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Biomedical subjects

M Mitra

Publications and source records attributed to M Mitra.

At least 37 records · Page 2Linked to original sources

Deantigenation of human type B erythrocytes with Glycine max alpha-D-galactosidase.

Conversion of erythrocyte membrane B antigen to H antigen produces blood type O which is universally transfusable. If efficient large-scale production of enzymatically converted red blood cells is to be achieved, then optimal conditions for deantigenation must be determined. Cell suspension assays were used to study the blood group B activity of Glycine max (soybean) alpha-D-galactosidase on native human erythrocytes. The enzyme readily hydrolyzed the terminal alpha-D-galactosyl residue of the B antigen, converting it to H antigen. Optimal conditions for the enzymatic conversion of red cells with the Glycine enzyme are described. Normal cell morphology and function were maintained under optimal conditions.

ABO Blood-Group System↗

Phage-mediated conjugation in staphylococci as a means of transfer of drug-resistance.

Penicillin resistance plasmid was transferred from Staphylococcus aureus B4 (PcrKms, donor) to S. aureus ML351 (PcsKmr, recipient) by co-cultivation of the donor with the recipient in nutrient broth with or without the modifying effects of CaCl2 or sodium dodecyl sulfate. It was found that the transfer of drug-resistance occurred maximally between 6 and 18 hr postinoculation; however, addition of DNase (200 micrograms/ml) could totally prevent such a transfer up to 6 hr and significantly reduce it thereafter. Cell-free filtrate of the donor culture when mixed with the recipient was ineffective in bringing about the transfer of Pcr.

Conjugation, Genetic↗

Biology of Saryupari Brahmins of Chhattisgarh, central India.

In July-November, 1986, Saryupari Brahmins of Chhattisgarh (Central India) have been investigated for the distribution of ABO blood groups, Rh factor, ABH secretion, PTC taste sensitivity and seven morphological traits. The important findings in brief are as follows: 1. The frequency of O blood group is slightly dominant (38.91%) and gene frequency exhibit r > q > p pattern. Statistical analysis (D/sigma = 0.5447) show that the population is in genetic equilibrium. 2. Estimation of the expected rate of erythroblastosis foetalis occurred in this population is calculated to be 8-16 cases in every 10,000 pregnancies. 3. High incidence (53.82%) of non-secretors of ABH substances in saliva suggest that this group may belong to Caucasoid stock. 4. The ability to taste the chemical PTC has a high frequency (61.81%) in this group. 5. R/L type of handclasping (58.15%), leg folding (65.38%) and L/R type of arm folding (58.93%) is dominant. L-type of handedness (5.48%) is moderately high. 6. Tongue rollers (93.28%) and folders (53.77%) are more among them. 7. Free type of ear lobe (68.68%) is the common feature in this population. 8. The above observations were compared in details with other Brahmin populations reported from India with special reference to the descendant groups residing in Madhya Pradesh (Central India). Furthermore, the results obtained on growth studies, and dermatoglyphic studies (palm and sole) from our published literature were also included so as to have some idea on the genetical, behavioural, dermatoglyphic and growth norms of this group.

ABO Blood-Group System↗

Transmission of Sarcoptes scabiei from animal to man and its control.

Outbreak of Sarcoptes scabiei in animals spilling over to man in close association was observed in two adjacent villages, Fewgram and Nurpur in the district of Birbhum, West Bengal, from mid-November to mid-December, 1991. Nineteen goats and one calf who did not receive any treatment died of sarcoptic manage. All infected animals got cured with external application of deltamethrin, a synthetic pyrethroid and triazapentadiene. Human cases were treated successfully with benzene hexachloride (2%).

Adult↗

Purification and characterization of Phaseolus vulgaris alpha-D-galactosidase isozymes.

A highly purified preparation of alpha-D-galactosidase [E.C. 3.2.1.22] isozymes was obtained from Phaseolus vulgaris (pinto bean) seeds by extraction, salt precipitation, ion exchange, and affinity chromatography. The final preparation was homogeneous by SDS-PAGE but revealed isozymes of relative mass of 38.3 and 39.6 kDa. The N-terminal sequence for both isozymes was identical, LANGLAKT (one letter code for amino acids). Relative native molecular mass was estimated at 149.3 kDa by Sephacryl S-200 chromatography. Activity was unaffected by ionic strength at high enzyme concentrations, and was specific for alpha-D-galactoside conjugates. No protease or hemagglutinin activity was detected, and activity was stable at 4 degrees C. Studies with soluble oligosaccharides demonstrated high activity against the selected straight and branched-chain substrates. The enzyme was active against terminal alpha 1-3 galactosyl residues on human and rabbit erythrocyte membranes. Because of its activity against membrane glycoconjugates, these isozymes may have potential utility for modifying membrane epitopes on native erythrocytes.

Amino Acid Sequence↗

The polar phase response property of monopolar ECG voltages using a Computer-Aided Design and Drafting (CAD)-based data acquisition system.

The present paper discusses a Computer-Aided Design and Drafting (CAD) based data acquisition and polar phase response study of the ECG. The scalar ECG does not show vector properties although such properties are embedded in it. In the present paper the polar phase response property of monopolar chest lead (V1 to V6) ECG voltages has been studied. A software tool has been used to evaluate the relative phase response of ECG voltages. The data acquisition of monopolar ECG records of chest leads V1 to V6 from the chart recorder has been done with the help of the AutoCAD application package. The spin harmonic constituents of ECG voltages are evaluated at each harmonic plane and the polar phase responses are studied at each plane. Some interesting results have been observed in some typical cases which are discussed in the paper.

Algorithms↗

Sarcoptes scabiei in animals spreading to man.

An outbreak of Sarcoptes scabiei in animals was observed from mid-November 1991 to mid-December 1991 in two adjacent villages, Fewgram and Nurpur, in Birbhum District, West Bengal State, India, starting from goats to cattle, then to sheep and even to dogs. Nineteen goats and one cattle died of manage infection. The infection spread to man in the last week of December 1991, and affected forty-two human beings, tending and rearing animals. The animals treated with deltamenthrin (synthetic pyrethroid) and amitraz (triazapentadiene) were completely cured. In man, the disease seemed to be self-limited in some cases and 2% hexachlorobenzene was successfully used for treatment of the others. The outbreak was effectively controlled in March 1992.

Adult↗

Purification and characterization of N-acetyl-alpha-D-galactosaminidase from Gallus domesticus.

Exoglycosidases modify carbohydrate epitopes on glycoproteins and glycolipids. The N-acetyl-alpha-D-galactosaminidase from the domestic chicken, Gallus domesticus, is an important exoglycosidase which degrades the human blood group A epitope. This enzyme has never been demonstrably purified or thoroughly characterized. We have developed a technique to purify this enzyme to homogeneity. The isolated enzyme has a molecular weight of 49.1 kDa by SDS PAGE and 145.0 kDa by gel filtration. The enzyme is highly selective for PNP-N-acetyl-alpha-D-galactosaminide and is inactive against other low molecular weight substrates. The enzyme hydrolyzes the terminal N-acetyl-alpha-D-galactosaminide residues from blood group A2 erythrocytes. Protease activity is below detectable limits. The enzyme has a pH optima of 3.7, a pI of 8.15, is relatively unaffected by ionic strength, and is stable at 4 degrees C.

ABO Blood-Group System↗

Purification and characterization of a Coffea canephora alpha-D-galactosidase isozyme.

Exoglycosidases modify carbohydrate epitopes on glycoproteins and glycolipids. The alpha-D-galactosidase from Coffea canephora is an important exoglycosidase which degrades the human blood group B epitope. Although multiple isozymes have been described, they have never been demonstrably purified and thoroughly characterized. We have developed a technique to purify an isozyme to homogeneity. The isolated enzyme has a molecular weight of 36.7 kDa by SDS PAGE and 34.0 kDa by gel filtration. The isozyme is highly selective for alpha-D-galactosides and inactive against other low molecular weight substrates. It hydrolyzes the the terminal alpha-D-galactosyl residue from the blood group B epitope. Protease activity is below detectable limits. The isozyme has a broad pH optima at 6.3, a pl of 7.03, is unaffected by ionic strength, and is stable at 4 degrees C.

Amino Acids↗

A study of nine anthroposcopic traits among the three tribes of the Bastar District in Madhya Pradesh, India.

Nine anthroposcopic traits, namely palmar and plantar digital formulae, hand-clasping, armfolding, handedness, tongue rolling and folding, ear lobe attachment and legfolding have been studied in the three tribal populations--Murias, Bisonhorn Marias and Halbas--from the Bastar District in Madhya Pradesh (Central India). An attempt has been made to compare the results of the present study with other population groups of Central India.

Adolescent↗

Impact of massive doses of vitamin A on nutritional blindness in Bangladesh.

Impact of 6-monthly massive dosings of preschool-age children with oral vitamin A (VAC: 200,000 IU of oil soluble retinyl palmitate with 40 IU vitamin E) was evaluated in Bangladesh. In 100 sites, 11,889 households were visited and eyes of 22,335 children aged 3-71 mo were examined. About half the rural target population and less than 20% urban slum population were being reached. Risk of night blindness was halved for children reportedly given VAC, although 2.5% of the reportedly protected population were still night blind. There was no significant reduction in prevalence of Bitot's spot. Risk of corneal ulcers or keratomalacia (X3A/B) was 2.7 times higher in children not given VAC. Based on reported coverage, efficacy of protection against potentially blinding corneal lesions was 63%. For maximum impact on eye lesions, massive dosing with vitamin A at ideally less than 6-monthly intervals needs to be combined with other nutrition and health interventions.

Bangladesh↗

Landholding, wealth and risk of blinding malnutrition in rural Bangladeshi households.

The 1982-1983 Bangladesh nutritional blindness study visited 11,618 rural households and examined 18,660 preschool-age children in an effort to determine the prevalence and determinants of eye lesions and loss of sight due to vitamin A deficiency (xerophthalmia). Risk of xerophthalmia was significantly higher for children from households without any of the indicators of relative wealth used. Almost 80% of blind children from landless households, and even a very small garden reduced considerably the chances of a household having a xerophthalmic child. Poorer households with access to less than 0.3 acres land or no garden or without a tin roof, wristwatch, radio or cycle were at least twice as likely as their more fortunate neighbours to have a young child with any type of xerophthalmia. Taking account of such socio-environmental risk factor weightings would direct the scarce resources of intervention programmes to households and children who most need them.

Bangladesh↗

Postabortion insertions of the pleated membrane.

The pleated or intrauterine membrane (IUM) was designed to fit a range of uterine sizes and shapes and to adjust to transient changes resulting from uterine motility. The retention and contraceptive abilities of postabortion IUM insertions are analyzed in this study of 154 IUM insertions made within 3 days of treatment for an incomplete or inevitable abortion. Results indicate low 1-year net cumulative event rates for pregnancy (1.7 per 100 users), expulsion (7.2 per 100 users), and removal for bleeding and/or pain (3.9 per 100 users). These rates were similar to those reported in a study of interval insertions of the IUM; moreover, these results also compared favorably with corresponding rates of postabortion insertions reported in studies using other devices. Thus, the postabortion period is indicated as being an effective time for IUM insertion.

Abortion, Induced↗