Diversity of interferon inducible Mx gene in horses and association of variations with susceptibility vis-à-vis resistance against equine influenza infection

Equine influenza (EI) is primarily an infection of the upper respiratory tract and is one of the major infectious respiratory diseases of economic importance in equines. Re-emergence of the disease, species jumping by H3N8 virus in canines and possible threat of human pandemic due to the unpredictable nature of the virus have necessitated research on devising strategies for preventing the disease. The myxovirus resistance protein (Mx) has been reported to confer resistance to Orthomyxo virus infection by modifying cellular functions needed along the viral replication pathway. Polymorphisms and differential antiviral activities of Mx gene have been reported in pigs and chicken. Here we report the diversity of Mx gene, its expression in response to stimulation with interferon (IFN) α/β and their association with EI resistance and susceptibility in Marwari horses. Blood samples were collected from horses declared positive for equine influenza and in contact animals with a history of no clinical signs. Mx gene was amplified by reverse transcription from total RNA isolated from peripheral blood mononuclear cells (PBMCs) stimulated with IFN α/β using gene specific primers. The amplified gene products from representative samples were cloned and sequenced. Nucleotide sequences and deduced amino acid sequences were analyzed. Out of a total 24 amino acids substitutions sorting intolerant from tolerant (SIFT) analysis predicted 13 substitutions with functional consequences. Five substitutions (V67A, W123L, E346Y, N347Y, S689N) were observed only in resistant animals. Evolutionary distances based on nucleotide sequences with in equines ranged between 0.3-2.0% and 20-24% with other species. On phylogenetic analysis all equine sequences clustered together while other species formed separate clades.

HCl yield and chemical kinetics study of the reaction of Cl atoms with CH3I at the 298K temperature using the infra-red tunable diode laser absorption spectroscopy

Pulsed ArF excimer laser (193 nm)-CW infrared (IR) tunable diode laser Herriott type absorption spectroscopic technique has been made for the detection of product hydrochloric acid HCl. Absorption spectroscopic technique is used in the reaction chlorine atoms with methyl iodide (Cl+CH3I) to the study of kinetics on reaction Cl+CH3I and the yield of (HCl). The reaction of Cl+CH3I has been studied with the support of the reaction Cl+C4H10 (100% HCl) at temperature 298 K. In the reaction Cl+CH3I, the total pressure of He between 20 and 125 Torr at the constant concentration of [CH3I] 7.0×10(14) molecule cm(-3). In the present work, we estimated adduct formation is very important in the reaction Cl+CH3I and reversible processes as well and CH3I molecule photo-dissociated in the methyl [CH3] radical. The secondary chemistry has been studied as CH3+CH3ICl = product, and CH3I+CH3ICl = product2. The system has been modeled theoretically for secondary chemistry in the present work. The calculated and experimentally HCl yield nearly 65% at the concentration 1.00×10(14) molecule cm(-3) of [CH3I] and 24% at the concentration 4.0×10(15) molecule cm(-3) of [CH3I], at constant concentration 4.85×10(12) molecule cm(-3) of [CH3], and at 7.3×10(12) molecule cm(-3) of [Cl]. The pressure dependent also studied product of HCl at the constant [CH3], [Cl] and [CH3I]. The experimental results are also very good matching with the modelling work at the reaction CH3+CH3ICl = product (k = (2.75±0.35)×10(-10) s(-1)) and CH3I+CH3ICl = product2 (k = 1.90±0.15)×10(-12) s(-1). The rate coefficients of the reaction CH3+CH3ICl and CH3I+CH3ICl has been made in the present work. The experimental results has been studied by two method (1) phase locked and (2) burst mode.

Potentiometric Studies On Mixed Ligand Complexes

Potentiometric evidences have been cited for the formation of 1:1:1, ternary complexes in the systems La (III) -NTA-Hydroxy acids (where hydroxy acids = malic, tartaric, 1-hydroxy 2-naphthoic and 2-hydroxy-3 naphthoic acids).

Virulence Characterization of International Collections of the Wheat Stripe Rust Pathogen, Puccinia striiformis f. sp. tritici

Wheat stripe rust (yellow rust [Yr]), caused by Puccinia striiformis f. sp. tritici, is an economically important disease of wheat worldwide. Virulence information on P. striiformis f. sp. tritici populations is important to implement effective disease control with resistant cultivars. In total, 235 P. striiformis f. sp. tritici isolates from Algeria, Australia, Canada, Chile, China, Hungary, Kenya, Nepal, Pakistan, Russia, Spain, Turkey, and Uzbekistan were tested on 20 single Yr-gene lines and the 20 wheat genotypes that are used to differentiate P. striiformis f. sp. tritici races in the United States. The 235 isolates were identified as 129 virulence patterns on the single-gene lines and 169 virulence patterns on the U.S. differentials. Virulences to YrA, Yr2, Yr6, Yr7, Yr8, Yr9, Yr17, Yr25, YrUkn, Yr28, Yr31, YrExp2, Lemhi (Yr21), Paha (YrPa1, YrPa2, YrPa3), Druchamp (Yr3a, YrD, YrDru), Produra (YrPr1, YrPr2), Stephens (Yr3a, YrS, YrSte), Lee (Yr7, Yr22, Yr23), Fielder (Yr6, Yr20), Tyee (YrTye), Tres (YrTr1, YrTr2), Express (YrExp1, YrExp2), Clement (Yr9, YrCle), and Compair (Yr8, Yr19) were detected in all countries. At least 80% of the isolates were virulent on YrA, Yr2, Yr6, Yr7, Yr8, Yr17, YrUkn, Yr31, YrExp2, Yr21, Stephens (Yr3a, YrS, YrSte), Lee (Yr7, Yr22, Yr23), and Fielder (Yr6, Yr20). Virulences to Yr1, Yr9, Yr25, Yr27, Yr28, Heines VII (Yr2, YrHVII), Paha (YrPa1, YrPa2, YrPa3), Druchamp (Yr3a, YrD, YrDru), Produra (YrPr1, YrPr2), Yamhill (Yr2, Yr4a, YrYam), Tyee (YrTye), Tres (YrTr1, YrTr2), Hyak (Yr17, YrTye), Express (YrExp1, YrExp2), Clement (Yr9, YrCle), and Compair (Yr8, Yr19) were moderately frequent (>20 to <80%). Virulence to Yr10, Yr24, Yr32, YrSP, and Moro (Yr10, YrMor) was low (≤20%). Virulence to Moro was absent in Algeria, Australia, Canada, Kenya, Russia, Spain, Turkey, and China, but 5% of the Chinese isolates were virulent to Yr10. None of the isolates from Algeria, Canada, China, Kenya, Russia, and Spain was virulent to Yr24; none of the isolates from Algeria, Australia, Canada, Nepal, Russia, and Spain was virulent to Yr32; none of the isolates from Australia, Canada, Chile, Hungary, Kenya, Kenya, Nepal, Pakistan, Russia, and Spain was virulent to YrSP; and none of the isolates from any country was virulent to Yr5 and Yr15. Although the frequencies of virulence factors were different, most of the P. striiformis f. sp. tritici isolates from these countries shared common virulence factors. The virulences and their frequencies and distributions should be useful in breeding stripe-rust-resistant wheat cultivars and understanding the pathogen migration and evolution.

Mie lidar observations of lower tropospheric aerosols and clouds

Mie lidar system is developed at Laser Science and Technology Centre, Delhi (28.38°N, 77.12°E) by using minimal number of commercially available off-the-shelf components. Neodymium Yttrium Aluminum Garnet (Nd:YAG) laser operating at 1064nm with variable pulse energies between 25 and 400 mJ with 10 Hz repetition rate and 7ns pulse duration is used as a transmitter and off-axis CASSEGRAIN telescope with 100mm diameter as a receiver. Silicon avalanche photodiode (Si-APD) module with built-in preamplifier and front-end optics is used as detector. This system has been developed for the studies of lower tropospheric aerosols and clouds. Some experiments have been conducted using this set up and preliminary results are discussed. The characteristics of backscattered signals for various transmitter pulse energies are also studied. Atmospheric aerosol extinction coefficient values are calculated using Klett lidar inversion algorithm. The extinction coefficient, in general, falls with range in the lower troposphere and the values lie typically in the range 7.5×10(-5) m(-1) to 1.12×10(-4) m(-1) in the absence of any cloud whereas this value shoots maximum up to 1.267×10(-3) m(-1) (peak extinction) in the presence of clouds.

Sociocultural factors and malaria in the desert part of Rajasthan, India

BACKGROUND & OBJECTIVES

Malaria is a new emerging problem of Indian Thar Desert. The study was attempted to find out some sociocultural factors associated with malaria transmission in this region and to supplement social solutions to ongoing malaria control efforts in the desert part of Rajasthan.

METHODS

Interview technique was used for data collection on pre-tested schedules. In all 30 households (15 from low socioeconomic group and the same number of households from the high socioeconomic group) in a village were selected following systematic random sampling technique. A total of 450 respondents were selected randomly in 15 villages of Jaisalmer district, Rajasthan.

RESULTS

One-third of the respondents had neither taken treatment for malaria nor took part in the vector control operations because they did not consider mosquito bites to be harmful and took malaria as a mild disease. Outdoor sleeping habits, sharing bed with children, uneasy and suffocation feeling in using mosquito bednets or any other protective device also contributed to the spread of malaria in the study villages.

INTERPRETATION & CONCLUSION

Community should be educated as a whole particularly the low socioeconomic group of people to bring changes in their beliefs, sociocultural and health practices to protect themselves from mosquito bites by using bednets, repellents and other devices, such as wire mesh screening of house doors and windows.

A comparative emission profile of an urban area in Madhya Pradesh, India

This paper emphasizes on mathematical and field work approach to diagnosing the environmental pollution for Indore, India. These applications are based on the time-series statistics and for three semi-industrial as well as residential areas. The generalized additive models finds as a best fit-model in terms of autocorrelation and reduction of over-dispersion. The interdisciplinary study works on the principal of pollutant source, meteorological parameters, pollutant types, emission rates and various chemical processes. Several chemical or industrial processes like iron and steel production, combustion of fossil fuels, biomass burning, thermal power plants are major polluter in most of the mega cities.

Major Gene Controls of Field Resistance to Spot Blotch in Wheat Genotypes 'Milan/Shanghai #7' and 'Chirya.3'

A number of exotic wheat (Triticum aestivum) genotypes resistant to spot blotch caused by Cochliobolus sativus are being used to improve the resistance of commercial cultivars in the warm regions of South Asia. The objective of the present study was to determine the inheritance of field resistance to spot blotch in two resistant (R) wheat genotypes, 'Chirya.3' and 'Milan/Shanghai #7' (MS#7), which were crossed to a susceptible (S) commercial cultivar, 'BL1473.' The two resistant genotypes also were crossed to determine allelic relationships for resistance between them. Spot blotch severity was recorded on the parents and on F₁, F₂, and F₃ progenies. The F₁ plants from the two crosses between susceptible and resistant genotypes had low disease severity like the resistant parents, indicating that resistance in Chirya.3 and MS#7 is conditioned by dominant gene action. The F₂ plants segregated in 3R:1S ratios, and the F_2:3 families showed the ratio of 1R:1S:2S, segregating for R and S, suggesting that resistance in the two resistant parents is conditioned by a single, dominant gene. The F₁ plants from the cross between the two resistant genotypes were resistant, whereas their F₂ progenies segregated in 15R:1S, suggesting that the resistance genes in MS#7 and Chirya.3 are nonallelic. These simply inherited sources of resistance could be useful for improving spot blotch resistance in the warm regions of South Asia and also may offer useful diversity to breeding programs for developing spot-blotch-resistant wheat cultivars in other regions.

A comparative study of air pollution in Indian cities

Rapid and unplanned industrialization and urbanization has resulted in the deterioration of India's air quality according to air-quality monitoring carried out in seven major Indian cities in industrial and residential areas between 1995 and 2000. Suspended particulate matter (SPM) levels in Indian cities are in the range 50 to 550 microg/m(3). NO(x) values are high in Delhi's residential areas, with values of 33 microg/m(3) in 1995 and 34.6 microg/m(3) in 2000, while in an industrial area values of 29.4 microg/m(3) were found in 1995, increasing to 33.7 microg/m(3) in 2000. SO(2) values are very high in Pune city, ranging from 43.3 microg/m(3) in residential to 43.69 microg/m(3) in an industrial area in 2000.

Treatment seeking behaviour of malaria patients in desert part of Rajasthan, India

Malaria remains to be the most important cause of morbidity and mortality in India and in many other tropical countries with approximately 2 to 3 million new cases arising every year. In spite of arid conditions prevailing in desert part of Rajasthan, malaria is a major public health problem. A longitudinal study on social determinants of malaria has been undertaken in different villages of Ramgarh PHC of Jaisalmer district, Rajasthan. The study aims to know treatment seeking behabiour of malaria patients in the desert communities which is significantly different than the non-desert part of India. Out of 60 villages, 12 villages and 573 malaria patients were selected randomly. Interview technique was used for data collection. Information was recorded on pre-tested schedules. Self diagnosis 423 (73.8%) was more common among the respondents and 443 (77.3%) had taken treatment at home with local herbal remedies as the first treatment action. Desert population was not used to laboratory test for the malaria diagnosis. Symptoms based treatment was practised. They used private and government health facilities for the treatment of malaria. Self diagnosis for malaria was common but practised more by the poorer households. A large part of the population did not complete the full course of malaria treatment as a result drug resistance was more common. They did not use the government health facility as a first step of malaria treatment. There is need for health education with campaign emphasizing the role of mosquitoes in malaria transmission and the need for prompt medical intervention. The use of Government health services for the diagnosis and treatment of malaria by the poor should be encouraged through appropriate information, education and communication (IEC) which on the long run will be more cost effective for desert population under the national malaria control programme.

Importance of socioeconomic status and tree holes in distribution of Aedes mosquitoes (Diptera: Culicidae) in Jodhpur, Rajasthan, India

Immature Aedes mosquitoes were found in domestic, peridomestic, and tree hole habitats within three socioeconomic strata of Jodhpur, a city within an arid area of Rajasthan, India, endemic for dengue. Peridomestic habitats served as a persistent source of Aedes vectors, especially those used for watering cows for religious reasons that were located within high socioeconomic areas. Domestic (indoor) containers within low socioeconomic strata showed a higher container index (27.0%) than periurban areas with cattle sheds (14.3%) or high socioeconomic areas (18.1%). Mosquitoes were collected in tree holes at zoos and gardens supporting several species of monkeys. Six of 67 Aedes albopictus Skuse reared from immatures collected in tree holes tested positive for dengue antigen acquired through vertical transmission, possibly indicating a persistence mechanism for dengue virus within an urban environment.

Study of social determinants of malaria in desert part of Rajasthan, India

BACKGROUND & OBJECTIVES

A longitudinal study on social determinants of malaria has been undertaken in different villages of Ramgarh PHC of Jaisalmer district, Rajasthan. The study aims to determine social determinants of malaria as applicable to existing cast groups of desert part of Rajasthan.

METHODS

Out of 940 households in five villages, 150 households of Rajput community (forward community) and Meghwal community (backward community) were selected at random to study whether due to different behaviour of existing caste groups, transmission of malaria and its intensity also vary or not.

RESULTS

It was found that magnitude of malaria was three times more in the Meghwal community as compared to Rajput community. In-migration of natives importing malaria was found to be prominent cause of more malaria incidence in the backward community.

INTERPRETATION & CONCLUSION

An intervention policy aiming to study existing status of knowledge among different caste groups of desert areas could lead to a substantial control over in-migration as well as further transmission of disease in the desert part of Rajasthan.

Effectiveness of fluoxetine in the treatment of skin-picking

The case of an 18-year-old girl with skin-picking is reported. The patient used to pick at healthy skin and small skin lesions, leading to ulceration, hyperpigmentation and disfigurement. She recovered almost fully with fluoxetine. The implications of diagnosis and the need for early treatment are discussed.

Epidemiology of foliar blights (spot blotch and tan spot) of wheat in the plains bordering the himalayas

ABSTRACT Helminthosporium leaf blight (HLB), a complex of spot blotch caused by Cochliobolus sativus and of tan spot caused by Pyrenophora tritici-repentis, is a major wheat disease in South Asia. This 2-year study elucidated HLB development and its impact on yield. Symptoms caused by C. sativus and P. tritici-repentis were first observed at the seedling and tillering stages, respectively. The number of airborne conidia and leaves infected by the two pathogens remained low for several weeks under lower temperatures, followed by a sharp rise as temperatures increased. The number of airborne conidia of C. sativus and incidence of infection by C. sativus were higher compared with P. tritici-repentis. The disease complex caused an average 30% reduction in yield, with greater losses under delayed seeding. Delayed seeding increased disease severity even in resistant genotypes and caused higher yield losses. 'Milan/Shanghai-7' was the most resistant among six genotypes evaluated. Despite higher disease severity, 'BL 1473' showed relatively lower yield losses, indicating its tolerance to foliar blight. The findings of this study bear implications for integrated foliar blight management in the warmer areas of South Asia by combining optimum seeding date, seed treatment and foliar spray of fungicides, and resistant wheat genotypes.

Entomological studies on malaria in irrigated and non-irrigated areas of Thar desert, Rajasthan, India

BACKGROUND & OBJECTIVES

Malaria is the major health problem in western Rajasthan yet its vector fauna and transmission dynamics thereof is not understood properly. The present investigations report complete profile of qualitative and quantitative aspects of anopheline species occurring in different settings of desert ecosystem.

METHODS

Area with irrigation through canal for more than 20 years (setting I), area with irrigation through canal for 10 years (setting II) and area without any irrigation (setting III) have been selected for studies. Species identification and their densities (per man hour) was made as per standard methods.

RESULTS

In village of setting I, during rainy season, An. subpictus and An. stephensi were present while during winter season four species--An. subpictus, An. stephensi, An. culicifacies and An. annularis were collected. In all the villages of setting I, II and III no Anopheles mosquito was observed during summer season. In the villages of desert region without any irrigation facilities through any canal, the anopheline species were present only during rainy season.

INTERPRETATION & CONCLUSION

An. stephensi is the major malaria vector of desert irrespective of whether the area is canal irrigated or not. During summer season absence of vector species in all the villages require further studies on micro-ecology of the species under desert conditions.

Cutaneous sporotrichosis in Himachal Pradesh, India

During the period 1990-2002 in Himachal Pradesh, India, 103 new patients with cutaneous sporotrichosis were detected. Lymphocutaneous and fixed cutaneous varieties were the most common and seen in 49% and 43% respectively. Chronic non-specific inflammation without granuloma formation was seen in 46% skin biopsy specimens, 29% showed acute or chronic inflammation and tuberculoid granuloma formation was seen in 25%. In 32% of cases Sporothrix schenckii growth was seen on Sabouraud glucose agar. A saturated solution of potassium iodide was used as first-line treatment and in 93% patients healing of lesions occurred in 4-32 weeks (average 8.7 weeks) without significant side-effects. Itraconazole, used in 12 patients, was highly effective in recommended doses. Rapid healing was seen with higher than previously used doses of fluconazole in one patient who also had unusual exacerbation of lesional inflammation with saturated solution of potassium iodide.

Status of Soil Transmitted Helminth infections in an urban locality of Assam; as observed from survey by WHO sampling methodology for school children and community survey by random sampling

In this study, an attempt was made to compare and correlate findings of a Soil Transmitted Helminths (STH) survey carried out using WHO sampling methodology for school children and community survey by random sampling. The prevalence and intensity of STH in the age-group of 9-10 yrs reportedly represent community status. The results showed that the STH prevalence and intensity in the age-group of 9-10 years do represent community burden. However, more such surveys will have to be carried out to substantiate this statement.

Sperm motion characteristics of Garole rams raised for a prolonged period in a semi-arid tropical environment

The Garole is a prolific but less well known and rare breed of small sheep found in the hot and humid Sunderban region of West Bengal. An ability to breed throughout the year and to graze in knee-deep water, resistance to foot rot and a strong mothering instinct are some of the special features of this breed. Garole rams could provide germplasm to incorporate prolificacy traits by artificial insemination of the nonprolific sheep breeds found in abundance in the semi-arid and arid tropical climates of India. The aim of the present study was to evaluate the semen production by Garole rams maintained in a semi-arid climate for three years and to objectively assess their semen quality by a computer-assisted sperm analysis technique. The donor rams were randomly selected each year from the original flock procured from their natural habitat or from the offspring born at the Institute farm. Semen was collected weekly for three weeks each autumn for three consecutive years from 8 rams each year. The overall means (SD) of the traits that did not differ significantly with age or year were volume, concentration, curvilinear velocity, average path velocity, amplitude of lateral head displacement, beat frequency, motility and the percentages of rapid motile sperms and of slow motile sperms. The age of the rams had a significant effect (p<0.05) on the straight-line velocity but this was not significantly affected by the length of exposure to the semi-arid climate. However, the age and year had significant effects (p<0.05) on linearity, straightness and the percentage of medium motile sperms. It was concluded that Garole rams are capable of producing good-quality semen even after a prolonged period of exposure to a semi-arid tropical climate.

Long term lung retention studies of 125Sb aerosols in humans

This paper describes the retention of 125Sb oxide aerosols in human lungs based on the data obtained from a group of seven accidental inhalation exposure cases. Long-term follow-up studies for periods of time ranging from 1 to 3 d post intake to 199 to 2,422 d post intake have indicated the biological lung clearance half-time of this material ranging from about 600 to 1,100 d for non-smokers and 1,700 to 3,700 d for smokers. The retention in the lungs after 180 d in all the seven cases is found to be much more than 51% of the estimated initial alveolar deposit, which is consistent with the present ICRP criteria of assignment to the lung absorption Type S. There is little previously reported human data on this radionuclide compound. In these studies reliable information on actual time of intake, the likely type of material, and the amount of retained body/lung activity in initial days after the incident was also available, which adds to the importance of these data. The results of these studies provide a basis for firm classification and suggest that oxides of antimony need to be removed from absorption Type M (earlier class W) where these are presently listed by ICRP and be placed in absorption Type S (earlier class Y). The range of measured retained lung activities after the initial rapid clearance phase (7 d post exposure) was about 3 to 14 kBq, which was sufficient for long-term follow up studies using the whole body counters.

A new focus of cutaneous leishmaniasis in Himachal Pradesh (India)

This paper highlights a new focus of cutaneous leishmaniasis (CL) in the temperate area of Himachal Pradesh (India), a previously non-endemic area. In this hospital-based study, 38 new cases of CL, acquired indigenously have been detected from 1988-2000. Of these, 26 were from Kinnaur district and 12 from adjoining areas of bordering districts situated along the river: Satluj. There were 18 males and 20 females. They were between 4-75 years of age and had the disease for one month to 2 years at the time of presentation. Face involvement was seen in majority of the patients. Nodulo-ulcerative plaque was the commonest lesion. Muco-cutaneous lesions were seen in four cases. Tissue smears and biopsies were positive for LD bodies in 61.7% and 29.4% cases respectively. Intralesional sodium stibogluconate produced a consistent therapeutic response. The possible mode of its introduction in the region is postulated. The reservoir of infection, identity of the vector at this altitude (9,002,900 meters above sea level) and the strain of leishmania, remain to be identified.

Spontaneously improving Michelin tire baby syndrome

Michelin tire syndrome is described in a 22-month-old girl of Indian origin who had generalized folding of the skin, esotropia, epicanthic folds, and delayed speech. Histopathology showed diffuse lipomatous hypertrophy. The skin changes showed partial improvement on follow-up. We report this case because of its rarity. Furthermore, the spontaneous improvement is significant, unlike the persistent course of other congenital nevi.

A computational study of the urinary excretion rates for 339Pu using new ICRP internal dosimetry models

A computational study of the urinary excretion rates for 239Pu has been carried out using a methodology which involved the solution of a complete compartmental model describing the biokinetic behaviour of inhaled plutonium aerosols in the human body. The methodology, after proper validation, was applied to investigate the dependence of urinary excretion rates for 239Pu on the transfer rates given in the complete compartmental model. For this purpose, the default values of the transfer/absorption rates were modified by factors of 2 and 4 and urinary excretion rates were computed on 1, 10, 100, 1000 and 10,000 d post-intake. The percentage variations in the urinary excretion rates as a result of the modified transfer rates were computed for exposures to Type M and S aerosols of 239Pu. These results facilitated the identification of parameters significantly affecting the short-term and long-term urinary excretion rates. In addition, time variations of the predicted ratios of 239Pu activity in daily urine to that in blood (excretion ratios) were studied for the three biokinetic models of plutonium: the ICRP 67 model, the modified ICRP 67 model with the compartment STI to urinary bladder removed and Luciani and Polig's model. All the computational results are presented and discussed in this paper.

Validation of biokinetic models of Cs and I using their daily dietary intakes and organ contents in an adult Indian population

The daily dietary intakes and total contents of Cs and I in skeletal muscle and thyroid, respectively, for an average Indian adult were estimated by determining their concentrations in the total cooked diet and tissue samples using instrumental neutron activation analysis. These data were then used to predict the biological half-lives of Cs and I and their radioactive counterparts for the Reference Indian Man. The predicted biological half-lives of Cs and I for Reference Indian Man were found to be comparable with the reported values for the ICRP Reference Man.

Assessing skull burdens of actinides using a mathematical phantom: a Monte Carlo approach

In vivo monitoring techniques are needed to estimate the amount of an actinide in the skeleton in addition to that in the lungs and liver. Skull counting with external detectors has been a standard procedure for this purpose. Realistic skull phantoms are normally used to calibrate the counting systems. However, the fabrication of realistic phantoms is extremely difficult and expensive. Therefore, a theoretical approach based on Monte Carlo methods in conjunction with a Cristy mathematical phantom has been examined for assessing skull burdens of actinides. A computer program that generates surface sources of actinides on the skull and simulates low-energy photon transport in the heterogeneous media of the head region of the Cristy phantom was developed for this purpose. The program determines the observable pulse height spectrum of the detector and the corresponding calibration factors for different counting geometries. The computer program was used to generate the pulse height spectra and the corresponding calibration factors of 20 cm and 15 cm diameter phoswich detectors, each positioned on the left and right sides and on the top of the head region of the Cristy phantom, whose skull surfaces were assumed to have a uniform distribution of 241Am. The computed calibration factor for a counting geometry consisting of three phoswich detectors (15 cm diameter each) surrounding the phantom's skull was found to be in excellent agreement with the experimental results obtained for the same geometry using a realistic physical skull phantom. This provided a validation of the realistic design of the skull in the Cristy phantom, implying that the results reported in this paper could be used for in vivo measurements of skull burdens of 241Am for the stated counting geometry.

Feasibility studies for assessing internal exposure to 233U

The potential internal occupational exposure encountered as a consequence of the 232Th-233U fuel cycle are likely to arise predominantly from the inhalation of 232Th, 233U and (232Th + 233U) compounds of absorption Types M and S. In the past, although direct and indirect methods for assessments of internal exposure to 232Th and its daughters were developed, standardised and employed, no such attempts have been made with regard to 233U and 233U + 232Th. Therefore, feasibility studies for assessing internal exposure to 233U have been conducted using three methods: urine bioassay, in vivo counting and measurement of thoron gas in the exhaled breath of a worker. This paper describes details of these studies and discusses the results obtained.

Persistence of dengue-3 virus through transovarial transmission passage in successive generations of Aedes aegypti mosquitoes

Progeny of Aedes aegypti mosquitoes infected intrathoracically with dengue-3 virus was reared to subsequent generations. In each generation, blood-fed females were confined individually and the eggs obtained from the transovarially infected females were pooled. The seventh generation obtained from the infected parental mosquitoes showed that virus could persist in mosquitoes in successive generations through transovarial passage. The rate of vertical transmission initially increased in the few generations (F1-F2), but in subsequent generations it was found to be steady. Parental mosquitoes inoculated with virus showed higher mortality than the diluent-inoculated controls. There was an increase in the larval duration of transovarially infected batches at the seventh generation when compared with uninfected control mosquitoes. The fecundity and fertility of the transovarially infected batches of mosquitoes was also affected when compared with the controls. This is the first report demonstrating persistence of dengue virus in the successive generations of mosquitoes infected through vertical transmission. These observations, which have great epidemiologic importance, suggest that vector mosquitoes may play an important role in the maintenance of virus in nature, and that mosquitoes may act as reservoirs of these viruses.

Bancroftian filariasis in Bagdogra town, district Darjeeling (West Bengal)

Filaria endemicity is probably gradually increasing over the years in Bagdogra town, district Darjeeling (West Bengal). Of 1511 night blood smears examined, 35 were found positive for Wuchereria bancrofti (mf rate 2.32%). The microfilaria (mf) rates for males and females were 2.84% and 1.79 % respectively. The age of these positives ranged from 5-45 years. The mf rate was highest (4.46%) in the age group of 20-29 years. All mf carriers were local residents of Bagdogra and Wuchereria bancrofti was only the infection encountered. Mean microfilaria density was 7.71 per 20 cmm. of blood, whereas Median microfilaria density (MFD50) was 21 per 20 cmm. of blood. Disease and filarial endemicity rates were 0.33% and 2.65% respectively. Ten man hour vector mosquito density ranged from 30 to 65. Out of 49 female Culex quinquefasciatus mosquitoes dissected for the presence of filaria infection, none was found positive for the infection. During 1976 survey in the same town, mf rate was 1.6% and disease rate was nil.

Ocular scrofuloderma with unilateral proptosis

Proptosis due to an extraconal orbital abscess of tubercular origin with lacrimal gland involvement, representing ocular scrofuloderma, is a rare entity. This association has not been reported earlier in the literature. We describe a 7-year-old boy who presented with nodulo-ulcerative lesions of tubercular etiology with discharging sinuses on right side of the face and a similar lesion on the right lower eyelid along with proptosis of 4 months duration. Computerized tomography (CT) scan of the head confirmed the extraconal, intraorbital, hyperdense, homogeneously enhancing mass separated from the lateral rectus muscle and further revealed involvement of lacrimal gland along with erosion of the temporal bone. The patient showed marked improvement of his dermatological and ophthalmological lesions with anti-tubercular treatment. Subsequent ultrasound examinations of the orbit revealed regression in the size of the abscess from 10.7 mm to 5.0 mm and then complete disappearance of the abscess obviating surgical intervention.

Breeding habitats and larval indices of Aedes aegypti (L) in residential areas of Rajahmundry town, Andhra Pradesh

Entomological studies on relative prevalence and distribution of adults and immatures of Aedes aegypti were conducted in Rajahmundry town of Andhra Pradesh from December 1998 to November 1999. Adults and immature stages of Aedes aegypti were found in all the 22 localities viz; posh area (8), mixed area (8) and slum area (6) of the town. Larval indices were found to be higher in slum areas as compared to mixed or posh areas of the town. However, the larval habitats were observed to be similar in all localities. The larval indices were highest during monsoon and post-monsoon months. The breeding preference ratio (BPR) was highest for cement tubs followed by discarded tyres and barrels. The high larval indices of Aedes aegypti in these areas warrant intensification of vector surveillance activities along with source reduction and health education.

Development of an automated shielded chair whole-body monitor

A standard shielded chair whole-body monitor has been developed as a computer controlled, unattended, walk-in-type of whole-body monitor for internal dosimetry of radiation workers. A radiation worker enters his personal computer code through the attached computer terminal and follows a few instructions on the screen. The chair door then opens automatically and after the worker has positioned himself into the counting geometry in the chair, the door closes. At the end of the whole-body monitoring for a pre-set time, the chair door opens again and the worker moves out. The monitoring data acquired on a 4K-MCA is saved in the computer memory automatically and the chair door closes again making it available for monitoring the next worker. The system also gives audio instructions to the worker to occupy the chair and to move out after the counting is over. A system supervisor can come at any convenient time and get a print out of the monitoring report in the standardised format or carry out any detailed analysis if required. The system has the software for calculating intakes and the committed effective doses using the latest ICRP methodologies, from the measured retained activities of the various important fission and activation products like 137Cs, 131I, 60Co, 125Sb etc. This type of system with trained staff is also expected to be of value in case of emergencies as a quick monitoring system.