Dielectric measurements on live biological materials under magnetic resonance conditions

In the course of work on the interactions of electric and magnetic fields with both living and dead biological materials, it was noticed that certain published dielectrophoretic yield curves for biological cells showed unexplained deviations in the region of 2 kHz. Dielectrophoretic measurements made at frequencies and magnetic fields which satisfied the nuclear magnetic resonance conditions showed sharply resonant features. Dielectric measurements showed small, but sharp, resonances most easily seen in the dielectric loss curves which had a bandwidth of the order of one Hertz and presented at the frequencies which satisfied the magnetic resonance conditions for the ambient magnetic field. Resonances were found corresponding to the frequencies for electron spin resonance and nuclear magnetic resonance for¹H,³¹P,²³Na,³⁷Cl and³⁹K. The onset of these resonances occurs at the value of the steady magnetic field strength so that one quantum of magnetic flux (2.07×10^?15wb) would link a single biological cell or pair of cells, approximately 1 G (100μT) in the case of a 5-μm yeast cell. The effects of these magnetic resonance conditions on the mean generation time ofE. coli and on the reaction of the enzyme lysozyme with the substrateM. lysodeikticus cells are also shown.     

Chemical modification of alpha-chymotrypsin for obtaining high transesterification activity in low water organic media

Alpha-chymotrypsin was made more hydrophilic by modifying 11 (out of 16) ε-amino groups with pyromellitic dianhydride. The hydrophilic preparation was precipitated with n-propanol. This preparation gave significantly higher initial rates at the optimum a_w (127.51 nmol mg^?1 min^?1 in n-octane and 21.30 nmol mg^?1 min^?1 in acetonitrile at a_w=0.33) compared with the lyophilized preparation (53.50 nmol mg^?1 min^?1 in n-octane and 0.26 nmol mg^?1 min^?1 in acetonitrile at a_w=0.97). FT-IR showed that the precipitate of modified alpha-chymotrypsin has a higher content of alpha-helices and beta-sheets compared to the lyophilized powder.     

Modification of immune response by glycine in animals

Glycine (50, 100 and 300 mg/kg), administered daily for 10 days in rabbits challenged with typhoid 'H' antigen and sheep erythrocyte antigen, caused dose- dependent reduction of antibody titre. Inhibition of antibody titre observed with 300 mg/kg was comparable to immunosuppression observed with 1 mg/kg betamethasone.     

Population of goats related to climate in western India: an ecological assessment

Western India experiences arid to dry subhumid ecoclimate. Aridity increases from east to west to the Great Indian Desert or Thar Desert. The desert economy is animal based and goats are the most common livestock; density of goats increases with increase in aridity. There are large morphological variations in goats warranting the recognition of population differences throughout the region. The present investigations were therefore undertaken to see whether there are population differences and, if so, to establish the populations on a sound ecological basis. Eleven physical measurements of the animals were made in the fields of western India in a total of 518 animals (255 adults). Five populations were initially segregated by means of a scatter diagram. Population differences were confirmed by mathematical treatments using analysis of variance (one-way and two-way) and Students-Newman-Keuls test, which yields a critical comparison among means. Discriminant analysis was used to determine whether the goat populations differed significantly between the five climo-edaphic-vegetational zones. Each population was designated according to the locality having the greatest density as: POP1Ku, POP2Sa, POP3Jh, POP4Ga, POP5Pa. The five populations occurring in distinct climo-edaphic-vegetational zones or ecological niches in western India may be referred to as ecotypes.