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Antonio López

Publications and source records attributed to Antonio López.

15 recordsLinked to original sources
PubMed2006

Fatty acid profile of table olives and its multivariate characterization using unsupervised (PCA) and supervised (DA) chemometrics.

The fatty acid composition of 67 commercial presentations of table olives was determined. The most abundant fatty acids, in decreasing order of presence, were C18:1, C16:0, C18:2 n-6, and C18:0. The ranges, expressed as grams of fatty acids per 100 g of edible portion, for the different nutritional fractions were as follows: saturated fatty acids, 2.07-5.99; monounsaturated fatty acids, 5.67-19.42; polyunsaturated fatty acids, 0.52-3.87; and trans-fatty acids, 0.08-0.44. Principal component analysis of the matrix of the fatty acid composition led to the deduction of new factors. The first accounted for 55.10% of the total variance and was mainly related to C16:10, C18:0, C20:0, C22:0, C24:0, C18:1, C18:1t, and C20:1. The second factor accounted for 10.33% of variance and was related to C16:1 and C18:2 n-6. They did not permit differentiation among elaboration types or cultivars. However, discriminant analysis was successfully applied for this objective. The fatty acids that most contributed to discriminate among elaboration styles were C17:1, C18:1, C16:0, C17:0, and C18:0 (function 1) and C17:0, C17:1, C20:0, C16:0, C18:1, and C24:0 (function 2). In the case of cultivars, they were C20:0, C18:1, C17:1, C18:2 n-6, C18:1t, and C18:2t (function 1); C18:2 n-6, C18:1, C16:0, C20:0, C18:0, and C18:2t (function 2); and C17:0, C18:3 n-3, and C17:1 (function 3). Results from this study have shown differences among the fatty acid composition and fat content of the diverse commercial presentations of table olives, which can be applied in predictive and classification discriminant analysis.

Analysis of Variance↗
PubMed2005

99mTc-hexamethylpropylene amineoxime leukocyte scintigraphy in acute pancreatitis: an alternative to contrast-enhanced computed tomography?

OBJECTIVE: Contrast-enhanced computed tomography (CECT) is the most efficient imaging technique for the diagnosis and staging of acute pancreatitis (AP); its use, however, may be unfeasible in some patients as a consequence of the drawbacks of intravenous (IV) contrast material. The aim of this study was to test the utility of labeled leukocyte scintigraphy (LLS) as an alternative imaging technique to CECT for the staging of AP. METHODS: Sixty-six patients with AP were prospectively studied. All patients underwent CECT and pancreatic LLS using (99m)Tc-hexamethylpropylene amineoxime as leukocyte label within a time interval of 2 days, in the early phase of AP. In addition, all patients had their serum C-reactive protein (CRP) concentration measured within 48-72 h after admission. CECT images were analyzed for Balthazar's grade of pancreatitis and for the presence or absence of pancreatic necrosis. Scintigraphic activity of 3-4 h planar images was scored on a 0-2 scale in relation to physiological liver uptake. RESULTS: LLS score was significantly related (p < 0.001) to both components of CECT (grade of pancreatitis and pancreatic necrosis). LLS and serum CRP showed similar results for detecting the most severe pancreatic damage as showed by their respective receiver operating characteristic (ROC) curves. Sensitivities and specificities of LLS score of 2 were, respectively, 62% and 96% for the detection of grade D-E pancreatitis and 90% and 89% for the detection of pancreatic necrosis. Scintigraphic score of 2 increased the likelihood of grade D-E pancreatitis from 32% (pretest probability) to 87% (posttest probability) (likelihood ratio: 13.9) and that of pancreatic necrosis from 16% to 60% (likelihood ratio: 8.4). CONCLUSIONS: Our results show that leukocytes are related to the severity of local pancreatic damage in AP. Thus, LLS is a potential alternative technique to CECT for staging AP.

Acute Disease↗
PubMed2005

Sonographic findings in ischemic colitis in 58 patients.

OBJECTIVE: The purpose of this study was to describe the sonographic findings of 58 patients with proven ischemic colitis and to evaluate whether any of the findings are related to the presence or development of transmural necrosis. MATERIALS AND METHODS: We reviewed the histories of patients diagnosed with ischemic colitis over a period of 5.5 years. Sixty-two patients had undergone sonographic examinations. The spectrum of sonographic findings in ischemic colitis was based on the original imaging report, with an analysis of the presence of colonic abnormalities and their associated alterations. In the second part of the study, we divided the patients into two groups according to the presence or absence of transmural necrosis, and the sonographic findings of each group were compared. Ten patients had sonographic follow-up studies during their hospital stay. RESULTS: The prospective sensitivity of sonography for the characterization of colonic abnormalities was 93.5% (58/62 patients). Segmental involvement was detected in 57 of the 58 patients, with left-sided colitis in 47 (81%). The mean length of bowel involved was 19 cm, with a mean wall thickness of 7.6 mm. Colon wall stratification was preserved in 38 patients (66%). Altered pericolic fat was observed in 16 patients (28%). Absence of or barely visible color Doppler flow in the thickened bowel wall was recorded in 80% of patients. Altered pericolic fat was the only sonographic variable significantly associated with the presence of transmural necrosis (p = 0.004). Improvement as assessed on sonography was observed in all patients with a good clinical course. In patients with transmural necrosis, sonography did not show improvement. CONCLUSION: Sonography is a valuable technique for the detection of colonic abnormalities resulting from ischemic colitis. In this study, altered pericolic fat or the absence of improvement in sonographic follow-up studies were factors associated with transmural necrosis.

Aged↗
PubMed2005

Differences in anti-apoptotic and multidrug resistance phenotypes in elderly and young acute myeloid leukemia patients are related to the maturation of blast cells.

BACKGROUND AND OBJECTIVES: Elderly patients with acute myeloid leukemia (AML) have a less favorable outcome, which has been related, among other factors, to multidrug resistance (MDR) phenotypes. DESIGN AND METHODS: Freshly obtained erythrocyte-lysed bone marrow samples from 150 elderly patients (> 65 years) with de novo AML and 30 younger AML patients were analyzed using a 4-color immunofluorescence technique for quantitative expression of proteins associated with apoptosis (bcl-2, bax, APO2.7) and MDR (P-gp, MRP, LRP) in 3 blast cell subpopulations, defined according to their maturation stage. RESULTS: Although a homogeneous CD34+ blast cell population was more frequent in the elderly patients, (25% vs 7%, p=0.02), no statistically significant differences were detected between the two age groups in the expression of either apoptosis- or MDR-associated proteins, except for slightly higher quantities of LRP protein in the more immature CD34+ blast cell subset in the elderly AML cases (p=0.04). Interestingly, when different blast cell populations were compared, immature (CD34+) blast cells were characterized by higher levels of bcl-2 in both age groups and lower levels of APO2.7 in the elderly group. In addition, higher P-gp levels were found in CD34+ blast cells than in CD34-- ones in elderly AML patients. Reactivity for LRP was low in both elderly and younger patients. INTERPRETATION AND CONCLUSIONS: In summary, our results suggest that the higher resistance to chemotherapy observed in elderly AML patients could be related to a higher incidence of cases with a CD34+ homogeneous blast cell population, since these blast cells frequently display a more pronounced anti-apoptotic and MDR1 phenotype.

Acute Disease↗
PubMed2004

CD34+ cells from acute myeloid leukemia, myelodysplastic syndromes, and normal bone marrow display different apoptosis and drug resistance-associated phenotypes.

Myelodysplastic syndromes and acute myeloid leukemia (AML) are heterogeneous disorders in which conflicting results in apoptosis and multidrug resistance (MDR) have been reported. We have evaluated by multiparameter flow cytometry the expression of apoptosis- (APO2.7, bcl-2, and bax) and MDR-related proteins [P-glycoprotein (P-gp), multidrug resistance protein (MRP), and lung resistance protein (LRP)] specifically on bone marrow (BM) CD34+ cells, and their major CD32-/dim and CD32+ subsets, in de novo AML (n=90), high-risk myelodysplastic syndrome (n=9), and low-risk myelodysplastic syndrome (n=21) patients at diagnosis, and compared with normal BM CD34+ cells (n=6). CD34+ myeloid cells from AML and high-risk myelodysplastic syndrome patients displayed higher expression of bcl-2 (P <0.0001) and lower reactivity for APO2.7 (P=0.002) compared with low-risk myelodysplastic syndrome and normal controls. Similar results applied to the two predefined CD34+ myeloid cell subsets. No significant differences were found in the expression of P-gp, MRP, and LRP between low-risk myelodysplastic syndrome patients and normal BM, but decreased expression of MRP (P <0.03) in AML and high-risk myelodysplastic syndromes and P-gp (P=0.008) in high-risk myelodysplastic syndromes were detected. Hierarchical clustering analysis showed that low-risk myelodysplastic syndrome patients were clustered next to normal BM samples, whereas high-risk myelodysplastic syndromes were clustered together and mixed with the de novo AML patients. In summary, increased resistance to chemotherapy of CD34+ cells from both AML and high-risk myelodysplastic syndromes would be explained more appropriately in terms of an increased antiapoptotic phenotype rather than a MDR phenotype. In low-risk myelodysplastic syndromes abnormally high apoptotic rates would be restricted to the CD34- cell compartments.

ATP Binding Cassette Transporter, Subfamily B, Mem↗
PubMed2004

Immunophenotypic analysis of mast cells in mastocytosis: When and how to do it. Proposals of the Spanish Network on Mastocytosis (REMA).

BACKGROUND: Mastocytosis is a term used for a heterogeneous group of disorders characterized by an abnormal proliferation and accumulation of mast cells (MCs) in one or multiple tissues including skin, bone marrow, liver, spleen, and lymph nodes, among others. METHODS: In recent years, multiparameter flow cytometric studies have shown that pathologic MCs from patients with mastocytosis display unique aberrant immunophenotypic characteristics as compared with normal MCs. RESULTS: Among other features, pathologic MCs show aberrant expression of CD25 and CD2 antigens and abnormally high levels of the CD11c and CD35 complement receptors, the CD59 complement regulatory molecule, the CD63 lysosomal membrane antigen, and the CD69 early-activation antigen. In addition, MCs from mastocytosis express abnormally low levels of CD117 and unexpectedly high light scatter and autofluorescence characteristics. CONCLUSIONS: These aberrant immunophenotypic features are of great relevance for the assessment of tissue involvement in mastocytosis with consequences in the diagnosis, classification, and follow-up of the disease and in its differential diagnosis with other entities. In this paper we provide the reader with information for the objective and reproducible identification of pathologic MCs by using quantitative multiparametric flow cytometry, information for their phenotypic characterization, and the criteria currently used for a correct interpretation of the immunophenotypic results obtained.

Antibodies, Monoclonal↗
PubMed2004

Intratumoral patterns of clonal evolution in meningiomas as defined by multicolor interphase fluorescence in situ hybridization (FISH): is there a relationship between histopathologically benign and atypical/anaplastic lesions?

Meningiomas are cytogenetically heterogeneous tumors in which chromosome gains and losses frequently occur. Based on the intertumoral cytogenetic heterogeneity of meningiomas, hypothetical models of clonal evolution have been proposed in these tumors which have never been confirmed at the intratumoral cell level. The aim of this study was to establish the intratumoral patterns of clonal evolution associated with chromosomal instability in individual patients as a way to establish tumor progression pathways in meningiomas and their relationship with tumor histopathology and behavior. A total of 125 meningioma patients were analyzed at diagnosis. In all cases, multicolor interphase fluorescence in situ hybridization (iFISH) studies were performed on fresh tumor samples for the detection of quantitative abnormalities for 11 different chromosomes. In addition, overall tumor cell DNA content was measured in parallel by flow cytometry. iFISH studies were also performed in parallel on tissue sections in a subset of 30 patients. FISH studies showed that 56 (45%) of the 125 cases analyzed had a single tumor cell clone, all these cases corresponding to histologically benign grade I tumors. In the remaining cases (55%) more than one tumor cell clone was identified: two in 45 cases (36%), three in 19 (15%), and four or more clones in five cases (4%). Overall, flow cytometric analysis of cell DNA contents showed the presence of DNA aneuploidy in 44 of these cases (35%), 30% corresponding to DNA hyperdiploid and 5% to hypodiploid cases; from the DNA aneuploid cases, 35 (28%) showed two clones and 9 (7%) had three or more clones. A high degree of correlation (r >/= 0.89; P < 0.001) was found between FISH and flow cytometry as regards the overall quantitative DNA changes detected with both techniques, the former being more sensitive. Among the cases with chromosome abnormalities, the earliest tumor cell clone observed was frequently characterized by the loss of one or more chromosomes (64% of all meningiomas); loss of either a single chromosome 22 or, less frequently, of a sex chromosome (X or Y) and del (1p) was commonly found as the single initial cytogenetic aberration (30%, 5%, and 5% of the cases, respectively). Interestingly, an isolated loss of chromosome 22 was only found as the initial abnormality in one out of 14 atypical/anaplastic meningiomas, while the same cytogenetic pattern was present in the ancestral tumor cell clone of 32% of the benign tumors. Cytogenetic patterns based on chromosome gains were found in the ancestral tumor cell clone in 4% of the patients, 2% corresponding to tetraploid tumors. Overall, cytogenetic evolution of the earliest tumor cell clones was frequently associated with tetraploidization (31%). Our results show that meningiomas are genetically heterogeneous tumors that display different patterns of numerical chromosome changes, with the presence of more than one tumor cell clone detected in almost half of the cases including all atypical/anaplastic cases. Interestingly, the pathways of intratumoral clonal evolution observed in the benign tumors were different from those observed in atypical/anaplastic meningiomas, suggesting that the latter tumors might not always represent a more advanced stage of histologically benign meningiomas.

Adolescent↗
PubMed2004

Imagery factors in the Spanish version of the Verbalizer-Visualizer Questionnaire.

The factor structure and internal consistency reliability of the Spanish version of the Verbalizer-Visualizer Questionnaire was analyzed. 969 male and female high school students completed the questionnaire and the Gordon Test of Visual Imagery Control. Factor analysis indicated that the questionnaire comprises five factors: "interest in words," "dream vividness and frequency," "verbal fluency," "task performance difficulty," and "ways of thinking and acting." The internal consistency was very low (Cronbach alpha = .30). The correlation between scores and those on the Gordon test was statistically significant because N was large but very weak (r =.08, p<.05). The questionnaire measured five distinct factors, and this should be taken into account when using the Spanish version rather than a coherent dimension.

Adolescent↗
PubMed2003

Overexpression of complement receptors and related antigens on the surface of bone marrow mast cells in patients with systemic mastocytosis.

Depending on their stage of maturation and other factors, mast cell (MC) subsets differ from each other in terms of the expression of complement-associated antigens. This study analysed the expression of various complement-related cell surface antigens (CD11b/CR3, CD11c/CR4, CD35/CR1, CD55/DAF, CD59/MIRL, CD88/C5aR) on bone marrow mast cells (BMMC) in patients suffering from systemic mastocytosis (SM), other haematological diseases and non-haematological disorders (control groups). Expression of complement-associated cell surface antigens was analysed by flow cytometry. There were clear immunophenotypic differences between BMMC obtained from patients with SM and those from the control subjects: the percentage of patients expressing surface CD11c, CD35 and CD88 was significantly higher in patients with SM (76%, 100%, 54%) than in the control subjects (58%, 11%, 18%) (P < 0.05). In addition, the levels of CD11c, CD35 and CD88 expressed per MC (sites per cell) were significantly higher (P < 0.05) in SM than in the control group. Expression of the complement regulatory molecules CD55 and CD59 was detected in BMMC in all patients analysed. However, the levels of CD59 per BMMC were higher in patients with SM as compared with the control subjects, which could help to explain the formation of BMMC aggregates in the former group of individuals. Together, our results showed that BMMC in systemic mastocytosis overexpressed the cell surface membrane receptors involved in binding of complement components and complement-mediated cell activation. Whether this pathological expression of complement receptors is of pathophysiological significance remains to be determined.

Adult↗
PubMed2003

Immunophenotypic analysis of myelodysplastic syndromes.

BACKGROUND AND OBJECTIVES: In contrast with hematologic malignancies in which the value of immunophenotypic studies is well established, information on the immunophenotypic characteristics of myelodysplastic syndromes (MDS) is scanty. The main goal of the present study was to explore the immunophenotypic differences between patients with MDS and normal individuals, including changes in distribution of cell lineages as well as phenotypic aberrations and blockades in cell maturation pathways. DESIGN AND METHODS: In MDS the proportion of bone marrow CD34+ cells was higher than in normal patients but the most immature progenitors (CD34+CD38-) were less represented. By contrast the proportion of myelomonocytic CD34+ cells was greater than in normal individuals, translating into an increased myeloid/non-myeloid CD34+ hematopoietic progenitor cell ratio. RESULTS: This suggests that in MDS, the majority of CD34+ cells are already committed to the myeloid lineage. Upon analyzing the granulo-monocytic differentiation pathway, MDS patients showed an increased proportion of monocytic cells with a decreased percentage of cells of neutrophil lineage, leading to a lower neutrophil/monocytic cell ratio. Maturational arrests in the monocytic but not in the neutrophil differentiation pathway were observed. In refractory anemia with excess blasts in transformation (RAEB-t) such blockades mainly occurred during the earliest stages of differentiation but in the other MDS subtypes they occurred in later stages. INTERPRETATION AND CONCLUSIONS: Phenotypic aberrations occurred in 90% of patients and a high proportion of cases showed >=2 aberrations. In summary, our results show that, in addition to an abnormal distribution of the bone marrow cell compartment, MDS patients frequently show aberrant phenotypes and maturational arrests. Some of these features may help in cases in which the diagnosis of MDS is questionable.

Bone Marrow Cells↗
PubMed2002

Comparative analysis of different flow cytometry-based immunophenotypic methods for the analysis of CD59 and CD55 expression on major peripheral blood cell subsets.

BACKGROUND: Flow cytometry-based immunophenotypic techniques for the analysis of CD55 and CD59 expression on the major cell populations present in blood are the preferred method for the diagnostic screening of paroxysmal nocturnal hemoglobinuria (PNH). METHODS: In the present study, we comparatively analyze the effects of stain-lyse-and-then-wash techniques and lyse-wash-and-then-stain procedures on the detection of both CD55 and CD59 expression on the major peripheral blood (PB) leucocyte subsets, as analyzed by flow cytometry. Our major goal was to establish the minimum amounts of anti-CD55 and anti-CD59 reagents required to be added to a minimum volume of blood, which would allow an optimal staining for both antigens on red cells, platelets, and leucocytes present in a single tube. RESULTS: Our results show that upon comparing stain-lyse-and-then-wash techniques with lyse-wash-and-then-stain protocols, the presence of important amounts of red cells at the time peripheral blood leucocytes are stained for CD55 and CD59 is associated with a significantly (P < 0.01) lower and more heterogeneous pattern of antigen expression on almost all major PB leucocyte subsets, supporting the need to use red cell lysing procedures prior to the staining of leucocytes. Identical, optimal patterns of antigen staining for CD55 and CD59 were obtained upon incubating 3 microL of blood with 10 microL of each of these monoclonal antibody (mAb) reagents (protein concentration of 0.05 microg/microL and 0.2 microg/microL respectively) for 30 min (room temperature [RT]) using a non-lyse-non-wash sample preparation procedure. This latter procedure allowed for the simultaneous analysis of CD55 and CD59 expression on red cells, platelets, neutrophils, monocytes, and lymphocytes present in the sample through the combined staining of CD55 and CD59 with CD64-fluorescein isothiocyante (FITC) plus CD61-peridinin chlorophyll protein (PerCP) and CD45-PerCP. CONCLUSIONS: In summary, our results show that the sample preparation protocol has a significant impact on the quality of the staining obtained for the CD55 and CD59 antigens on the major PB leucocyte subsets; additionally, we propose a simple and reliable stain-non-lyse-non-wash method for the simultaneous analysis of CD55 and CD59 expression on PB red cells, platelets, neutrophils, monocytes, and lymphocytes, which could be reached through the use of two triple stainings.

Blood Cells↗
PubMed2002

Neuropeptides bombesin and calcitonin inhibit apoptosis-related elemental changes in prostate carcinoma cell lines.

BACKGROUND: Etoposide-induced apoptosis in prostate carcinoma cells is associated with changes in the elemental content of the cells. The authors previously reported that calcitonin and bombesin inhibited etoposide-induced apoptosis in these cells. In the current study, the authors investigated whether these neuropeptides block the etoposide-induced changes in elemental content. METHODS: Cells from the PC-3 and Du 145 prostate carcinoma cell lines were grown either on solid substrates or on thin plastic films on titanium electron microscopy grids, and they were exposed to etoposide for 48 hours in the absence or presence of calcitonin and bombesin. After the exposure, the cells were frozen and freeze dried, and their elemental content was analyzed by energy-dispersive X-ray microanalysis in both in the scanning electron microscope and the scanning transmission electron microscope. RESULTS: Etoposide treatment consistently induced an increase in the cellular Na concentration and a decrease in the cellular K concentration, resulting in a marked increase of the Na/K ratio and also an increase in the phosphorus:sulphur (P/S) ratio. Both bombesin and calcitonin inhibited the etoposide-induced changes in the cellular Na/K ratio, and calcitonin, but not bombesin, inhibited the changes in the P/S ratio. No significant elemental changes were found with bombesin or calcitonin alone. CONCLUSIONS: The neuropeptides bombesin and calcitonin, which inhibited etoposide-induced apoptosis, also inhibited the etoposide-induced elemental changes in prostate carcinoma cells. This important fact strengthens the link between apoptosis and changes in the intracellular elemental content. This correlation provides an objective basis for the study of neuropeptide target points and may be helpful for alternative therapeutic protocols using neuropeptide inhibitors in the treatment of patients with advanced prostatic carcinoma.

Absorptiometry, Photon↗
PubMed2002

Preoperative nutritional evaluation as a prognostic tool for wound healing.

In 170 patients given primary hip or knee joint prosthesis surgery, we determined the relation between variables connected with the preoperative nutritional state and delayed healing of the surgical wound. 46 patients had a lymphocyte count of less than 1500 cells/mm3 (normal 1500-3300 cell/mm3), 18 an albumin level of less than 3.5 g/dL (normal 3.5-5 gr/dL), and 35 patients had a transferrin level of less than 200 mg/dL (normal 200-400 mg/dL). We found an association between the preoperative lymphocyte count and delay in wound healing, whereas preoperative seru albumin and transferrin levels had no significant predictive value. In addition, a preoperative lymphocyte count of less than 1500 cells/mm3 was associated with a 3 times higher frequency of healing complications.

Adult↗