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Biomedical subjects

A Garrido

Publications and source records attributed to A Garrido.

At least 37 records · Page 2Linked to original sources
PubMed2000

Protective effects of boldine against free radical-induced erythrocyte lysis.

Boldine, an aporphine alkaloid extracted from the leaves and bark of boldo (Peumus boldus Mol.), has been shown to exhibit strong free-radical scavenger and antioxidant properties. Here, we report the in vitro ability of boldine to protect intact red cells against the haemolytic damage induced by the free radical initiator 2, 2'-azobis-(2-amidinopropane) (AAPH). Boldine concentration-dependently prevented the AAPH-induced leakage of haemoglobin into the extracellular medium. Substantial and similar cyto-protective effects of boldine were observed whether the antioxidant was added 1 h prior to, or simultaneously with, the azo-compound. The delayed addition of boldine, by 1 h relative to AAPH, diminished but did not abolish its cytoprotective effect. However, negligible effects of boldine were observed after its addition to erythrocytes previously incubated with AAPH for 2 h. The data presented demonstrate that, in addition to its well-established antioxidant effects, boldine also displays time-dependently strong cytoprotective properties against chemically induced haemolytic damage.

Animals↗
PubMed2000

High frequency of altered HLA class I phenotypes in laryngeal carcinomas.

The exact frequency of HLA class I losses in human tumors is unknown. We have previously shown that primary breast and colorectal carcinomas frequently lose HLA class I molecules (88% and 73%, respectively). Now we report that this phenomenon is also a frequent event in laryngeal carcinomas. Of a total of 76 laryngeal carcinomas analyzed, 66% of the tumors showed an alteration in HLA class I phenotype. These altered HLA phenotypes were classified as total HLA loss (10.52%) (phenotype I); HLA-A locus-specific loss (13.15%) (phenotype IIIa); HLA-B locus-specific loss (10.52%) (phenotype IIIb); HLA allelic loss (27.63%) (phenotype IV); and HLA-A and B locus loss (3.9%). Comparison of histopathological parameters with HLA expression showed that poorly differentiated tumors had the lowest levels of HLA class I expression (p < 0.05).

Antibodies, Monoclonal↗
PubMed2000

Effects of supplementation with folic acid and antioxidant vitamins on homocysteine levels and LDL oxidation in coronary patients.

Hyperhomocysteinemia is an important cardiovascular risk factor. Serum homocysteine levels are specially dependent on folate nutritional status. In addition, the oxidative modification of low-density lipoproteins (LDLs) in the endothelial microenvironment is a damaging factor that can be modified with fat-soluble antioxidant vitamins. The present study was done to assess the effect of a supplementation of folic acid and antioxidant vitamins on homocysteine levels and in vitro LDL oxidation in patients with coronary artery disease. Twenty-three patients with angiographically proven coronary artery disease were given supplements for 15 d consisting of one capsule twice a day of a multivitamin preparation containing 0.65 mg folic acid, 150 mg alpha-tocopherol, 150 mg ascorbic acid, 12.5 mg beta-carotene, and 0.4 microgram vitamin B12. Serum lipids, vitamin and homocysteine levels, and in vitro LDL oxidation were measured before and after the supplementation period. During the supplementation period, serum folate levels increased from 5.0 +/- 1.5 to 10.8 +/- 3.8 ng/mL (P < 0.001), vitamin B12 increased from 317.4 +/- 130.4 to 334.5 +/- 123.8 pg/mL (P < 0.05), and alpha-tocopherol increased from 8.2 +/- 5.1 to 13.7 +/- 7.9 mg/L (P < 0.001). Serum homocysteine levels decreased from 8.7 +/- 4.3 to 6.3 +/- 2.2 mumol/L (P < 0.001). In vitro LDL oxidation decreased from 2.6 +/- 1.1 to 1.6 +/- 1.1 nmol malondialdehyde/mg protein (P < 0.001). In comparing patients with healthy controls, basal levels of folate were lower in the patients, whereas vitamin B12, alpha-tocopherol, and homocysteine levels were similar. No changes in serum lipid levels or body weight were observed. In conclusion, a short-term supplementation with folic acid and antioxidant vitamins can reduce serum homocysteine levels and in vitro LDL oxidation in patients with coronary artery disease.

Antioxidants↗
PubMed2000

Rapid and complete extraction of phenols from olive oil and determination by means of a coulometric electrode array system.

Extraction methods to determine olive oil phenols are not exhaustive. A procedure to test their effectiveness, based on the treatment of the extracted oil with 2 N HCl followed by analysis of phenols in the aqueous phase, has been developed. It was concluded, using this test, that 15-40% of phenols remained unextracted when the liquid/liquid extraction method with 80% methanol was applied. Solid phase extraction (C(18) cartridge) succeeded in retaining most of the phenols in the cartridge, but the recovery yield from the sorbent material was low. However, a new extraction method, based on the use of N,N-dimethylformamide (DMF) as an extraction solvent, achieved a complete extraction of phenols from oils. The proposed method requires a lower amount of oil, solvents, energy, and labor than the traditional ones. Because of the low concentration of phenols in the DMF extract, the highly sensitive electrochemical detector (EC) technique was studied. All of the phenols detected by the traditional UV detectors were also detected by EC using a coulometric array system. A rapid and complete analytical methodology of phenols in olive oil has been proposed based on coupling DMF extraction and EC detection.

Chromatography, High Pressure Liquid↗
PubMed2000

Sialoblastoma.

Tumours of the salivary gland are very uncommon in children. We present a case of sialoblastoma, a very rare congenital salivary-gland tumour, initially recognised on antenatal ultrasound. After histological diagnosis, a superficial parotidectomy was performed at 21 days of age with preservation of the facial nerve. There is no recurrence at2 years.

Female↗
PubMed2000

Clinical outcome of patients with familial hypercholesterolemia and coronary artery disease undergoing partial ileal bypass surgery.

Familial hypercholesterolemia is characterized by high serum levels of total cholesterol and LDL-cholesterol. It may be homozygous or heterozygous. In homozygous patients, LDL-cholesterol levels range from 500 to 1000 mg/dL and coronary artery disease is precocious, usually manifesting itself between the 2nd and 3rd decades of life. The diagnosis is often made by the presence of xanthoma tuberosum and tendinous xanthomas that appear between the 1st and 2nd decades of life. The use of high doses of statins or even unusual procedures (apheresis, partial ileal bypass surgery, liver transplantation, gene therapy), or both, is necessary for increasing survival and improving quality of life, because a reduction in cholesterol levels is essential for stabilizing the coronary artery disease and reducing xanthomas. We report our experience with 3 patients with xanthomatous familial hypercholesterolemia and coronary artery disease, who underwent partial ileal bypass surgery. Their follow-up over the years (approximately 8 years) showed a mean 30% reduction in total cholesterol, with a significant reduction in the xanthomas and stabilization of the coronary artery disease.

Adult↗
PubMed2000

[Serologic response against hepatitis C virus as a predictive factor to the treatment with interferon].

AIM: Serologic response of patients with chronic hepatitis C (CHC) was studied as a predictor of response to IFN therapy and we evaluated the correlation between such response with gender, risk factor, serum ferritin, GGT, Knodell's index and fibrosis. MATERIALS AND METHODS: A study was carried out in 40 patients with CHC who were treated with interferon-alpha 3 MU 3 times weekly 48 weeks. The diagnosis of hepatitis C was made based upon Inmuno-Blot (core, NS3, NS4 y NS5) and confirmed by detection of HCV-RNA in serum. Responses were evaluated (normal ALT and undetectable HCV-RNA in serum) at three months, at the end of treatment and six months after treatment. RESULTS: No significant differences were observed in responses at three months with regard to gender (47% males responded versus 55% females, n.s.), source of infection (50% intravenous drug users versus 50% non intravenous drug users; n.s.) and GGT level (50% with high levels versus 50% with normal levels, n.s.); however 25% of patients with high level of serum iron responded versus 59% with normal values (p = 0.04) and 28% of patients with fibrosis at liver histopathology responded versus 82% without fibrosis (p = 0.0006). No differences were observed at the response rates with regard to levels of core (20.1 SD:4 versus 19.5 SD:2.2, n.s.), NS3 (18.6 SD:7 versus 17.1 SD:7.3, n.s.) and NS4 (14.3 SD:7.7 versus 10.5 SD:9.2, n.s.). However NS5 levels in responders were 2.5 (0-16) versus 5.2 (0-16.5) in nonresponders (p < 0.05) and score in Knodell's index was 6.1 SD:2.6 in responders versus 9.2 SD:2.4 in nonresponders (p = 0.006). 47% of responders relapsed 6 months after the end of treatment with IFN. CONCLUSIONS: Titers of anti-NS5 showed predictive value of response as opposed to anti-core, anti-NS3 and anti-NS4 and it may justify its determination in the assessment of a patient with CHC at centers without capacity for measuring genotype and viral load. Low level of serum iron and Knodell's index like absence of fibrosis at liver histopathology were also variables with predictive value of response, as opposed to gender, GGT level and source of infection.

Adolescent↗
PubMed1999

Phenolic compounds in Spanish olive oils.

Phenolic compounds in Spanish virgin olive oils were characterized by HPLC. Simple phenols such as hydroxytyrosol, tyrosol, vanillic acid, p-coumaric acid, ferulic acid, and vanillin were found in most of the oils. The flavonoids apigenin and luteolin were also found in most of the oils. The dialdehydic form of elenolic acid linked to tyrosol and hydroxytyrosol was also detected, as were oleuropein and ligstroside aglycons. The structure of a new compound was elucidated by MS and NMR as being that of 4-(acetoxyethyl)-1,2-dihydroxybenzene. Changes of phenolic compounds in virgin olive oils with maturation of fruits were also studied. Hydroxytyrosol, tyrosol, and luteolin increased their concentration in oils with maturation of fruits. On the contrary, glucoside aglycons diminished their concentration with maturation. No clear tendency was observed for the rest of the phenolic compounds identified.

Chromatography, High Pressure Liquid↗
PubMed1999

Effect of dietary hydrogenated fish oil on the plasma lipoprotein profile and on the fatty acid composition of different tissues on the rat.

Dietary fatty acids are actively incorporated into membrane lipids, and fat intake can modify the composition and the biochemical activity of cellular membranes and the pattern of plasma lipoproteins. Industrial hydrogenation of polyunsaturated oils leads to the formation of isomeric trans fatty acids which are incorporated into cellular membranes when they are present in the diet. The trans fatty acid amount present in hydrogenated oils depends on the degree of hydrogenation, being high for partially hydrogenated oils and low for highly hydrogenated oils. Hydrogenated fish oil is widely used in some countries for the production of margarine and industrial fats. This study compares the fatty acid composition of plasma, erythrocytes, subcutaneous adipose tissue, and hepatic microsomal membranes and the plasma lipoprotein profile after feeding rats with a synthetic diet containing either fish oil, partially hydrogenated fish oil, or highly hydrogenated fish oil. It is observed that the tissue content of monounsaturated fatty acids increases and that the content of polyunsaturated fatty acids decreases after an increase of the degree of hydrogenation of the dietary fat. Tissues from animals fed partially hydrogenated fish oil show significant amounts of trans fatty acids only. The plasma triacylglyceride composition and the lipoprotein profile are also altered by the degree of hydrogenation of the dietary fat. Triacylglycerides decrease after highly hydrogenated fat feeding only. Total cholesterol and low-density lipoprotein cholesterol are significantly increased after partially hydrogenated fat feeding. Although no direct evidence is presented, this effect may be attributable to the high content of trans isomers of this dietary fat which nutritionally may behave as saturated fatty acids.

Adipose Tissue↗
PubMed1999

[New pieces in the puzzle of atherogenesis].

The contribution of high serum levels of cholesterol to atherogenesis has been widely recognized, but the mechanisms are not completely clear. Numerous publications have emphasized that oxidized, but not native low-density lipoproteins, are the particles incorporated into the arterial wall. A group of receptors generically called "scavenger" (SR), actively bind these modified lipoproteins and incorporate them into monocytes-macrophages, in the arterial intima. SR are not down regulated by intracellular concentrations of cholesterol, thus accumulating huge amounts of lipids, transforming monocyte-macrophages into foam cells, predominant cell type of the fatty streak. The simultaneous cytokine production and migration of other cellular types progressively transform this initial lesion into the organized atherosclerotic plaque. In this setting SR, which are up-regulated by oxidized LDL, play a central promoting role. Its presence has been demonstrated in arterial plaques both in human and animal models, and its blockade protects animals from development or progression of atherosclerosis. In humans, elevated antibody titers to oxidized LDL in patients with coronary stenosis, and increased SR activity, in pro-atherogenic conditions such as haemodialysis, indicate that this model may operate as well, but the evidences are still not solid enough to definitively conclude that the oxidized-LDL-SR hypothesis is a finished puzzle.

Animals↗
PubMed1998

Effect of the degree of hydrogenation of dietary fish oil on the trans fatty acid content and enzymatic activity of rat hepatic microsomes.

The degree of fat hydrogenation and the trans fatty acid content of the diet affect the fatty acid composition of membranes, and the amount and the activity of some membrane enzymes. We describe the effects of four isocaloric diets containing either sunflower oil (SO, 0% trans), fish oil (FO, 0.5% trans), partially hydrogenated fish oil (PHFO, 30% trans), or highly hydrogenated fish oil (HHFO, 3.6% trans) as fat sources on the lipid composition and the trans fatty acid content of rat hepatic microsomes. We also describe the effect of these diets on the cytochrome P-450 content and on the aminopyrine N-demethylase, aniline hydroxylase, and UDP-glucuronyl transferase microsomal activities. Cytochrome P-450 content was dependent on the degree of unsaturation of the diet, being higher for the FO-containing diet and lower for the HHFO diet. Aminopyrine N-demethylase activity also correlated with the degree of unsaturation of the diet as did the cytochrome P-450 content did (FO > SO > PHFO > HHFO). Aniline hydroxylase activity appeared to be independent of the degree of unsaturation of the dietary fat, but correlated with the trans fatty acid content of the diet, which was also reflected in the trans content of the microsomal membranes. UDP-glucuronyl transferase activity was higher for the FO-containing diet than for the SO diet, showing intermediate values after the PHFO and HHFO diets.

Animals↗
PubMed1998

Objective computerized fetal heart rate analysis.

OBJECTIVE: To assess the validity of a computerized methodology for cardiotocogram analysis based on a recently described reproducible visual estimation of the baseline. METHODS: Forty-two antepartum and 43 intrapartum cardiotocograms (CTGs) acquired by a personal computer were selected. Antepartum tracings were performed in the 48 h that preceded an elective cesarean section, and intrapartum tracings were performed until delivery. FHR baselines were estimated by an expert, according to an objective and reproducible methodology. Using these baselines, automated detection of accelerations and decelerations and estimation of variability was performed by the personal computer. A quantitative adaptation of the FIGO guidelines for fetal monitoring was used to classify tracings. Perinatal outcome was classified according to the Apgar score and umbilical arterial pH. Validity was then assessed by the proportions of agreement (PA), kappa statistic (K), sensitivity and specificity, with 95% confidence intervals (95% CI). Cases showing a disagreement between CTG and perinatal classification were reviewed and an adjustment in baseline definition was tested. RESULTS: The initial overall PA and kappa between CTG and perinatal classification were, respectively, 0.79 (95% CI: 0.69-0.87) and 0.62 (95% CI: 0.41-0.83). The overall PA and K, after baseline adjustment were, respectively, 0.89 (95% CI: 0.81-0.95) and 0.78 (95% CI: 0.58-0.98). Sensitivities and specificities ranged between 79% (95% CI: 60-92%) and 100% (95% CI: 95-100%). CONCLUSIONS: Good clinical prediction may be possible with an objective methodology for cardiotocogram analysis based on a recently described reproducible baseline estimation.

Cardiotocography↗
PubMed1998

[Eradication of Helicobacter pylori by triple therapy in ulcerous patients: the role of endoscopy and antibiotic sensitivity].

BACKGROUND: A protocol was conducted to evaluate the compliance and results of Helicobacter pylori infection treatment in patients with ulcer disease. To know the metronidazole, clarithromycin and amoxicillin activities of Helicobacter pylori strains from such patients. PATIENTS AND METHODS: 35 patients with ulcer disease (27 duodenal ulcer and 8 gastric ulcer) were studied. Diagnosis of Helicobacter pylori infection was performed by urease test and culture of mucosal gastric samples from patients undergoing endoscopy. The patients received the following treatment during 7 days: omeprazole (20 mg bid), clarithromycin (500 mg bid) and amoxicillin (1 g bid), OCA x 7. Susceptibility was determined by E-test system on Wilkins-Chalgren blood agar and read after 5 days. RESULTS: 22/24 patients who had completed the protocol design eradicated Helicobacter pylori (91.7%), 11 patients (31.4%) refused second endoscopy to verify control of eradication. After treatment 10 patients presented with pyrosis "de novo" (28%). The overall metronidazol, claritromycin and amoxicillin resistance rate was 50%, 1.5% and 0% respectively. CONCLUSIONS: OCA x 7 treatment obtains a eradication rate higher than 90% in our patients with ulcer disease, despite smoking habit, but with a significative number of patients presenting pyrosis after treatment. We recommend a non-endoscopy method to verify eradication rate, because of its poor acceptance. 3. Metronidazol resistance rate is high in our series but clarithromycin susceptibility is maintained.

Adult↗