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F Pomar

Publications and source records attributed to F Pomar.

14 recordsLinked to original sources
PubMed2005

Varietal differences among the anthocyanin profiles of 50 red table grape cultivars studied by high performance liquid chromatography.

In order to develop a method that allows to distinguish between grape cultivars, the anthocyanin profiles of 50 accessions from the "Misión Biológica de Galicia" germplasm collection were studied by high performance liquid chromatography (HPLC). Nineteen anthocyanins were totally or partly identified and significant quantitative differences between the studied anthocyanin markers were found. With this method all 50 cultivars examinated could be easily distinguished from each other. In addition, the HPLC fingerprints and the relative-area anthocyanins plot for every cultivar has been elaborated and stored in a database. To test the validity of this method, several unknown samples have been analysed comparing their anthocyanin profile with the fingerprint database, and we may conclude that this has been proved to be of great value for grape cultivar recognition.

Anthocyanins↗
PubMed2002

O-4-Linked coniferyl and sinapyl aldehydes in lignifying cell walls are the main targets of the Wiesner (phloroglucinol-HCl) reaction.

The nature and specificity of the Wiesner test (phloroglucinol-HCl reagent) for the aromatic aldehyde fraction contained in lignins is studied. Phloroglucinol reacted in ethanol-hydrochloric acid with coniferyl aldehyde, sinapyl aldehyde, vanillin, and syringaldehyde to yield either pink pigments (in the case of hydroxycinnamyl aldehydes) or red-brown pigments (in the case of hydroxybenzaldehydes). However, coniferyl alcohol, sinapyl alcohol, and highly condensed dehydrogenation polymers derived from these cinnamyl alcohols and aldehydes did not react with phloroglucinol in ethanol-hydrochloric acid. The differences in the reactivity of phloroglucinol with hydroxycinnamyl aldehydes and their dehydrogenation polymers may be explained by the fact that, in the latter, the unsubstituted (alpha,beta-unsaturated) cinnamaldehyde functional group, which is responsible for the dye reaction, is lost due to lateral chain cross-linking reactions involving the beta carbon. Fourier transform infrared spectroscopy and thioacidolysis analyses of phloroglucinol-positive lignifying plant cell walls belonging to the plant species Zinnia elegans L., Capsicum annuumvar. annuum, Populus albaL., and Pinus halepensisL. demonstrated the presence of 4- O-linked hydroxycinnamyl aldehyde end groups and 4- O-linked 4-hydroxy-3-methoxy-benzaldehyde (vanillin) end groups in lignins. However, given the relatively low abundance of 4- O-linked vanillin in lignifying cell walls and the low extinction coefficient of its red-brown phloroglucinol adduct, it is unlikely that vanillin contributes to a great extent to the phloroglucinol-positive stain reaction. These results suggest that the phloroglucinol-HCl pink stain of lignifying xylem cell walls actually reveals the 4- O-linked hydroxycinnamyl aldehyde structures contained in lignins. Histochemical studies showed that these aldehyde structures are assembled, as in the case of coniferyl aldehyde, during the early stages of xylem cell wall lignification.

Arachidonic Acids↗
PubMed2001

Oxidation of cinnamyl alcohols and aldehydes by a basic peroxidase from lignifying Zinnia elegans hypocotyls.

The xylem of 26-day old Zinnia elegans hypocotyls synthesizes lignins derived from coniferyl alcohol and sinapyl alcohol with a G/S ratio of 43/57 in the aryl-glycerol-beta-aryl ether core, as revealed by thioacidolysis. Thioacidolysis of Z. elegans lignins also reveals the presence of coniferyl aldehyde end groups linked by beta-0-4 bonds. Both coniferyl and sinapyl alcohols, as well as coniferyl and sinapyl aldehyde, are substrates of a xylem cell wall-located strongly basic peroxidase, which is capable of oxidizing them in the absence and in the presence of hydrogen peroxide. This peroxidase shows a particular affinity for cinnamyl aldehydes with kappa(M) values in the mu(M) range, and some specificity for syringyl-type phenols. The affinity of this strongly basic peroxidase for cinnamyl alcohols and aldehydes is similar to that shown by the preceding enzymes in the lignin biosynthetic pathway (microsomal 5-hydroxylases and cinnamyl alcohol dehydrogenase), which also use cinnamyl alcohols and aldehydes as substrates, indicating that the one-way highway of construction of the lignin macromolecule has no metabolic "potholes" in which the lignin building blocks might accumulate. This fact suggests a high degree of metabolic plasticity for this basic peroxidase, which has been widely conserved during the evolution of vascular plants, making it one of the driving forces in the evolution of plant lignin heterogeneity.

Aldehydes↗
PubMed2000

Fruit development in Capsicum annuum: changes in capsaicin, lignin, free phenolics, and peroxidase patterns.

Pepper fruits, of Capsicum annuum cv. Padron, undergo changes in content of capsaicinoids, lignin, and free phenolics during the maturation process. Although capsaicinoids increase with development, the maximal levels of free phenolics and lignin are observed during the early stages of development. A decrease of peroxidase activity was observed during maturation, and this was related with a decrease in other physiological parameters studied, namely chlorophylls and pH. Subcellular fractionation studies reveal that most peroxidase activity is localized in the soluble fraction throughout development. The changes in the peroxidase activity were accompanied by changes in the different isoenzymes. Acidic isoenzymes increased whereas the basic isoenzymes decreased over the same period, and the changes in these isoenzymes were related with capsaicin metabolism.

Capsaicin↗
PubMed1999

Gastric antisecretory and antiulcer activities of an ethanolic extract of Bidens pilosa L. var. radiata Schult. Bip.

Bidens pilosa var. radiata Schult. Bip. is used in folk medicine to treat stomach disorders including peptic ulcers. The ethanolic extract (0.5-2 g/kg) decreased the gastric juice volume, acid secretion, as well as pepsin secretion in pylorus ligated rats. B. pilosa extract showed antiulcer activity against indomethacin-induced gastric lesions. The extract effectively inhibited gastric haemorrhagic lesions induced by ethanol, and with an effective dose of 2 g/kg being more potent than sucralfate (400 mg/kg). In contrast, ranitidine (50 mg/kg) failed to reduce these lesions. These results indicate that B. pilosa ethanolic extract exerts a cytoprotective effect in addition to its gastric antisecretory activity that could be due, partly at least, to the presence of flavonoids of which quercetin was identified by HPLC.

Animals↗
PubMed1999

Stenting in a patient with a single coronary artery and myocardial infarction.

The single coronary artery is an uncommon congenital defect. We report on a patient admitted to our hospital with an acute myocardial infarction and a single coronary artery arising from the left sinus of Valsalva who was treated with coronary angioplasty and stent implantation. We have not found an identical report of stenting in such an anomaly in the medical literature.

Adult↗
PubMed1997

[Differential characteristics and survival of women with acute myocardial infarction. Registry of Acute Myocardial Infarctions of the City of Valencia (RICVAL). Researchers of the RICVAL].

INTRODUCTION AND OBJECTIVES: The prevalence of women who are admitted to the hospital after acute myocardial infarction is lower to that of men and their prognosis is worse. The reason for these differences is unclear. We studied the demographic and historical variables, the evolution, treatment and early survival in 269 women included in the Register of Acute Myocardial Infarctions of the City of Valencia (RICVAL) and compared them with the 855 men included in the same Register. PATIENTS AND METHODS: Register of patients admitted into a Coronary Care Unit in the City of Valencia since December, 1st, 1993 until November 30th, 1994. RESULTS: 23.9% of the patients were women with a mean age of 71.9 +/- 9 years; 46.8% of them were diabetics, 55.4% hypertensives, and 6.7% smokers. The women arrived for treatment later than men and 34.9% of them were thrombolised. The incidence in women of severe heart failure (Killip III and IV) was 40.1% and the mortality 29.7%. In women with thrombolytic treatment the mortality was 29.8%. In the logistic regression model performed, female sex predicted a higher mortality rate (odds ratio [OR] = 1.30; confidence interval [CI], 1.05-1.61). CONCLUSIONS: Early mortality in women after acute myocardial infarction is higher than in men in the RICVAL Register. The longer delay in initiating medical care and thrombolysis might be the cause for the higher proportion of heart failure among women and explain their worse prognosis after an acute myocardial infarction compared to men.

Aged↗
PubMed1995

Functional and ultrastructural alterations of canine myocardium subjected to very brief coronary occlusions.

The effects of very brief and recurrent coronary occlusions on myocardial regional shortening and its ultrastructure have been analysed. Ultrasonic crystals were implanted in the left ventricular subendocardium of 23 anaesthetized dogs with the thorax open, to measure the shortening fractions of an ischaemic and a control segment. Twenty 2 min total occlusions were provoked in the left anterior descending coronary artery, with 3 min recovery intervals (reperfusion) between occlusions. The shortening fraction decreased progressively with each occlusion, reaching a value 18.9% lower than the basal after the last ischaemic episode (P < 0.05); 32.3% after 4 h of reperfusion (P < 0.01), and 28.6% after 24 h (P < 0.01). Qualitative and quantitative ultrastructural analysis showed an increase in the mitochondrial volume of the ischaemic tissue (158% vs control, P < 0.001) with significant damage to the cell components (7.7-fold increases vs control mitochondria). These results show that when the myocardium is subjected to very brief and repeated coronary occlusions, there is progressive deterioration of systolic function with structural alterations, mainly at the mitochondrial level. These modifications are still observable 24 h after the end of ischaemic stimulation and could be the cause of transitory and/or chronic systolic dysfunctions in the absence of previous heart attack.

Animals↗
PubMed1990

[Experience with dual-chamber pacemakers at the Valencia General Hospital].

We report our experience with dual chamber pacemakers in 70 patients (mean age 64.5), of whom 42 had AV block and 28 sick sinus syndrome, nine of them associated with AV block. Other cardiac disease coexistent with the conduction disturbance was present in 57% of the patients. Follow-up was conducted after implantation at first, 3rd, 6th month, and thereafter each 6 months. Mean follow-up was 20 +/- 14.3 months (2-72); of the 70 patients, 88% and 73% were followed at least for 6 and 12 months, respectively. Six patients (five had AV block) died 17 months on average after implantation. All patients but one had concomitant cardiac disease. Eleven patients (15.6%) presented complications, being all of them related to atrial channel: reprogramming to VVI in five (7%), mainly due to chronic atrial fibrillation (4 patients), whereas in the other one was secondary to loss of pacing and sensing functions; acute dislocation corrected with reoperation in 3 patients (4.3%); temporary loss of atrial sensing in 2 patients, and chronic in the last one, with change to DVI mode. Overall, considering deaths and changes to VVI mode, 15.6% of patients were not be able to maintain dual chamber pacing. In conclusion, our results show: 1) low rate of major complications; 2) good outcome of patients suffering from sick sinus syndrome; 3) the development of chronic atrial fibrillation was the main limitation of DDD pacing system.

Adult↗
PubMed1990

[Acute hepatic lesion caused by Giardia lamblia].

A study was made of 20 rats infested by Giardia muris in which a histologic study was made of the liver, as well as of 25 patients with giardiasis and elevated alanine-aminotransferase levels. Patients with positive A or B hepatitis markers, cholelithiasis or history of drug or alcohol use were excluded. Tests of liver function and liver biopsy were performed and antiparasite therapy was given during three months of follow-up, after which the liver biopsy was repeated. Humoral alterations were compared to those of 30 patients with acute viral hepatitis (15 type A and 15 type B) over the same periods of time. In 20% of the rats, nonspecific liver lesions were found. In the patients liver enzymes and the thymol test normalized a month after treatment and serum bile acids became normal in the third month. The liver biopsy demonstrated hepatic damage in 94% of the patients (in 20 cases cell lesions and in 12 cases inflammatory lesions) which regressed in the third month, the follow-up biopsy being normal after eradication of the parasite was confirmed. The comparative study with viral hepatitis showed highly significant differences in all the variables studied during the follow-up stage. Emphasis is placed on the importance of this lesion and its differential diagnosis to prevent its progression to chronic liver disease.

Acute Disease↗
PubMedDate not supplied

[Anomalous origin of the left coronary artery from the pulmonary artery in adults].

A 24 year old male with anomalous origin of the left coronary artery from the pulmonary artery was surgically treated with aortocoronary bypass with saphenous vein graft. The clinical signs and pathophysiology of this cardiopathy are reviewed, with emphasis on the great importance of collateral circulation in its prognosis.

Adult↗