Detection of antibiotic resistance in Enterococcus sp. Comparison of GPS-TA (BioMérieux-Vitek), Uniscept MIC-3 (bioMérieux-Vitek) and conventional methods

BACKGROUND: The treatment of severe enterococcus infections requires synergism of a beta-lactamic or glycopeptide and a aminoglycoside, but when resistance to first one or high-level resistance to aminoglycosides are present, synergism would be lost. We compared the adequacy of two commercially available systems to detect antibiotic resistance. METHODS: We studied 158 isolates of Enterococcus sp., with high-level resistance to gentamicin (40 isolates) and streptomycin (89 isolates), resistance to ciprofloxacin (34 isolates), resistance to ampicillin (7 isolates) and with intermediate susceptibility to vancomycin (3 isolates). No one was beta-lactamase producer by Cefinase disk method. We use disk diffusion as reference technique to detect high-level streptomycin resistance. The susceptibility to the remainder antibiotics was studied by agar dilution method, according to NCCLS. We studied the accuracy of GPS-TA cards and Uniscept MIC-3 in relation to the degree of agreement with conventional means, following FDA criteria. RESULTS: Essential agreement for MIC was less than 90 with MIC-3 for ampicillin (81.5%) and ciprofloxacin (71.3%). Categorical agreement rate was less than 90% (76.4%) and major error rate was higher than 3% (10.9%) with the use of MIC-3 for ciprofloxacin. Very major errors for ampicillin, vancomycin and ciprofloxacin were not produced by any system. The very major error rates for high level resistance to gentamicin and streptomycin with GPS-TA card were 5 and 15.7%, respectively. CONCLUSIONS: We do not recommend the use of the Uniscept MIC-3 panel with visual reading to detect susceptibility to ciprofloxacin. Detection of high levels of aminoglucoside resistance by GPS-TA card should be supplemented with conventional techniques because of the high rate of major error. Due to the low number of strains that have been studied, we can not assure the suitability of these systems to detect ampicillin or vancomycin resistance.     

Dyslipemia in a population with a high rate of cardiovascular mortality

The activity of N-acetyltransferase (NAT) and catalase was measured in the tissues of placenta, full venous blood and full umbilical cord blood in 141 complicated pregnancies. The control group consisted of 34 physiological pregnancies. The enzymes activity was marked by use of biochemical methods. It has been shown that NAT and catalase is the most active in the group of physiological pregnancies. The decrease of NAT and catalase in venous and umbilical cord blood is correlated with the decrease of the activity these enzymes in placenta.     

Liver glutathione content and glutathione-dependent enzymes of two species of freshwater fish as bioindicators of chemical pollution

Glutathione content and glutathione-dependent enzymes were measured in the liver of two fish species, gudgeon (Gobio gobio) and roach (Rutilus arcasii), from the river Bernesga (Spain) caught downstream and upstream of the waste site of several chemical industries. Animals from contaminated sites display a reduced glutathione concentration and a tendency to the decrease of glutathione S-transferase activity. Glutathione peroxidase activity was significantly elevated only in the liver of Gobio gobio and glutathione reductase activity in that of Rutilus arcasii. Our data indicate that the glutathione system constitutes a sensitive biochemical indicator of chemical pollution. Relative changes of glutathione and glutathione-dependent enzymes in both fish species suggest a different susceptibility to toxins.     

A new method forin-situ measurement of electrical resistivity of reinforced concrete

A new method is described for thein-situ measurement of electrical resistivity of concrete structures. The method is based on the early work of J. Newman who calculated the electrolyte resistivity between a disk and a counter electrode located at infinity. This method has the advantage compared with Wenner's of using a single small electrode for the measurements. In this paper, results are presented comparing this method with Wenner's and with results carried out using a conductivity cell in electrolytes. Finally, values of resistivity are compared to corrosion intensity, and a threshold for active corrosion is suggested.

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Résumé On décrit une nouvelle méthode de mesure de la résistivité électrique du béton dont la technique est basée sur un travail ancien de J. Newman qui avait calculé la résistivité entre un disque et une électrode auxiliaire placée à l'infini. Comparée à la méthode de Wenner, cette méthode présente l'avantage de n'utiliser, pour les mesures, qu'une petite électrode. Dans cet article, on présente les résultats de la comparaison établie avec la méthode de Wenner et avec les résultats obtenus avec une cellule de conductivité placée dans les électrolytes. Enfin, on compare les valeurs de la résistivité du béton avec celles de l'intensité de la corrosion et on suggère un seuil de corrosion active.

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Editorial note Camen Andrade and Maria-Cruz Alonso are working at the Instituto Eduardo de Torroja which is a RILEM Titular Member. Dr. Andrade, who was the 1986 RILEM Medallist, have had all these years great responsibilities within RILEM. Chairlady of the Advisory Technical Committee until 1993, she is now a member of the Coordinating Committee. She is active in 116-PCD Technical Committee on Permeability of Concrete as a Criterion of its Durability and has been appointed chairdlady of 154-EMC Technical Committee on Electrochemical Techniques for Measuring Metallic Corrosion. Carmen Andrade has been appointed RILEM Fellow in 1995.     

Noise and machine failures: determining factors in the acceptance and behavior of O2 concentrator. The Asturias project

Whether a sulfonylurea may be used together with insulin for treating NIDDM has been controversial. One view, based on older studies, has been that the additional benefit is too small or the level of glucose control achieved usually too poor to recommend this method. More recent studies of a more specific way of combining a sulfonylurea with insulin are more supportive. When a single injection of insulin taken in the evening is added to a sulfonylurea at the time of secondary failure of the sulfonylurea alone, glycemic control is quite simply and consistently restored to acceptable levels. At this time in the natural history of NIDDM, evening insulin combined therapy is more effective than a single injection of insulin alone, and just as effective as a more complex multiple-injection regimen without an oral agent. A recent multicenter trial of a new sulfonylurea, glimepiride, in combination with a single injection of 70/30 insulin before dinner has confirmed that this approach is safe and more consistently effective than insulin alone for obese patients beginning insulin in a setting resembling clinical practice. The available evidence suggests this form of combined therapy is suitable for routine use.     

Renopancreatic transplant. Urologic complications

OBJECTIVE: Retrospective study of urological complications in our series of reno-pancreatic transplants. MATERIAL AND METHODS: Between February 1983 and May 1994 our group has conducted 93 RPT, 80 of which, mean age 36 +/- 6 years (24-54 years), are studied in this paper: 57 male and 23 female with an average time in dialysis of 20 +/- 15 months (0-84 months) and diabetes evolution of 21 +/- 5 years (11-37 years). RESULTS: Actuarial annual survival of patient, renal graft and pancreatic graft has been 85%, 79% and 74% respectively. Haematuria: 25% incidence, with graft pancreatitis etiology in 16 cases, rejection in 8 and urinary fistula in 6. Urinary infection: 85% incidence, symptomatic in 23 patients (29%) and asymptomatic in the remaining cases. Dysuria, urethritis and urethral stenosis: 14 patients, all male, most with both conditions associated. Reconversion of pancreatic exocrine secretion by intestinal route was performed in 7 patients. Urinary fistula: secondary to surgery in 9 cases and rejection in 4. Etiology of one case remained unknown. In 4 cases it was resolved with conservative treatment, and with surgical correction in 8. One patient required pancreatic transplantectomy and one patient died of AMI. CONCLUSIONS: Urological complication in RPT account for a significant morbidity, urinary fistula being the one with greater repercussion on the patient and pancreatic graft survival.     

Uncertainty Matters: Computer Models at the Science–Policy Interface

The use of computer models offers a general and flexible framework that can help to deal with some of the complexities and difficulties associated with the development of water management plans as prescribed by the Water Framework Directive. However, despite the advantages modelling presents, the integration of information derived from models into policy is far away from being trivial or the norm. Part of the difficulties of this integration is rooted in the lack of confidence policy makers have on the incorporation of modelling information into policy formulation. In this paper we examine the reasons for this apparent lack of confidence and explore how some tools, presently in use, address this problem. We conclude that public confidence in models is highly dependent on the way uncertainties are addressed and suggest possible directions of action to improve the current situation. Four real case studies illustrate how computer models have been used in The Netherlands for carrying out management plans at regional and national scale. We suggest that the solution to integrate modelling information into policy formulation lies on both the modelling and the policy-making communities.     

Microbiologic depuration of Anadara tuberculosa (Mollusca: Arcidae)

In Costa Rica the mollusk Anadara tuberculosa represents a risk for human health due to the contamination of the growing waters and the fact that its is consumed raw. The families depending on the income obtained through commercialization of these animals have a low education and economic status. Therefore, it is of great importance to develop and evaluate simple methods of depuration that could be easily used by these families to make these mollusks safe for consumption. Bottles containing 11 of saline solution (25g/l) were prepared in duplicates to test the bactericidal effect of acetic acid. The solution in each bottle was adjusted to ph 4.5, 5.0 or 5.5 or held at ph of 7.0 or 8.0 for the controls. The solution in each bottle was then inoculated with approximately 1 X 104 cfu/ml of coliforms. Counts of coliforms were determined for each bottle 0, 1, 2, 4 and 8 hours after inoculation. For the depuration studies, specimens with diameters ranging from 4.0 to 4.5 cm were collected from a harvester at the estuary of Puntarenas, Gulf of Nicoya. Fifty specimens each were depurated in separate tanks containing 25 1 of oxygenated saline solution adjusted with acetic acid to an initial ph of 4.5 (treatment) or non adjusted ph of 8.0 (control). Counts of Enterobacteriaceae were determined, in duplicates, every 12 hr for 48 hr. An additional fifty animals were depurated using the defined method and tested to determine if they met international standards of microbiological quality for aerobic plate count, Enterobacteriaceae count, Escherichia coli count and presence of Salmonella. A sensory evaluation using a triangle test was performed to compare a typical dish prepared with depurated or non-depurated animals. A significant coliform reduction was determined in a saline solution (25 g/l) at a pH range of 4.5 to 5.5. This reduction, during 8 hr, was higher in the acid treatments compared to the controls. During depuration, the elimination of Enterobacteriaceae bacteria was faster when acetic was used (initial ph = 4.5) than when it was not. This elimination was more important the first 24 hr, time defined as adequate for the application of the method. The method has the advantage of transforming the bivalve in a product that is safe for human consumption, since it guarantees that the international standards of microbiological quality, for raw and depurated mollusks, are reached. On the other hand, the sensory qualities of a typical dish prepared with depurated animals are not affected by the method, which can be easily implemented and applied by the people that work in the extraction of this mollusk.