Showing papers by "University of Madras published in 2007"
TL;DR: In vitro antibacterial activities of drugs capped Au nanoparticles (Au@drugs) were investigated and suggest that gold nanoparticles could act as an effective drug carrier in drug delivery system.
268 citations
TL;DR: Findings suggest that M. koenigii treatment exerts a therapeutic protective nature in diabetes by decreasing oxidative stress and pancreatic beta-cell damage.
236 citations
TL;DR: This review mainly focuses on the different methodologies employed recently for the optimum production of β-carotene from Dunaliella species.
Abstract: Halotolerant microalga Dunaliella, which is exploited for the production of dried biomass or cell extract, is used as a medicinal food. With the advancement in this field in recent years, the production of bio-organic compounds such as β-carotene is established in many countries. Large-scale production of β-carotene is controlled by numerous stress factors like high light intensity, high salinity, temperature and availability of nutrients. The state-of-the-art strategies in industries in closed systems under new set of inductive factors will additionally promote the ease of commercial production of β-carotene. This review mainly focuses on the different methodologies employed recently for the optimum production of β-carotene from Dunaliella species.
235 citations
TL;DR: The results from the present study indicate that silymarin exhibits good hepatoprotective and antioxidant potential against diethylnitrosamine induced hepatocellular damage in rats.
215 citations
TL;DR: This study demonstrates that GSP has a significant effect in the protection of heart against MI induced by ISO and believes that pretreatment with GSP may contribute to developing novel strategies in the prevention and treatment of cardiotoxic effects of elevated levels of catecholamine.
190 citations
TL;DR: To identify the sources and quality of groundwater, water samples from 47 bore wells were collected and were analysed for major ions and trace metals and reveal that the groundwater in many places is contaminated by higher concentrations of NO3, Cl, PO4 and Fe.
Abstract: The Lower Ponnaiyar River Basin forms an important groundwater province in South India constituted by Tertiary formations dominated by sandstones and overlain by alluvium. The region enjoyed artesian conditions 50 years back but at present frequent failure of monsoon and over exploitation is threatening the aquifer. Further, extensive agricultural and industrial activities and urbanization has resulted in the increase in demand and contamination of the aquifer. To identify the sources and quality of groundwater, water samples from 47 bore wells were collected in an area of 154 km2 and were analysed for major ions and trace metals. The results reveal that the groundwater in many places is contaminated by higher concentrations of NO3, Cl, PO4 and Fe. Four major hydrochemical facies Ca–Mg–Cl, Na–Cl, Ca–HCO3 and Na–HCO3 were identified using Piper trilinear diagram. Salinity, sodium adsorption ratio, and sodium percentage indicate that most of the groundwater samples are not suitable for irrigation as well as for domestic purposes and far from drinking water standards. The most serious pollution threat to groundwater is from nitrate ions, which are associated with sewage and fertilizers application. The present state of the quality of the lower part of Ponnaiyar River Basin is of great concern and the higher concentration of toxic metals (Fe and Ni) may entail various health hazards.
151 citations
TL;DR: Recent reports on the bilirubin clearance effect of Chinese herbal tea Yin Zhi Huang or its active ingredient 6,7-dimethylesculetin, in jaundice are very exciting and warrant investigations on its, possible, ameliorative effects in lantana intoxicated animals.
Abstract: Lantana (Lantana camara Linn) is a noxious weed that grows in many tropical and subtropical parts of the world. Ingestion of lantana foliage by grazing animals causes cholestasis and hepatotoxicity. Both ruminants and nonruminant animals such as guinea pigs, rabbits, and female rats are susceptible to the hepatotoxic action of lantana toxins. The hepatotoxins are pentacyclic triterpenoids called lantadenes. Molecular structure of lantadenes has been determined. Green unripe fruits of the plant are toxic to humans. Lantana spp. exert allelopathic action on the neighboring vegetation. The allelochemicals have been identified as phenolics, with umbelliferone, methylcoumarin, and salicylic acid being the most phytotoxic. In addition to phenolics, a recent report indicates lantadene A and B as more potent allelochemicals. Management of lantana toxicosis in animals is achieved by drenching with activated charcoal and supportive therapy. Recent reports on the bilirubin clearance effect of Chinese herbal tea Yin Zhi Huang (decoction of the plant Yin Chin, Artemisia capillaries, and three other herbs) or its active ingredient 6,7-dimethylesculetin, in jaundice are very exciting and warrant investigations on its, possible, ameliorative effects in lantana intoxicated animals. Research is being conducted on new drug discovery based on natural products in different parts of the lantana plant.
145 citations
TL;DR: An amperometric sensor for hydrogen peroxide was developed using multiwalled carbon nanotubes (MWCNTs) covalently immobilized with thionine via a carbodiimide reaction.
136 citations
TL;DR: Kalpaamruthaa (KA), a modified indigenous Siddha formulation constitutes Semecarpus anacardium nut milk extract, Emblica officinalis and honey.
Abstract: Kalpaamruthaa (KA), a modified indigenous Siddha formulation constitutes Semecarpus anacardium nut milk extract, Emblica officinalis and honey. KA is evaluated for its behavioral and toxicological effects and also its consequence on biochemical and histological variations. Acute and subacute toxicity studies with KA were done on Wistar Albino rats. During acute toxicity study (72 hr), there were no any adverse effects found in the general behavior and mortality at any dose level given (50–2000 mg/kg b.wt.). In subacute toxicity study (30 days) KA (50, 100, 250 and 500 mg/kg b.wt.) did not cause any changes in hematological and biochemical parameters with the exception of a transient rise in hemoglobin, leukocyte count, free fatty acid, plasma and urine creatinine and a significant decrease in blood glucose, total cholesterol, triglyceride and phospholipid levels. The changes observed are significant only at the highest dosage of 500 mg/kg b.wt. Further, histopathological examination of vital organs showed normal architecture suggesting no morphological disturbances; it can be considered that KA is safe and non toxic.
126 citations
TL;DR: Findings indicate the protective effect of α‐mangostin on lipid peroxidation and antioxidant tissue defense system during ISO‐induced myocardial infarction in rats.
Abstract: Increased oxidative stress and antioxidant deficit have been suggested to play a major role in isoproterenol-induced myocardial infarction. The present study was designed to evaluate the effect of alpha-mangostin on the antioxidant defense system and lipid peroxidation against isoproterenol-induced myocardial infarction in rats. Induction of rats with ISO (150 mg/kg body weight, ip) for 2 days resulted in a marked elevation in lipid peroxidation, serum marker enzymes (LDH, CPK, GOT, and GPT) and a significant decrease in the activities of endogenous antioxidants (SOD, CAT, GPx, GST, and GSH). Pre-treatment with alpha-mangostin (200 mg/kg of body weight per day) orally for 6 days prior to the ISO administration and 2 days along with ISO administration significantly attenuated these changes when compared to the individual treatment groups. These findings indicate the protective effect of alpha-mangostin on lipid peroxidation and antioxidant tissue defense system during ISO-induced myocardial infarction in rats.
116 citations
TL;DR: Comparison of acid leachable trace metals indicates increase in concentrations in the study area and the sediments act as a sink for trace metals contributed from multiple sources.
TL;DR: The electrocatalytic oxidation of hydrazine by MnHCF modified graphite-wax composite electrode has been investigated in an attempt to develop a new sensor for its determination and it was found that the mediator catalyzed the oxidation of Hydrazine.
TL;DR: It could be concluded that T. arjuna acts as an gastroprotective agent probably due to its free radical scavenging activity and cytoprotective nature.
TL;DR: Oral administration of the crude and purified compound from the leaves of P. pinnata effectively inhibited WSSV pathogenesis and reduced the mortality of infected shrimp.
Journal Article•
TL;DR: Silymarin could be developed as a promising chemotherapeutic adjuvant for the treatment of liver cancer after significantly attenuated the alteration of these markers and decreased the levels of MDA-DNA adduct formation.
Abstract: AIM To study the effect of silymarin on the levels of tumor markers and MDA (malondialdehyde)-DNA adduct formation during N-nitrosodiethylamine induced hepatocellular carcinoma in male Wistar albino rats. METHODS The levels of AFP, CEA and activities of liver marker enzymes in serum, MDA-DNA immunohistochemistry were done according to standard procedures in the control and experimental groups of rats. RESULTS Hepatocellular carcinoma was evidenced from significant (p < 0.05) increases of alpha-fetoprotein, carcinoembryonic antigen, aspartate aminotransferase, alanine aminotransferase, alkaline phosphatase, acid phosphatase, lactate dehydrogenase, gamma-glutamyltransferase and 5'-nucleotidase in serum and increased MDA-DNA adducts were also observed in the tissue sections of hepatocellular carcinoma. Silymarin treatment significantly attenuated the alteration of these markers and decreased the levels of MDA-DNA adduct formation. CONCLUSION Silymarin could be developed as a promising chemotherapeutic adjuvant for the treatment of liver cancer.
TL;DR: The above data shows that the anticancer effect of quercetin is more pronounced when used as an chemopreventive agent rather than as a chemotherapeutic agent against B(a)P induced lung carcinogenesis.
Abstract: Chemoprevention has emerged as a very effective preventive measure against carcinogenesis. Several bioactive compounds present in fruits and vegetables have revealed their cancer curative potential on benzo(a)pyrene (B(a)P) induced carcinogenesis. In the present study, the efficacy of quercetin on the level of lipid peroxides, activities of antioxidant enzymes and tumor marker enzymes in B(a)P induced experimental lung carcinogenesis in Swiss albino mice was assessed. In lung cancer bearing animals there was an increase in lung weight, lipid peroxidation and marker enzymes such as aryl hydrocarbon hydroxylase, gamma glutamyl transpeptidase, 5'-nucleotidase, lactate dehydrogenase and adenosine deaminase with subsequent decrease in body weight and antioxidant enzymes-superoxide dismutase, catalase, glutathione peroxidase, glutathione-S-transferase, glutathione reductase, reduced glutathione, vitamin E and vitamin C. Quercetin supplementation (25 mg/kg body weight) attenuated all these alterations, which indicates the anticancer effect that was further confirmed by histopathological analysis. Overall, the above data shows that the anticancer effect of quercetin is more pronounced when used as an chemopreventive agent rather than as a chemotherapeutic agent against B(a)P induced lung carcinogenesis.
TL;DR: In this article, detailed measurements of coastal topography, tsunami flow height, and deposit thickness made at Kalpakkam, India were made to assess the sedimentology and spatial distribution of the tsunami deposit.
TL;DR: The present results suggest that Chlorella vulgaris extract exerts its chemo-preventive effect by modulating the antioxidants status and lipid peroxidation during naphthalene intoxication.
Abstract: Alcoholic extract of the marine algae Chlorella vulgaris was examined for its free radical scavenging effect with reference to naphthalene-induced lipid peroxidation in serum, liver, and kidney of rats. Initially, upon naphthalene intoxication (435 mg/kg body weight, intraperitoneally), the lipid peroxidation activity increased significantly (P < 0.001), and in contrast, the enzymic antioxidants (superoxide dismutase, catalase, glutathione peroxidase) and non-enzymic antioxidants (glutathione, ascorbic acid, and α-tocopherol) levels decreased remarkably. When the naphthalene stressed rats were treated with Chlorella vulgaris extract (70 mg/kg body weight, orally), the lipid peroxidation activity reduced significantly (P < 0.001) and the activities of both the enzymic and non-enzymic antioxidants increased reaching near control values. The minimum concentration (70 mg/l) of the extract that exhibited maximum (85%) free radical scavenging activity was chosen for the experimental study. The present results suggest that Chlorella vulgaris extract exerts its chemo-preventive effect by modulating the antioxidants status and lipid peroxidation during naphthalene intoxication.
TL;DR: In this article, the effect of grain size, cation distribution, frequency and temperature on the dielectric properties of nanocrystalline cobalt ferrite particles has been studied.
Abstract: Nanocrystalline cobalt ferrite particles with the grain size of 8 nm were synthesized by using the co-precipitation technique and subsequently heat treated to obtain larger grain sizes. The effect of grain size, cation distribution, frequency and temperature on their dielectric properties has been studied. The dielectric constant (e') of 8 nm grains is found to be an order of magnitude higher and the dielectric loss (tanδ) is an order of magnitude smaller compared to those of the micron-size particles. The dielectric relaxation is found to be non-Debye in nature with the activation energy decreasing with thermal annealing due to structural perfection.
TL;DR: The result of this experiment shows that PCB significantly decreases the level of alpha-tocopherol, ascorbic acid and GSH and the activities of SOD, CAT, GPx, GR and GST with elevated levels of ROS and LPO.
TL;DR: In this article, an 8nm cobalt ferrite particles of 8nm grain size were synthesized by coprecipitation technique and subsequently suitably heat treated to obtain higher grain sizes and experimentally observed changes in dc electrical conductivity and Curie temperature with heat treatment have been attributed to the changes in the cation distributions as obtained from the Mossbauer and extended x-ray absorption fine structure (EXAFS) measurements and to the grain size.
Abstract: Nanocrystalline cobalt ferrite particles of 8nm grain size were synthesized by coprecipitation technique and subsequently suitably heat treated to obtain higher grain sizes The experimentally observed changes in the dc electrical conductivity and Curie temperature with heat treatment have been attributed to the changes in the cation distributions as obtained from the Mossbauer and extended x-ray absorption fine structure (EXAFS) measurements and to the grain size The activation energies for conduction as determined from the Arrhenius plots suggest that the conductivity is due to hopping of both electrons and holes The observed decrease in conductivity when the grain size is increased from 8to92nm is clearly due to the predominant effect of migration of some of the Fe3+ ions from octahedral to tetrahedral sites, as is evident from in-field Mossbauer and EXAFS measurements But the higher conductivity of the 102 and 123nm particles compared to that of the 92nm particles is attributed to the higher grain
TL;DR: A Scopulariopsis brevicaulis poultry farm isolate was chosen to study factors influencing keratinase production and the experimental values were found to be in accordance with the predicted values.
TL;DR: In this paper, the direct C-H arylation of 3,4-ethylenedioxythiophene (EDOT) under Heck-type experimental conditions is described.
TL;DR: The locally available (khadikraft) honey produced the best activity against Pseudomonas aeruginosa and was found to be better than all of the imported varieties of therapeutic honey.
Abstract: Objectives: Honey has had a valued place in traditional medicine for centuries. Renewed interest in honey for various therapeutic purposes, including treatment of infected wounds, has led to the search for different types of honey with antibacterial activity. In this study, we have assessed the antibacterial activity of different types of honey (manuka honey from Australia, heather honey from the United Kingdom, and locally marketed Indian honey). Methods: The agar dilution method was used to assess the antibacterial activity of honey against 152 isolates of Pseudomonas aeruginosa by determining minimum inhibitory concentrations. Results and conclusions: The locally available (khadikraft) honey produced the best activity against Pseudomonas aeruginosa and was found to be better than all of the imported varieties of therapeutic honey.
TL;DR: The results obtained reveal that the electrode under study could be used as an effective sensor for online monitoring of paracetomol and various parameters that influence the electrochemical behavior of the modified electrode were optimized by varying scan rates and pH.
TL;DR: The data demonstrated that Triphala formulation was associated with hypolipidemic effects on the experimentally induced hypercholesteremic rats.
Abstract: Hypercholesteremia is one of the risk factors for coronary artery disease. The present study highlights the efficacy of Ayurvedic herbal formulation Triphala (Terminalia chebula, Terminalia belerica, and Emblica officinalis) on total cholesterol, Low density lipoprotein (LDL), Very low density lipoprotein (VLDL), High density lipoprotein (HDL) and free fatty acid in experimentally induced hypercholesteremic rats. Four groups of rats were employed namely control, Triphala treated, hypercholesterolemia rats (4% Cholesterol + 1% cholic acid + egg yolk) and Triphala pre-treatment in hypercholesteremic rats. Results showed significant increase in the total cholesterol, LDL, VLDL, and free fatty acid in hypercholesteremic rats were significantly reduced in Triphala treated hypercholesteremic rats. The data demonstrated that Triphala formulation was associated with hypolipidemic effects on the experimentally induced hypercholesteremic rats.
TL;DR: This study indicates that O. sanctum has the potential for further evaluation as an ideal antioxidant for the noise induced oxidative stress and indicates that adaptation to noise does not occur in the brain regions even after 30 days of noise exposure.
Abstract: Noise is a pervasive aspect of many modern communities, work environments and its damaging effects, particularly the production of free radicals are not limited to the auditory organ. The oxidative stress in three discrete brain regions, in wistar strain male albino rats subjected to three different durations of noise exposures (acute, sub-acute and chronic noise stress) and the in vivo as well as the in vitro antioxidant activity of Ocimum sanctum has been analyzed. Broadband white noise (100dB) exposure significantly increased the levels of superoxide dismutase (EC 1.15.1.1), catalase (EC 1.11.1.6), glutathione peroxidase (EC 1.11.1.9), lipid peroxidation, oxidized glutathione (GSSG) and decreased the levels of reduced glutathione (GSH), GSH/GSSG ratio. However, administration of ethanolic extract of O. sanctum attenuates the alterations induced by noise exposure. The antioxidant activity of O. sanctum is also evident from its effectiveness in scavenging the free radicals in a dose dependent manner in the herbal antioxidant assays. The results indicate that adaptation to noise does not occur in the brain regions even after 30 days of noise exposure. The abundance of phytochemicals such as phenolics and flavanoids in O. sanctum may be held responsible for its attenuating activity. Therefore, this study indicates that O. sanctum has the potential for further evaluation as an ideal antioxidant for the noise induced oxidative stress.
TL;DR: It was observed that ethanolic leaf extract of C. fistula Linn protects the liver against DEN induced hepatic injury in rats and induction of oxidative stress in the liver was evidenced by increased LPO and fall in the activities of SOD and CAT.
TL;DR: Advocation of sulfated polysaccharides enhanced the antioxidant status, thereby preventing membrane injury and alleviating the microenvironment favourable for stone formation.
TL;DR: A more complete gene and protein structure of RDX is reported, including four additional exons and five new isoforms ofRDX that are expressed in human retina and inner ear and high‐resolution confocal microscopy in mouse inner ear demonstrates that radixin is expressed along the length of stereocilia of hair cells from both the organ of Corti and the vestibular system.
Abstract: Ezrin, radixin, and moesin are paralogous proteins that make up the ERM family and function as cross-linkers between integral membrane proteins and actin filaments of the cytoskeleton. In the mouse, a null allele of Rdx encoding radixin is associated with hearing loss as a result of the degeneration of inner ear hair cells as well as with hyperbilirubinemia due to hepatocyte dysfunction. Two mutant alleles of RDX [c.1732G>A (p.D578N) and c.1404_1405insG (p.A469fsX487)] segregating in two consanguineous Pakistani families are associated with neurosensory hearing loss. Both of these mutant alleles are predicted to affect the actin-binding motif of radixin. Sequence analysis of RDX in the DNA samples from the original DFNB24 family revealed a c.463C>T transition substitution that is predicted to truncate the protein in the FERM domain (F for 4.1, E for ezrin, R for radixin, and M for moesin) (p.Q155X). We also report a more complete gene and protein structure of RDX, including four additional exons and five new isoforms of RDX that are expressed in human retina and inner ear. Further, high-resolution confocal microscopy in mouse inner ear demonstrates that radixin is expressed along the length of stereocilia of hair cells from both the organ of Corti and the vestibular system. Hum Mutat 28(5), 417–423, 2007. Published 2007 Wiley-Liss, Inc.