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M C Goel

Publications and source records attributed to M C Goel.

33 records · Page 2Linked to original sources

Studies on activation and levels of haemolytic complement of buffalo (Bubalus bubalis). 1. Classical complement pathway.

Optimum conditions for haemolytic complement (HC) assay in buffalo serum were standardized. In all, 11 indicator systems of red blood cells (RBC) and haemolysins were investigated. Maximum HC CH50 titre was obtained with rabbit RBC sensitized with goat haemolysin. The effect of pH, Ca2+ and Mg2+ concentration, ionic strength, time and temperature were studied. Of all the variables, ionic strength influenced the HC activity most significantly. The standard system for titrating the HC consisted of rabbit RBC sensitized with goat haemolysin, sucrose-veronal buffer with pH 7.5, ionic strength 0.023 M and Ca2+ and Mg2+ concentrations 6 x 10(-4) and 2 x 10(-3) M, respectively. Incubation at 37 degrees C for 2 h gave highest haemolytic activity. With this protocol 5-7-fold higher HC activity was recorded than with prestandardized conditions. Levels of HC were determined in the sera of 98 buffaloes aged from 1 month to 12 years. The lowest mean CH50 units of 401 +/- 0.35 per ml were recorded in buffalo calves below 3 months of age. The mean HC levels increased with age, reaching peak values of 2349 +/- 62.25 CH50 units/ml in 2-3-year-old buffalo. Animals in the age group 5-12 years had significantly decreased (P less than 0.05) mean HC levels of 1545 +/- 68.94.

Animals↗

Effect of aflatoxin B1 on the delayed type hypersensitivity and phagocytic activity of reticuloendothelial system in chickens.

Efforts were made to see the effect of feeding aflatoxin B1 at 0.3 ppm level on various aspects of the immune system in chickens. The birds were fed aflatoxin B1 (AFB1) mixed ration from 0 to 6 weeks of age and thereafter normal feed was given up to 12 weeks of age. The delayed type hypersensitivity reaction of these birds was assessed by contact sensitivity to Dinitrofluorobenzene. The dietary AFB1 significantly suppressed the cell mediated immune response at all the three periods tested (30, 45 and 60 days of age). The toxin showed residual effect on immunity as the suppression of cell mediated immunity was maximum three days after the withdrawal of toxin from the feed. The effect of AFB1 on the phagocytic status of reticulo endothelial system (RES) was assessed by colloidal carbon clearance test at various intervals. The residual effect of toxin was observed on RES too as phagocytic index of AFB1 fed birds was significantly lowered up to 45 days of age.

Aflatoxin B1↗

Contact sensitivity to DNCB in normal and cell-mediated-immunity deficient chickens: in vivo detection and correlation with lymphocyte transformation and graft-versus-host reaction.

Optimum conditions for the contact sensitivity (CS) test using 2,4-dinitrochlorobenzene (DNCB) were sensitization with 0.25 ml of a DNCB solution (10 mg/ml) and challenge with one-tenth of this dose two weeks later. This produced reaction in terms of skin thickness which could be easily observed and measured. The cutaneous hypersensitivity developed slowly, reaching its maximum manifestation after 24 h of challenge and gradually declining thereafter. The development of a skin reaction was typical of delayed type hypersensitivity and was characterized histopathologically by congestion, oedema, mononuclear and heterophilic cell infiltration in the dermal layer and lymphocytic perivascular cuffing. The efficiency of the CS test was compared with that of the lymphocyte transformation (LT) test and graft-versus-host (GvH) reaction for monitoring cell-mediated immunity (CMI) in normal and CMI deficient chickens. CMI deficient chickens were prepared by neonatal thymectomy and inoculation of antithymocyte serum. The CMI response of deficient chickens was significantly less (p less than 0.01) as determined by all three tests. The percentage decrease in response to mount GvH, CS and LT was 88.9, 58.3 and 74.6, respectively. All the tests were found to be equally effective in assessing CMI response in chickens as determined by comparing the means of their performances.

Animals↗

Suppression of IgA synthesis in chickens.

Four different protocols were tested for the induction of IgA deficiency in chickens: (I) inoculation of anti-alpha intra-peritoneally (i.p.) on alternate days after hatching up to a period of three weeks; (II) bursectomy within 6 h and at 24 h after hatching; (III) in-ovo injection of anti-alpha on the 17th day of embryonation followed by bursectomy at 24 h of hatch and a single injection of anti-alpha i.p. on the day of hatching; (IV) as in III above but bursectomy within 6 h of hatch, followed by three further injections of anti-alpha on days 3, 10 and 34 after hatching. Treatment (I) produced temporary dysgammaglobulinemia during the period of treatment. Bursectomy at 24 h of hatch rendered 75% of the chicks IgA deficient up to four weeks of age. Early bursectomy within 6 h of hatch resulted in substantial improvement of IgA suppression. Such chicks, when tested at 4, 6 and 10 weeks of age, were found to be 81, 72 and 58.3% IgA deficient, respectively. With treatment (III) all the treated birds were IgA deficient at four weeks of age. However, as the birds grew older, IgA appeared in the serum so that at the age of 12 weeks only 27.3% were deficient. Treatment (IV) completely suppressed the IgA system of 13 out of 14 chickens. These chickens lacked both serum and secretory IgA as well as IgA-containing cells in their intestinal mucosa. Both IgG and IgM continued to be produced.

Age Factors↗

Normal profile of immunoglobulins in sera and tracheal washings of chickens.

Concentration and distribution of the three immunoglobulins in the sera and tracheal washings of a chicken population was studied. The mean IgM, IgG and IgA concentrations in serum were 1.35, 5.09 and 0.31 mg/ml, respectively. The distribution of IgM and IgG in birds irrespective of age was almost normal whereas that of IgA was skewed. All the three immunoglobulins were present in tracheal washings but the level of IgM was barely detectable. The IgG was predominant in the tracheal washings but higher IgA : IgG ratio compared to that of serum indicated local IgA production in the chicken respiratory tract.

Animals↗

New method for the isolation of membranes from Mycoplasma gallisepticum.

Mycoplasma gallisepticum lysed readily in carbonate bicarbonate buffer at pH 9.2 to 10.5. The hemagglutination titer of the lysates was 2- to 16-fold greater than a cell suspension at the same protein concentration in buffered saline. Membranes prepared from cells lysed by this method at pH 10 were relatively free from cytoplasmic contaminants as shown by electron microscopy of thin sections. The membranes retained their hemagglutination activity, gave reactions in immunodiffusion tests identical to those obtained by osmotic lysis and sonic treatment, and showed a similar pattern of protein bands by polyacrylamide disk electrophoresis. When inoculated into rabbits, the membranes gave rise to antibodies active in growth-, metabolic- and hemagglutination-inhibition tests. On the average, membranes obtained by lysis at pH 10 contained 44% of the original cell protein. The method is simple, giving high yields of membranes, and may be adaptable to other mycoplasmas.

Animals↗

Dissociation of Mycoplasma gallisepticum membranes with lithium diiodosalicylate and isolation of glycoprotein.

M. gallisepticum membranes were treated with 0.3M lithium diiodosalicylate (LIS) and, on average, 43% of the original membrane proteins were extracted. The extract contained particles with a sedimentation coefficient of 13S and some aggregated proteins. This LIS extract was immunogenic, stimulating the production of haemagglutination-inhibiting, growth-inhibiting and precipitating antibodies in rabbits. It was devoid of haemagglutinating (HA) activity for chicken erythrocytes but did inhibit the HA activity of membranes of M. gallisepticum. This inhibitory activity was destroyed by periodate and trypsin, but not by heat. By sedimentation equilibrium in a caesium chloride gradient, the LIS extract was separated into a lipoprotein-like and a glycoprotein fraction. The lipoprotein-like fraction contained the majority of the proteins present in the original extract, had HA activity and blocked antibody which inhibits haemagglutination. These activities were apparently due to the protein moiety, since they were not removed by extraction with n-butanol. The lipoprotein-like fraction behaved similarly to the unfractionated LIS extract in immunodiffusion tests and polyacrylamide gel electrophoresis, producing one periodic acid-Schiff positive band in the latter. The glycoprotein fraction consisted of about 66% carbohydrate and 33% protein. The sugar components were identified as glucose, galactose, glucosamine, galactosamine, glucuronic acid. The glycorprotein fraction did not possess HA but blocked the HA activity of M. gallisepticum membranes. In immunodiffusion it produced one faint precipitation band. The possible significance of glycoprotein in mycoplasma membranes has been discussed.

Antigens, Bacterial↗

Immunological response of chickens to Mycoplasma gallisepticum infection.

The cellular, humoral, and local immune responses of chickens to Mycoplasma gallisepticum infection were studied at weekly intervals for 10 weeks. A cellular response was indicated by significant leukocyte migration inhibition (LMI) was demonstrated as early as one week postinfection (PI), but the maximum LMI of 36.4% was observed at seven weeks PI. Induction of cellular response was further confirmed by positive-delayed type of hypersensitivity reaction, observed in all infected birds tested. The antibody response, as determined by the hemagglutination-inhibition (HI) test, was found to be provoked very early in infection, and the mean HI titer peaked seven weeks PI. A highly significant correlation (p less than 0.05) was found between LMI percentages and mean HI titers. In the infected chickens a significant elevation of mean serum immunoglobulin (Ig) G level was noted from the first week PI onwards; this correlated well with the rise of HI antibodies. There was no change in the serum IgA and IgM levels. A low level of M. gallisepticum-specific HI activity was detected in tracheal washings (TW) of infected birds from the third week PI onwards; the levels peaked six weeks PI. The IgA/IgG ratio in TW of infected chickens did not differ significantly from those of controls. The recovery of chickens as assessed by regression of lesions and disappearance of organisms from trachea coincided with peak LMI, maximum HI titers in serum and TW, and elevated levels of serum IgG.

Animals↗

Upper urinary tract stone analysis using X-ray diffraction: results from a tertiary referral centre in northern India.

BACKGROUND: The spectrum of urinary stone disease has changed considerably in India from the common childhood bladder stone to the more frequent upper tract calculi. We analysed the gravel retrieved from the upper urinary tract using X-ray diffraction analysis in an attempt to evaluate the composition of the stones. METHODS: We analysed 434 upper urinary tract calculi from May 1993 to June 1994 obtained endourologically, as well as by extracorporeal shock wave lithotripsy and open surgery. The stones were analysed using a Phillips compact X-ray diffractometer (PW1840). The PC-APD software was used for data collection and peak search. The phase matching was done by the software using the JCPDS reference database. RESULTS: Oxalate stones comprised 97% of the total stones with calcium oxalate monohydrate forming 90% and calcium oxalate dihydrate and mixed stones forming the remainder. Struvite stones were found in 1.4%, while uric acid and apatite stones were less than 1%. There were no cystine calculi. Seventy per cent of calcium oxalate monohydrate and 40% of calcium oxalate dihydrate stones were pure. All the struvite and apatite calculi were almost pure. Only 15% of staghorns did not consist of oxalate. Nine of the ten stones in children were of the calcium oxalate monohydrate variety. The stone composition in females was similar to that in males. CONCLUSIONS: X-ray diffraction data indicate that urinary stone disease in north India is different from that in the western world. Calcium oxalate monohydrate stones predominate. These stones are hard to break and have a different metabolic origin from those consisting of calcium oxalate dihydrate. These findings might help in selecting the most appropriate method of treatment in north India and they indicate directions in which further metabolic studies might be planned.

Adolescent↗