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Biomedical subjects

A Califano

Publications and source records attributed to A Califano.

At least 19 recordsLinked to original sources

FLASH: a fast look-up algorithm for string homology.

A key issue in managing today's large amounts of genetic data is the availability of efficient, accurate, and selective techniques for detecting homologies (similarities) between newly discovered and already stored sequences. A common characteristic of today's most advanced algorithms, such as FASTA, BLAST, and BLAZE is the need to scan the contents of the entire database, in order to find one or more matches. This design decision results in either excessively long search times or, as is the case of BLAST, in a sharp trade-off between the achieved accuracy and the required amount of computation. The homology detection algorithm presented in this paper, on the other hand, is based on a probabilistic indexing framework. The algorithm requires minimal access to the database in order to determine matches. This minimal requirement is achieved by using the sequences of interest to generate a highly redundant number of very descriptive tuples; these tuples are subsequently used as indices in a table look-up paradigm. In addition to the description of the algorithm, theoretical and experimental results on the sensitivity and accuracy of the suggested approach are provided. The storage and computational requirements are described and the probability of correct matches and false alarms is derived. Sensitivity and accuracy are shown to be close to those of dynamic programming techniques. A prototype system has been implemented using the described ideas. It contains the full Swiss-Prot database rel 25 (10 MR) and the genome of E. Coli (2 MR). The system is currently being expanded to include the complete Genbank database.(ABSTRACT TRUNCATED AT 250 WORDS)

Algorithms

Effects of a new pyrazolo [3, 4-d]pyrimidine on growth and morphology of Candida albicans.

A new pyrazolo [3, 4-d]pyrimidine derivative was synthesized and its antifungal activity evaluated in vitro against mycelial and yeast cells of Candida albicans. The most striking ultrastructural changes following treatment with 10-30 micrograms/ml (mycelia) and 25-75 micrograms/ml (yeasts) consisted in the deterioration of the organelle membranes and in aberrant thickenings of the cell wall. The complete disorganization of the cytoplasmic structures seemed to be the final event.

Antifungal Agents

Preliminary results of a clinical trial relative to the use of rifamycin SV in the treatment of herpes zoster.

In a controlled clinical trial undertaken in ten Italian centres, rifamycin SV was compared to associations of various drugs such as erythromycin, aureomycin, multivitamin preparations, etc, in the treatment of herpes zoster. Up to now 144 patients, suffering from herpes zoster at different localizations, were divided into three groups and randomly given either rifamycin SV by intramuscular injection and topically, or rifamycin SV by injection only, or the routine treatment used at the particular centre in question. To evaluate the effectiveness of the treatments, the presence of subjective and objective symptoms was determined before treatment started and daily thereafter. The duration, in days, of the most important symptoms, such as erythema, vesicles, scabs and pain, was considered for this partial evaluation. All the above-mentioned symptoms constantly showed a shorter duration in the two groups treated with rifamycin SV compared to the group treated with other therapies, with differences as significant on statistical calculation as they were important on the level of a clinical evaluation of the disease's course.

Administration, Topical