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G Del Río

Publications and source records attributed to G Del Río.

10 recordsLinked to original sources
PubMed1999

Alcoholysis reactions from starch with alpha-amylases.

The ability of alpha-amylases from different sources to carry out reactions of alcoholysis was studied using methanol as substrate. It was found that while the enzymes from Aspergillus niger and Aspergillus oryzae, two well-studied saccharifying amylases, are capable of alcoholysis reactions, the classical bacterial liquefying alpha-amylases from Bacillus licheniformis and Bacillus stearothermophilus are not. The effect of starch and methanol concentration, temperature and pH on the synthesis of glucosides with alpha-amylase from A. niger was studied. Although methanol may inactivate alpha-amylase, a 90% substrate relative conversion can be obtained in 20% methanol at a high starch concentration (15% w/v) due to a stabilizing effect of starch on the enzyme. As the products of alcoholysis are a series of methyl-oligosaccharides, from methyl-glucoside to methyl-hexomaltoside, alcoholysis was indirectly quantified by high performance liquid chromatography analysis of the total methyl-glucoside produced after the addition of glucoamylase to the alpha-amylase reaction products. More alcoholysis was obtained from intact soluble starch than with maltodextrins or pre-hydrolyzed starch. The biotechnological implications of using starch as substrate for the production of alkyl-glucosides is analyzed in the context of these results.

Aspergillus↗
PubMed1996

Single-dose rufloxacin versus 3-day norfloxacin treatment of uncomplicated cystitis: clinical evaluation and pharmacodynamic considerations.

The efficacy and safety of rufloxacin (400 mg, single dose) were compared to those of norfloxacin (400 mg twice a day for 3 days) for the treatment of women with uncomplicated cystitis. In addition, urine levels, drug level/MIC ratio, and urine antibacterial activity 72 to 84 h after treatment initiation were determined in a subgroup of patients for pharmacodynamic assessment. A total of 203 women were included and treated in this open, randomized clinical trial; 100 patients received norfloxacin, whereas 103 received rufloxacin. Of these, 156 (74 and 82 patients in the norfloxacin and rufloxacin groups, respectively) were considered bacteriologically evaluable. At the first follow-up visits (3 to 12 days after starting the treatment), bacteriological cure rates were 99 and 94% for norfloxacin and rufloxacin, respectively. Seventy-nine percent (119 of 150) of bacteriologically cured patients attended a long-term follow-up visit (4 to 6 weeks after starting the treatment), where a relapse rate of 4% (2 of 54) and 5% (3 of 64) were found in the norfloxacin and rufloxacin groups, respectively. The pharmacodynamic evaluation performed in 35 patients showed similar median urine levels (approximately equal to 25 micrograms/ml) and urine antibacterial activity for both treatment groups against initial isolates, despite a higher norfloxacin level/MIC ratio due to the lower MIC of norfloxacin. Twenty-one patients (20%) in the rufloxacin group and 12 patients (12%) in the norfloxacin group reported 39 and 16 adverse events, respectively, almost all of them being mild and lasting < 24 h. Overall, gastrointestinal reactions were the most frequent adverse events reported. However, 12 patients treated with rufloxacin reported 15 central nervous system adverse events. This study shows that single doses of rufloxacin are as effective as a norfloxacin 3-day standard treatment in uncomplicated cystitis. The results obtained with rufloxacin are consistent with its pharmacodynamic properties.

Adult↗
PubMed1991

Frequency and distribution of uropathogenic Escherichia coli adhesins: a clinical correlation over 2,000 cases.

In order to determine the pathogenic responsibility of Escherichia coli adhesins (ADHs) in urinary infections (UI), 2,000 different patients suffering different clinical urinary and male sexual gland infections were monitored. The ADHs were determined by agglutination techniques with human and guinea-pig red blood cells, Candida albicans and Saccharomyces cerevisiae cells and latex sensitized with GAL-GAL. In uncomplicated UIs, the possession of ADH is the main invasion mechanism for E. coli. The rate of E. coli ADH strains is very high (89%) in acute cases (727 of 818 cases: 310 of 362 cystitis; 104 of 113 recidivant cystitis; 120 of 126 pyelonephritis; 158 of 173 prostatitis, and 34 of 43 orchiepididymitis) and rare (10%) in asymptomatic or chronic cases (24 of 235 cases: 14 of 148 bacteriurias; 8 of 74 prostatitis, and 2 of 13 orchiepididymitis). A close relation is established between the presence of ADH and clinical symptoms. 90% (218 of 242) of acute cases with systemic symptoms are due to MR-type ADH strains, especially the P subtype. 71% (409 of 576) of acute cases with local symptoms are due to MS-type ADH strains. In complicated UIs the expression of ADH is not an essential condition for the invasion of the urinary apparatus. It has been strongly suggested that males are significantly more resistant to UI, both in the tract and parenchyma, than women. It can be deduced that the underlying disease is more liable to UI the lower the adherence level shown by isolated strains. Thus catheters, reflux and neurogenic bladder are, by far, more aggressive alterations than the prostatic adenoma, vesical tumor or lithiasis.

Adhesins, Escherichia coli↗
PubMed1986

Successful pregnancy in primary glomerular disease.

The course of 66 pregnancies was studied in 48 women with primary glomerular diseases. In all cases diagnoses were established by biopsy before pregnancy. They were: membranoproliferative glomerulonephritis in 16 patients, focal glomeruloesclerosis in 13, IgA nephropathy in 10, membranous nephropathy in seven and focal glomerulonephritis in two women. The clinical status of the nephropathy before conception was that 43 had only mild renal dysfunction, five had moderate renal insufficiency, serum creatinine (1.3 to 1.9 mg%), eight women had hypertension (150/100 mm Hg) and eight had nephrotic range proteinuria. Their clinical course was compared with a control group of 36 women with primary glomerular disease who did not become pregnant, and were matched for similar age, histological type, and status of nephropathy (renal function, blood pressure and proteinuria). After one year and at the end of the five year follow-up period, the incidence of hypertension, proteinuria, and renal failure was similar in the two groups. The fetal survival rate was 92%; 51 pregnancies ended in full-term delivery, with a mean birthweight of 3,242 +/- 320 g. There were seven pre-term deliveries (2,170 +/- 135 g), three small for gestational-age (2,340 +/- 135 g), two stillbirths and three spontaneous abortions. These patients had more pre-term deliveries (10.6%) and perinatal mortality (31%) than a normal population (5.5% and 9.6%, respectively). Blood pressure increased during pregnancy in 13 women; in 10 it was reversible, and in four it persisted after delivery. Ten gravidas developed increased proteinuria (reversible in six of them) and two others developed permanent impairment of renal function.(ABSTRACT TRUNCATED AT 250 WORDS)

Embryonic and Fetal Development↗
PubMed1984

Renal tuberculosis and hypertension: value of the renal vein renin ratio.

We applied the central renal vein renin ratios in a group of patients with unilateral renal tuberculosis and hypertension to see whether the diseased kidney was involved in the pathogenesis of the elevated blood pressure. Of 20 patients 11 were nephrectomized, 7 had positive renal vein renin ratios and normal peripheral plasma renin activity; only 2 kept their blood pressure in control without medication. From 5 without a positive index, only 1 kept his blood pressure in control without medicine 1 year after surgery. The renal vein renin ratio has to be interpreted in light of other parameters, such as blood pressure, peripheral renin--if high the more the chance of being significant--and global renal function. The renal vein renin ratio alone per se gives poor information on the pressor role of a unilateral tuberculous kidney.

Adult↗