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Selvakumar K.,University of Madras | Prabha R.L.,University of Madras | Saranya K.,University of Madras | Bavithra S.,University of Madras | And 2 more authors.
Human and Experimental Toxicology | Year: 2013

Polychlorinated biphenyls (PCBs) comprise a ubiquitous class of toxic substances associated with carcinogenic and tumor-promoting effects as well as neurotoxic properties. Reactive oxygen species, which is produced from PCBs, alters blood-brain barrier (BBB) integrity, which is paralleled by cytoskeletal rearrangements and redistribution and disappearance of tight junction proteins (TJPs) like claudin-5 and occludin. Quercetin, a potent antioxidant present in onion and other vegetables, appears to protect brain cells against oxidative stress, a tissue-damaging process associated with Alzheimer's and other neurodegenerative disorders. The aim of this study is to analyze the role of quercetin on oxidative stress markers and transcription of transmembrane and cytoplasmic accessory TJPs on cerebrum, cerebellum and hippocampus of female rats exposed to PCBs. Rats were divided into the following four groups. Group I: received only vehicle (corn oil) intraperitoneally (i.p.); group II: received Aroclor 1254 at a dose of 2 mg/kg body weight (bwt)/day (i.p); group III: received Aroclor 1254 (i.p.) and simultaneously quercetin 50 mg/kg bwt/day through gavage and group IV: received quercetin alone gavage. From the experiment, the levels of hydrogen peroxide, lipid peroxidation and thiobarbituric acid reactive substances were observed to increase significantly in cerebrum, cerebellum and hippocampus as 50%, 25% and 20%, respectively, after exposure to PCB, and the messenger RNA expression of TJP in rats exposed to PCBs is decreased and is retrieved to the normal level simultaneously in quercetin-treated rats. Hence, quercetin can be used as a preventive medicine to PCBs exposure and prevents neurodegenerative disorders. © 2013 The Author(s).


Bavithra S.,University of Madras | Selvakumar K.,University of Madras | Krishnamoorthy G.,Asan Memorial Dental College and Hospital | Venkataraman P.,SRM University | Arunakaran J.,University of Madras
Environmental Toxicology and Pharmacology | Year: 2013

Polychlorinated biphenyls (PCBs) are widespread persistent environmental contaminants that display a complex spectrum of toxicological properties, including neurotoxicity. Studies have shown that PCBs increase oxidative stress in brain, leading to apoptosis. The progressive loss of neurons in cerebral cortex and cerebellum, leads to various neurodegenerative diseases. Hence the present study is designed to determine PCBs toxicity toward neuronal cells and whether it could be inhibited by potent antioxidant melatonin. Four groups of adult male Wistar rats were treated for 30 days with corn oil, PCBs, PCBs. +. Mel and Melatonin, respectively. After treatment period the rats were euthanized and the brain was dissected to isolate cerebral cortex and cerebellum. The neuronal cells alone were then separated from the isolated brain regions, to detect the mRNA levels of apoptotic and neurofilament gene, a neuronal specific marker. Our results suggests that PCBs induces apoptosis in neuronal cells which is subsided by the anti apoptotic effect of melatonin. © 2013 Elsevier B.V.


Selvakumar K.,University of Madras | Bavithra S.,University of Madras | Suganthi M.,University of Madras | Benson C.S.,University of Madras | And 5 more authors.
Neurochemical Research | Year: 2012

Polychlorinated biphenyls (PCBs) exposure produces neurodegeneration and induces oxidative stress. Neuroprotective role of quercetin, on PCBs induced apoptosis in hippocampus has not yet been studied. The present study is focused to see whether quercetin supplementation precludes against PCBs induced oxidative stress and hippocampal apoptosis. The results have shown that quercetin at 50 mg/kg bwt/30 days has protected oxidative stress in hippocampus of adult male rats. Quercetin, a free radical scavenger decreased the levels of oxidative stress markers in the hippocampus of simultaneous PCB+quercetin treated rats. The pro-apoptotic and anti-apoptotic molecules such as Bad, Bid, Bax and Bcl2 were altered in the hippocampus of experimental animals. PCBs increased the DNA damage and induced neurodegeneration were assessed by histological studies. PCB induced ROS may be linked to increased hippocampal neuronal apoptosis. Quercetin supplementation decreased the neuronal damage and scavenged the free radicals induced by PCBs and protects PCBs induced apoptosis and oxidative stress. © Springer Science+Business Media, LLC 2011.


Selvakumar K.,University of Madras | Bavithra S.,University of Madras | Krishnamoorthy G.,Asan Memorial Dental College and Hospital | Venkataraman P.,SRM University | Arunakaran J.,University of Madras
TheScientificWorldJournal | Year: 2012

Present study is aimed to evaluate the ameliorative role of quercetin on PCBs-induced oxidative stress in hippocampus of Wistar rats. Group I rats received vehicle (corn oil) intraperitoneally (i.p); Group II received quercetin 50mg/kgbwt/day (gavage); Group III received PCB 2mg/kgbwt/day (i.p); Group IV received PCB (i.p) and simultaneously quercetin through gavage. After 30days, rats were euthanized and hippocampus was dissected from each rat brain. Oxidative stress was assessed by determining the levels of H2O2, LPO, Pcc, and alteration in the functional markers such as CK, AchE, and ATPases activities in the hippocampus of control and experimental animals. A significant increase in the levels of stress markers and decrease in level of functional markers were observed in PCBs-treated rats. Moreover DNA fragmentation and histological studies were ascertained to confirm PCBs toxicity. In conclusion, quercetin shows a protective role against PCBs-induced oxidative damage in rat hippocampus. Copyright 2012 Kandaswamy Selvakumar et al.


Krishnamoorthy G.,Asan Memorial Dental College and Hospital | Selvakumar K.,University of Madras | Venkataraman P.,SRM University | Elumalai P.,University of Madras | Arunakaran J.,University of Madras
Interdisciplinary Toxicology | Year: 2013

Sertoli cell proliferation is attenuated before attaining puberty and the number is fixed in adult testes. Sertoli cells determine both testis size and daily sperm production by providing physical and metabolic support to spermatogenic cells. Polychlorinated biphenyls (PCBs) exposure disrupts functions of Sertoli cells causing infertility with decreased sperm count. On the other hand, lycopene is improving sperm count and motility by reducing oxidative stress in humans and animals. Hence we hypothesized that PCBs-induced infertility might be due to Sertoli cell apoptosis mediated by oxidative stress and lycopene might prevent PCBs-induced apoptosis by acting against oxidative stress. To test this hypothesis, animals were treated with vehicle control, lycopene, PCBs and PCBs + lycopene for 30 days. After the experimental period, the testes and cauda epididymidis were removed for isolation of Sertoli cells and sperm, respectively. We observed increased levels of oxidative stress markers (H2O2 and LPO) levels, increased expression of apoptotic molecules (caspase-8, Bad, Bid, Bax, cytochrome C and caspase-3), decreased anti-apoptotic (Bcl2) molecule and elevated apoptotic marker activity (caspase-3) in Sertoli cells of PCBs-exposed animals. These results were associated with decreased sperm count and motility in PCBs exposed animals. On the other hand, lycopene prevented the elevation of Sertoli cellular apoptotic parameters and prevented the reduction of sperm parameters (count and motility). The data confirmed that lycopene as an antioxidant scavenged reactive oxygen substances, prevented apoptosis, maintained normal function in Sertoli cells and helped to provide physical and metabolic support for sperm production, thereby treating infertility in men. Copyright © 2013 SETOX & IEPT, SASc.


PubMed | Asan Memorial Dental College and Hospital and Madha Dental College and Hospital
Type: Case Reports | Journal: Indian journal of dental research : official publication of Indian Society for Dental Research | Year: 2016

Lip pits are a rare congenital anomaly that presents on the upper or lower lip or the commissure of the lips. Lip pits are an autosomal dominant trait occurring almost always in association with cleft lip or palate. They most commonly occur in association with developmental disturbances such as Van der Woudes syndrome, popliteal pterygium syndrome, oro-facial-digital syndrome, Marres-Cremers syndrome, and Hirschsprung disease. Its occurrence in nonsyndromic individuals is extremely rare with only a handful of cases reported. The identification of lip pits with other associated anomalies is crucial for genetic counseling; we report a case of nonsyndromic presentation of bilateral lip pits.


Tilak A.H.,Asan Memorial Dental College and Hospital | Geetha Priya S.,Asan Memorial Dental College and Hospital | Raja K.,Asan Memorial Dental College and Hospital
International Journal of Pharma and Bio Sciences | Year: 2012

Dental unit waterlines (DUWL) are an integral part of dental surgery equipment, supplying water as a coolant, primarily for air turbine and ultrasonic scalers. Dental unit water lines (DUWL) used to irrigate the oral cavity during routine dental practice is highly contaminated. Concern about indoor air quality is increasing, and more attention is being laid on the aerosol and splatterproduced during dental procedures 1. The source of bacterial contamination within the dental unit water supply is thought to be caused by micro-colonies of proliferating bacteria, fungi and protozoa on the inner surface of the water lines, forming a biofilm2. The unique feature of dental chair water lines is the capacity for rapid development of a biofilm on the dental water supply lines combined with the generation of potentially contaminated aerosols. The present review emphasizes theunderlying biological cause of waterline colonisation by microorganisms, the evidence of potentialhealth consequences and possible means of improving the quality of dental water.


PubMed | Ram Dental Care, Asan Memorial Dental College and Hospital, Future Dental Center, Chettinad Dental College and Research Institute and Ibn Sina National College for Medical Studies
Type: Journal Article | Journal: Journal of International Society of Preventive & Community Dentistry | Year: 2016

Dimension of dental implant is an important parameter which has a considerable impact on the biomechanical load transfer characters and its prognosis. Excessive stress in the bone-implant interface may result in the failure of the implant. The aim of this study was to evaluate the impact of implant diameter and length on neighboring tissues around the implant. The results of the study will help in developing a scientific methodology to select appropriate implant diameter and length.In this study, tapered implants of different diameter and length were numerically analyzed using bone-implant models developed from computed tomography generated images of mandible with osseointegrated implants. The impact of various diameters on stress distribution was examined using implants with a length of 13 mm and diameters of 3.5 mm, 4.3 mm and 5.0 mm. Implants with a diameter of 4.3 mm and lengths of 10 mm, 13 mm, 16 mm was developed to examine the impact of various implant length. All materials were assumed to be linearly elastic and isotropic. Masticatory load was applied in a natural direction, oblique to the occlusal plane. The Statistical Package for the Social Sciences software package was used for statistical analysis.Maximum von Mises stresses were located around the implant neck. It was demonstrated that there was statistically significant decrease in von Mises stress as the implant diameter increased.Within the limitations of this study there was statistically significant decrease in von Mises stress as the implant diameter increased.


PubMed | Asan Memorial Dental College and Hospital and Karpaga Vinayaga Institute of Dental science
Type: Journal Article | Journal: Journal of pharmacy & bioallied sciences | Year: 2016

Pediatricians and other health-care providers could play an invaluable role in ensuring the maintenance of optimal preventive as well as curative dental health in children. This study was aimed at assessing the pediatricians perspective on basic oral health care in children in Kanchipuram district.A questionnaire survey was carried out among Pediatricians which covered various aspects of knowledge, attitude, and role of pediatricians in preventive dental care. The collected data were tabulated, and percent frequency distributions for responses to every question were assessed.None of the participants reported that pediatricians are responsible for infant oral health presumes that pediatricians are not examining the oral cavity as a part of routine. All of the pediatricians gave nutritional counseling to the parents but only 7% of them of caries. All the pediatricians liked the concept of an association between lack of knowledge among pediatricians and pediatric dentist and establishment of a dental home along with a medical home.From the present study, we conclude that there is a lack of awareness about prevention of dental caries among pediatricians in Kanchipuram district. To overcome this, advocating dentists as part of well-child care and establishing dental home along with medical home. Publishing pediatric journals concerning about the oral health to improve the knowledge is also essential in promoting good oral health hygiene.


PubMed | Asan Memorial Dental College and Hospital and Karpaga Vinayaga Institute of Dental science
Type: Journal Article | Journal: Journal of pharmacy & bioallied sciences | Year: 2016

Dental trauma is one of the most common and significant problems met in all dental offices almost every day. In particular, injury to the anterior teeth is more vulnerable as it may affect the psychosocial behavior, severe emotional complications can occur leading to disturbances in their mental attitude. Cosmetic (lingual) orthodontics is the recent development in the field of dentistry in the last few decades. Patients are more concerned about their appearance during the treatment and are affected by psychosocial issues because of labially placed brackets, thus leading to the evolution of lingual orthodontic appliances. In this article, we are sharing our clinical experience treating a complicated crown-root fracture using the lingual orthodontic technique.

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