PubMed Health⌕ Search

Biomedical subjects

M Vijayalakshmi

Publications and source records attributed to M Vijayalakshmi.

11 recordsLinked to original sources
PubMed2004

A preliminary report on effect of pulsed magnetic fields on fresh water fish (Labeo rohita) chromosomes.

Marine-life scientists around the world are already carrying out investigative trials to obtain higher yields under in-captive breeding conditions, on both edible varieties and ornamental fishes with optimal inputs. However, for such trials to succeed there is a need for genetic improvement. The idea that fish production can be enhanced by genetic manipulation is gaining acceptance, as there is a strong possibility that qualitative improvement of economically important traits can be achieved by identifying and utilizing more effective genotypes. In the present communication a tentative plan for genetic manipulation of fresh water fish using controlled, pulsed magnetic fields, is being discussed. Chromosome preparations of Labeo rohita were made using Colchicine-Methanol-Acetic acid air drying technique, using tissue from gills. The fish were exposed to Pulsed Magnetic Field (PMF)with intensity 0.2 Gauss, pulsing at 50 Hz frequency (sine wave) for 6 hours / day for a total period of 30 days inside specially designed magnetic field enclosures. The karyological investigations revealed no distinct difference between "test" and "control" groups.

Animals↗
PubMed2000

Studies on Alternaria sesami pathogenic to sesame.

Influence of pH on the growth of Alternaria sesami, its nutritional requirements and its ability to produce phytotoxic and antibacterial metabolites were tested. The isolate was cultured on Czapek-Dox broth and the culture filtrates were screened for phytotoxicity against seeds and seedlings of sesame. Chloroform extracts of the fungus exhibited antibacterial activity. Analysis of the culture filtrates for identifying toxins using chromatographic techniques revealed the presence of tenuazonic acid.

Alternaria↗
PubMed1998

Endotoxin removal with poly(ethyleneimine)-immobilized adsorbers: Sepharose 4B versus flat sheet and hollow fibre membranes.

Poly(ethyleneimine) was immobilized on poly(vinyl alcohol)-coated nylon flat sheet membranes, poly(vinyl alcohol) and poly(ethylenevinyl alcohol) hollow fibre membranes as well as Sepharose 4B. The resulting poly(ethyleneimine)-immobilized adsorbers were used for removal of E. coli derived endotoxin from buffers and bovine serum albumin solutions. The efficiency of poly(ethyleneimine) proved to be constant over a wide pH range, including phosphate buffered saline. The performance depended upon the matrix type employed: endotoxin clearance factors varied from 100 to 120,000 in protein-free solutions and 40 to 33,000 in solutions of bovine serum albumin using 6000 EU/ml as feed concentration. The best adsorber was the flat sheet membrane-immobilized poly(ethyleneimine), followed by the hollow fibre-immobilized poly(ethyleneimine) and poly(ethyleneimine)-Sepharose. The factors influencing endotoxin clearance were the mass transport (convective systems were superior to the diffusive system), the chemical composition and the surface structure of the underlying matrix.

Absorption↗
PubMed1995

Rapid one-step purification of goat immunoglobulins by immobilized metal ion affinity chromatography.

A rapid, single step purification of immunoglobulins from goat serum was achieved using immobilized metal ion affinity chromatography (IMAC) on a new high capacity gel, Novarose, coupled to tris(2-aminoethyl)amine (TREN) chelated with copper. When goat serum was adsorbed to this gel in buffer pH 7 at 11 cm/h (8.6 ml/h), the immunoglobulin fraction was recovered in a decreasing linear pH gradient at about pH 5.5. When the adsorption buffer was adjusted to pH 6.0 and the linear velocity increased to 110 cm/h (221 ml/h), an immunoglobulin fraction of greater than 95% homogeneity was obtained. Protein purity was assessed by silver-stained native and sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS PAGE). The capacity of the gel for immunoglobulins was 17 mg immunoglobulin/ml at the low flow rate with adsorption at pH 7 and 15 mg immunoglobulin/ml at the high flow rate with adsorption at pH 6. No problems of back pressure or gel compression were observed at the higher linear velocity. The mild elution pH, high flow rate, and synthetic nature of the ligand support make this new metal-chelating gel a powerful alternative to the use of other currently available commercial gels commonly used for immunoglobulin purification.

Animals↗
PubMed1994

Blood groups, ABH saliva secretion and colour vision deficiency in Hindu castes and religious groups of West Godavari, Andhra Pradesh, India.

The distribution of A1A2B0 and Rh(D) blood groups, ABH saliva secretion and red-green colour blindness among fourteen Hindu caste groups, besides Christian and Muslim populations of West Godavari District, Andhra Pradesh, India, is reported. All the Hindu castes except Brahmin, Kshatriya and Reddy exhibit relatively higher frequency of group B over group A. The subtyping of group A reveals that group A2 records an incidence ranging from 0.98% to 7.78%. The interpopulation chi-square tests for A1A2B0 blood group distribution indicate significant variation between several Hindu castes. The Vysya, Reddy and Adi Andhra castes not only differ from each other but also register significant variation from a majority of other populations. In the ABH saliva secretion also Vysya deviate from all other populations by recording the highest incidence (37.70%) of non-secretors, while the lowest frequency (19.98%) was observed among Kamma. The Rh(D) negative blood group is observed in all Hindu castes and religious groups with an incidence ranging from 1.04% in Vysya to 8.11% in Kamma. All the sixteen populations investigated exhibit prevalence of red-green colour blindness with a relatively higher frequency of deutan type over protan.

ABO Blood-Group System↗
PubMed1989

Cell surface interactions with metal chelates.

We have explored immobilized metal ion affinity adsorption as a means of discrimination between cells and to assess partially the types of interaction that might contribute to the adsorption of cells on the such adsorbents. Erythrocytes from different sources were adsorbed on immobilized iminodiacetic acid charged with Cu2+, Ni2+ or Zn2+. The affinity of the human erythrocytes for the immobilized metal ions follows the order Cu2+ greater than Ni2+ greater than Zn2+. The adsorption capacity of the rat erythrocytes decreased in the following order: Zn2+ greater than Ni2+ greater than Cu2+. Pre-saturation of the columns with imidazole lead to the recovery of over 90% of the cells applied on the columns. Enzymic removal of sialic acid residues from the surface of erythrocytes has no effect on the adsorption-elution profiles of these cells on affinity adsorbents. These findings suggest that histidine residues localized on the cell surface are involved in the cell binding to the adsorbent. This new separation principle could be expanded to other types of cell. It could be used as a diagnostic tool and for separation, as well as for probing cell surfaces.

Amino Acid Sequence↗
PubMed1978

ABO blood groups and fertility--with special reference to intrauterine selection due to materno-fetal incompatibility.

The purpose of the present investigation was to study whether there is differential fertility between different mating types of ABO blood group system. Selective force which is operating through maternal-fetal incompatibility has been observed in the differential fertility between compatible and incompatible mating groups in the present sample of 183 families of Visakhapatnam town of Andhra Pradesh,India. The differences in the mean numbers of pregnancies as well as living children between the two major mating groups, compatible and incompatible are significant. The fertility rates of O fathers and O mothers were significantly higher than those in matings in which neither parents belongs to O. The selection is operating to reduce the gene ratio of A and to increase the gene ratios of O and B in this sample.

ABO Blood-Group System↗
PubMedDate not supplied

Preliminary study of the metal binding site of an anti-DTPA-indium antibody by equilibrium binding immunoassays and immobilized metal ion affinity chromatography.

Creating metal coordination sites by modifying an existing enzyme or by eliciting antibodies against metal chelate haptens is of great interest in biotechnology to create enzyme catalysts with novel specificities. Here, we investigate the metal binding potential of a monoclonal antibody raised against a DTPA-In(III) hapten (mAb 734). We study its relative binding efficiency to metals of biological relevance by equilibrium binding immunoassays and immobilized metal ion affinity chromatography, two approaches which can give complementary information regarding composition and/or structure of the metal binding site(s). Fe(III), Fe(II), Cu(II), Mg(II), Ca(II), and Zn(II) binding was compared to In(III). All of them were shown to displace indium, but their affinity for mAb 734 decreased by 100-fold compared to indium. Competitive metal binding immunoassays between Zn(II) and In(III) revealed an unusual behavior by Zn(II) which remains to be explained. Moreover, IMAC allowed us to predict the metal binding amino acids involved in the antibody paratope. The antibody metal binding site was shown to contain at least two histidine residues in a cluster, and the presence of aspartic and glutamic acid as well as cysteine residues could not be excluded. Thus, simple competition studies allows us to obtain some partial information on the metal binding structural features of this anti-metal chelate antibody and to guide our screening of its catalytic potential.

Antibodies, Monoclonal↗