitantly, PAF production mediated by CoA-independent transacylase was observed. This is the first evidence of involvement of these pathways on the Endothelin-1 mechanism of action on the blood-brain barrier.
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Goyache F, Fernández I, Royo LJ, Álvarez I, Gutiérrez JP. Factors affecting actual weaning weight, preweaning average daily gain and relative growth rate in Asturiana de los Valles beef cattle breed. Arch Anim Breed 2003. [DOI: 10.5194/aab-46-235-2003] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
Abstract
Abstract. In this paper we analyse the major environmental and genetic factors affecting actual weaning weight (WW), preweaning average daily gain (ADG) and relative growth rate (RGR) in a representative sample of field data of Asturiana de los Valles beef cattle breed. Major environmental factors affect preweaning growth performance of Asturiana de los Valles calves in the direction usually found in the literature. However RGR seems to be self-corrected for sex of calf and calving number. Heritabilities for the direct and maternal genetic effects were 0.67 and 0.29, 0.51 and 0.31 and 0.18 and 0.12 respectively for WW, ADG and RGR. The estimates of genetic parameters affecting RGR are more realistic than those estimated for the WW and ADG. Selection for RGR would lead to obtain higher growth rates and lower birth weights. RGR could be an interesting selection criterion in beef cattle improvement programs.
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Goyache F, Gutiérrez J, Alvarez I, Fernández I, Royo L, Gómez E. Genetic analysis of calf survival at different preweaning ages in beef cattle. ACTA ACUST UNITED AC 2003. [DOI: 10.1016/s0301-6226(03)00044-7] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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239
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Fernández I, Khiar N. Recent developments in the synthesis and utilization of chiral sulfoxides. Chem Rev 2003; 103:3651-705. [PMID: 12964880 DOI: 10.1021/cr990372u] [Citation(s) in RCA: 941] [Impact Index Per Article: 44.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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240
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Franco A, Martínez P, Rodríguez S, Colina F, García E, Rodrigo M, Martín A, Fernández I, Solís Herruzo JA. Liver adenomatosis. REVISTA ESPANOLA DE ENFERMEDADES DIGESTIVAS : ORGANO OFICIAL DE LA SOCIEDAD ESPANOLA DE PATOLOGIA DIGESTIVA 2003; 95:663, 662. [PMID: 14738412] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 04/28/2023]
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241
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Bobes J, Rejas J, Garcia-Garcia M, Rico-Villademoros F, García-Portilla MP, Fernández I, Hernández G. Weight gain in patients with schizophrenia treated with risperidone, olanzapine, quetiapine or haloperidol: results of the EIRE study. Schizophr Res 2003; 62:77-88. [PMID: 12765747 DOI: 10.1016/s0920-9964(02)00431-0] [Citation(s) in RCA: 84] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
OBJECTIVES The aim of this cross-sectional study, the EIRE study, was to assess the frequency of several side effects with antipsychotics in the clinical setting. This paper addresses the adverse effect of weight gain. METHOD Outpatients diagnosed of schizophrenia according to DSM-IV criteria and receiving a single antipsychotic (risperidone, olanzapine, quetiapine or haloperidol) for at least 4 weeks were consecutively recruited. Data were collected in a single visit, including data on demographic, clinical and treatment characteristics. Mean weight change was evaluated retrospectively by means of clinical charts and the weight at the time of the visit; in addition, the corresponding item of a modified version of the UKU, a Scandinavian side-effect rating scale, was used. Chi-squared test and logistic regression methods were used to analyze frequency of weight gain between treatments. RESULTS Out of 669 recruited, 636 evaluable patients were assessed. The treatment with the highest number of patients with weight gain as an adverse reaction on the UKU scale was olanzapine (74.5%), followed by risperidone (53.4%) and haloperidol (40.0%). The proportion of patients with clinically relevant weight gain (>or=7% increase versus initial weight) was also higher with olanzapine (45.7%) than with risperidone (30.6%) and haloperidol (22.4%). Five patients (13.5%) treated with quetiapine had some degree of weight gain according to the UKU scale, although no patient showed a clinically relevant weight gain (>or=7%). Treatment with olanzapine and risperidone were identified as risk factors of weight gain versus haloperidol. The risk of weight gain was higher in women (OR: 4.4), overweight patients (OR: 3.0) and in patients with <or=1 year of treatment (OR: 6.3) in the olanzapine group. A higher risk of weight gain in women (OR: 2.6) was also seen with risperidone. CONCLUSION Clinically relevant weight gain is clearly associated with olanzapine, and to lesser extent, with haloperidol and risperidone. Data for quetiapine were not conclusive because of the short duration of treatment.
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Collado MP, Latorre E, Fernández I, Aragonés MD, Catalán RE. Brain microvessel endothelin type A receptors are coupled to ceramide production. Biochem Biophys Res Commun 2003; 306:282-5. [PMID: 12788101 DOI: 10.1016/s0006-291x(03)00927-6] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Treatment of brain microvessels with endothelin-1 evoked an early decrease in the sphingomyelin levels concomitantly with an increase in those of ceramides. These responses were time- and concentration-dependent. Evidence also shows that endothelin type A receptors are involved. This is the first report on the involvement of an agonist in the regulation of the ceramide signal transduction system on blood-brain barrier and shows a new pathway likely involved in the regulation of the cerebral microvascular functioning.
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Gómez Seco J, Rodríguez Nieto MJ, Heili S, Sabillón O, Fernández I, Ortega A, González Mangado N. Fiabilidad de los sistemas de Venturi en la oxigenoterapia. Arch Bronconeumol 2003. [DOI: 10.1157/13048601] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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244
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Gómez Seco J, Rodríguez Nieto MJ, Heili S, Sabillón O, Fernández I, Ortega A, González Mangado N. [Reliability of Venturi oxygen therapy systems]. Arch Bronconeumol 2003; 39:256-60. [PMID: 12797941 DOI: 10.1016/s0300-2896(03)75377-0] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Venturi systems are among the most widely used devices for delivering oxygen therapy. Nevertheless, rigorous quality control of their reliability is lacking. In this study we used mass spectrometry to evaluate Venturi systems sold by various companies in Spain. We also studied tolerance under various conditions (changes in oxygen flow and with increased system resistance). Fixed systems were found to comply well with recommendations, whereas none of the variable systems complied. One system (Oxigem Variable) was unable to provide an oxygen concentration below 31% when set to deliver at 24% to 28%. We conclude that the variable masks available in Spain do not comply with European Union recommendations and the range of error of one of them (Oxigem Variable) means it is not clinically useful. Fixed systems were the most reliable ones in our market, and airlife and intersurgical devices were the variable systems that best approximated the reliability of fixed systems.
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Berthier ML, Hinojosa J, Martín MDC, Fernández I. Open-label study of donepezil in chronic poststroke aphasia. Neurology 2003; 60:1218-9. [PMID: 12682346 DOI: 10.1212/01.wnl.0000055871.82308.41] [Citation(s) in RCA: 52] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
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Fernández I, Muñoz R, Solís-Herruzo JA. Treatment for hepatitis C in patients infected with human immunodeficiency virus. REVISTA ESPANOLA DE ENFERMEDADES DIGESTIVAS : ORGANO OFICIAL DE LA SOCIEDAD ESPANOLA DE PATOLOGIA DIGESTIVA 2003; 95:287-91, 282-6. [PMID: 12826005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 03/03/2023]
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247
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Fernández I, Castellano G, de Salamanca RE, Colina F, Gómez de la Cámara A, Morán MJ, Muñoz R, Solís-Herruzo JA. Porphyria cutanea tarda as a predictor of poor response to interferon alfa therapy in chronic hepatitis C. Scand J Gastroenterol 2003; 38:314-9. [PMID: 12737448] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/09/2022]
Abstract
BACKGROUND Porphyria cutanea tarda (PCT) is sometimes associated with hepatitis C virus chronic infection. The aim of this study was to describe the effect of interferon alfa (IFN-alpha) in the treatment of patients with chronic hepatitis C and PCT. METHODS We treated a total of 66 patients with chronic hepatitis C with IFN-alpha 2b (5 MU t.i.w.) for 12 months. Twenty-two of these patients suffered from PCT as well. These patients differed from patients without PCT in that they were men, past history of alcohol abuse and HFE gene mutations were more common and the source of infection was almost always unknown. RESULTS Sustained virologic response was obtained in 19.7% of the 66 treated patients, 27.3% in the non-PCT group and 4.5% in the PCT group (P < 0.05). This difference could not be ascribed to the difference in sex of patients, history of alcohol abuse, HCV genotype or iron status. CONCLUSION Multivariate logistic regression analysis revealed that PCT is independently and significantly associated with non-sustained response to IFNalpha therapy. In conclusion, patients with chronic hepatitis C and PCT rarely responded to IFNalpha treatment.
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Fernández I, Castellano G, de Salamanca RE, Colina F, de la Cámara AG, Morán MJ, Muñoz R, Solís-Herruzo JA. Porphyria cutanea tarda as a Predictor of Poor Response to Interferon Alfa Therapy in Chronic Hepatitis C. Scand J Gastroenterol 2003; 38:314-319. [PMID: 28248596 DOI: 10.1080/00365520310000672a] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
BACKGROUND Porphyria cutanea tarda (PCT) is sometimes associated with hepatitis C virus chronic infection. The aim of this study was to describe the effect of interferon alfa (IFN-a) in the treatment of patients with chronic hepatitis C and PCT. METHODS We treated a total of 66 patients with chronic hepatitis C with IFN-a 2b (5 MU t.i.w.) for 12 months. Twenty-two of these patients suffered from PCT as well. These patients differed from patients without PCT in that they were men, past history of alcohol abuse and HFE gene mutations were more common and the source of infection was almost always unknown. RESULTS Sustained virologie response was obtained in 19.7% of the 66 treated patients, 27.3% in the non-PCT group and 4.5% in the PCT group (P < 0.05). This difference could not be ascribed to the difference in sex of patients, history of alcohol abuse, HCV genotype or iron status. CONCLUSION Multivariate logistic regression analysis revealed that PCT is independently and significantly associated with non-sustained response to IFNa therapy. In conclusion, patients with chronic hepatitis C and PCT rarely responded to IFNa treatment.
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Khiar N, Fernández I, Araújo CS, Rodríguez JA, Suárez B, Alvarez E. Highly diastereoselective oxidation of 2-amino-2-deoxy-1-thio-beta-D-glucopyranosides: synthesis of imino sulfinylglycosides. J Org Chem 2003; 68:1433-42. [PMID: 12585884 DOI: 10.1021/jo026519q] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
A synthetic route to imino thioglycosides and to imino sulfinylglycosides has been developed. A detailed study on the diastereoselective oxidation of 2-amino-2-deoxy-1-thio-beta-D-glucopyranosides is reported. It has been shown that the stereochemical outcome of the oxidation is highly dependent on the protective group of the amine function. While the oxidation of iminothioglycosides is slightly diastereoselective (up to 30% de in favor of the R(S) sulfoxide), a single isomer is obtained in the case of tetrachlorophthalimido derivatives. The absolute configuration of the sulfinyl glycoside was ascertained by NMR analysis using our recent model on the basis of the exo-anomeric effect corroborated by X-ray crystallography.
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Latorre E, Collado MP, Fernández I, Aragonés MD, Catalán RE. Signaling events mediating activation of brain ethanolamine plasmalogen hydrolysis by ceramide. EUROPEAN JOURNAL OF BIOCHEMISTRY 2003; 270:36-46. [PMID: 12492473 DOI: 10.1046/j.1432-1033.2003.03356.x] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Ceramide is a lipid second messenger that acts on multiple-target enzymes, some of which are involved in other signal-transduction systems. We have previously demonstrated that endogenous ceramide modifies the metabolism of brain ethanolamine plasmalogens. The mechanism involved was studied. On the basis of measurements of breakdown products, specific inhibitor effects, and previous findings, we suggest that a plasmalogen-selective phospholipase A2 is the ceramide target. Arachidonate-rich pools of the diacylphosphatidylethanolamine subclass were also affected by ceramide, but the most affected were plasmalogens. Concomitantly with production of free arachidonate, increased 1-O-arachidonoyl ceramide formation was observed. Quinacrine (phospholipase A2 inhibitor) and 1-O-octadecyl-2-O-methyl-rac-glycerol-3-phosphocholine (CoA-independent transacylase inhibitor) prevented all of these ceramide-elicited effects. Therefore, phospholipase and transacylase activities are tightly coupled. Okadaic acid (phosphatase 2A inhibitor) and PD 98059 (mitogen-activated protein kinase inhibitor) modified basal levels of ceramide and sphingomyelinase-induced accumulation of ceramide, respectively. Therefore, they provided no evidence to determine whether there is a sensitive enzyme downstream of ceramide. The evidence shows that there are serine-dependent and thiol-dependent enzymes downstream of ceramide generation. Furthermore, experiments with Ac-DEVD-CMK (caspase-3 specific inhibitor) have led us to conclude that caspase-3 is downstream of ceramide in activating the brain plasmalogen-selective phospholipase A2.
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