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C Sanz

Publications and source records attributed to C Sanz.

At least 19 recordsLinked to original sources
PubMed2006

Promoter genetic variants of prostanoid DP receptor (PTGDR) gene in patients with asthma.

BACKGROUND: PTGDR gene has been identified as an asthma-susceptibility gene. Recently, functional genetic variants have been associated with asthma. The objective of this work was to study -549T>C, -441C>T and -197T>C PTGDR promoter polymorphisms in a Spanish population. METHODS: In this study, 197 Caucasian individuals were included. Asthma was specialist-physician diagnosed according to the American Thoracic Society (ATS) criteria and classified following the Global Initiative for Asthma (GINA) guidelines. Skin prick tests were performed in all patients. The polymorphisms were analyzed by direct sequencing. RESULTS: -197T>C polymorphism was significantly associated with asthma [Fisher's P-value = 0.007, Monte Carlo P-value (10(4) simulations) = 0.004]. Multivariate analysis adjusted for age and sex confirmed this association with an increased risk of asthma (OR, 3.06; 95% CI, 1.28-7.32; P-value = 0.012). CCT CCC diplotype was associated with asthma (P-value < 0.0001; OR, 1.15; 95% CI, 1.07-1.23), specifically with allergic asthma (P-value < 0.0001). CCT CCC diplotype is unambiguous. All individuals carrying this diplotype had asthma. CONCLUSION: We identified a specific promoter variant of PTGDR that could be associated with asthma. This diplotype is a combination of the two highest transcriptional efficiency haplotypes, recently described. Our in vivo results would support for the first time what was demonstrated in vitro about high-transcriptional efficiency PTGDR haplotypes in asthma.

Adult↗
PubMed2006

Analysis of 927T> C CYSLTRI and -444A > C LTC4S polymorphisms in patients with asthma.

BACKGROUND: The cysteinyl leukotrienes (cys-LTs) are proinflammatory mediators synthesized through the 5-lipoxygenase pathway of arachidonic acid metabolism. Cys-LTs exert their biological action by binding two types of G-protein-coupled seven transmembrane receptors, CYSLTR1 and CYSLTR2. The contribution of the cys-LT receptors to bronchial asthma has been established by the therapeutic efficacy of biosynthetic inhibitors and selective CYSLTR1 blockers. OBJECTIVE: The present study was designed to analyse two different polymorphisms 927T>C CYSLTR1 and -444A>C LTC4S, and to determine whether there is an association between these polymorphisms and the asthma phenotype in a Spanish population. METHODS: Both single nucleotide polymorphisms (SNPs) were analysed in 208 individuals (130 asthmatic subjects and 78 controls). A standardized history, physical examination, skin prick tests and lung function measurement were taken from all patients. Genotypes were determined by direct sequencing after polymerase chain reaction (PCR) amplification. RESULTS: In the group of male patients, the C allele of 927T> C CYSLTRI was more common among patients with asthma than controls. No association was detected between the -444A> C LTC4S polymorphism and the asthma phenotype. The combination of 927T CYSLTR1 and -444A LTC4S was less common in male patients with asthma than in controls (Fisher's P-value =.039; Monte Carlo P-value (after 104 simulations)= .045 and the combination of 927C CYSLTR1 and -444A LTC4S was slightly more frequent in patients with asthma. No differences were observed in the female group. CONCLUSIONS: The results suggest a certain trend of associations that could help to explain some controversial results in association studies of these genes from the leukotriene pathway, when considered individually. Further studies are needed to confirm such an association.

Adolescent↗
PubMed2004

Methylene blue-photoinactivated plasma vs. fresh-frozen plasma as replacement fluid for plasma exchange in thrombotic thrombocytopenic purpura.

BACKGROUND AND OBJECTIVES: Plasma exchange with fresh-frozen plasma (FFP) is the treatment of choice in thrombotic thrombocytopenic purpura (TTP). Methylene blue-photoinactivated plasma (MBPIP) has been proposed as a safer alternative to FFP, but its effectiveness in the treatment of TTP is not well established. The purpose of this study was to investigate whether MBPIP is as effective as FFP in the treatment of TTP by plasma exchange. MATERIALS AND METHODS: A retrospective analysis was carried out of 56 TTP episodes, occurring between 1990 and 2003, which had been treated by plasma exchange. MBPIP was used for fluid replacement in 27 episodes and FFP in 29. The effect of plasma (MBPIP or FFP) on treatment outcomes was analysed by multivariate logistic regression. RESULTS: Compared to patients treated with FFP, those receiving MBPIP had an increased risk of dying from progressive TTP [adjusted odds ratio (OR) = 31; 95% confidence interval (CI): 1.2 to > 100], a greater number of recurrences while on plasma exchange therapy (OR = 4.6; 95% CI: 1.2-17), and a lower probability of attaining a sustained remission within 9 days of starting plasma exchange (OR = 5.2; 95% CI: 1.3-20). CONCLUSIONS: MBPIP seems to be less effective than FFP in the treatment of TTP. It is therefore prudent to avoid MBPIP until therapeutic equivalency to FFP has been established by randomized, controlled trials.

Adult↗
PubMed2001

Contribution of extracellular Glu residues to the structure and function of bacteriorhodopsin. Presence of specific cation-binding sites.

Single and multiple mutants of extracellular Glu side chains of bacteriorhodopsin were analyzed by acid and calcium titration, differential scanning calorimetry, and thermal difference spectrophotometry. Acid titration spectra show that the second group protonating with Asp(85) is revealed in E204Q in the absence of Cl(-) but is not observed in the triple mutant E9Q/E194Q/E204Q or in the quadruple mutant E9Q/E74Q/E194Q/E204Q. The results point to Glu(9) as the second group protonating cooperatively with Asp(85). Comparison of the apparent pK(a) of Asp(85) protonation in water and in the deionized forms and results of calcium titration suggest that cation-binding sites are of low affinity in the multiple Glu mutants. Like for deionized wild type bacteriorhodopsin, differential scanning calorimetry reveals a lack of the pretransition in the multiple mutants, whereas in E9Q it appears at lower temperature and with lower cooperativity. Additionally, at neutral pH the band at 630 nm arising from cation release upon temperature increase is absent for the multiple mutants. Based on these results, we propose the presence of two cation-binding sites in the extracellular region of bacteriorhodopsin having as ligands Glu(9), Glu(194), Glu(204), and water molecules.

Bacteriorhodopsins↗
PubMed2001

Hydroperoxide lyase depletion in transgenic potato plants leads to an increase in aphid performance.

Hydroperoxide lyases (HPLs) catalyze the cleavage of fatty acid hydroperoxides to aldehydes and oxoacids. These volatile aldehydes play a major role in forming the aroma of many plant fruits and flowers. In addition, they have antimicrobial activity in vitro and thus are thought to be involved in the plant defense response against pest and pathogen attack. An HPL activity present in potato leaves has been characterized and shown to cleave specifically 13-hydroperoxides of both linoleic and linolenic acids to yield hexanal and 3-hexenal, respectively, and 12-oxo-dodecenoic acid. A cDNA encoding this HPL has been isolated and used to monitor gene expression in healthy and mechanically damaged potato plants. HPL gene expression is subject to developmental control, being high in young leaves and attenuated in older ones, and it is induced weakly by wounding. HPL enzymatic activity, nevertheless, remains constant in leaves of different ages and also after wounding, suggesting that posttranscriptional mechanisms may regulate its activity levels. Antisense-mediated HPL depletion in transgenic potato plants has identified this enzyme as a major route of 13-fatty acid hydroperoxide degradation in the leaves. Although these transgenic plants have highly reduced levels of both hexanal and 3-hexenal, they show no phenotypic differences compared with wild-type ones, particularly in regard to the expression of wound-induced genes. However, aphids feeding on the HPL-depleted plants display approximately a two-fold increase in fecundity above those feeding on nontransformed plants, consistent with the hypothesis that HPL-derived products have a negative impact on aphid performance. Thus, HPL-catalyzed production of C6 aldehydes may be a key step of a built-in resistance mechanism of plants against some sucking insect pests.

Aldehyde-Lyases↗
PubMed2001

Interleukin 3-dependent activation of DREAM is involved in transcriptional silencing of the apoptotic Hrk gene in hematopoietic progenitor cells.

The apoptotic protein Hrk is expressed in hematopoietic progenitors after growth factor deprivation. Here we identify a silencer sequence in the 3' untranslated region of the hrk gene that binds to the transcriptional repressor DREAM in interleukin-3 (IL-3)-dependent hematopoietic progenitor cells, and abrogates the expression of reporter genes when located downstream of the open reading frame. In addition, the binding of DREAM to the hrk gene is reduced or eliminated when cells are cultured in the absence of IL-3 or treated with a calcium ionophore or a phosphatidylinositol 3-kinase-specific inhibitor, suggesting that both calcium mobilization and phosphorylation can regulate the transcriptional activity of DREAM. Furthermore, we have shown that DREAM is phosphorylated by a phosphatidylinositol 3-kinase-dependent, but Akt-independent pathway. In all cases, loss of the DREAM-DNA binding complex was correlated with increased levels of Hrk and apoptosis. These data suggest that IL-3 may trigger the activation of DREAM through different signaling pathways, which in turn binds to a silencer sequence in the hrk gene and blocks transcription, avoiding inappropriate cell death in hematopoietic progenitors.

3' Untranslated Regions↗
PubMed2001

Cytosolic aldolase is a ripening related enzyme in strawberry fruits (Fragaria x ananassa).

Two aldolase isoenzymes have been isolated from ripe strawberry fruits (Fragaria x ananassa cv. Camarosa and Elsanta) and partially purified by DEAE anion exchange and Sephacryl size exclusion chromatography. The isoenzymes were identified as class I cytosol and plastid aldolase on the basis of their chromatographic behavior on DEAE-cellulose columns, native molecular weight, pH optimum pattern, Km value for D-fructose-1,6-bisphosphate, tendency to be inactivated by lower pH values and SDS-PAGE subunit determination of 40 and 38 kDa, respectively. Total aldolase activity and distribution of both aldolase isoenzymes was also investigated at different stages of strawberry fruit ripening. Strawberries in the green and white ripening stage showed the same ratio of the two isoenzymes as green leaves with 15 and 8% cytosol aldolase activity, respectively. During strawberry fruit development the overall total aldolase activity decreased until the pink ripening stage and then increased due to a rise of cytosol aldolase yielding up to 75% in red strawberries. A cDNA putatively encoding the cytosolic form of aldolase in strawberry was cloned during the course of this study. Both microarray and RNA gel blot analyses showed that the cytosolic aldolase gene expression is induced during ripening as detected for the cytosolic aldolase enzyme. We suggest that induction of the cytosolic aldolase both at the levels of transcription and translation might be part of a ripening related stress response in the receptacle tissue.

Cloning, Molecular↗
PubMed2001

Antiapoptotic protein Bcl-x(L) is up-regulated during megakaryocytic differentiation of CD34(+) progenitors but is absent from senescent megakaryocytes.

OBJECTIVE: The expression of Bcl-x(L) has been shown to be regulated during the maturation process of different hematopoietic cell lineages (i.e., erythroid cells, neutrophils, monocytes/macrophages). In the present study, we examined the expression of Bcl-x(L) in megakaryocytes derived from CD34(+) progenitors and in the megakaryoblastic cell line UT7. MATERIALS AND METHODS: Expression of Bcl-x(L) was analyzed in CD41(+) cells cultured in the presence of thrombopoietin and in UT7 cells treated with phorbol diester by Western blot, flow cytometry, and immunocytochemistry analysis. Apoptosis was determined at different culture times by terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling and propidium iodide uptake. RESULTS: Bcl-x(L) but not Bcl-2 was up-regulated in the megakaryocytic population (CD41(+)) during the first 15 days of culture, which was consistent with the pattern of Bcl-x(L) expression in UT7 cells differentiated to megakaryocytes by incubation with phorbol diester. However, by day 20 of culture, the levels of Bcl-x(L) in CD41(+) cells were greatly reduced, and this expression pattern was accompanied by an increase in the number of apoptotic cells. At this culture time, we detected the presence of cytoplasmic fragments resembling proplatelets with prominent Bcl-x immunostaining, most likely due to the Bcl-x(L) isoform, in close proximity to Bcl-x(-) senescent megakaryocytes. The presence of Bcl-x(L) but not of Bcl-2 in platelets was confirmed by Western blot analysis. CONCLUSION: Although little is known regarding the functional significance of survival proteins within the megakaryocytic compartment, the changes in the Bcl-x(L) expression pattern observed in UT7 and CD41(+) cells may play a role in the survival of developing megakaryocytes and the lifespan of mature platelets.

Antigens, CD↗
PubMed2001

Optimizing headspace temperature and time sampling for identification of volatile compounds in ground roasted Arabica coffee.

Equilibration time and temperature were the factors studied to choose the best conditions for analyzing volatiles in roasted ground Arabica coffee by a static headspace sampling extraction method. Three temperatures of equilibration were studied: 60, 80, and 90 degrees C. A larger quantity of volatile compounds was extracted at 90 degrees C than at 80 or 60 degrees C, although the same qualitative profile was found for each. The extraction of the volatile compounds was studied at seven different equilibration times: 30, 45, 60, 80, 100, 120, and 150 min. The best time of equilibration for headspace analysis of roasted ground Arabica coffee should be selected depending on the chemical class or compound studied. One hundred and twenty-two volatile compounds were identified, including 26 furans, 20 ketones, 20 pyrazines, 9 alcohols, 9 aldehydes, 8 esters, 6 pyrroles, 6 thiophenes, 4 sulfur compounds, 3 benzenic compounds, 2 phenolic compounds, 2 pyridines, 2 thiazoles, 1 oxazole, 1 lactone, 1 alkane, 1 alkene, and 1 acid.

Alcohols↗
PubMed2001

Effect of high-oxygen and high-carbon-dioxide atmospheres on strawberry flavor and other quality traits.

The effect of high-oxygen atmospheres on strawberry flavor was studied. Strawberry fruits (Fragariax ananassa Duch. cv. Camarosa) were stored at 8 degrees C in four different atmospheres: air, 5% O(2)/20% CO(2), 80% O(2)/20% CO(2), and 90% O(2)/10% CO(2). Changes in several quality parameters were evaluated. Atmospheres combining high O(2) and high CO(2) were the most effective in preventing fungal growth and enhancing strawberry firmness. Other quality parameters such as color, titrable acidity, sugars and organic acids distribution, off-flavor development, and aroma were only mildly affected by superatmospheric O(2) levels. After one week of storage, unexpected high contents of off-flavor related compounds were found in the 80% O(2)/20% CO(2) and 90% O(2)/10% CO(2) atmospheres. Evidence of an altered ester biosynthesis was also found in fruits stored under these high-O(2) atmospheres. Data obtained suggest that stress induced by high CO(2) and stress induced by high O(2) have an additive effect on strawberry flavor alteration.

Carbon Dioxide↗
PubMed2001

Characterization of espresso coffee aroma by static headspace GC-MS and sensory flavor profile.

The aromas of three espresso coffee (EC) samples from different botanical varieties and types of roast (Arabica coffee, Robusta natural blend, and Robusta Torrefacto blend (special roast by adding sugar)) were studied by static headspace GC-MS and sensory flavor profile analysis. Seventy-seven compounds were identified in all of the EC samples. Among them, 13 key odorants have been quantified and correlated with their flavor notes by applying multivariate statistical methods. Some correlations have been found in the EC samples: some aldehydes with fruity flavors, diones with buttery flavors, and pyrazines with earthy/musty, roasty/burnt, and woody/papery flavors. By applying principal component analysis (PCA), Arabica and Robusta samples were separated successfully by principal component 1 (60.7% of variance), and Torrefacto and Natural Robusta EC samples were separated by principal component 2 (28.1% of total variance). With PCA, the aroma characterization of each EC sample could be observed. A very simple discriminant function using some key odorants was obtained by discriminant analysis, allowing the classification of each EC sample into its respective group with a success rate of 100%.

Coffee↗
PubMed2001

Disparity for the minor histocompatibility antigen HA-1 is associated with an increased risk of acute graft-versus-host disease (GvHD) but it does not affect chronic GvHD incidence, disease-free survival or overall survival after allogeneic human leucocyte antigen-identical sibling donor transplantation.

Disparity for the minor histocompatibility antigen HA-1 between patient and donor has been associated with an increased risk of acute graft-versus-host disease (GvHD) after allogeneic human leucocyte antigen (HLA)-identical sibling donor stem cell transplantation (SCT). However, no data concerning the impact of such disparity on chronic GvHD, relapse or overall survival are available. A retrospective multicentre study was performed on 215 HLA-A2-positive patients who received an HLA-identical sibling SCT, in order to determine the differences in acute and chronic GvHD incidence on the basis of the presence or absence of the HA-1 antigen mismatch. Disease-free survival and overall survival were also analysed. We detected 34 patient-donor pairs mismatched for HA-1 antigen (15.8%). Grades II-IV acute GvHD occurred in 51.6% of the HA-1-mismatched pairs compared with 37.1% of the non-mismatched. The multivariate logistic regression model showed statistical significance (P: 0.035, OR: 2.96, 95% CI: 1.07-8.14). No differences were observed between the two groups for grades III-IV acute GvHD, chronic GvHD, disease-free survival or overall survival. These results confirmed the association between HA-1 mismatch and risk of mild acute GvHD, but HA-1 mismatch was not associated with an increased incidence of chronic GvHD and did not affect relapse or overall survival.

Acute Disease↗
PubMed2001

Platelet-specific antibodies in HLA-immunized patients receiving chronic platelet support.

BACKGROUND: In HLA-alloimmunized patients, the unexpected failure of HLA-matched platelet transfusions usually raises the suspicion about concomitant platelet-specific antibodies. As the reported frequency of platelet-specific antibodies in multitransfused patients varies widely, the aim of this study was to determine the prevalence of such antibodies in a population of chronic thrombocytopenic patients with HLA antibodies. STUDY DESIGN AND METHODS: From 1985 to 1997, 11,777 determinations of HLA antibodies were performed in 1330 hematologic patients receiving chronic platelet support. Fifty-two patients with HLA alloimmunization that lasted more than 1 month were selected. The search for platelet-specific antibodies was performed by using a monoclonal antibody immobilization of platelet antigens assay, thus allowing the identification of platelet-specific antibodies directed against the platelet glycoproteins (GP) Ib/IX, GPIIb/IIIa, and GPIa/IIa. Specificity of the platelet-specific antibodies was further investigated by using a solid-phase assay with chloroquine-treated platelets. RESULTS: Only 2 (3.8%) of the 52 patients had platelet-specific antibodies. One antibody reacted with an epitope of the GPIIb/IIIa that was present in all the panel platelets, and that probably was an autoantibody. The other was an anti-HPA-5b. CONCLUSIONS: The prevalence of platelet-specific antibodies in patients with HLA alloimmunization is very small. The search for concomitant platelet-specific antibodies would be indicated only when other causes of refractoriness to HLA-matched platelets are ruled out.

HLA Antigens↗
PubMed2000

c-Raf regulates cell survival and retinal ganglion cell morphogenesis during neurogenesis.

The signaling cascade Ras/Raf/mitogen-activated protein kinases modulates cell proliferation, differentiation, and survival, all key cellular processes during neural development. To better define the in vivo role of Raf during chick retinal neurogenesis, we interfered with Raf-dependent signaling during days 4.5 to 7.5 of embryonic development by expressing a dominant negative mutant of c-Raf (DeltaRaf), which blocks Ras-dependent Raf activation, and by overexpressing wild-type c-Raf. DeltaRaf expression induced an increase in cell death by apoptosis, whereas it did not affect overall cell proliferation and differentiation. In parallel, the number of Islet-1/2-positive and TUJ1-positive retinal ganglion cells were diminished in their definitive layer, whereas there was an increase in the number of mislocated Islet-1/2-positive cells. This disturbed morphogenesis correlated with a disruption of the optic fiber layer. Conversely, c-Raf overexpression caused moderate opposite effects on apoptosis. These results frame in vivo early neurogenesis processes in which c-Raf is essential.

Animals↗
PubMed2000

Specific and rapid induction of the proapoptotic protein Hrk after growth factor withdrawal in hematopoietic progenitor cells.

Hrk is a newly described proapoptotic member of the Bcl-2 family that is mainly expressed in hematopoietic tissues and cultured neurons. In this study we have examined the expression and activity of Hrk in hematopoietic progenitors. To address these issues, we used 3 growth factor-dependent murine hematopoietic cell lines, HCD-57, FDCP-Mix, and FL5.12. The expression of Hrk was undetectable in cells cultured with growth factors, but it was rapidly up-regulated on growth factor withdrawal. In contrast, the expression of Bcl-x(L) decreased and that of proapoptotic Bax, Bad, and Bak was unchanged or down-regulated after removal of growth factors. This pattern of expression correlated with the induction of apoptosis. Hrk was also up-regulated in human cell lines and in bone marrow-derived CD34(+) cells cultured in the absence of growth factors. In addition, the levels of Hrk were up-regulated after treatment with the chemotherapeutic drug etoposide. Expression of prosurvival Bcl-x(L) or Bcl-2 proteins blocked the induction of Hrk. Hrk was induced in FDCP-Mix cells treated with ionomicin in the presence of IL-3, suggesting that cytosolic calcium may regulate the expression of this proapoptotic protein. Furthermore, ectopic expression of Hrk induced cell death of hematopoietic progenitors in the presence of IL-3. Thus, Hrk is specifically and rapidly induced in hematopoietic progenitors after growth factor deprivation or treatment with chemotherapeutic drugs, and this may be sufficient to induce apoptosis in these cells. (Blood. 2000;95:2742-2747)

Antigens, CD34↗