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J L Fernández

Publications and source records attributed to J L Fernández.

At least 19 recordsLinked to original sources
PubMed2006

Sperm DNA fragmentation in a random sample of the Spanish boar livestock.

A collection of 180 chilled boar semen samples, randomly chosen from stocks currently used for routine characterization of standard seminal quality, were studied for DNA fragmentation status using the sperm chromatin dispersion test and the DNA fragmentation index (DFI: percent of abnormal cell versus normal cells for DNA fragmentation) was determined. Values for sperm motility, acrosome status, coiled tails and abnormal head morphology, including presence and position of cytoplasmic droplets were also obtained. The DFI in the whole sample presented a wide range of variation with values oscillating between practically 0% and 47.95% and do not fit to a normal distribution. The most frequent classes (83.3%) presented a DFI lower than a 5%. Significant correlations between sperm DNA fragmentation and sperm motility, acrosome status, frequency of distal droplets, coiled tails and abnormal head morphology, were not observed. However, the presence of proximal cytoplasmic droplets showed a significant correlation with the level of DNA fragmentation observed in the ejaculated spermatozoa.

Acrosome↗
PubMed2004

Telomeric and interstitial telomeric-like DNA sequences in Orthoptera genomes.

A (TTAGG)n-specific telomeric DNA probe was hybridized to 11 orthopteroid insect genomes by fluorescence in situ hybridization. Nine different genera, mainly distributed within two evolutionary branches with male chromosome numbers 2n = 23 and 2n = 17 were included in the analysis. Telomere sequences yielded positive signals in every telomere and there was a considerable number of interstitial telomeric-like sequences, mainly located at the distal end of some, but not all, subterminal chromosome regions. One of the species, Pyrgomorpha conica, showed massive hybridization signals associated with constitutive heterochromatin. The results are discussed along two lines: (i) the chromosomal evolutionary trends within this group of insects and (ii) the putative role that ITs may play in a genome when they are considered telomere-derived, but not telomere-functional, DNA sequences.

Animals↗
PubMed2003

[Delays in the diagnosis of lung cancer].

OBJECTIVE: To study the clinical and demographic factors associated with delays in the diagnosis of lung cancer. PATIENTS AND METHODS: A 2-year prospective study of patients admitted to the respiratory medicine ward with a suspected diagnosis of lung cancer. We studied demographic factors, health care received, place of residence, and delays in carrying out diagnostic procedures. The following diagnostic time periods were defined: consultation (from first symptom to first medical visit), middle period (from first medical visit to hospital admission) and diagnostic (from hospital admission to histological diagnosis and clinical staging). RESULTS: One hundred thirteen patients with a mean age of 65 years (range, 36-90), 103 men and 10 women, were studied. The most frequent symptoms leading to consultation were coughing (10.6%), hemoptysis (19.5%), chest pain (26.5%), and shortness of breath (9.7%). First visits were to a primary care physician for 72%, to the hospital emergency room for 22%, or to a pulmonologist for 6%. Forty-four percent of the patients visited the doctor 2 or 3 times. The mean SD, numbers of days for the different time periods were as follows: consultation, 30.3 60; diagnosis, 18.6 19; middle period 37.9 63. The mean total time from first symptom to diagnosis was 85.7 87 days. The middle period, the time in hospital until diagnosis, and the total time were shorter when patients were referred by the primary care physician to the emergency room or were directly admitted to the hospital (P<.001). Only 25.7% of the staged lung cancers were operable. CONCLUSIONS: Delays in lung cancer diagnosis are long. The attitudes of primary care physicians and their relations with specialized care providers are crucial for reducing delays.

Adult↗
PubMed2003

Intact Medtronic and Carpentier Edwards S.A.V.: clinical and hemodynamic outcomes over 13 years.

UNLABELLED: We report on 215 consecutive patients with isolated aortic replacement of which 91 received an Intact Medtronic (IM) prosthesis and 124 a Carpentier Edwards SAV. (CE). More than 50% of patients were over 70 years old. Follow-up was complete for 95% of patients. Mean follow-up was 6.04 years (16 days-13 years); a total of 1244 patient-years (IM 6.61years, 590 patient-years, CE 5.95 years, 670 patient-years). RESULTS: the following results are expressed for IM and CE groups respectively. Early mortality: 3.3% and 8.13%. Late mortality: 23 and 27 patients. Survival at 13 years: 53.31+/-7.63% and 47.47+/-7.9%. Major thromboembolism: 0.34% and 0.30% per patient-year. SVD: 0.16% and 0.14% per patient-year. Endocarditis: 0.33% and 0.29%. Re-operation: 0.5% and 0.44%. Over 95% of patients are re-operation free at 13 years. CONCLUSION: Intact and Carpentier valves had similar durability and clinical/hemodynamic results. Both have proved excellent aortic valve substitutes in elderly patients.

Adult↗
PubMed2003

Prospective randomised phase II study of docetaxel versus paclitaxel administered weekly in patients with non-small-cell lung cancer previously treated with platinum-based chemotherapy.

BACKGROUND: Docetaxel and paclitaxel have activity in the second-line treatment of non-small-cell lung cancer (NSCLC), and can be administered as weekly schedules. This phase II randomised study was designed to test the efficacy and toxicity of both taxanes in patients with NSCLC previously treated with platinum-based chemotherapy. PATIENTS AND METHODS: Patients (n = 71) with documented NSCLC were randomised to receive docetaxel (n = 35 patients; 36 mg/m(2)) or paclitaxel (n = 36 patients; 80 mg/m(2)) as a 1 h weekly infusion for 6 weeks followed by a 2-week rest. The cycles were repeated until disease progression or non-acceptable toxicities occurred. RESULTS: Treatment achieved partial response of one versus five patients, median time-to-progression of 74 versus 68 days, and overall survival of 184 versus 105 days, with docetaxel and paclitaxel, respectively. The most common non-haematological toxicities were (docetaxel versus paclitaxel): grade 3/4 pulmonary toxicity in seven versus one patient; grade 2/3 diarrhoea in nine versus five; and grade 3/4 haematological toxicities occurred in two versus four patients. There were no treatment-related deaths. CONCLUSIONS: Docetaxel and paclitaxel administered weekly have discrete efficacy in patients with NSCLC previously treated with platinum-based chemotherapy. The higher non-haematological toxicity of docetaxel, particularly pulmonary toxicity and diarrhoea, is of concern and warrants further investigation.

Adult↗
PubMed2003

Phase II study of weekly irinotecan (CPT-11) as second-line treatment of patients with advanced colorectal cancer.

This phase II trial studied the antitumor effect and toxicity of weekly irinotecan (CPT-11, 125 mg/m(2) 60 min iv infusion, weekly for 4 wk plus 2 wk rest) as second-line chemotherapy in patients with advanced colorectal cancer (CRC) resistant or refractory to prior 5-fluorouracil (5-FU) therapy. Sixty-nine patients with adenocarcinoma (57% in the colon and 43% in the rectum) were enrolled. The median number of treatment cycles received per patient was 4 (range, 1-6). Overall response rate was 18% (95% CI, 9-26), with 4 complete responses (6%) and 8 partial responses (12%), and a median duration of response of 8.1 mo (95% CI, 4.2-12.1). Stable disease was observed in 19 patients (28%). The median time to disease progression was 5.2 mo (95% CI, 4.3-6.1), and the median overall survival was 13.3 mo (95% CI, 9.8-16.8 months). The toxicity profile was favorable: grade 3/4 delayed diarrhea was observed in 10 patients (14.5%) in one cycle each, and grade 3/4 neutropenia in 6 patients (8.7%) and 6 cycles (3.3%). No febrile neutropenia or infection was documented. Grade 3/4 nausea and vomiting were reported in 1 (1.4%) and 7 patients (10.1%), respectively. In conclusion, this phase II trial showed a response rate and a toxicity profile of weekly CPT-11 in line with the results of prior phase II studies.

Adenocarcinoma↗
PubMed2002

Determinant parameters and components in the storage of virgin olive oil. Prediction of storage time beyond which the oil is no longer of "extra" quality.

This work studies the changes in the quality indices standardized by the European Union, together with the evolution of the oxidative stability and sterols, polyphenols, alpha-tocopherol, pigments, and fatty acids contents throughout the storage of Picual and Hojiblanca olive cultivar "extra" virgin olive oils at 2 degrees C + darkness and 30 degrees C + illumination. Only two quality indices (K(270) and sensory evaluation) indicate the loss of the extra quality of the oil during storage, and there is an excellent correlation between initial stability and the time to reach the limit of K(270) > 0.25 (after which the oil quality is no longer of "extra" quality). This time can be predicted with an error of <10%, which is of great commercial interest and previously unknown. Also unknown until now is that the changes in polyphenols, pigments, and alpha-tocopherol with storage time follow first-order kinetics.

European Union↗
PubMed2002

Decline of high hepatitis C virus prevalence in a hemodialysis unit with no isolation measures during a 6-year follow-up.

AIMS: It has been recently suggested that isolation measures may be necessary to avoid hepatitis C virus (HCV) spread in hemodialysis units with a high HCV prevalence. To assess the variation in prevalence and long-term incidence of HCV infection, we studied our hemodialysis patients during a 6-year follow-up period. MATERIAL AND METHODS: We compared anti-HCV prevalence in 1994, 1996, 1998 and 2000 according to the anti-HCV status, and we analyzed the seroconversion of anti-HCV. Strict adherence to universal precautions has been fulfilled since 1993 and systematic anti-HCV testing in blood donors has been performed since 1994. No isolation measures were adopted. RESULTS: In 1994,22 of 53 (41.5%) patients tested positive for anti-HCV; in 1996, 18 of 67 (26.9%); in 1998,9 of 75 (12.0%); and in 2000, 7 of 82 (8.5%) (p < 0.001). In 2000, 7 of 14 (50.0%) patients who had been attending the unit since 1994 and 0 of 68 (0%) who had entered after 1994 were anti-HCV-positive (p = 0.000). Eight of 1 71 (4.7%) patients who entered the unit and 24 of 142 (16.9%) who left it were anti-HCV-positive (p < 0.001). Two patients became anti-HCV-negative. Seroconversion of anti-HCV was observed in 3 patients. The yearly seroconversion rate was 0.5% during the period 1994-1996 (1 of 98 patients at risk), 0.5% during the period 1996-1998 (1 of 91 patients at risk), and 0.4% during the period 1998-2000 (1 of 120 patients at risk). CONCLUSIONS: It was possible to reduce a high HCV prevalence in a hemodialysis unit when a low incidence was achieved without taking isolation measures. All anti-HCV-positive patients in 2000 had been undergoing hemodialysis since 1994.

Adult↗
PubMed2002

Effects of policosanol and lovastatin on lipid profile and lipid peroxidation in patients with dyslipidemia associated with type 2 diabetes mellitus.

In this pilot, randomized, double-blind study, we compared the effects of policosanol and lovastatin on lipid profile and lipid peroxidation in patients with dyslipidemia and type 2 diabetes mellitus. After 4 weeks on a cholesterol-lowering diet, 36 patients were randomized to policosanol (10 mg/day) or lovastatin (20 mg/day) tablets o.i.d. for 8 weeks. Policosanol significantly (p < 0.001) lowered serum low-density lipoprotein-cholesterol (LDL-C) (29.9%), total cholesterol (21.1%), triglycerides (13.6%) and the LDL-C/high-density lipoprotein-cholesterol (HDL-C) (36.7%) and total cholesterol/HDL-C (28.9%) ratios and significantly (p < 0.01) increased HDL-C (12.5%). Lovastatin significantly (p < 0.001) lowered LDL-C (25%), total cholesterol (18%), triglycerides (10.9%) and the LDL-C/HDL-C (30.4%) and total cholesterol/HDL-C ratios (23.9%) and significantly (p < 0.01) raised HDL-C (8.3%). Policosanol was more effective (p < 0.05) than lovastatin in reducing both ratios and in increasing (p < 0.05) HDL-C. Policosanol, but not lovastatin, significantly raised the lag time (20.9%) of Cu+2-induced LDL peroxidation and total plasma antioxidant activity (24.2%) (p < 0.05). Both policosanol and lovastatin significantly decreased the propagation rate (41.9% and 41.6% respectively, p < 0.001), maximal diene production (8.3% and 5.7%) and plasma levels of thiobarbituric acid reactive substances (9.7% and 11.5%, p < 0.001). Both treatments were well tolerated. Only one patient in the lovastatin group withdrew from the trial due to adverse events. In conclusion, policosanol and lovastatin administered short term to patients with dyslipidemia secondary to type 2 diabetes were effective in lowering cholesterol and in inhibiting the extent of lipid peroxidation. Policosanol (10 mg/day) was slightly more effective than lovastatin (20 mg/day) in reducing the LDL-C/HDL-C and total cholesterol/HDL-C ratios, in increasing HDL-C levels and in preventing LDL oxidation. Nevertheless, since this was a pilot study, further clinical studies performed in larger sample sizes of diabetic patients are needed for definitive conclusions.

Aged↗
PubMed2001

High frequency of constitutive alkali-labile sites in mouse major satellite DNA, detected by DNA breakage detection-fluorescence in situ hybridization.

DNA breakage detection-fluorescence in situ hybridization (DBD-FISH) is a new procedure for detecting and quantifying DNA breaks and alkali-labile sites in single cells. Cells trapped within an agarose matrix are deproteinized and treated with an alkaline unwinding solution that transforms DNA breaks and alkali-labile sites into single-strand DNA (ssDNA) motifs starting from the end of the break. These ssDNA motifs are susceptible to being hybridized with whole genome or specific DNA probes, and detected using current FISH procedures. As DNA breaks increase in a target region, more ssDNA is produced and more DNA probe hybridizes, thus increasing the FISH signal, which may be captured and analyzed using a digital image analysis system. This increase can be reflected in the surface area, mean and whole fluorescence intensity of the signal. When intact mouse splenocytes were processed with this technique using a whole genome probe, a very strong background signal was evident when compared with human blood leukocytes. In fact, when using 0.03M NaOH as the alkaline unwinding solution at 22 degrees C for 2.5min, the whole fluorescence intensity from mice cells was 50 times higher than that from human cells, thus suggesting the existence of a high frequency of constitutive alkali-labile sites in the DNA from mouse cells. Furthermore, when alkaline unwound mouse cells were simultaneously hybridized with the whole genome probe (FITC-revealed, green) and a major satellite DNA probe (Cy-3-labeled, red) both signals appeared co-localized. This result demonstrates that the high frequency of constitutive alkali-labile sites detected in the mouse genome is mainly located in the major satellite DNA sequences, resembling the findings from human 5bp classical satellite DNA sequences.

Alkalies↗
PubMed2001

DBD-fish on neutral comets: simultaneous analysis of DNA single- and double-strand breaks in individual cells.

Humanblood leukocytes exposed to X-rays were immersed in an agarose microgel on a slide, extensively deproteinized, and electrophoresed under neutral conditions. Following this single-cell gel electrophoresis assay, characteristics of DNA migration (i.e., area of the comet) are related to the DNA double-strand breaks (dsbs) yield. After electrophoresis, comets were briefly incubated in an alkaline unwinding solution, transforming DNA breaks and alkali-labile sites into restricted single-stranded DNA (ssDNA) motifs. These motifs behave as target sites for hybridization with a whole genome probe, following the DNA breakage detection-fluorescence in situ hybridization (DBD-FISH) procedure. As DNA breakage increases with dose, more ssDNA is produced in the comet by the alkali and more DNA probe hybridizes, resulting in an increase in the mean fluorescence intensity. Since radiation-induced DNA single-strand breaks (ssbs) are far more frequent than dsbs, the mean fluorescence intensity of the DBD-FISH signal from the comet is related to the ssb level, whereas the surface area of the same comet signal is indicative of the dsb yield. Thus, both DNA break types may be simultaneously analyzed in the same cell. This was confirmed in a repair assay performing the DBD-FISH on neutral comets from a human cell line defective in the repair of dsbs. Otherwise, treatment with hydrogen peroxide, a main inducer of ssbs, increased the mean fluorescence intensity, but not the surface, of X-ray-exposed human leukocytes.

Comet Assay↗
PubMed2001

Evidence of abundant constitutive alkali-labile sites in human 5 bp classical satellite DNA loci by DBD-FISH.

Human blood leukocytes within an agarose matrix were deproteinized and exposed to an alkaline denaturation that generates single-stranded DNA (ssDNA) starting from the ends of spontaneous basal DNA breaks and alkali-labile sites. Since the amount of ssDNA produced within a specific sequence area may be detected by hybridization with a specific probe, we quantified this in situ in different satellite DNA loci (DBD-FISH: DNA Breakage Detection FISH). The DBD-FISH signal, corrected for the respective FISH signals in metaphase, was remarkably strong in the 5bp classical satellite DNA domains analyzed (D1Z1, D9Z3, DYZ1), intermediate in the classical satellite 1 DNA sequences, and low in the alphoid satellite regions (D1Z5, DXZ1, all centromeres). This result is evidence of a high density of constitutive alkali-labile sites, probably abasic sites, within the 5bp satellite DNA sequences in human blood leukocytes. The presence and relative abundance of alkali-labile sites could explain the high frequency of spontaneous breakage and rearrangements in pericentromeric heterochromatin of chromosomes 1, 9, and 16, but not in Yqh, when this chromatin is undercondensed through spontaneous or induced demethylation, i.e. ICF syndrome or 5-azacytidine treatment.

Centromere↗
PubMed2001

Sau3A in situ digestion of human chromosome 3 pericentrometric heterochromatin. I. Differential digestion of alpha-satellite and satellite 1 DNA sequences.

In situ digestion with the restriction endonuclease (RE) Sau3A (Sau3A REISD) uncovers a polymorphism for the pericentromeric heterochromatin of human chromosome 3, which can be positively stained (3+) or not (3-), and has proven useful to differentiate donor and recipient cells after sex-matched bone marrow transplantation and to analyze the so-called hemopoietic chimerism. The aim of the present investigation was to obtain insight into the molecular basis of such polymorphism to optimize its use for chimerism quantification using methodological approaches other than REISD. To this end, fluorescence in situ hybridization (FISH) assays using probes for the satellite DNA sequences that mainly constitute chromosome 3 pericentromeric heterochromatin (alpha-satellite and satellite 1 DNA) were performed on control and Sau3A-digested chromosomes. The results obtained suggest that chromosome 3 alpha-satellite DNA is digested in all individuals studied, irrespective of the karyotype obtained by Sau3A REISD (3++, 3+-, 3--), and thus it does not seem to be involved in the polymorphism uncovered by Sau3A on this chromosome. Satellite 1 DNA is not digested in any case, and shows a polymorphism for its domain size, which correlates with the polymorphism uncovered by Sau3A in such a way that 3+ chromosomes show a large domain (3L) and 3- chromosomes show a small domain (3S). It seems, therefore, that the cause of the polymorphism uncovered by Sau3A on the pericentromeric region of chromosome 3 is a difference in the size of the satellite 1 DNA domain. Small satellite 1 DNA domains fall under the resolution level of REISD technique and are identified as 3-.

Centromere↗
PubMed2001

Lymphocyte chromosomal aberrations and their complexity induced in vitro by plutonium-239 alpha-particles and detected by FISH.

G0 human lymphocytes were exposed in vitro to plutonium-239 alpha-particles, with doses ranging from 0 to 1.62 Gy, to provide a dose response curve and to compare complex rearrangements produced by high LET radiation with low LET data from previous work. Metaphase chromosomes 1 and 2 were painted using fluorescence in situ hybridization (FISH) whole chromosome probes. All unstable and stable aberrations involving the painted chromosomes were scored. The whole genome corrected alpha-coefficient for dicentrics was 0.244 +/- 0.023 and for total translocations 0.346 +/- 0.032, when considering simple and complex exchanges. The ratio of bicoloured total translocations to bicoloured dicentrics was 1.21 +/- 0.15 and the ratio of 2-way to 1-way translocations was 1.73 +/- 0.27 for apparently simple exchanges only. A correlation was noted between the distributions of dicentrics and translocations and this applied even when the complex rearrangements were removed. 20% of the observed rearrangements were complex and this observation was independent of dose. Qualitatively, following irradiation with alpha-particles the complex rearrangements observed were of a greater complexity than seen after X- or gamma-rays. Using the Savage and Simpson system to classify the complex rearrangements, the higher order complexes were found to be the most common type observed. However the insertion type increased while the 2F + 2G types decreased when complex rearrangements induced by alpha-particles were compared to those formed after X- or gamma-irradiation.

Alpha Particles↗
PubMed2000

DNA breakage detection-FISH (DBD-FISH) in human spermatozoa: technical variants evidence different structural features.

Non-irradiated and X-irradiated (80 Gy) human spermatozoa were processed for in situ DNA breakage detection-FISH (DBD-FISH) of the whole genome, following two alternative variations of the basic technique. In the first, cells were initially incubated in the alkaline unwinding solution for transformation of DNA breaks into single-stranded DNA (ssDNA) to be hybridized, followed by the lysing solutions for protein removal. In the second, incubation in the lysing solutions was carried out before the denaturation step. The first approach yielded two subpopulations. While most sperm nuclei were faintly labeled and had chromocenters, a small subpopulation was strongly and homogeneously labeled, due to extensive DNA breakage. X-ray exposure increased the surface and mean fluorescence intensity. Otherwise, when the denaturation step was performed after protein extraction, all sperm nuclei yielded strong and dispersed FISH signals. Protein removal allows access of the unwinding solution to the DNA, which has abundant alkali-labile sites, and thus gives rise to large areas of ssDNA that are labeled by FISH. X-ray exposure increased the dispersion of FISH signals but decreased their mean fluorescence intensity. A linear dose-response was generated using the second experimental variant, being 30 Gy the lowest dose for detecting induction of damage by X-rays in mature sperm chromatin. These results indicate that DBD-FISH is not only useful for in situ detection of DNA breakage but also for revealing structural features of chromatin.

DNA↗