Biomedical subjects

T D Dogra

Publications and source records attributed to T D Dogra.

At least 19 recordsLinked to original sources

PubMed2006

Arsenic-induced cell death in liver and brain of experimental rats.

Arsenic is a well established human carcinogen and is ubiquitous in the environment. The present study demonstrates the effect of acute arsenic administration at three different doses in liver and brain of Wistar rats. Sodium arsenite was administered orally at doses of 6.3 mg/kg, 10.5 mg/kg and 12.6 mg/kg of body weight on the basis of a lethal dose 50% (LD50) for 24 hr. After administration of arsenites, liver and brain were analyzed for various parameters of oxidative stress, histopathological changes and caspase-3 activity. Glutathione levels were decreased significantly in the liver at all doses. In liver the following biochemical changes were observed, a significant lipid peroxidation and cytochrome-P450 induction along with significant decrease in catalase and superoxide dismutase was observed at 10.5 mg/kg and 12.6 mg/kg. The activity of glutathione peroxidase was increased significantly at all doses. In brain, no significant change was observed at 6.3 mg/kg. However, a significant increase in lipid peroxidation and glutathione peroxidase activity along with significant decrease in the activity of glutathione, catalase and superoxide dismutase was observed at 10.5 mg/kg and 12.6 mg/kg. The activity of glutathione-S-transferase was decreased significantly in both liver and brain at 10.5 and 12.6 mg/kg. No significant alteration in the activity of glucose-6-phosphate dehydrogenase and glutathione reductase was observed in either liver or brain at any dose. Dose-dependent histopathological changes, observed in both liver and brain are also described. A significant increase in caspase-3 activity was observed at all doses in liver and at 10.5 and 12.6 mg/kg in brain. Sodium arsenite caused DNA cleavage into fragments and manifested as "DNA laddering", a hallmark of apoptosis.

Animals↗

PubMed2006

The Abbreviated Injury Scale and its correlation with preventable traumatic accidental deaths: a study from South Delhi.

Anatomic trauma scoring systems are fundamental to trauma research. The Abbreviated Injury Scale (AIS) and its derivative, the Injury Severity Score (ISS), are the most frequently used scales. In a prospective study, 400 autopsies of road traffic accident victims performed between January 2002 and December 2003 were coded according to the AIS and ISS methods. All the cases were classified into different injury groups according to the Injury Severity Scale. Fifty-eight cases (14.5%) were assigned an ISS value of <25; 244 (61%) cases were valued between 25-49; 38 cases (9.5%) were valued between 50-74 and 60 (15%) cases had a value of 75. On analysis of medical care, in cases with ISS<50, about 96% of the victims did not receive optimal care quickly enough with a lack of pre-hospital resuscitation measures and lengthy transportation time to hospital being of major importance.

Abbreviated Injury Scale↗

PubMed2005

Arsenic induced apoptosis in rat liver following repeated 60 days exposure.

BACKGROUND: Accumulation of the wide spread environmental toxin arsenic in liver results in hepatotoxcity. Exposure to arsenite and other arsenicals has been previously shown to induce apoptosis in certain tumor cell lines at low (1-3 microM) concentration. AIM: The present study was focused to elucidate the role of free radicals in arsenic toxicity and to investigate the nature of in vivo sodium arsenite induced cell death in liver. METHODS: Male wistar rats were exposed to arsenite at three different doses of 0.05, 2.5 and 5mg/l for 60 days. Oxidative stress in liver was measured by estimating pro-oxidant and antioxidant activity in liver. Histopathological examination of liver was carried out by light and transmission electron microscopy. Analysis of DNA fragmentation by gel electrophoresis was used to identify apoptosis after the exposure. Terminal deoxy-nucleotidyl transferase mediated dUTP Nick end-labeling (TUNEL) assay was used to qualify and quantify apoptosis. RESULTS: A significant increase in cytochrome-P450 and lipid peroxidation accompanied with a significant alteration in the activity of many of the antioxidants was observed, all suggestive of arsenic induced oxidative stress. Histopathological examination under light and transmission electron microscope suggested a combination of ongoing necrosis and apoptosis. DNA-TUNEL showed an increase in apoptotic cells in liver. Agarose gel electrophoresis of DNA of hepatocytes resulted in a characteristic ladder pattern. CONCLUSION: Chronic arsenic administration induces a specific pattern of apoptosis called post-mitotic apoptosis.

Administration, Oral↗

PubMed2005

Dimethoate-induced effects on antioxidant status of liver and brain of rats following subchronic exposure.

Dimethoate, an organophosphate pesticide, is used in controlling the pests of a variety of crops. The study was carried out to understand the role of dimethoate in inducing oxidative stress leading to generation of free radicals and alterations in antioxidant enzymes and scavengers of oxygen free radicals. The effects of subchronic exposure of dimethoate in the production of oxidative stress were evaluated in male Wistar rats in the present study. Dimethoate was administered orally at doses 0.6, 6, and 30 mg/kg for 30 days in these rats. The results indicated an increase in levels of hepatic Cytochrome P450, lipid peroxidation, catalase, superoxide dismutase, glutathione peroxidase and glutathione reductase in liver and brain at doses 6 and 30 mg/kg. There were no significant changes in the level of glucose-6-phosphate dehydrogenase activity except in liver at 30 mg/kg. A decrease in glutathione was observed at 30 and 6 mg/kg in both liver and brain. Glutathione-S-transferase increased at 30 and 6 mg/kg in liver and 30 mg/kg in brain. Erythrocyte acetylcholinesterase was inhibited at 30 and 6 mg/kg doses. Dose-dependent histopathological changes were seen in both liver and brain. This study concludes that oxidative stress due to dimethoate may be ascribed to induction of Cytochrome P450, inhibition of AChE and disturbance in activities of GSH and GST enzymes causing lipid peroxidation and histological and electron microscopic changes in liver and brain.

Administration, Oral↗

PubMed2005

Effects of acute dimethoate administration on antioxidant status of liver and brain of experimental rats.

Organophosphorus compounds may induce oxidative stress leading to generation of free radicals and alterations in antioxidant and scavengers of oxygen free radicals. The present study demonstrates effect of acute exposure of dimethoate in causation of oxidative stress in male Wistar rats. Dimethoate was administered orally at doses 45, 75 and 90 mg/kg of body weight on the basis of LD(50) for 24 h. After administration of doses, the liver and brain homogenates were analyzed for various parameters of oxidative stress. The results indicated an increase in hepatic cytochrome P450, lipid peroxidation, catalase, superoxide dismutase, glutathione peroxidase, glutathione reductase in liver and brain at 90 and 75 mg/kg doses. There were no significant changes in the levels of glucose-6-phosphate dehydrogenase activity in both liver and brain. Similarly, there were no significant changes in hepatic glutathione and glutathione-S-transferase activities. However, there was a significant increase in glutathione and glutathione-S-transferase in brain at 90 mg/kg dose only. Erythrocyte acetylcholinesterase was inhibited at all doses used. Dose-dependent histopathological changes, observed in both liver and brain, are also described.

Administration, Oral↗

PubMed2005

Fatal occupational injuries in the South Delhi construction industry: a retrospective study.

One hundred and forty-five unselected autopsy cases of construction site accidents received from South Delhi were studied during the period from 1996--2002. Data for the study was gathered from autopsy reports and hospital records. The cases represented approximately 1.61% of all autopsy cases received from South Delhi at the All India Institute of Medical Sciences, New Delhi (India). Data was analysed with regard to the age and sex of the victim, the part of the body involved, the manner of accident, the cause of death and the pattern of injuries in different body regions. Death occurred at the scene of the fatal event in thirty-four cases; forty-three cases were dead on arrival at the hospital; sixty-eight cases died after being admitted to the hospital. Ethanol was detected in the blood of 16% of the cases.

Accidents, Occupational↗

PubMed2004

An unusual suicide with a safety razor blade--a case report.

A 29-year-old male was found dead lying in a pool of blood inside a community toilet locked from inside. The individual is alleged to have committed suicide by cutting his throat with a safety razor blade, which was found at the scene by the investigating police authority. The deceased, as per his relatives, was suffering from depression for the last few days.

Adult↗

PubMed2004

Suicide among children and adolescents in South Delhi (1991-2000).

OBJECTIVE: Suicide among youth is of great concern and a subject requires thorough study to formulate prevention strategy. In this paper the incidence and trends of suicide among children and adolescent of South Delhi have been reported. METHODS: A retrospective analysis was carried out on 222 cases of suicidal deaths pertaining to age group of 10-18 years, the postmortem examination on the body of which were conducted in Department of Forensic Medicine and Toxicology, All India Institute of Medical Sciences, New Delhi during the period from 1st January 1991 to 31st December 2000. The particular of cases were analyzed according to age group, sex, method used and causes of committing suicide. RESULTS: Out of 222 cases 123(55.4%) were of girls (Female: Male 1.24:1). Commonest age group involved was 15-18 years in both the sexes. Commonest method used for committing suicide was hanging (57% in girls, 49.5% in boys) followed by poisoning (37.4% in girls, 49.5% in boys). CONCLUSION: Methods used to commit suicide are widely available and are difficult to restrict. Therefore, suicide prevention strategy based on risk factors could be more effective rather than limiting the access to methods.

Adolescent↗

PubMed2004

Suicide notes in India: what do they tell us?

Over 100,000 people commit suicide each year in India; yet, there has been limited micro-based study. This study marks the first study of suicide notes in India. The sample consisted of all available note-writers (n = 50), with a comparative sample of non-note writers (n = 50) of all suicides (n = 320, 16.47% of all postmortems) during a 1(1/2) year period in the New Delhi area, India. Using the demographic (descriptive) schema of Ho, Yip, Chiu, and Halliday (1998), the results show that note writers do not differ greatly from other suicides. Males wrote more notes, but the more intriguing finding is the fact that suicide in India is associated to an array of psychiatric/psychological and social factors.

Journal Article↗

PubMed2004

Rail traffic accidents: a retrospective study.

One hundred and twenty-seven autopsy cases of rail traffic accidents received from South Delhi were studied during the period from 1996-2002. Data for the study was gathered from autopsy reports and hospital records. The cases represented approximately 1.41% of all autopsy cases received from South Delhi at the All India Institute of Medical Sciences, New Delhi (India). Data was analysed with regard to the age and sex of the victim, the part of the body involved and the pattern of injuries in different body regions. Death occurred at the scene of the fatal event in twenty-eight cases; another twenty-eight cases were brought in dead to the hospital. Seventy-one cases died after being admitted to the hospital. Ethanol was detected in the blood of 17.4% of cases.

Accidents↗

PubMed2004

Suicide by a transvestite or sexual asphyxia? A case report.

Autoerotic asphyxial activity may at times result in unexpected death. Although the majority of deaths that occur during autoerotic asphyxial episodes are accidental, the possibility of suicide must always be entertained. In the case presented here, a 22-year-old married male was found hanging by his neck in his bedroom, which was locked from the inside. He was suspended by a 'lungi' (male wrap-around cloth) from the ceiling fan hook in his room, with his feet touching the ground. He was dressed in a brassiere, panties, and silver anklets. There was no evidence of previous perverse behaviour, and investigation disclosed no evidence of previous autoerotic sexual activity, homosexual behaviour, drug abuse or suicidal ideation.

Asphyxia↗

PubMed2004

A fatal impaling injury in a road traffic accident: a case report.

A 17-year old, thin-built male was sitting in a bus on the right side of the rear seat. The same side of the bus accidentally hit some iron rods, meant for construction work, projecting from the tail end of a small truck. The incident happened when the bus driver tried to manoeuvre the bus towards the left side of the truck, standing at a red traffic light intersection. One of the iron-rods entered the bus through the glass window next to which the victim had been sitting and penetrated his chest cavity from the side, lacerating both the lungs and exiting through the left shoulder blade. The individual died on his way to hospital.

Accidents, Traffic↗

PubMed2003

An unusual fatal injury due to tyre burst: a case report.

A 20 year-old male driver of a heavy duty crane, employed in an industry located in an industrial area on the outskirts of Delhi was fatally injured while repositioning an ill-fitted locking rim of a crane tyre (Fig. 1). The inner tube of the crane tyre had accidentally burst, dislodging the loose iron-locking rim, which hit the individual with a great force resulting in multiple injuries. He died on his way to the hospital.

Accidents, Occupational↗

PubMed2003

Decapitation in road traffic accident--a case report.

A 20-year-old girl along with four of her friends, all in their early 20s, met with a fatal accident in the early hours of the day. Their car was hit by a speeding truck at a crossing. All the occupants of the car sustained multiple injuries and died on the spot. The girl was decapitated in the accident. Her head was recovered outside the mangled remains of the vehicle and the rest of the body was extracted from the co-driver's seat of the damaged vehicle.

Accidents, Traffic↗

PubMed2003

An unusual suicide by stabbing: a case report.

A 50-year old cobbler, employed in a paramilitary unit, was found dead in a pool of blood in his shop inside the unit line in the morning. He had multiple stab wounds on his chest and was alleged to have committed suicide by repeated self-stabbing on the chest with a sharp iron chisel, which was found clenched in his right hand by the investigating officer. Fifteen wounds were communicating with the chest cavity, injuring the vital anatomical structures. The individual, according to the unit personnel, was not suffering from any physical or mental disorder and was not on any medication.

Forensic Medicine↗

PubMed2003

Electrocution in South Delhi: a retrospective study.

One hundred and fifty three unselected autopsy cases of electrocution received from South Delhi were studied during the period 1996-2001. Data for the study was gathered from autopsy reports and hospital records. The cases represented approximately 1.98% of all autopsy cases received from South Delhi at the All India Institute of Medical Sciences, New Delhi (India). Data was analysed with regard to the age and sex of the victim, season of the year, site of the body, time of day, place of occurrence and presence of entry and exit wounds on the body. Death occurred at the scene of the fatal event in 150 cases and three cases died in hospital. Three cases showed no electric burn marks on the body; the cause of death in one of these cases was polytrauma due to a fall from a height and one case had committed suicide.

Adolescent↗

PubMed2003

Validation of qualitative test for phosphine gas in human tissues.

Phosphine has been known to science since the birth of modern chemistry. WHO reports that the technical product usually has a foul odour, like "fishy" or "garlicky" because of the presence of substituted phosphines and diphosphine (P2H4). Many medico-legal autopsy cases have been reported positive for aluminium phosphide even though there was neither any suspicion of consuming aluminium phosphide nor any clinical findings, postmortem findings or circumstantial evidences. The present study was carried out to validate the qualitative test, presently applied in many laboratories for testing phosphine. It was observed that 65% of human tissues in saturated solution of common salt show positivity for phosphine gas on the first day of autopsy.

Forensic Medicine↗

PubMed2002

Application of DNA fingerprinting in medicolegal practice.

Fingerprinting is thought to establish the identify of an individual in forensic cases. The technique is extensively used for forensic purposes. Deoxyribonucleic acid (DNA) is the vehicle of generational transference of heritable unit. While arching markers for genetic disease professor Alec Jeffreys discovered that certain regions of DNA showed variations in the number of tandem repeats known as variable number of tandem repeats (VNTRs). Thus DNA fingerprint was named by observing the number of repeated sequences which differ from individual to individual. The structure of DNA is quite flexible, within the nucleus of each cell resides an identical copy of the individual's genetic material, DNA. The coding regions of the genomic DNA are known as genes. The DNA fingerprinting in forensic science has generated considerable excitement in the criminal justice community. DNA fingerprinting can be applied to identify an individual in criminal and civil cases. Polymerase chain reaction has revolutionised molecular biology it has an ability to amplify (usually fewer than 3000 bp) a particular sequence of DNA into million of copies in a very short period. Consequently only a very tiny amount of an organism's DNA needs to be available originally. This property of polymerase chain reaction has enabled to analyse many forensic samples particularly which are degraded. Microsatellite DNA or commonly as short tandem repeats are scattered throughout the human genome and occur on an average of every 10,000 nucleotides. Microsatellite markers are considered to be the most powerful genetic markers. Collection, preservation and handling are the integral part of DNA fingerprinting analysis. There are various methods to isolate DNA from different biological materials but presently most of the laboratories prefer using FTA paper. The age of humans can be estimated by using DNA based on telomere shortening.

Clinical Medicine↗