Showing papers by "University of Madras published in 1997"
TL;DR: This study demonstrates the selective response of plasma and haemocytic proPO to activation by different types of bacterial LPS tested and suggests that proPO system in both plasma andHaemocytes of P. viridis serves an important function in non-self recognition and host immune reactions.
Abstract: Phenoloxidase activity was detected in plasma and haemocytes of the marine mussel Perna viridis. This enzyme exists as a proenzyme, prophenoloxidase (proPO), in both these haemolymph fractions and could be activated in vitro by exogenous proteases (trypsin and alpha-chymotrypsin) and a detergent (sodium dodecyl sulphate). In addition, laminarin (a polymer of beta-1,3 glucan) and bacterial lipopolysaccharides (LPSa) effectively triggered proPO activation in these haemolymph fractions. The activation of proPO by non-self molecules was dependent upon calcium ions at a low concentration. This activation process appeared to involve a limited proteolysis, since serine protease inhibitors (soybean trypsin inhibitor, benzamidine or p-nitrophenyl-p'-guanidinobenzoate) suppressed conversion of proPO to the active enzyme. This study demonstrates the selective response of plasma and haemocytic proPO to activation by different types of bacterial LPS tested and suggests that proPO system in both plasma and haemocytes of P. viridis serves an important function in non-self recognition and host immune reactions.
127 citations
TL;DR: Serum bilirubin correlated positively with HDL cholesterol and inversely with triglycerides, VLDL cholesterol, LDL cholesterol, insulin, glucose and systolic blood pressure although these correlations were significant only in certain age-race-sex groups.
111 citations
TL;DR: A detailed analysis of the occurrence of the C-H...O hydrogen bonds in sheet regions of proteins has been presented and an inverse correlation is observed between the hydrogen-bond geometries involving the C(alpha)(i)-h...O=C and the N(i+1)-H...
Abstract: A detailed analysis of the occurrence of the C-H...O hydrogen bonds in sheet regions of proteins has been presented. 11 unique protein structures with resolution 1.3 A containing beta-sheets show a widespread presence of C-H...O hydrogen bonds. These have average C(alpha).O, CH...O distances and a C(alpha)-H...O angle of 3.29, 2.38 A and 143 degrees, respectively. As in the case of N-H...O hydrogen bonds, parallel and antiparallel beta-sheet regions show the same hydrogen-bond geometry. An inverse correlation is observed between the hydrogen-bond geometries involving the C(alpha)(i)-H...O=C and the N(i+1)-H...O=C suggesting that C-H...O hydrogen bonds may act as an additional stabilizing factor. The propensity of different amino-acid residues to form such hydrogen bonds varies and shows a clear preference for valine and threonine. C-H...O hydrogen bonds involving side chains also occur extensively in beta-sheet regions.
110 citations
TL;DR: In this paper, the effects of variation in concentrations of Ru(bpy)32+ and MV2+ on hydrogen photoproduction were investigated. And the efficiency of the sensitizers in hydrogen production was found to decrease in the order: Eosin Blue > Rose Bengal > Ru( bpy) 32+ > rhodamine B = acriflavin > fluorescein.
102 citations
TL;DR: In this article, the authors evaluated electrochemical surface pretreatment methods on the preparation of monomeric molybdate (VI)-modified glassy carbon electrode (GCE) in H2SO4.
Abstract: Evaluation of electrochemical surface pretreatment methods on the preparation of monomeric molybdate(VI)-modified glassy carbon electrode (GCE) in H2SO4 is studied. The results show that the cathod...
84 citations
Journal Article•
TL;DR: In this paper, the effect of alpha-tocopherol pretreatment on lipid peroxidation and antioxidant status in isoproterenol induced myocardial infarction was studied in rats.
Abstract: The effect of alpha-tocopherol pretreatment on lipid peroxidation and antioxidant status in isoproterenol induced myocardial infarction was studied in rats. Isoproterenol administered rats showed a significant increase in lipid peroxides in serum, heart and aorta. A significant increase in serum iron level with a significant decrease in iron binding capacity was also observed. The levels of antioxidants such as ceruloplasmin, glutathione and the activities of antioxidant enzymes such as superoxide dismutase, catalase, glutathione peroxidase, glutathione reductase and glutathione-S-transferase decreased significantly in isoproterenol administered rats when compared to control. The activity of Na+K+ATPase decreased significantly and the activity of Ca2+ATPase increased significantly in heart and aorta of isoproterenol administered rats. alpha-tocopherol pretreated rats maintained the levels of antioxidants, membrane bound enzymes and activities of antioxidant enzymes near normal, on isoproterenol administration, thus establishing its effect as an antioxidant.
82 citations
TL;DR: The fuzzy generalized connectedness, generalized fuzzy extremally disconnectedness and fuzzy generalized compactness are introduced and studied and various generalizations fuzzy continuous functions are defined.
81 citations
TL;DR: Sulphasalazine not only as causes morphological abnormalities in spermatozoa but may increase the chances of having congenitally abnormal offspring amongst men with IBD.
Abstract: The aims of the study were to ascertain whether patients have similar a fertility rate to the background population in Leicestershire and whether they have a similar rate of congenital malformations compared to the background population in Leicestershire. Over 1400 patients were invided to participate with an overall response rate of 81% after three successive mailings. The response rate was similar for both sexes and between the disease groups. The crude infertility rate for the group was 21%. The mean number of children for the whole group was 1.7 ± 1.3 but both men and women with Crohn's disease had significantly less children than would be expected, (men with Crohn's disease 1.5, women with Crohn's disease 1.2). There were 39 children (2% of overall births) with congenital abnormalities reported by patients with inflammatory bowel disease and in 29 cases the parents reported taking sulphasalazine (Table 3). Although this figure compares well with the 1.8% reported congenital abnormality rate for Leicestershire within the patient group in this study congenital malformations were significantly related to sulphasalazine use, z = 4.3, P < 0.0001. In conclusion sulphasalazine not only as causes morphological abnormalities in spermatozoa but may increase the chances of having congenitally abnormal offspring amongst men with IBD. The effects of other 5-aminosalacylic acids have yet to be studied in detail.
78 citations
TL;DR: The findings reviewed here emphasize awareness that chronic occupational exposure to low doses of endosulfan may result not only in behavioral abberations but in hazardous interaction with centrally acting drugs too.
74 citations
TL;DR: In this paper, the absorption and fluorescence spectra of different substituted acridinediones have been recorded in different solvents and the difference in the dipole moment between the ground and excited state has been obtained.
62 citations
Journal Article•
TL;DR: The results indicate that acrolein interferes with the antioxidant defense system of rat liver.
Abstract: Effect of acrolein (2.5 mg/kg body wt/day) on the rat liver antioxidant defense system was investigated. Following 45 days of acrolein exposure, the levels of glutathione, ascorbic acid and the activity of catalase were decreased whereas the activities of superoxide dismutase and glutathione peroxidase were increased. The increase in the level of thiobarbituric acid reactive substances in the acrolein treated rats showed oxidative damage. The results indicate that acrolein interferes with the antioxidant defense system of rat liver.
TL;DR: A small consanguineous family with this disorder was ascertained through the Institute of Basic Medical Sciences in Madras, India, and conditions such as rubella, prematurity, drug use during pregnancy, perinatal trauma, and meningitis were eliminated by history.
Abstract: Autosomal recessive non-syndromic hearing loss (ARNSHL) is the most common form of prelingual inherited hearing impairment. A small consanguineous family with this disorder was ascertained through the Institute of Basic Medical Sciences in Madras, India. Conditions such as rubella, prematurity, drug use during pregnancy, perinatal trauma, and meningitis were eliminated by history. Audiometry was performed to confirm severe-to-profound hearing impairment in affected persons. After excluding linkage to known DFNB genes, two genomic DNA pools, one from the affected persons and the other from their non-affected siblings and the parents, were used to screen 165 polymorphic markers evenly spaced across the autosomal human genome. Two regions showing homozygosity-by-descent in the affected siblings were identified on chromosomes 3q21.3-q25.2 and 19p13.3-p13.1, identifying one (or possibly both) as the site of a novel ARNSHL gene.
TL;DR: Observations suggest that the diseased stat e of adjuvant arthritis may be associated with augmented lipid peroxidation and the administration of the drug may exert its antiarthritic effect by retarding lipid per oxidation and causing a modulation in cellular antioxidant defence system.
Abstract: Oxygen derived free radicals are known to play an important role in the etiology of tissue injury in rheumatoid arthritis. The effect of milk extract of Semecarpus anacardium nuts at the dose level of 150 mg/kg body weight for 14 days on adjuvant arthritis was studied for gaining insight into the intrigue disease in relation to the lipid peroxidation and antioxidant defence system. Increased lipid peroxides' levels in both plasma and tissues (liver, kidney and heart) of adjuvant arthritis was significantly decreased by the administration of the drug. The antioxidant defence system studied in tissues of arthritic animals were altered significantly as evidenced by the decreased level of non-enzymatic antioxidants (GSH, vitamin E, vitamin C, NPSH and TSH) and enzymatic antioxidants (catalase and GPx except SOD). Administration of Semecarpus anacardium nut extract brings back the altered antioxidant defence components to near normal levels. These observations suggest that the diseased stat e of adjuvant arthritis may be associated with augmented lipid peroxidation and the administration of the drug may exert its antiarthritic effect by retarding lipid peroxidation and causing a modulation in cellular antioxidant defence system. (Mol Cell Biochem 175: 65–69, 1997)
TL;DR: The efficiency of resting egg production can be improved by employing semi-continuous culture method, which is 3.0 times more efficient than that from batch cultures.
TL;DR: In this article, XRD results confirm that the synthesized BaTiO 3 gel powders crystallize into tetragonal symmetry on heat treatment at 750 °C and show that the nature of the ferro-paraelectric transition depends on its crystallite size.
TL;DR: The coinoculation efficacy of the ectomycorrhizal fungi Laccaria laccata and Thelephora terrestris on Pinus patula seedlings was studied and compared to individual inoculation of these fungi in a nursery.
Abstract: The coinoculation efficacy of the ectomycorrhizal fungi Laccaria laccata and Thelephora terrestris on the growth and mycorrhizal development of Pinus patula seedlings was studied and compared to individual inoculation of these fungi in a nursery. The total number of mycorrhizas was higher in seedlings inoculated with the combined inoculum than with the individual inocula. The colonization by T. terrestris was higher than L. laccata when the seedlings were inoculated with the two fungi simultaneously. Coinoculation significantly increased the height and dry weight of the seedlings compared with individual inoculation, both in steam-sterilized and unsterilized soil.
TL;DR: In this paper, the oscillatory behavior of solutions of m th-order nonlinear neutral difference equations is investigated, and some examples which dwell upon the importance of their results are also included.
TL;DR: The intraperitoneal administration of gentamicin to rats is associated with an increased production of malondialdehyde, which is an end product of lipid peroxidation in the kidney, and the level of glutathione and the activity of three antioxidant systems were decreased.
Abstract: The intraperitoneal administration of gentamicin (100 mg kg[-1] day[-1]) to rats is associated with an increased production of malondialdehyde (MDA), which is an end product of lipid peroxidation in the kidney. The level of glutathione (GSH) and the activity of three antioxidant systems--superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPx)--were also decreased in the kidney. The liver, however, did not show any such alterations. Gentamicin (100 mg kg[-1] day[-1]) plus lipoic acid administration (25 mg kg[-1] day[-1]) by gastric intubation brought about a decrease in the degree of lipid peroxidation. An increase in the GSH level and in the activity of SOD, CAT and GPx was also observed. From these observations it can be concluded that administration of DL-alpha-lipoic acid prevents lipid peroxidation, which may, at least partly, play an important role in the injury cascade of gentamicin-induced nephrotoxicity.
TL;DR: On pretreatment with vitamin E the observed increased urinary activities of the enzymes and oxalate, histopathological changes and the deposition of CaOx crystals by administration of CsA in hyperoxaluria were prevented suggesting that vitamin E could be supplemented to prevent Cs a-induced membrane damage.
Abstract: The in vivo effect of cyclosporin A (CsA) on renal calcium oxalate (CaOx) crystal retention in experimental hyperoxaluric rats was investigated. Further, the effect of pretreatment of vitamin E on the
TL;DR: Significantly increased lysosomal membrane fragility as observed in arthritic condition was reduced in drug-treated animals and antiarthritic activity of the drug through its stabilizing action on lysOSomal membranes could be inferred from this study.
TL;DR: In this paper, a general photochemical synthesis of s-triazolo[3,4b]benzothiazoles from 4,5-disubstituted 1,2,4 triazole-3-thione is described.
Abstract: A general photochemical synthesis of s-triazolo[3,4-b]benzothiazoles from 4,5-disubstituted 1,2,4-triazole-3-thione is described. Steady photolysis, quantum yield determination, and laser flash pho...
TL;DR: The haemagglutination-inhibition assays revealed a unique specificity of serum agglutinin for acetylated aminosugars and that the presence of the acetyl group was essential for agglUTinin-ligand interaction.
TL;DR: In this paper, the nitrogen-bearing alloys (alloy 33 and alloy 24) and stainless steel type 316L were used in order to study the effect of alloying elements on electrochemical behavior and on the nature of passive film in seawater.
Abstract: The nitrogen-bearing alloys (alloy 33 and alloy 24) and stainless steel type 316L were used in this investigation in order to study the effect of alloying elements on electrochemical behavior and on the nature of passive film in seawater. Scanning electron microscopic studies were carried out to identify the pit morphology of the alloys. Surface analysis of the alloys by x-ray photoelectron spectroscopy after passivation showed that nitrogen and chromium are enriched at the surface of the passive film.
TL;DR: The administration of Semecarpus anacardium nut extract caused a significant decrease in the activity of glycolytic enzymes and an increase in gluconeogenic enzymes' activities to near normal values in drug-treated animals.
TL;DR: Assay of carbohydrate-metabolizing enzymes clearly indicated that the vanadyl complex activates the glycolysis, glycogenesis and depresses the glycogenolysis and gluconeogenesis in diabetic rats, suggesting its insulin-like nature.
Abstract: Blood glucose levels of rats with alloxan-induced diabetes dropped from hyperglycemic levels to hypoglycemic ones after treatment with bis-salicylidine ethylenediiminato oxovanadium (IV) complex for a period of 30 days. However, the diabetic condition reappeared after withdrawal of the vanadyl complex. Assay of carbohydrate-metabolizing enzymes clearly indicated that the vanadyl complex activates the glycolysis, glycogenesis and depresses the glycogenolysis and gluconeogenesis in diabetic rats, suggesting its insulin-like nature. The optimum dose of bissalicylidine ethylenediiminato oxovanadium (IV) complex to produce the normoglycemic level in the diabetic rats was 7.5mg of vanadium/kg body wt/day.
TL;DR: Biotechnique for programmed freezing of the spermatozoa of the edible mud crab Scylla serrata and the procedures for assessing viability of the frozen-thawed spermatoza are described and the limitations of the dye exclusion method as an indicator of sperm viability are discussed.
Abstract: Biotechnique for programmed freezing of the spermatozoa of the edible mud crab Scylla serrata and the procedures for assessing viability of the frozen-thawed spermatozoa are described. Free spermatozoa recovered from spermathecae and those released from the spermatophores were subjected to cryoprotectant treatment at different physiological temperatures (30°C, 23°C, 15°C), frozen to subzero temperatures in a rate-controlled programmable freezer Kryo 10/1.7 and subsequently plunged into liquid nitrogen. Post-thaw viability, after 8 hr of storage at −196°C, was assessed by artificial induction of acrosome reaction using divalent cation ionophore A23187. Hypo/hyperosmotic sensitivity tests were used to assess the membrane integrity of the spermatozoa before and after cryopreservation experiments. Viability tests using dye exclusion methods were discontinued owing to variations in incorporation of different stains into the spermatozoa. The limitations of the dye exclusion method as an indicator of sperm viability are discussed. Dimethyl sulfoxide, ethylene glycol and glycerol offered cryoprotection at concentrations ranging from 5% to 15% v/v. Post-thaw survival was highest (52%) with 12.5% glycerol at a cooling rate of −5°C/min. J. Exp. Zool. 277:326–336, 1997. © 1997 Wiley-Liss, Inc.
TL;DR: The exposure time to chlorine required for 100% mortality of B. striatulus is much lower than that reported for some other common fouling mussels, and reduction in physiological activities of mussels was strongly correlated with the concentration of chlorine.
28 Jul 1997
TL;DR: The reduction of AFB 1 induced hepatotoxicity provides an in vivo evidence for the drug to be regarded as a potent and valuable chemotherapeutic agent against hepatocarcinoma.
Abstract: Aflatoxin B 1 (AFB 1) induced rat liver cancer is a well studied system of hepatocarcinogenesis. The present investigation aims at assessing the effect of Semecarpus anacardium nut milk extract on AFB 1 mediated hepatocellular carcinoma. This extract was administered orally (200 mg/kg body weight/day) for 14 days to hepatocarcinoma bearing rats. The level of lipid peroxides and antioxidant enzymes’ activity were determined in liver and kidney homogenates. Marked increase in lipid peroxide levels and a concomitant decrease in enzymic antioxidant levels were observed in carcinoma induced rats, while drug treatment reversed the conditions to near normal levels. The reduction of AFB 1 induced hepatotoxicity provides an in vivo evidence for the drug to be regarded as a potent and valuable chemotherapeutic agent against hepatocarcinoma.
TL;DR: In this paper, a poor correlation is observed between experimental and theoretical kq values calculated using kd from the Debye expression, and the observed quenching constants are in good agreement with the kq value calculated using Kd = 3.7 × 1010 M-1 s-1, which was obtained from Smoluchowski expression and ΔG⧧ from the Rehm−Weller expression.
Abstract: The excited singlet state of 2,4,6-triphenylpyrylium ion reacts with benzene derivatives by the electron transfer mechanism, and the radical yield was measured using the flash photolysis technique. A poor correlation is observed between experimental and theoretical kq values calculated using kd from the Debye expression. The observed quenching constants are in good agreement with the kq values calculated using kd = 3.7 × 1010 M-1 s-1, which is obtained from Smoluchowski expression and ΔG⧧ from the Rehm−Weller expression. The back electron transfer rate constant is determined from the quantum yield of the radical. Marcus inverted region is observed for the back electron transfer rate constants in the highly exothermic region of ΔGb.