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A Alonso García

Publications and source records attributed to A Alonso García.

8 recordsLinked to original sources
PubMed2004

Development of a rapid method based on solid-phase extraction and liquid chromatography with ultraviolet absorbance detection for the determination of polyphenols in alcohol-free beers.

An analytical method based on solid-phase extraction (SPE) and followed by liquid chromatographic separation and ultraviolet detection (HPLC-UV) is proposed for the determination of 10 phenolic compounds which participate on beer stability and sensory properties in alcohol-free beers. Acetonitrile was found to be the most appropriate solvent for the elution of polyphenolic compounds adsorbed on C18 cartridges. The performance of the method was assessed by the evaluation of parameters such as absolute recovery (generally higher than 60%), repeatability (lower than 10%), linearity (r2 higher than 0.993) and limits of quantitation (ranging from 1 to 37 microg/L); no matrix effects were observed. The polyphenol content of different Spanish alcohol-free beers is presented. Five phenolic compounds such as protocatechuic, p-coumaric, ferulic, caffeic acids, and (+)-catechin were identified at levels lower than 10 mg/L.

Beer↗
PubMed1998

[Complications of plateletpheresis procedures].

PURPOSE: Thrombopheresis procedures have been recently expanded with the development or different programmes. Taking into account that this reasonably safe procedure is not devoid of complications, it would be desirable to select those individuals with lower risk of suffering adverse side effects as donors. The thrombopheresis procedures performed in our hospital between 1986 and 1997 were analysed in order to establish the useful guidelines for such selection. MATERIAL AND METHODS: All the thrombopheresis procedures performed in the Asturias Central Hospital blood bank in the 1986-1987 period were analysed. The first procedure per donor, along with all data referred to adverse effects appearing during thrombopheresis, were collected. Sex, age, body, weight, blood cells count (before and after thrombopheresis) and serum calcium levels (before and after thrombopheresis) were taken as variables with predictive value for adverse effects. With regard to the procedure, the model of cell separator, the duration of the procedure, the amount and type of anticoagulant solution and the prophylactic use of calcium ions were assessed. RESULTS: A total number of 1,024 thrombophereses were analysed. Some types of adverse effect were seen in 259 instances (25.3%). Of these, 70.3%, were mild, 29.3% moderate and 0.4% severe. The commonest adverse effect was perioral paraesthesia. Of the different variables studied, female sex and low weight acquired predictive value with respect to the occurrence of adverse effects. Prophylactic administration of calcium did not prevent the appearance of complications. CONCLUSIONS: The thrombopheresis procedures may present adverse side effects in a high percentage of cases, which, although mostly mild, require specialised personnel for identification and management. Males weighing over 70 kg are less prone to suffer such effects. Oral administration of calcium before the apheresis does not prevent the adverse reactions.

Adult↗
PubMed1998

[Treatment results with external radiotherapy in prostate cancer].

OBJECTIVE: External irradiation is an accepted curative treatment modality for patients with localized prostatic tumor. The 15-year results in patients treated by radical irradiation alone are presented. The determinant prognostic factors for local tumor control and disease free survival are analyzed. METHODS: 135 patients with a histologically confirmed localized carcinoma of the prostate were treated at our department from May 1972 to January 1998. Fifty patients received Co-60 therapy; the linear accelerator and high energy photons were utilized in the remaining 80 patients. By tumor stage, 53 patients were B1, 49 B2 and 33 C. The mean follow-up was 61 months (range 1-180). Most patients were exposed to localized fields of irradiation; dose ranged from 50-74 Gy, fractionated at a dose of 180-200 cGy/day. RESULTS: Overall local tumor control was 77% at 5 years and 73% at 15 years, with a disease free survival of 63% and 45% at 5 and 15 years, respectively. Local tumor control at 13 years was 71% for stage B1, 82% for B2 and 70% for C. The disease free survival at 13 years for stages B1, B2 and C were 46%, 49% and 36%, respectively. The BD and MD tumors had a 15-year disease free survival of 48% vs 32% for the PD tumors (p = 0.005). Patients with PSA < or = 20 ng/ml before treatment showed a disease free survival of 87% vs 48% for those with PSA > 20 ng/ml ((p = 0.011). Multivariate analysis showed dose to be a determinant prognostic factor for local tumor control (0.0432); dose and histological grade were determinants for disease free survival (p = 0.029 and 0.033). CONCLUSIONS: This retrospective study found dose to be a determinant prognostic factor for local tumor control and both dose and histological grade were determinants for disease free survival. Radiotherapy is a therapeutic option for these patients. The results can be enhanced if the dose delivered to the prostate can be increased while maintaining the complication rate within the same ranges.

Aged↗
PubMed1996

[Surgical treatment of atrial fibrillation].

Atrial fibrillation is the most frequently found sustained arrhythmia. It increases the risk of thromboembolism and adversely affects cardiac performance because of loss of atrial kick. New surgical treatments of atrial fibrillation have been developed to ablate the origin of abnormal impulses on the atrium. The left atrial isolation and the corridor operation restores the regular rhythm, but do not reduce the risk of thromboembolism because the left atrium may continue to fibrillate. The maze operation has proven to be effective in both converting to sinus rhythm and regaining atrial contractility. However, this method is meticulous and time-consuming and takes more cardiac ischemic time, especially when other cardiac procedures are performed simultaneously.

Atrial Fibrillation↗