D.N. Bhardwaj

Study on arsenic level in public water supply of Delhi using hydride generator accessory coupled with atomic absorption spectrophotometer.

Surveillance of drinking water is essentially a health measure intended to protect the public from water borne diseases. Hydride generator accessory coupled with atomic absorption spectrophotometer was used to analyze arsenic level in 49 ground water samples collected from different areas of Delhi. Arsenic level in ground water samples was in the range of 0.0170 to 0.100 ppm (Mean-0.0431, Standard Deviation-0.0136, Std. error of Mean-0.00194) with minimum concentration at Raney Well No. 7 (0.0170 ppm) and maximum at Kotla Mubarak Pur (0.100 ppm). Arsenic containing sediments and percolation of chemicals into soil as the result of dumping of garbage rich in chemicals into open landfills could be the possible source of arsenic in ground water of Delhi. Extensive survey and continuous monitoring is required to be made to assess the magnitude of problem and earlier intervention.

The aging human cochlear nucleus: Changes in the glial fibrillary acidic protein, intracellular calcium regulatory proteins, GABA neurotransmitter and cholinergic receptor.

The human auditory system is highly susceptible to environmental and metabolic insults which further affect the biochemical and physiological milieu of the cells that may contribute to progressive, hearing loss with aging. The cochlear nucleus (CN) is populated by morphologically diverse types of neurons with discrete physiological and neurochemical properties. Between the dorsal and the ventral cochlear nucleus (DCN and VCN), the VCN is further sub-divided into the rostral (rVCN) and caudal (cVCN) sub-divisions. Although, information is available on the age related neurochemical changes in the mammalian CN similar reports on human CN is still sparse. The morphometry and semiquantitative analysis of intensity of expression of glial fibrillary acidic protein (GFAP), calcium binding proteins (calbindin, calretinin and parvalbumin), gamma amino butyric acid (GABA) and nicotinic acetyl choline receptor (nAchR) beta 2 immunostaining were carried out in all three sub-divisions of the human CN from birth to 90 years. There was increased GFAP immunoreactivity in decades 2 and 3 in comparison to decade 1 in the CN. But no change was observed in rVCN from decade 4 onwards, whereas intense staining was also observed in decades 5 and 6 in cVCN and DCN. All three calcium binding proteins were highly expressed in early to middle ages, whereas a significant reduction was found in later decades in the VCN. GABA and nAchR beta 2 expressions were unchanged throughout in all the decades. The middle age may represent a critical period of onset and progression of aging changes in the CN and these alterations may add to the deterioration of hearing responses in the old age.

Practical guidelines for setting up neurosurgery skills training cadaver laboratory in India

Though the necessity of cadaver dissection is felt by the medical fraternity, and described as early as 600 BC, in India, there are no practical guidelines available in the world literature for setting up a basic cadaver dissection laboratory for neurosurgery skills training. Hands-on dissection practice on microscopic and endoscopic procedures is essential in technologically demanding modern neurosurgery training where ethical issues, cost constraints, medico-legal pitfalls, and resident duty time restrictions have resulted in lesser opportunities to learn. Collaboration of anatomy, forensic medicine, and neurosurgery is essential for development of a workflow of cadaver procurement, preservation, storage, dissection, and disposal along with setting up the guidelines for ethical and legal concerns.

Suicide pact by drowning with bound wrists: A case of medico-legal importance:

Suicide pacts are uncommon and mainly committed by male–female pairs in a consortial relationship. The victims frequently choose methods such as hanging, poisoning, using a firearm, etc; however, a case of a suicide pact by drowning is rare in forensic literature. We report a case where a male and a female, both young adults, in a relationship of adopted “brother of convenience” were found drowned in a river. The victims were bound together at their wrists which helped with our conclusion this was a suicide pact. The medico-legal importance of wrist binding in drowning cases is also discussed in this article.

A Case of Accidental Fatal Aluminum Phosphide Poisoning Involving Humans and Dogs

Aluminum phosphide is one of the commonest poisons encountered in agricultural areas, and manner of death in the victims is often suicidal and rarely homicidal or accidental. This paper presents an unusual case, where two humans (owner and housemaid) and eight dogs were found dead in the morning hours inside a room of a house, used as shelter for stray dogs. There was allegation by the son of the owner that his father had been killed. Crime scene visit by forensic pathologists helped to collect vital evidence. Autopsies of both the human victims and the dogs were conducted. Toxicological analysis of viscera, vomitus, leftover food, and chemical container at the crime scene tested positive for aluminum phosphide. The cause of death in both humans and dogs was aluminum phosphide poisoning. Investigation by police and the forensic approach to the case helped in ascertaining the manner of death, which was accidental.

The human trochlear and abducens nerves at different ages - a morphometric study.

The trochlear and abducens nerves (TN and AN) control the movement of the superior oblique and lateral rectus muscles of the eyeball, respectively. Despite their immense clinical and radiological importance no morphometric data was available from a wide spectrum of age groups for comparison with either pathological or other conditions involving these nerves. In the present study, morphometry of the TN and AN was performed on twenty post-mortem samples ranging from 12-90 years of age. The nerve samples were processed for resin embedding and toluidine blue stained thin (1µm) sections were used for estimating the total number of myelinated axons by fractionator and the cross sectional area of the nerve and the axons by point counting methods. We observed that the TN was covered by a well-defined epineurium and had ill-defined fascicles, whereas the AN had multiple fascicles with scanty epineurium. Both nerves contained myelinated and unmyelinated fibers of various sizes intermingled with each other. Out of the four age groups (12-20y, 21-40y, 41-60y and >61y) the younger groups revealed isolated bundles of small thinly myelinated axons. The total number of myelinated fibers in the TN and AN at various ages ranged from 1100-3000 and 1600-7000, respectively. There was no significant change in the cross-sectional area of the nerves or the axonal area of the myelinated nerves across the age groups. However, myelin thickness increased significantly in the AN with aging (one way ANOVA). The present study provides baseline morphometric data on the human TN and AN at various ages.

Comparison of unbiased stereological estimation of total number of cresyl violet stained neurons and parvalbumin positive neurons in the adult human spiral ganglion

Estimation of total number of neurons in the spiral ganglion (SG) at various ages and their functional status is important as these neurons are constantly exposed to noise and other environmental factors that may lead to neuronal loss with aging due to excitotoxic damage. Parvalbumin (PV) is a calcium-binding protein (CBP), found in highly metabolically active neurons. It helps in buffering cytosolic calcium, which is essential for neurotransmitter release. The neurons in the adult human SG express PV more strongly than other CBPs like calbindin and calretinin. These CBPs can be used as signatures to recognise neurons. In the present study, we quantified the number of neurons expressing PV by unbiased stereology and compared it to the number of neurons stained by cresyl violet (CV), which is a Nissl stain, in the adult human SG. Five adult human cadaveric temporal bones were obtained from the forensic science mortuary, after due clearance from the institute ethics committee. Independent CV stained and PV immunostained sections were used to estimate the total number of neurons (optical fractionator), with StereoInvestigator (SI) software. The estimated total number of SG neurons was 27,485±3251 and 26,705±1823 in the PV and CV stained sections, respectively. There was no significant difference between the estimates (p=0.552). Therefore, CV staining is simpler and more cost effective when estimating neuronal number. Although PV stains spiral ganglion neurons (SGNs) with a greater intensity and provides a functional status, its tedious protocol limits its use for quantification.

Ice pick death: A case report and discussion of the injury pattern

Death due to ice pick injury rarely reported in forensic literature. We report death of a 16-year old male, who was allegedly assaulted on chest, back and thigh by his school-mate, with an ice pick. The accused had got the ice pick from his fathers ice shop to attack the victim. The multiple stabs to the chest region had perforated the lung and penetrated the heart chambers. The victim succumbed to death on the way to hospital and medico-legal autopsy was conducted. The injuries inflicted by the ice pick are highlighted and its pattern is discussed in this article, owing to the peculiar nature of the wounds produced by the ice-pick.

Changing Population of Neurons and Glia in the Human Cochlear Nucleus During Aging

The human cochlear nucleus (CN) is composed of dorsal and the ventral subdivisions. Neurons of this nucleus are unique because they respond to specific impulses arising from the cochlea. This nucleus and the neurons of the cochlea are continuously exposed to external stimuli and can degenerate with aging. This may be one of the causes of presbycusis—an age related hearing loss. One of the therapeutic interventions for this condition is a brainstem implant. An understanding of the morphology of the CN with aging changes will help making better implants for these patients. In the present study we have investigated the qualitative and quantitative changes in the neuronal and glial population of various sub-divisions of human CN at different ages. Forty one (1st to 9th decade) CN were processed for morphometry and stereology. Although the volume of the nucleus does not change with aging, neuronal number showed significant changes with aging. The data from the current morphometric report may facilitate in understanding the physiology of prebycusis, provide insight for cochlear nuclear implantation and eventually help clinicians to rehabilitate geriatric patients with hearing loss.

Skin suicide note written in mehndi (henna)

Suicide messages on the skin are rare. Until now, in all reported cases, the writing tool used by the victims has been a pen. We report a suicide case by hanging in which the victim had written a note on her palm in mehndi, or henna, at a wedding ceremony three days before the fatal act. The note was discovered at autopsy.