Modulation of the immune response of Balb/c mice against Leishmania major by imuvert.

This study investigated the effect of Imuvert, a biological response modifier derived from Serratia marcescens, on the progression of Leishmania major infection in Balb/c mice. A single 100 micrograms Imuvert injection was significantly protective in Balb/c mice when challenged 28 days later in the footpad with 5 x 10(5) stationary phase L. major promastigotes. Intraperitoneal (i.p.) and intravenous (i.v.) immunization of mice with heat-killed stationary phase L. major promastigotes significantly reduced lesion development following challenge with L. major promastigotes. Subcutaneous (s.c.) immunization had no protective effect. A single 100 micrograms Imuvert injection significantly reduced lesion development in s.c. immunized mice, but had a lesser effect in mice immunized by i.p. and i.v. routes. Balb/c mice receiving four Imuvert injections 14, 7, 2 and 1 day prior to footpad challenge with L. major promastigotes were not protected, but rather displayed significant exacerbation of infection. Our results suggest the possibility that Imuvert could be useful in stimulating a protective response against L. major when given along with s.c. vaccine, a realistic route for vaccinating humans in contrast to either i.v. or i.p. routes. Since the protective response in Balb/c mice against L. major is dependent on the stimulation of Th1 cells, it is suggested that the observed adjuvant effect of Imuvert given with s.c. vaccine perhaps is due to changes in immunological responses in such a direction.

Computer-aided interpretation of ECG signals using polynomial regression methods.

Using polynomial regression methods this paper introduces a new approach to computer-aided interpretation of the ECG. An algorithm is presented for the identification and separation of ECG segments. The method of interpretation is efficient and its results are consistent and reliable.

Production and chemical studies of protease from Bacillus subtilis (SH-6) Egyptian strain.

Bacillus subtilis (SH-6) Egyptian strain, isolated from hides, gave the highest protease activity. Luxurious growth and protease production were obtained by the use of a medium containing 8% of potato starch, 0,1 M of ammonium phosphate as carbon and nitrogen sources. Results indicate that borate buffer exerted a deleterious effect on the protease production. Comparing citrate and phosphate buffers, it was found that citrate gave lower protease activity than phosphate. There is a positive response to higher concentrations of phosphate ions. From the above-mentioned medium protease was precipitated and purified. The dried preparation of the enzyme was tested for its chemical composition. It revealed the absence of residual carbohydrate. Tests for phosphorus, sulfur, ferric, zinc, manganese, magnesium, and calcium ions were positive. Amino acids present were: L-leucine, cysteine, Dl-alanine, L-arginine, L-tyrosine, L-aspargine, L-proline, glycine, Dl-valine, L-histidine, L-glutamic, L-lysine, L-aspartic, Dl-tryptophan, L-cystine, Dl-serine and Dl-phenylalanine. Quantitative analysis of the preparation was 0.52% of ash and 14% of nitrogen.