Role of forensic odontology in the world's major mass disasters: facts and figures

Forensic identification of the victims in mass disasters is essential, not only for humanitarian reasons, but also for civil or criminal investigative need. The number of victims identified with the help of forensic odontology in various mass disasters in the world has been analysed and discussed. The result depicts the necessity of keeping proper dental records at institutional and individual level. Thus the use of forensic odontology in a series of mass disasters has been explored. The most common aspect of forensic odontology that a general practitioner is likely to encounter is the supply of ante-mortem records to aid in human identification.

CLINICAL RELEVANCE

The need for proper dental record-keeping by general dental practitioners is highlighted by discussing the role of forensic odontology in some of the world's major mass disasters.

Full length genomes of genotype IIIA Hepatitis A Virus strains (1995-2008) from India and estimates of the evolutionary rates and ages

With the changing epidemiology, outbreaks of Hepatitis A Virus (HAV) have been reported from different parts of India. To characterize HAV strains circulating in India (1995-2008), 6 full genome sequences of the predominant genotype, IIIA, were determined. Further, applying the Bayesian Markov Chain Monte Carlo (MCMC) framework to the full genomes of Indian HAV strains as well as other global strains (human as well as simian), we derived the mean nucleotide substitution rate and evolutionary timescales with emphasis on the age of genotype III and IIIA strains. The genomic length of all the 6 HAV isolates was 7464 nt excluding the poly A tract. Phylogenetic analysis confirmed that all the Indian isolates were close to Nor-21 (AJ299464) and HMH (AY644337) of subgenotype IIIA. The ORF of the isolates when compared within genotype III at amino acid level showed a highly conserved pattern. Under the best fit expansion population relaxed molecular clock model, the estimated mean substitution rate of the HAV full genomes (human and simian strains) was 1.73 x 10(-4) substitutions/site/year based on which the earliest transmission of HAV from simian to humans is estimated to have occurred about 3564 years ago. The mean substitution rate within human HAV full genomes under the same model was estimated to be 1.99 x 10(-4) substitutions/site/year. With this the mean age of genotype III strains was estimated to be 592 years while that of genotype IIIA was estimated to be 202 years. The time to the most common recent ancestor (tMRCA) of the Indian genotype IIIA isolates was calculated to be 116 years.

Chlorine decay studies in water supply system

Water supplied to the public through municipal water works should be qualitatively good and quantitatively sufficient. It is important that the potability of water is maintained at the consumer end. The presence of residual chlorine is invariably considered as an indicator of water quality. The chlorine consumption rate, which is categorized into bulk and wall reactions, governs the chlorine dosage given at the treatment plant. Bulk water chlorine reactions are system specific as water quality significantly affects the chlorine decay. The variability of chlorine reaction rates in different water qualities, viz. raw, sand filtered and distributed water from a real life water works, is studied in the present work. The potential applicability of two popular models, such as first order and two-component second order to represent the bulk water chlorine reactions, is evaluated. The range of reaction rate parameters involved in these models is also determined and it will help the modeller to choose appropriate values of input parameters while simulating water quality. The initial chlorine concentration also affects the reaction rates. The reaction rate parameters vary inversely with the initial chlorine concentration. Further, the repeated rechlorination studies carried out on sand filtered water show the reduction in chlorine consuming power of water.

The detection and characterization of hepatitis E virus in pig livers from retail markets of India

The zoonotic transmission of Hepatitis E virus (HEV) is a well-established fact and pigs are known reservoirs of the virus. The human and swine HEV from countries such as the USA, Japan and Taiwan, show a remarkable sequence identity. Swine liver samples from markets in Japan and US were shown to be HEV RNA positive. In contrast, in India, viruses belonging to different genotypes, that is, genotypes 1 and 4 circulate in humans and pigs respectively, at least for the last 20 years. To assess possible exposure of the Indian population to swine HEV, 240 pig liver samples were collected from retail markets of Pune, western India. Two (0.83%) samples were found positive for HEV RNA by nested RT-PCR. Nucleotide sequence-based phylogenetic analysis showed the presence of genotype 4 HEV with 90-91% similarity and clustering with Indian swine HEV sequences generated earlier. The data suggest the possibility of HEV infection in persons consuming infected pig liver. So far, it has not been possible to detect any type 4 HEV infection in humans. The absence of type 4 infections in humans may be attributed to cooking leading to the inactivation of the virus.

A novel technique of total laparoscopic hysterectomy for routine use: evaluation of 140 cases

Hysterectomy is one of the most commonly performed gynecological procedures. Although the first laparoscopic hysterectomy was performed in 1989, this technique accounts for only a few of all hysterectomies performed today. To assess the safety of total laparoscopic hysterectomy through a novel technique that we have evolved, a retrospective analysis of 140 patients with benign uterine pathologies operated at our institute between 2004 and 2007 was performed. All patients underwent total laparoscopic hysterectomy (TLH) using a simple technique. The highlight of this technique was the omission of any vaginal manipulator. The mean operation time was 88.75 ± 52.72 minutes, the mean blood loss 53.80 ± 35.94 ml and the mean hospital stay 2.21 ± 1.12 days. No conversion to open surgery was necessary. Iatrogenic complications were bowel injury (n=1) and vaginal tears (n=3) and were managed laparoscopically. The new method of TLH proved to be reproducible and safe with decreased morbidity and operation time. This can be attributed to the performance of the same standardized steps each time. Our technique provides a safe procedure suitable for routine use in gynecological surgery.

Entomological evaluation of malaria vectors at different altitudes in Hai district, northeastern Tanzania

Entomological monitoring in four villages situated along an altitude transect in the Hai District of Northeastern Tanzania identified Anopheles arabiensis Patton as the principal vector of malaria and detected seasonal changes in vector behavior. Over a 13-mo sampling period, 10,557 mosquitoes were collected with CDC light traps, pyrethrum spray catches, and pit traps of which 5,969 (56.5%) wereAn. arabiensis, 762 (7.2%) wereAnopheles funestus Giles s.l., 3,578 (33.9%) were culicines, and 248 (2.3%) were nonvector anophelines. Vector densities declined rapidly with increasing altitude, demonstrating a 50% decrease in annual human biting rate for every 86-m rise in altitude. Light traps were found to be more efficient than spray catches for the collection of An. arabiensis. This observation was attributed to increased exophily of this species, most notably in the wet season, and is supported by seasonal changes in the human blood index and fed/gravid ratio. These results indicate that spray catches may underestimate the abundance of exophilic vectors such as An. arabiensis and that entomological monitoring may require more than one collection method, especially at low vector densities. The annual entomological inoculation rate (EIR) decreased sharply with increasing altitude, with large variation around the estimate at low vector densities. Increased transmission because of unpredictable short rains at low altitudes and spatial clustering of infective mosquitoes may contribute to elevated EIR estimates.