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C de la Torre

Publications and source records attributed to C de la Torre.

At least 19 recordsLinked to original sources
PubMed2005

Ehlers-Danlos syndrome and periventricular nodular heterotopia in a Spanish family with a single FLNA mutation.

BACKGROUND: The Ehlers-Danlos syndrome (EDS) comprises a group of hereditary connective tissue disorders. Periventricular nodular heterotopia (PNH) is a human neuronal migration disorder characterised by seizures and conglomerates of neural cells around the lateral ventricles of the brain, caused by FLNA mutations. FLNA encodes filamin A, an actin binding protein involved in cytoskeletal organisation. The amino-terminal actin binding domain (ABD) of filamins contains two tandem calponin homology domains, CHD1 and CHD2. OBJECTIVE: To report clinical and genetic analyses in a Spanish family affected by a connective tissue disorder suggestive of EDS type III and PNH. METHODS: A clinical and molecular study was undertaken in the three affected women. Clinical histories, physical and neurological examinations, brain magnetic resonance imaging studies, and skin biopsies were done. Genetic analysis of the FLNA gene was undertaken by direct sequencing and restriction fragment length polymorphism analysis. RESULTS: Mutation analysis of the FLNA gene resulted in the identification of a novel mutation in exon 3 (c.383C-->T) segregating with the combination of both syndromes. This mutation results in a substitution of an alanine residue (A128V) in CHD1. CONCLUSIONS: The findings suggest that the Ala128Val mutation causes the dual EDS-PNH phenotype. This association constitutes a new variant within the EDS spectrum. This is the first description of a familial EDS-PNH association with a mutation in FLNA.

Amino Acid Substitution↗
PubMed2004

HSP90 and checkpoint-dependent lengthening of the G2 phase observed in plant cells under hypoxia and cold.

Proliferating cells of Allium cepa L. roots became adapted to hypoxia (5% oxygen) and cold (10 degrees C) by acquiring new steady-state kinetics of growth. The cell cycle time increased from the 17.6 h in control meristems up to 29.7 and 69.0 h under hypoxia and cold conditions, respectively. Acclimation of the proliferating cells was stress specific. No acclimation took place after 24 h of heat treatment (40 degrees C). Under cold treatment, all cycle phases enlarged uniformly. However, under hypoxia, while the G(1) and S cycle phases roughly doubled in their timing, the expected checkpoint-dependent lengthening of G(2) did not take place. This failure in lengthening G(2) in response to hypoxia correlated with a failure in the overinduction of a single peptide with a molecular mass of about 134 kDa which is among those recognised by an HSP90 antibody. Moreover, the presence of this large peptide of the HSP90 family proved to be a marker for cell proliferation. It was always absent from the contiguous differentiated cells of the root. Lastly, the mitochondrial chaperonin recognized by an HSP60 antibody in these roots not involved in photosynthesis was always higher in the proliferating than in the nonproliferating cells.

Cell Hypoxia↗
PubMed2004

Genome remodelling in three modern S. officinarumxS. spontaneum sugarcane cultivars.

This study provides evidence that nuclear and chromosome remodelling has taken place in sugarcane, a vegetative crop with a complex genome derived from interspecific hybridizations between Saccharum officinarum and S. spontaneum. Detailed knowledge on the chromosomal compositions of the three clones analysed was acquired. (1) All hybrid cultivars were found to be aneuploid, affecting both parental genomes (having chromosomes in addition to full genomes), with chromosome numbers from 2n=102-106 in My5514 and up to 2n=113-117 in C236-51. (2) Comparative in situ hybridization showed that about 16% of these chromosomes are inherited from S. spontaneum and less than 5% are recombinant or translocated chromosomes containing sequences of both S. officinarum and S. spontaneum. (3) Differences between the observed DNA contents (estimated by flow cytometry) and those expected from the number of chromosomes, allowed the introgression of additional S. spontaneum or S. officinarum DNA pieces into the B42231 and C236-51 cultivars to be estimated. (4) Size heterogeneity between S. officinarum homologous chromosomes carrying the 18S-5.8S-25S and 5S ribosomal genes (identified by FISH with pTa71 and pTa794, respectively) confirms remodelling occurred by chromosomal interchange events, at least in these homologous chromosomes. (5) Simultaneous visualization of nucleoli and NORs showed that all 18S-5.8S-25S loci were potentially functional in the three clones, independent of their origin and size.

Chromosome Mapping↗
PubMed2003

Effect of caffeine on in vivo processing of alkylated bases in proliferating plant cells.

DNA damage was induced by either 2 mM ethylmethanesulfonate or 1 Gy of gamma-irradiation in Allium cepa L. root meristems. The percentage of DNA that migrated towards the anode during microelectrophoresis after alkali denaturation (pH approximately 13.5) of the isolated nuclei (comet assay) reflects the amount of single strand breaks present in them. There was some DNA migration (12.8+/-2.4%) in untreated roots. This percentage doubled at the end of 1.5 h treatment with the mono-functional alkylating agent 2 mM ethylmethanesulfonate, and trebled after a single exposure to 1 Gy of gamma-rays. A proportion of the DNA migration caused by these two treatments was reversed (repaired) by a 2 h long period of in vivo recovery. However, when 5 mM caffeine was applied after removal of the alkylating agent, the amount of DNA migrating to the comet tail over the same 2 h period was almost double that at the onset of recovery. In both control and irradiated nuclei, caffeine also increased the initial level of DNA migration in the comet assay, but to a lesser extent. These results indicate that caffeine increases the DNA damage that accumulates during the processing of alkylated bases and, to a lesser extent, of the DNA bases damaged by gamma-irradiation. Thus, the potentiation effect of caffeine on induced chromosomal damage may not just be due to caffeine-induced cancellation of the G2 checkpoint, but also to a direct effect this methylxantine has on the processing of DNA damage.

Alkylation↗
PubMed2002

Inpatient dermatology: characteristics of patients and admissions in a Spanish hospital.

BACKGROUND: Inpatient dermatology has not been properly described in many countries. National differences might be important in the evaluation of its usefulness and the applicability of politics of health expenditure restrictions. OBJECTIVE: To describe inpatient activity and readmission rates in a dermatology department in Spain. STUDY DESIGN: Cross-sectional prospective study in a single hospital. SETTING: Secondary care hospital of the National Health Service in Pontevedra (Spain). METHODS: From May 1997 to December 2000, all discharge sheets (1048) were included in the study, codified and described. RESULTS: Surgery was the reason for admission in 37% of the inpatients. The most frequent diagnosis were: neoplasm (36%), infection (15%), psoriasis (10%), other (10%), dermatitis (6%) and drug reaction (5%). Readmission rates were 1.8% within 30 days, and 12.5% within 1 year. CONCLUSIONS: Inpatient dermatology is different in different countries. Compared with what has been described in the USA or UK, our data suggest an important surgical content of inpatient dermatology in Spain, not reported in those countries. Medical diagnoses also differ, consisting of more infections, and less psoriasis and dermatitis in our setting. Readmission rates are low when compared with previously published ones, a finding that supports a long-term benefit of hospitalization.

Adult↗
PubMed2001

Synchronous nuclear-envelope breakdown and anaphase onset in plant multinucleate cells.

Multinucleate plant cells with genetically balanced nuclei can be generated by inhibiting cytokinesis in sequential telophases. These cells can be used to relate the effect of changes in the distribution of nuclei in the cytoplasm to the control of the timing of cell cycle transitions. Which mitotic cell cycle events are sensitive to differences in the amount of cytoplasm surrounding each chromosomal complement has not been determined. To address this, we maximized the cell size by transiently inhibiting replication, while cell growth was not affected. The nuclei of 93% of the elongated cells reached prophase asynchronously compared to 46% of normal-sized multinucleate cells. The asynchronous prophases of normal-sized cells became synchronous at the time of nuclear-envelope breakdown, and the ensuing metaphase plate formation and anaphase onset and progression occurred synchronously. The elongated multinucleate cells were also very efficient in synchronizing the prophases at nuclear-envelope breakdown, in the prophase-to-prometaphase transition. However, 2.4% of these cells broke down the nuclear envelope asynchronously, though they became synchronous at the metaphase-to-anaphase transition. The kinetochore-microtubular cycle, responsible for coordinating the metaphase-to-anaphase transition and for the rate of sister segregation to opposite spindle poles during anaphase, remained strictly controlled and synchronous in the different mitoses of a single cell, independently of differences in the amount of cytoplasm surrounding each mitosis or its ploidy. Moreover, the degree of chromosome condensation varied considerably within the different mitotic spindles, being higher in the mitoses with the largest surrounding cytoplasm.

Allium↗
PubMed2001

Ataxia telangiectasia: G2 checkpoint and chromosomal damage in proliferating lymphocytes.

There is a checkpoint pathway in eukaryotic cells that depends on ATM (ataxia telangiectasia mutated) kinase which activates the processes leading to the repair of DNA damage and also lengthens the G(2) stage of the cell cycle. In cells from ataxia telangiectasia patients, due to their lack of active ATM kinase, an increase in chromosomal aberrations and a failure to induce G(2) lengthening could be expected. However, the basal G(2) timing in ataxia telangiectasia cells was longer than in controls and was further extended after X-ray irradiation (0.4 Gy), although to a lesser extent than in controls. Moreover, in control cells caffeine shortened G(2) and increased chromosomal damage 7-fold, while in ataxia telangiectasia cells caffeine only trebled aberration yield without shortening G(2). As caffeine is an inhibitor of ATM kinase, these results suggest the existence of some redundant ATM-independent checkpoint in G(2) of ataxia telangiectasia cells. The differential response to caffeine of ataxia telangiectasia and control lymphocytes may be explained by the presence of two different subpathways in the G(2) checkpoint: one regulating the processing and repair of damaged DNA and the other controlling G(2) timing. While in controls both subpathways may be mediated by ATM kinase, in ataxia telangiectasia cells caffeine-sensitive ATR kinase and the caffeine-insensitive DNA-PK kinases might be responsible for DNA repair and the G(2) delay subpathways, respectively. Confirmation of this model in ataxia telangiectasia cells with another cell type in which both subpathways are mediated by DNA-PK should define whether a metylxanthine such as caffeine may also have an additional direct inhibitory effect on DNA repair.

Ataxia Telangiectasia↗
PubMed2001

Dormancy and proliferation in Saccharum officinarumxS. spontaneum hybrids which differ in the number of the introgressed S. spontaneum chromosomes.

Proliferating cells remain transiently blocked at different cycle compartments until specific stressors are removed or until the cells become adapted to their presence. This paper investigates the efficiency of cycle blocks in three sugarcane hybrids with the full noble cane (Saccharum officinarum) genome (2n=8x=80) but differing in the number of introgressed S. spontaneum (2n=8x=64) chromosomes. The My5514, B42231 and C236-51 cultivars possess 20, 30 and 40 additional S. spontaneum chromosomes, respectively. Flow cytometry showed that over 90% of cells were accumulated with a 2C DNA content in their dormant primordia. The presence of S. spontaneum chromosomes decreased the low stringency of the 4C block. The greater the number of these chromosomes, the lower was the number of quiescent cells with a 4C DNA content (P<0.05). Shortly after stimulation of the primordia (85% relative humidity and 30 degrees C), i.e. in the 2 mm long roots, a negative correlation was found between the number of introgressed S. spontaneum chromosomes and the frequency of cells undergoing replication and mitosis. On the other hand, when roots were already proliferating under steady-state conditions (15 mm long roots) the more S. spontaneum chromosomes the cells possessed, the longer the relative time it took for all chromosomes to replicate and segregate, and the longer the relative time they spent in G(2), with the 4C DNA content. The presence of S. spontaneum chromosomes seems to be recognized by these proliferating cells as a stressor which preferentially activates checkpoint pathways operating at the second half of the cycle, but not at its onset.

Cell Cycle↗
PubMed2000

[Olive oil and inhibition of low density lipoprotein oxidation. Role of phenolic compounds].

BACKGROUND: To investigate the protective effect of several olive oils with different phenolic composition on low density lipoprotein susceptibility to oxidation. PATIENTS AND METHODS: Refined olive oil (phenolic content: 0 mg/l caffeic acid equivalents [CAE]), common olive oil (0.1 and 0.3 mg/l CAE), and virgin olive oil diluted with refined olive oil (0.1 y 0.3 mg/l CAE), were added to isolated low density lipoprotein. Conjugated dienes formation was monitored after copper-mediated low density lipoprotein oxidation. RESULTS: An increase in the lag time of conjugated dienes formation after copper-mediated low density lipoprotein oxidation was observed linked to olive oil phenolic content (p < 0.0001, ANOVA). Multiple regression analysis showed that phenolics were the most significant antioxidants with 0.1 mg/l--increase in phenolic concentration, adjusted for alpha-tocopherol and beta-carotene, was 72 minutes (95% confidence interval [CI] 64 to 80 min) for common olive oil, and 111 min (CI 95%: 100-123 min) for virgin olive oil. In common olive oil alpha-tocopherol levels were significatively associated with the increase in the lag time (p = 0.003), reaching in virgin olive oil a borderline significant (p = 0.084). CONCLUSIONS: Olive oil containing phenolics showed more antioxidant effect on low density lipoprotein oxidation than refined olive in relation to its phenolic content. The nature of the phenolic content influences the antioxidant capacity of an olive oil.

Antioxidants↗
PubMed2000

Protective effect of olive oil and its phenolic compounds against low density lipoprotein oxidation.

The protective effect of phenolic compounds from an olive oil extract, and of olive oils with (extra-virgin) and without (refined) phenolic components, on low density lipoprotein (LDL) oxidation was investigated. When added to isolated LDL, phenolics [0.025-0.3 mg/L caffeic acid equivalents (CAE)] increased the lag time of conjugated diene formation after copper-mediated LDL oxidation in a concentration-dependent manner. Concentrations of phenolics greater than 20 mg/L inhibited formation of thiobarbituric-acid reactive substances after AAPH-initiated LDL oxidation. LDL isolated from plasma after preincubation with phenolics (25-160 mg/L CAE) showed a concentration-dependent increase in the lag time of conjugated diene formation after copper-mediated LDL oxidation. Refined olive oil (0 mg/L CAE) and extra-virgin olive oil (0.1 and 0.3 mg/L CAE) added to isolated LDL caused an increase in the lag time of conjugated diene formation after copper-mediated LDL oxidation that was related to olive oil phenolic content. Multiple regression analysis showed that phenolics were significantly associated with the increase in lag time after adjustment for effects of other antioxidants; alpha-tocopherol also achieved a statistically significant effect. These results indicate that olive oil phenolic compounds protect LDL against peroxyl radical-dependent and metal-induced oxidation in vitro and could associate with LDL after their incubation with plasma. Both types of olive oil protect LDL from oxidation. Olive oil containing phenolics, however, shows more antioxidant effect on LDL oxidation than refined olive oil.

Chromatography, High Pressure Liquid↗
PubMed1999

Effect of vitamin E on chromosomal aberrations in lymphocytes from patients with Down's syndrome.

A possible protective effect of vitamin E (DL-alpha-tocopherol) on chromosomal damage was evaluated in lymphocytes from patients with Down's syndrome (DS) and from controls. This included the analysis of the basal and G2 chromosomal aberration frequencies in lymphocytes cultured with and without 100 microM vitamin E. The chromosomal damage in G2 was determined by scoring the number of chromosomal aberrations in lymphocyte cultures treated with 5 mM caffeine, 2 h before harvesting. Vitamin E treatment decreased the basal and G2 chromosomal aberrations both in control and DS lymphocytes. In DS cells, this protective effect, expressed as a decrease in the chromosomal damage, was greater (50%) than in controls (30%). These results suggest that the increment in basal and G2 aberrations yield in DS lymphocytes may be related to the increase in oxidative damage reported in these patients.

Caffeine↗
PubMed1999

Acquired cutaneous lymphangiectasia in a patient with cirrhotic ascites.

BACKGROUND: Lymphangiectasia results from acquired dilation of lymphatic vessels. Areas of skin affected by obstruction or destruction of lymphatic drainage are said to be prone to the development of lymphangiectasia. Cirrhosis is a cause of alterations of lymph flow. METHODS: Case report. RESULTS: We report a case of acquired, late-onset, lymphangiectasia associated with alcoholic hepatic cirrhosis. Lesions were scattered over the right, lower, anterior abdominal wall, a region that is drained by a common group of lymphatic vessels that were probably disordered. CONCLUSION: We think that this is the first reported case of lymphangiectasia associated with altered lymph flow in cirrhosis and ascites.

Adult↗
PubMed1998

In vivo response of mouse liver to gamma-radiation assessed by the comet assay.

The alkaline comet assay was used to measure DNA damage induced in liver cells of mice irradiated with gamma-radiation, as well as the repair competency of these cells. A simplified procedure for the isolation of nuclei from cells in solid tissues was developed. This simplified method allows nuclei to be processed into lysis only 5 min after briefly chilling the tissue to depress any enzymatic activity. The nuclei were spontaneously released by a sharp cut of the tissue and exposure of the cut to a drop of 50 mM sodium-phosphate buffer at pH 7.2, immediately before adding the low melting agarose. Thus, the procedure minimizes time-dependent modification of the endogenous level of damage by reducing additional strand breaks or repair produced during processing. The induction of DNA damage by gamma-radiation behaved as a one-hit event in the liver cells, as there was a positive linear correlation between the radiation dose and the fraction of DNA migrated into the comet tails. The level of DNA damage produced by gamma-radiation was highly significant at doses of 0.5 and 1 Gy. Based on the mean extent of DNA migration, the level of damage was not reduced following only one hour of repair time however, after two hours, there was a significant reduction in DNA migration. To increase the resolution of the statistical analysis, the nuclei of each sample were distributed in five types of comets, according to the percentage of DNA in the tail. To compare the frequency distributions of these types of comets between different experimental situations, a Pearson chi-square statistical analysis was applied. It was found, by this analysis, that the DNA repair which occurred 1 h after 1 Gy of gamma-irradiation is significant and that, after 2 h, more DNA repair occurs, but a significant residual damage still persists when comparing this sample with the control.

Animals↗