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C Lozano

Publications and source records attributed to C Lozano.

At least 19 recordsLinked to original sources
PubMed2005

Conjugation of catechins with cysteine generates antioxidant compounds with enhanced neuroprotective activity.

Antioxidant compounds derived from the conjugation of (-)-epicatechin and (-)-epicatechin 3-O-gallate with cysteine and cysteine derivatives protected HT-22 nerve cells (EC50 between 36 and 65 microM) from death triggered by glutamate while underivatized (-)-epicatechin was almost inactive (EC50=610 microM). Differences in free radical scavenging capacity (DPPH assay) could not account for the improvement in neuroprotective activity upon derivatization of (-)-epicatechin with thiols. Moreover, while the gallate-containing compounds are more efficient radical scavengers than their non-galloylated counterparts, they are only equally or less potent as neuroprotective agents. Although all of the conjugates were able to scavenge mitochondrially generated reactive oxygen species (ROS) inside the cells, the majority of their neuroprotective activity appeared to be dependent upon their ability to maintain glutathione levels. These results suggest that a mechanism other than ROS scavenging is involved in the neuroprotective action exerted by the epicatechin conjugates.

Animals↗
PubMed2005

Prevalence and correlates of depression in treatment-seeking women with vulvodynia.

This study aimed to examine rates and correlates of depression in a treatment-seeking sample of women with vulvodynia. A total of 53 women were independently diagnosed with vulvodynia and assessed with state-of-the-art measures of major depressive disorder (MDD) and depressive symptom severity as well as psychometrically established measures of pain severity, general functioning, sexual function and quality of life. Current and lifetime prevalence rates for MDD were 17% (n = 9) and 45% (n = 24), respectively. Women with current MDD reported significantly greater pain severity, and worse functioning and quality of life than women without current MDD. Among those with lifetime MDD, the majority (62.5%) reported that their first depressive episode occurred before the onset of vulvodynia. Rates of current MDD appeared to be lower than rates of MDD among other samples of treatment seeking chronic pain patients. In summary, co-morbid MDD is related to greater pain severity and worse functioning among women with vulvodynia.

Adolescent↗
PubMed2004

Percutaneous absorption of flavan-3-ol conjugates from plant procyanidins.

Catechins (flavanols) are strong antioxidants, free radical scavengers and inhibitors of lipid peroxidation. New bio-based antioxidant compounds obtained by depolymerization of plant polymeric flavanols (procyanidins) in the presence of cysteine or cysteamine, as well as their underivatized counterpart, (-)-epicatechin, were evaluated in terms of their percutaneous absorption profiles taking into account their free radical scavenging efficiency. The evaluation of the percutaneous absorption of flavanols was carried out by an in vitro methodology using both pig and human skin. A good correlation was obtained using both skins in the evaluation of the skin absorption profiles. It can be deduced that 4beta-(S-cysteinyl)epicatechin (Cys-Ec) has a tendency to be located mainly in the outermost layers of the skin, whereas 4beta-(2-aminoethylthio)epicatechin (Cya-Ec) has a pronounced percutaneous absorption capacity. Their antioxidant properties and their skin penetration profiles support their potential cosmetic or pharmacological applications.

Animals↗
PubMed2003

Cardiopulmonary transplantation: experience of a lung transplant group.

Cardiopulmonary transplantation (CPT) is indicated for patients eligible for heart transplantation (HT) or lung transplantation (LT) who have severe concomitant lung or heart disease. Only 2 groups perform CPT in Spain. We report our experience with 18 CPTs representing 8.2% and 5% compared with LT (220) and HT (362), respectively, from February 13, 1990 to October 15, 2002. The mean time on a waiting list was 138 days. The current number of surviving patients is 7 (39%), with a mean follow-up of 602 days (range, 3 to 4627 days). They all remain asymptomatic with normal respiratory function in 4 patients. No cardiac graft rejection has been detected. Two patients experienced sustained gastroparesis during the first year with spontaneous resolution. Death occurred within the first 3 months in 9 patients. These outcomes contrast with the early mortality associated with LT and HT in our series, namely 10.6% and 11%, respectively. The different causes of death were as follows: sepsis and multiorgan failure in 5 patients, hemorrhagic shock in 3 patients, and suture dehiscence and fungal aortic perforation in 1 patient. Late mortalities were recorded in 2 cases. Overall patient survival in our series is lower than that reported by the International Registry (IR), with an early mortality rate of 50% (30% IR). Nevertheless, our survival rate at 10 years after transplantation is 30% (26% IR). We conclude that CPT should be considered despite the greater early morbidity and mortality.

Adolescent↗
PubMed2003

[Impact of the protocol of ABO group and irregular antibodies on the transfusional index].

OBJECTIVES: The ABO group/irregular red cell antibodies (G/A) protocol is a scheme for reducing the number of unnecessary crossmatch tests in selected patients scheduled for surgery. Reduction would lower expenses and risks related to the overuse of such tests. Studying transfusion rates allows us to predict which patients are candidates for application of the protocol. The present study evaluated the impact of the G/A protocol on transfusion rate. PATIENTS AND METHODS: A retrospective analysis of pre-transfusion testing of patients in our hospital in 1996, before application of the G/A protocol, and in 2001, after four years of experience with the scheme. RESULTS: The G/A protocol was followed with 194 patients in 2001. The surgical transfusion rate decreased by 27.8% over the rate for 1996 (1.84 vs. 2.55). The outdating of blood units in 2001 decreased by 42.4% (65 units outdated vs. 113). Only one patient subject to the protocol had to be transfused. CONCLUSION: The transfusion rate can be significantly reduced by applying the G/A protocol with selected patients, with no loss of transfusion safety.

ABO Blood-Group System↗
PubMed2002

Cation-exchange micropreparative separation of galloylated and non-galloylated sulphur conjugated catechins.

Catechin conjugates bearing an amino function can be separated from underivatized monomers by cation-exchange chromatography. Here, chromatographic conditions for the separation of epicatechin gallate-containing conjugates from the non-galloylated conjugates at micropreparative scale are described. The separation was achieved by exploiting either the hydrophobic or hydrophilic interactions of the conjugates with the core polymer. The retention was modulated by changing the amount of organic co-solvents (MeOH, EtOH, CH3CH, THF) in the elution buffers. The best resolution compatible with small peak widths was obtained at 20-30% EtOH. The experiments were reproducible.

Catechin↗
PubMed2002

Quantitative ultrasound calcaneus measurements: normative data and precision in the spanish population.

Quantitative ultrasound (QUS) assessment at the calcaneus has been found to be a safe and reliable method for evaluating skeletal status. In this study we have determined the normative QUS data in the Spanish population for the Sahara Clinical Sonometer (Hologic). Broadband ultrasound attenuation (BUA), speed of sound (SOS), quantitative ultrasound index (QUI) and estimated bone mineral density (BMD) were determined. We also studied the precision in vivo and in vitro. The short-term in vivo precision (CV) was 4.88% for BUA, 0.36% for SOS, 3.45% for QUI and 4.15% for BMD, while in vitro precision was 0.40% for SOS and 2.67% for BUA. Our results are comparable to reference population data previously published in other countries and may serve as reference normative data for both genders in Spain.

Adolescent↗
PubMed2002

Cysteinyl-flavan-3-ol conjugates from grape procyanidins. Antioxidant and antiproliferative properties.

New bio-based antioxidant compounds have been obtained by depolymerisation of grape polymeric flavanols in the presence of cysteine. Their preparation and purification, as well as their antiradical/antioxidant and antiproliferative properties are reported. 4beta-(S-cysteinyl)epicatechin 5, 4beta-(S-cysteinyl)catechin 6 and 4beta-(S-cysteinyl)epicatechin 3-O-gallate 7 were efficiently purified from the crude depolymerised mixture by cation-exchange chromatography and preparative reversed-phase chromatography. The new compounds were more efficient than the underivatised (-)-epicatechin 1 as scavengers of the 1,1-diphenyl-2-picrylhydrazyl free radical (DPPH) and weak growth inhibitors of human colon carcinoma HT29 cells. The order of antiradical and antiproliferative efficiency was 7 >5 approximately 6 >1, the same for both assays.

Antineoplastic Agents↗
PubMed2000

Influence of atrial fibrillation on the morbido-mortality of patients on hemodialysis.

BACKGROUND: The consequences of atrial fibrillation (AF) on morbido-mortality of patients on hemodialysis have not been fully explored. The objective of this study was to determine the prevalence of AF in patients on hemodialysis and to evaluate its influence on the development of thromboembolic phenomena (TEP). METHODS: The incidence of AF in 190 patients in our hemodialysis program was assessed, and the patients were followed up for 1 year. Pertinent demographic and biochemical parameters were entered into univariate and multivariate statistical analyses to evaluate associations with overall mortality and TEP such as cerebrovascular accident, transitory ischemic accident, or peripheral embolism. RESULTS: In 13.6% of patients, AF was found; 9.4% of these were of the permanent type. In the multivariate analysis, only increased age was associated with a higher probability of having arrhythmia (odds ratio, 1.10; 95% confidence interval, 1.03-1.17; P =.003). During follow-up, 23% of the patients with AF died compared with 6% of those in sinus rhythm (P <.05), although AF did not appear to be an independent predictive factor for death. Thirty-five percent of the patients with AF and 4% with sinus rhythm had TEP (P <.01). In the multivariate analysis, AF was identified as the only independent predictor for TEP (odds ratio, 8; 95% CI, 2.3-27; P =.0008). CONCLUSIONS: AF is a frequent arrhythmia in patients on hemodialysis, and approximately 1 in 3 hemodialysis patients with AF had thromboembolic complications within 1 year of follow-up. These findings suggest that the consensus contraindication of prophylactic anticoagulation therapy for this group of patients may need to be redefined.

Adult↗
PubMed1999

Comparison of chromatin remodeling and transcriptional activation of the mouse mammary tumor virus promoter by the androgen and glucocorticoid receptor.

We examined the interaction between the androgen (AR) and glucocorticoid receptor (GR) at the transcriptional level using mouse fibroblast cell lines harboring an integrated mouse mammary tumor virus (MMTV) promoter. We found that the AR, after induction with dihydrotestosterone (DHT), caused a progressive increase in MMTV-CAT reporter activity over 72 h which was correlated to an increase in chromatin remodeling of the MMTV promoter in the vicinity of the hormone response element (HRE). In contrast, stimulation of the GR by the synthetic glucocorticoid dexamethasone (Dex) caused a transient increase in MMTV transcriptional activity which returned to basal levels after 72 h. These changes were correlated to a transient increase in chromatin remodeling in the region of the HRE. Neither cotreatment nor pretreatment with Dex affected the DHT response. In fact, there was a more than additive effect of the two hormones on transcription at early time points. This suggests that the inability of GR to remodel chromatin, after 24 h of hormone treatment, is most likely related to changes in the GR itself and not the chromatin remodeling process. Consistent with this, nuclear GR levels dropped by greater than 50% after Dex treatment whereas the AR was induced fourfold after 24 h of DHT treatment. We conclude that a promoter with an ordered chromatin structure can still respond to androgens even after its glucocorticoid responsiveness is lost. This may be one mechanism cells utilize to establish target gene specificity for nuclear receptors that recognize identical DNA sequences.

Animals↗
PubMed1999

[Application of selection criteria in sequential double lung transplantation].

Since the first sequential double lung transplant was performed in 1986, such procedures have been increasing in number and the criteria used as indications for this type of surgery have broadened. Our aim was to reflect on the application of selection criteria and to describe the anesthetic and surgical techniques and postoperative follow-up of 72 patients who underwent this type of transplant surgery between March 1993 and December 1998. Actuarial survival five years after surgery was 74.4%. Among patients requiring transplantation after septic disease, actuarial survival was 90.8% for cystic fibrosis and 88.2% for bronchiectasis. Of the preoperative risk factors analyzed (prior surgery, pachypleuritis, multiresistant germs, poor nutrition, mechanical ventilation and corticoid therapy), only prior treatment with high doses of corticoids proved significant. Eleven patients have been diagnosed of bronchiolitis obliterans, four have died and only two continue to experience difficulties in daily living. The high survival rate and the restriction-free life after recovery lead us to consider sequential double lung transplantation to be the treatment of choice for all pulmonary diseases.

Adult↗
PubMed1999

Ionizing radiation stimulates octamer factor DNA binding activity in human carcinoma cells.

In mammalian cells, the octamer motif (ATGCAAAT) binding proteins, Oct-1 and Oct-2, play an important role in the transcriptional transactivation of several ubiquitously expressed genes as well as cell-specifically expressed genes. To date, a role of the octamer binding proteins in damage-stimulated response is not known. In this report, we demonstrate that DNA-binding activity of Oct-1, as demonstrated by the electrophoretic mobility shift assay, is significantly induced in a dose-dependent manner upon treatment of human head and neck squamous carcinoma cells (PCI-04A) with ionizing radiation (5 Gy: 5-fold; 15 Gy: 11-fold). By comparison, activities of other transcription factors were modestly increased (15 Gy: AP-1, 2.5-fold; NF-kappaB, 2.6-fold; SP-1, 5-fold). Radiation stimulation of Oct-1 activity was also noted in two other human cancer cell lines, albeit to a lesser extent (MDA-MB231 breast carcinoma cells and PC-3 prostate carcinoma cells (5 Gy: approximately 2-fold). These data represent the first report of the activation of an octamer factor DNA binding activity in response to environmental cues and suggest a novel role of Oct-1 in the radiation signaling cascade in these cancer cells.

Carcinoma, Squamous Cell↗
PubMed1998

Detection of Leishmania (Viannia) braziliensis complex in wild mammals from Colombian coffee plantations by PCR and DNA hybridization.

The small mammal fauna of coffee plantations in SW Colombia was surveyed to determine which of the species present were infected with parasites of the Leishmania (Viannia) braziliensis complex and might therefore act as reservoirs of human cutaneous leishmaniasis. Fifty animals of seven different species were captured. Tissue samples were taken from the ears of specimens from each of the seven species. Thirty three samples were analysed by polymerase chain reaction (PCR) using oligonucleotide primers directed against conserved regions of L. (V) braziliensis complex kinetoplast DNA. Three of the samples (two from mouse opossums Micoureus demerarae, and one from a pygmy rice at Microryzomys minutus) gave positive results based on PCR analysis. When the samples were subjected to DNA hybridization (dot blot) analysis using the B18 (L. (V.) braziliensis complex-specific) probe, a total of ten specimens belonging to six species (the opossums M. demerarae and Didelphis marsupilalis, the rodents Melanomys caliginosus, Mi. minutus and Rattus rattus, and a rabbit Sylvilagus brasiliensis) gave positive results, indicating that all these animals had flies of species occurring in the same habitat by allowing them to feed on infected animals.

Animals↗
PubMed1998

[Postoperative management following single-stage laryngotracheoplasty in acquired subglottic stenosis in children].

Acquired laryngotracheal stenosis (ALTS) in children is a more and more common disease, following the widespread adoption of prolonged endotracheal intubation for respiratory support, specially among newborn and premature infants with respiratory distress syndrome. Several treatment procedures have been described in order to solve this problem; some authors have recently reported encouraging results with single-stage laryngotracheoplasty, making open reconstruction with airway division, cartilage grafts when appropriate, and closure of the tracheotomy tract at the same operation, followed by a short period of endotracheal intubation, avoiding the need for prolonged laryngeal stenting with its associated risks of granulation tissue formation, restenosis and airway obstruction, and with no need of new surgical procedures. Two patients of 9 and 16 months of age underwent successfully the surgical technique described above, with no need of laryngeal stent; postoperative management required several issues in order to prevent an accidental extubation during the time of scarring of the laryngotracheoplasty. No complications occurred. Follow-up at 6 and 12 months after operation was normal, both ventilation and voice quality.

Female↗
PubMed1998

[Infectious endocarditis caused by Leuconostoc mesenteroides].

BACKGROUND: Leuconostoc spp. are gram-positive coccobacilli, catalase and oxidase negative, vancomycin resistant, with a not clearly defined role in human infectious. Cases of infection have been reported previously but it has not been described confirmed infective endocarditis due to Leuconostoc mesenteroides. METHODS: We describe a case of prosthetic valve endocarditis in a 72-years-old woman with a long previous history of cardiac disease but without other immunological disorders. She developed a heart failure because of prosthetic aortic valve dysfunction. CONCLUSIONS: Leuconostoc mesenteroides should be considered as a potential cause of infective endocarditis and listed in the group of vancomycin-resistant microorganism.

Aged↗
PubMed1997

[Quantification of lamellar bodies in amniotic fluid: a method for the evaluation of fetal pulmonary maturity].

It was tried to know the counting up of lamellar bodies in amniotic fluid, as a test of fetal pulmonary maturity, comparing it with neonatal evolution. 31 samples of amniotic fluid of different ages of gestation, were obtained, lamellar bodies were quantified with a standard equipment of hematic counting, and comparing with neonatal evolution, sensitivity, specificity, positive predictive value, and negative predictive value are established. The established concentration of 30,000/l by comparison with Lecitine/Esfingomieline and with Fosfatidilglycerol was used. From 29 patients with counts greater than 30,000, none presented Respiratory Difficulty syndrome (SDR); and from two patients with lower counts, one presented SDR and one had normal neonatal evolution. Sensitivity was 96%; specificity was 100%; predictive positive value, 50%; and negative predictive value was 100%. Because of this, the test is so useful in practice. Its statistical values, its minimal cost; easiness to do, and equipment availability, justify this test as a first election.

Amniotic Fluid↗
PubMed1995

[Symptomatic hemobilia following hepatic biopsy. Value of ultrasonography in the diagnosis and control of this complication].

Hemobilia is the term which describes the presence of blood in the biliary tract. We describe a case of symptomatic hemobilia after percutaneous liver biopsy which resolved spontaneously. We review the physiopathology of this complication and we highlight the role of abdominal ultrasonography not only in the diagnosis but also in the follow-up of hemobilia. In our case, abdominal ultrasonography was able to identify the probable point of bleeding.

Biopsy↗