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F Valdés

Publications and source records attributed to F Valdés.

At least 19 recordsLinked to original sources
PubMed2006

DPPH radical scavenging activity of two flavonol glycosides from Aconitum napellus sp. lusitanicum.

The DPPH radical scavenging activity of two flavonol glycosides obtained from ethanolic extracts of Aconitum napellus sp. lusitanicum was studied. The results showed a high DPPH antiradical activity of compound 1 (quercetin 3-O-(6-trans-caffeoyl)-beta-glucopyranosyl-(1-->2)-beta-glucopyranosyl-7-O-alpha-rhamnopyranoside) when compared with compound 2 (quercetin-3-sophoroside-7-rhamnopyranoside), rutin and ascorbic acid. The relationship between the caffeoyl and rhamnopyranoside groups in the flavonol glycosides structures and the DPPH antiradical activity was also discussed.

Aconitum↗
PubMed2006

Posttransplant diabetes mellitus in renal allograft recipients: A prospective multicenter study at 2 years.

The purpose of this study was to investigate the incidence and risk factors for the development of diabetes mellitus after kidney transplantation (PTDM). A total of 1783 nondiabetic renal allograft recipients transplanted from January 2000 to December 2002 were included. Diabetes was diagnosed following American Diabetes Association criteria. While 1276 patients were treated with tacrolimus (Tac), mycophenolate mofetil (MMF), and steroids, 507 patients received cyclosporine-ME (CsA), MMF, and steroids. PTDM incidence at 6, 12, and 24 months was 14.2%, 12.8%, and 13.3%, respectively. Cumulative incidence during the follow-up was 21.6%. Only 121 of the diabetic patients (47.6%) at 6 months remained diabetic at 24 months. Furthermore, 60 patients of 116 patients on insulin at 6 months (51.7%) remained on treatment at 24 months. The cumulative incidence of PTDM was similar in the two immunosuppressive treatments (19.7% on CsA-MMF vs 22.3% on Tac-MMF; P = NS). However, at 24 months, 14 of 50 diabetic patients on CsA-MMF (28%) and 74 of 161 patients on Tac-MMF (45.9%) were on insulin treatment (P < .05). By Cox regression analysis, age older than 60 years (RR 1.61; 95%CI 1.28-2.04; P < .001), body mass index (BMI) > 30 kg/m2 at transplantation (RR 1.66; 95%CI 1.27-2.16; P < .001), and immunosuppression with Tac (RR 1.30; 95%CI 1.02-1-66; P = .033) were associated with PTDM. In conclusions, the incidence of PTDM at 24 months in immunosuppressive protocols including MMF is about 22%, and it is associated with older age, increased BMI, and immnunosuppression with Tac.

Adrenal Cortex Hormones↗
PubMed2006

[Vitamin C].

Vitamin C or ascorbic acid is a hydrosoluble vitamin derived from glucose metabolism. It acts as a reductor agent required for synthesis of collagen fibers through hydroxylation of proline and lysine. It also protects the body against damage caused by the free radicals. Humans cannot synthesize ascorbic acid as they lack an enzyme called gulonolactone oxidase. Concentrations in plasma and leukocytes reflect the levels of the diet and body deposits respectively of this vitamin. Among foods with high vitamin C levels are tomatoes, potatoes, and citrus fruits such as limes, oranges and lemons. The current recommendation of daily intake of vitamin C is 90 mg/d for men and 75 mg/d for women. Patients with chronic diseases such as cancer or diabetes or those who smoke need higher doses in their usual diet. Ascorbic acid deficiency gives rise to the appearance of scurvy. This disease is rarely seen in developed countries. The symptoms develop with plasma levels below 0.15 mg/dL. Scurvy is characterized by the presence of weakness, joint pain or skin lesions in form of petechias, gum bleeding, ease of developing bruises or delay in wound healing. The most characteristic skin manifestations are purpuric perifollicular hyperkeratotic papules and the presence of kinky hair.

Antioxidants↗
PubMed2006

Biosynthesis of antitumoral and bactericidal sanguinarine.

A simple, rapid, and reliable TLC method for the separation and determination of sanguinarine has been established. This intensively studied biologically active alkaloid has a wide range of potentially useful medicinal properties, such as antimicrobial, antiinflammatory, and antitumoral activities. Sanguinarine has also been incorporated into expectorant mixtures and has a strong bactericidal effect upon gram-positive bacteria, particularly Bacillus anthracis and staphylococci. These medicinal properties are due to the interaction of sanguinarine with DNA. A fibre-optic-based fluorescence instrument for in situ scanning was used for quantitative measurements. The sanguinarine was determined over the range 5-40 ng and a detection limit of 1.60 ng. The method was applied to the quantification of sanguinarine in tissue culture extracts of Chelidonium majus L.

Journal Article↗
PubMed2006

[Renal transplantation in the northwest of Spain: analysis of the activity in the region of Galicia].

BACKGROUND: Spain is the world leader in organ transplant rates, and the national average is maintained in the northwestern Spanish region of Galicia. However, there is no official registry recording transplantation results in this region. In this paper we report a study of patient and graft survival and risk factors among kidney transplant patients in Galicia between January 1996 and December 2000. METHODS: Patients receiving kidney transplants in Galicia in the above period were monitored up to the end of 2001, deaths and graft losses were recorded and analysed by actuarial and Kaplan-Meier methods, and possible risk factors for death and graft loss were evaluated using Cox's proportional hazards model. RESULTS: In the study period, 672 kidneys were transplanted, all from deceased donors. Graft and patient survival rates were respectively 80% and 94% after 1 year, and 67% and 83%, after 5 years. Two-thirds of graft losses occurred within the first year and the most common cause was vascular thrombosis (44%). Independent risk factors for graft loss were donor asystole (relative risk [RR] = 3.41, 95% confidence interval [CI]: 1.73-6.73), donor age (RR = 1.54, CI: 1.05-2.27 for 40-60-year-olds, RR = 2.59, CI: 1.66-4.07 for over-60s, relative to under-40s), donation from outside the institution in which implant was performed (RR = 1.43, CI: 1.02-2.02), acute rejection (RR = 2.32, CI: 1.63-3.22), and retransplantation (RR = 1.56, CI: 1.03-2.37). The main causes of death were infections (38%), followed by cardiovascular pathologies (30%) and tumours (11%). CONCLUSIONS: The kidney transplant rate varies excessively within Galicia; the global rate is 50 per million inhabitants per year. Patient survival is similar to those recorded in national registers, but graft survival is deficient, apparently due to a high incidence of vascular thrombosis.

Adolescent↗
PubMed2005

Dianthramide glucosides from tissue cell cultures of Delphinium staphisagria L.

Tissue cell cultures of Delphinium staphisagria L. produced three dianthramide glucosides N-(2'-beta-glucopyranosylsalicyl)-5-hydroxyanthranilic acid methyl ester, N-(2'-beta-glucopyranosyl-5'-methoxysalicyl)-5-hydroxyanthranilic acid methyl ester and N-(2'-beta-glucopyranosyl-5'-hydroxysalicyl)-5-hydroxy-6-methoxyanthranilic acid methyl ester, together with known methyl esters of N-salicylanthranilic acid and N-(2'-beta-glucopyranosyl-5'-hydroxysalicyl)-5-hydroxyanthranilic acid. Structures of the glucosides were established by MS, 1-D and 2-D NMR techniques.

Cells, Cultured↗
PubMed2005

Kidney-pancreas transplants: is it so difficult to start a program?

BACKGROUND: For selected patients with type 1 diabetes mellitus and end-stage renal failure, simultaneous kidney-pancreas (SKP) or pancreas after kidney (PAK) transplantation is the treatment of choice. However, it is frequently difficult to start a program for fear of serious intraabdominal complications in an immunosuppressed patient. We review our initial experience with these transplantations. METHODS: Twenty-three patients (20 SKP, 3 PAK) with type 1 diabetes mellitus received transplants between June 2000 and October 2003. All received immunosuppression therapy with thymoglobulin, prednisone, tacrolimus, and mycophenolate mofetil. The operation included portal venous drainage and exocrine enteric drainage. Rejections were biopsy-proved. Cytomegalovirus prophylaxis with gancyclovir was administered. RESULTS: The mean follow-up is 13 months (range, 1-30 months) for recipients of mean age 39 +/- 7 years (17 men, 6 women). Mean cold ischemia time for kidney was 10.2 +/- 3.9 hours, and for pancreas was 10.5 +/- 3 hours. The rate of initial graft function was 100%. Graft rejection rate was 8%. The repeat laparotomy rate was 53% (12 patients), with a mean of 0.8 procedures per patient (range, 0 to 5). At the end of follow-up, patient survival was 95%, kidney survival was 85%, and pancreas survival was 83%. Patients with a functioning graft were insulin-free, with a mean fasting glucose concentration of 79 +/- 7 mg/dL, hemoglobin A1C of 4.5% (range, 4% to 4.9%) C-peptide of 5.9 ng/mL (range, 2.1 to 12 ng/mL), and a mean serum creatinine level of 1.6 mg/dL (range, 0.9 to 4.6 mg/dL). There was 1 death, due to posttransplantation lymphoproliferative disease confined to the pancreatic graft and abdominal sepsis at 3 months posttransplantation. CONCLUSIONS: Our results are similar to those of other series of SPK or PAK transplantations: low acute rejection rates, frequent requirement for repeat laparotomy, and good patient and graft survival, permitting an excellent quality of life.

Adult↗
PubMed2005

Renal transplantation from non-heart-beating donors: a single-center 10-year experience.

BACKGROUND: Reluctance to accept non-heart-beating donors (NHBD) as a source of kidneys, is due to medical, ethical, and logistical reasons. Evidence suggest that the short-term graft survival is similar to that of kidneys obtained from heart-beating donors (HBD). However, few studies, with long-term follow-up are available. We conducted a single-center study of kidneys obtained from NHBD, in a 14-year period. METHODS: We studied 100 patients transplanted with kidneys between 1989 and 2004, using NHBD, supported by heart compression and mechanical ventilation (n = 24), intravascular in situ cooling (n = 59), or cardiorespiratory resuscitation plus manual abdominal counterpulsation without cooling (n = 17), the last technique being used from 1998. The median follow-up was 51 +/- 51 months (range, 1 to 170). The outcomes of these procedures were compared to those of 1025 transplantations of kidneys from HBD performed during the same period. RESULTS: The characteristics of the recipients did not differ significantly between the two groups. Kidneys from NHBD showed a significantly higher rate of delayed graft function (DGF; 84% vs 26%; (P < .001), furthermore, the primary nonfunction (PNF) incidence was significantly higher with NHBD vs HBD (16% vs 10%; P < .001). The incidence of acute rejection episodes (ARE) within 3 months and at 1 year did not differ between the groups of donors; however, more NHBD kidneys were lost from ARE. The short-term (3-month and 1 year) and long-term (5 and 10 years) renal function, determined by the serum creatinine levels, and patient and graft survival were not different for kidneys obtained from NHBD. CONCLUSIONS: The incidences of PNF and DGF were significantly higher with NHBD, which produced poorer renal function at the time of hospital discharge. One-, 5-, and 10-year graft survivals and renal function did not differ between NHBD and HBD grafts. In our series, PNF was the main barrier to the use of NHBD.

Adult↗
PubMed2005

[Risk factors for refusing kidneys in Galicia. Is it possible to increase its use?].

INTRODUCTION: Demographic changes along with an increase in the demand of organs and an increase in the expertise of transplantation teams, lead to a constant modification of donors' characteristics and, accordingly, of the supply of the organs used and refused. OBJECTIVE: Analyze the use and refusal of kidneys generated in Galicia. Subjects and method. A follow-up of kidney donors was carried out between 1996 and 2000, studying the reasons for non extraction and refusal of kidneys and analyzing the influence that donors' characteristics have on them. In order to evaluate the risk factors of not using grafts, multiple logistic regression patterns were made, assessing odds ratios with confidence intervals at 95%. RESULTS: 836 kidneys were recovered from 433 donors, and 697 were implanted out of them. 17% of the organs extracted, a percentage approaching 25% in the two latest years, were discarded, due to the biopsy findings (27%), donor's previous conditions (22%), anatomical disorders (16%), prolonged cold ischemia (12%) or recipient not located or unsuitable (14%). The average age of refused grafts was significantly higher than that of implanted ones, in such a way that having more than 45 years old was an independent risk for refusing kidneys (OR = 1.76 and p = 0.05, for 45-59 years old; OR = 6.1 and p = 0.000, for older than 60 years old). The same happened with history of hypertension (OR = 1.59 and p = 0.044), high serum creatinine level (OR = 1.83 and p = 0.005) and positive serology for HCV (OR = 5.65 and p = 0.001) and anti-HBc (OR = 2.91 and p = 0.017). CONCLUSIONS: Elderly donors and donors with concomitant diseases enable us to increase the number of grafts, although they also lead to an increase in refusals, which nearly amounts to 20% of the ones generated. However, more than the half were refused due to pontentially avoidable reasons and therefore these could have been valued for transplantation to limit recipients.

Adult↗
PubMed2003

Quantitation and comparison of anti-Gal-alpha-1,3-Gal antibodies in sera of healthy individuals and patients waiting for kidney transplantation.

Highly sensitized patients have poor prospects of being offered an allogeneic donor transplant, therefore, they could become primary candidates for xenogeneic organ transplantation. Hyperacute rejection is initiated by anti-Gal-(alpha)-1,3-Gal antibodies (xenoAb) and this rejection will have to be avoided if xenotransplantation is introduced into clinical practice. Hence, the aim of the study was to determine if sensitized patients against HLA antigens have higher titers of xenoAb than nonsensitized individuals. We determined immunoglobulin (Ig)M and IgG xenoAb in the serum of 100 volunteer blood donors and 98 sensitized patients and compared antibody titers from nonsensitized individuals to those with HLA specific antibodies classified into 5 panel-reactive antibody (PRA) groups: I, 0%; II, >0% and < or =10%; III, >10% and < or =50%; IV, >50% and < or =80%; and V, >80%. Analysis of the isotype specific quantification of the xenoAb revealed great interindividual variation but there were no significant differences in the range of titers of xenoAb. No significant PRA group-related variations were observed for xenoAb. In fact, there was no demonstrable correlation between levels of PRA and levels of xenoAb because the scattergram showed no statistically significant association by nonparametric statistic analysis. The results presented herein revealed that the presence of HLA specific antibody has no demonstrable relationship to the presence of higher titers of xenoAb. Thus, sensitized patients do not present a greater risk of rejection or are more difficult to treat for natural xenoreactivity than nonsensitized patients.

Antibodies↗
PubMed2003

Budesonide ameliorates early portal hypertension in the rat: possible antiexudative splanchnic action.

Major portal pressure increase occurs on the second day post-stenosing-ligation of the portal vein in the rat and it is associated with pancreatic edema, intraperitoneal free exudate, hypoalbuminemia and hypoproteinemia. All this suggests the development of a regional exudative inflammatory response. In order to verify this hypothesis the steroid budesonide, whose antiinflammatory activity could prevent these alterations, was administered to rats with prehepatic portal hypertension. Wistar male rats were divided into the following groups: Control rats that were administered saline solution (CS; n = 10), Control rats that were administered budesonide (36 mg/kg per day; CB; n = 10), triple stenosing ligation of portal vein (TSLP) with saline solution (n = 10) and triple stenosing ligation of portal vein with budesonide (36 mg/kg per day; n = 10). In rats with prehepatic portal hypertension at 48 h of postoperative evolution, budesonide decreases the incidence of pancreatic edema, of peritoneal free exudate, of mesenteric adenopathies and prevents hypoproteinemia, hypoalbuminemia and hyper-beta-globulinemia. Some of the macroscopic intra-abdominal alterations and some of the changes in the electrophoretic pattern found in portal hypertensive rats could have an inflammatory etiopathogeny because budesonide shows an effective prophylaxis.

Journal Article↗
PubMed2003

[Multicenter study of darbepoetin alfa in the treatment of anemia secondary to chronic renal insufficiency on dialysis].

This Spanish single-arm, multicenter, prospective clinical trial assessed the maintenance of hemoglobin concentrations (Hb) between 10-13 g/dL with unit doses of darbepoetin alfa and the safety of the treatment in dialysis patients. Eight-hundred twenty-six patients with chronic renal failure (CRF) (94% receiving haemodialysis and 6% receiving peritoneal dialysis) previously maintained on stable recombinant human erythropoietin (r-HuEPO) therapy with stable hemoglobin (Hb) concentrations (mean Hb concentration = 11.7 g/dL) were switched to darbepoetin alfa at a reduced dosing frequency for 24 weeks (a 20-week titration phase plus a 4-week treatment evaluation phase). Subjects receiving r-HuEPO two or three times weekly were switched to darbepoetin alfa once weekly, and those. who were receiving r-HuEPO once weekly were switched to darbepoetin alfa once every two weeks. The initial dose of darbepoetin alfa was determined from the r-HuEPO dose at inclusion into the study using a formula equating the peptide mass of the two molecules and rounding to the nearest available prefilled syringe dose. Overall, 86.8% of patients completed the 24-weeks of study. Changing the treatment from r-HuEPO to darbepoetin alfa and increasing the dose interval did not result in any clinically significant change in the Hb concentration. From base-line to the evaluation phase, the mean Hb fell 0.09 (95% CI, -0.2; -0.0) g/dl, with an increase of 0.19 (95% CI, 0.0;0.3) g/dL i.v. and a decrease of 0.22 (95% CI, -0.3; -0.1) g/dL s.c.). This maintenance of the mean Hb concentration was accompanied by a mean 9.8% reduction of the darbepoetin alfa dose (19.7% (95% CI, -24.9; -14.2) i.v. and 4.7% (95% CI, -8.5; -0.7) s.c. Treatment with darbepoetin alfa was well tolerated and no unexpected adverse events were reported. In conclusion, the replacement of previous r-HuEPO treatment by darbepoetin alfa in the therapy of anemia secondary to chronic renal failure in diaiyzed patients was effective, well tolerated, and decreased the frequency of dose administration compared with the previous r-HuEPO treatment. Darbepoetin alfa administered once weekly or once every two weeks maintained the baseline Hb levels whilst allowing dose reduction, which was higher in patients receiving i.v. darbepoetin alfa.

Aged↗
PubMed2003

[Prognostic markers determining the start of dialysis].

BACKGROUND: It is widely known that renal disease progresses towards the terminal stage regardless of the cause. The aim of this study is to identify prognostic factors in the progression that determine the start of dialysis. METHODS: From january 1998 until december 1999, 76 patients diagnosed with renal failure were monitored, 52 of whom started dialysis treatments. Clinical and analytical variables were studied. An actuarial analysis was carried out following the methodology of Kaplan-Meier to determine the likelihood of the need for dialysis and the Cox proportional risk analysis was also used. RESULTS: The patients enrolled in this study were between 20 and 78 years of age. 49 (64.5%) of the subjects were men and 27 (35.5%) were women. The most prevalent pathology was nephroangiosclerosis (26.3%), followed by diabetes (25.0%). During the monitoring program, 68.4% of the patients began dialysis treatments (table I). Systolic blood pressure, haemoglobin and the total proteins were univariately identified as prognostic variables. 89.47% and 71.58% of the patients with a systolic blood pressure reading of under 140 mmHg had not begun dialysis after 12 and 24 months respectively. 87.02% and 53.63% of the patients with a systolic blood pressure reading of over 140 mmHg had not begun dialysis after 12 and 24 months respectively (p = 0.025) (fig. 1). With a haemoglobin level higher than 10 gr/dl after 12 months 92.7% had not started dialysis, dropping to 72.33% after 24 months. With a haemoglobin level of under 10 g/dl 78.6% and 37.59% had not started dialysis after 12 and 24 months respectively (p = 0.0008) (fig. 2). Taking into account the mean values of different variables in the two year period prior to starting or not starting dialysis, it was found that haemoglobin significantly affected the risk of the need to start dialysis treatments [RR = 0.729; 95% CI = (0.554;0.959)], while systolic blood pressure was on the borderline of statistical significance (table IV). CONCLUSIONS: Haemoglobin levels significantly affect the risk of the need to start dialysis treatments, while other variables were identified as possible prognostic factors.

Adult↗
PubMed2002

Restriction in the usage of variable beta regions in T-cells infiltrating valvular tissue from rheumatic heart disease patients.

Rheumatic Heart Disease (RHD) is a delayed consequence of a pharyngeal infection with group A streptococcus (GAS), usually ascribed to a cross-reactive immune response to the host's cardiac tissues. Several GAS proteins have been reported to be superantigens, also raising the possibility that T cells in RHD could be driven by superantigens. We therefore analysed the variable beta (V beta) repertoire of T cells infiltrating heart valves from chronic RHD patients undergoing elective valvular surgery. We analysed 15 valve specimens from patients with longstanding quiescent RHD and control valves from four non-rheumatic individuals. Total RNA was extracted from fresh valve tissue and employed to amplify 22 V beta genes by RT-PCR. In valvular tissue, a restricted number of only 2 to 9 V beta regions were detected as opposed to the findings in control valves. In 8 RHD valves, the expression of V beta1, 2, 3, 5.1, 7, 8, 9 or 14 was marked. These V beta regions have been related to GAS superantigens. Our results evidence the presence of a restricted set of T lymphocytes in valvular tissue from a majority of patients with chronic RHD and suggest that valvular sequelae in these patients might be related to a local antigen or superantigen driven inflammatory process that persists even many years after the initial triggering event.

Adult↗