1,720,971 research outputs found
[A year of blood cultures at the Associated Hospitals of Trieste: a critical evaluation of the clinico-laboratory approach to the patient with suspected bacteremia].
No full textThe authors evaluated the 2956 blood cultures performed in a multispecialist hospital in Trieste (Italy) during a whole year. A computer assisted analysis of the data pointed out that a single blood culture performed in a bacteremic patient could reveal 93\% of positivities, two blood cultures in the same day at least 96.6\% and three at least 98.3\%. Furthermore, in suspected bacteremic patients who received several blood cultures in subsequent days, the chance for a second day culture to reveal a bacteremia not pointed out in the first day was less than 4\%, while it was 0\% for the following days. These results assess the importance of a correct approach to the suspected bacteremic patient, and point out the usefulness of performing at most three blood cultures in the first day of clinical suspicion of bacteremia
Multivariate analysis of antibiograms for typing Pseudomonas aeruginosa.
No full textA method for typing Pseudomonas aeruginosa using antibiotic susceptibility patterns is presented, which allows recognition of clusters of the same strain among clinical isolates from different patients, thus indicating whether cross infection has occurred. An index of similarity (the euclidean or the oblique distance), which includes all the differences of disk zone sizes among isolates, is computed and then elaborated by a clustering algorithm that successively groups all the isolates in larger clusters. The results of clustering are presented as dendrograms, whose terminal branches are pruned down to a level below which differences are casual; isolates that still appear on a common branch are considered identical. The reliability of this technique for detecting nosocomial cross infections was assessed by comparing its results with that of serotyping and pyocin typing. Only 2 of 31 (6.4\%) clusters detected by multivariate analysis were not confirmed, while 4 of 33 (12.1\%) clusters were recognized by serotyping and pyocin typing, but not by multivariate analysis. In at least two instances the differences in susceptibility patterns were due to cytoplasmic R factors. The routine use of antibiogram data for typing purposes should be considered an essential part of nosocomial infection control
Trattamento "in vitro" di DNA plasmidico e selezione diretta dei mutanti in batteri trasformati
No full textCluster analysis of antibiotic susceptibility patterns of clinical isolates as a tool in nosocomial infection surveillance.
No full textHospital infections represent a major epidemiological problem. The first step in the detection of nosocomial infections consists in assessing the probability that two or more isolates from different patients are similar or different. Many methods are available for typing purposes. Among these, antibiotic susceptibility patterns do not need extra cost or extra work and are available "on line" every moment they are needed. A mathematical technique of elaboration is proposed for disk zone sizes, in order to assess the probability of two or more clinical isolates to be the same strain. Antibiograms performed according to Kirby-Bauer are evaluated detecting zone sizes by a computer controlled device and then submitted to cluster analysis. Similarity of strains is reported in a dendrogram, in which strains are successively fused. Strains that share a common susceptibility pattern are considered a "cluster". At last, epidemiological maps are constructed for each group of strains, in which all the isolates are reported, ordered for patients, plotted on the day the specimen was collected, drawn in a different shape according to the source of specimen, and shadowed by the pattern of its cluster. This method of reporting data directly allows to detect cross infections among patients and can be used as a first typing step before other more expensive procedures
Structure-Activity Relationship in the Mutagenic Effect of Chiral or Racemic 2-Bromo-2-propanamides on Salmonella typhimurium
No full textSome 2‐bromo‐propanamides were prepared and tested for direct mutagenicity in Salmonella typhimurium TA 100. Results confirm the mutagenic activity of 2‐bromo‐N‐benzyl‐propanamide and indicate that it is independent of enantiomeric configuration. A variation in the chemical structure, namely, the addition of a methyl group at the benzylic carbon, causes the four resulting diastereomers to be devoid of any activity. Conversely, some racemic ring‐substituted methoxy and/or hydroxy derivatives of the parent compound displayed mutagenic properties, causing an increase in the number of his+ revertants up to 524 per milligram per plate. Copyright © 1992 Wiley‐Liss, Inc., A Wiley Compan
Antitubercular activity of a new pyridinecarboxamidrazone compound alone and in combination with reference drugs, by MRA and in a macrophage model.
No full textRELATIONSHIP BETWEEN RSV INDUCED MEMBRANE ANTIGEN EXPRESSION AND PHENOTYPIC TRANSFORMATION
No full textAntimycobacterial activities of N1-[1-[3-aryl-1-(pyridin-2-,3-, or 4-yl)-3-oxo]propyl]-2-pyridinecarboxamidrazones.
No full textAre most ICU infections really nosocomial? A prospective observational cohort study in mechanically ventilated patients
No full textA prospective cohort study was undertaken with two end points: (i) to compare the 48 h time cut-off with the carrier state criterion for classifying infections, and (ii) to determine a time cut-off more in line with the carrier state concept. All patients admitted to the intensive care unit and expected to require mechanical ventilation for a period > or = 3 days were enrolled. Surveillance cultures of throat and rectum were obtained on admission and thereafter twice weekly to distinguish micro-organisms that were imported into the intensive care unit from those acquired during the stay in the unit. A total of 117 patients with median age of 61 years and median Simplified Acute Physiology Score II of 42, were included in the study. Of these patients, 48 (41%) developed a total of 74 infection episodes. Using the 48 h cut-off point, 80% of all infections were classified as ICU-acquired. According to the carrier state criterion, 44 infections (60%) were of primary endogenous development caused by micro-organisms imported into the intensive care unit. Seventeen secondary endogenous (23%) and 13 exogenous (17%) infections were caused by bacteria acquired in the unit. The carrier state classification allowed the transfer of 49% of infections from the ICU-acquired group into the import group. A time cut-off of nine days was found to identify ICU-acquired infections better than two days. These data suggest that monitoring of carriage of micro-organisms may be a more realistic approach to classify infections developing in the intensive care unit
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