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Human papillomavirus (HPV) is the well-known second most cause of cervical cancer in women worldwide. According to the WHO survey, 70% of the total cervical cancers are associated with types HPV 16 and 18. Presently used prophylactic vaccine for HPV contains mainly capsid protein of L1 virus like particles (VLPs). Correct folding of VLPs and display of neutralizing epitopes are the major constraint for VLP-based vaccines. Further, monoclonal antibodies (mAbs) play a vital role in developing therapeutics and diagnostics. mAbs are also useful for the demonstration of VLP conformation, virus typing and product process assessment as well. In the present study, we have explored the usefulness of mAbs generated against sf-9 expressed HPV 16 VLPs demonstrated as type-specific and conformational dependent against HPV 16 VLPs by ELISA. High affinity and high pseudovirion neutralization titer of mAbs indicated their potential for the development of prophylactic vaccines for HPV. Also, the type-specific and conformational reactivity of the mAbs to HPV 16 VLPs in sf-9 cells by immunofluorescence assay proved their diagnostic potential.

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Chikungunya fever, a re-emerging RNA viral infection produces different cutaneous manifestations in children compared to adults. 52 children with chikungunya fever, confirmed by positive IgM antibody test were seen during 2009-2010. Pigmentary lesions were common (27/52) followed by vesiculobullous lesions (16/52) and maculopapular lesions (14/52). Vesiculobullous lesions were most common in infants, although rarely reported in adults. Psoriasis was exacerbated in 4 children resulting in more severe forms. In 2 children, guttate psoriasis was observed for the first time.

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Underdosing of treatment targets can occur in radiation therapy due to electronic disequilibrium around air-tissue interfaces when tumors are situated near natural air cavities. These effects have been shown to increase with the beam energy and decrease with the field size. Intensity modulated radiation therapy (IMRT) and tomotherapy techniques employ combinations of multiple small radiation beamlets of varying intensities to deliver highly conformal radiation therapy. The use of small beamlets in these techniques may therefore result in underdosing of treatment target in the air-tissue interfaces region surrounding an air cavity. This work was undertaken to investigate dose reductions near the air-water interfaces of 1x1x1 and 3x3x3 cm(3) air cavities, typically encountered in the treatment of head and neck cancer utilizing radiation therapy techniques such as IMRT and tomotherapy using small fields of Co-60, 6 MV and 15 MV photons. Additional investigations were performed for larger photon field sizes encompassing the entire air-cavity, such as encountered in conventional three dimensional conformal radiation therapy (3DCRT) techniques. The EGSnrc/DOSXYZnrc Monte Carlo code was used to calculate the dose reductions (in water) in air-water interface region for single, parallel opposed and four field irradiations with 2x2 cm(2) (beamlet), 10x2 cm(2) (fan beam), 5x5 and 7x7 cm(2) field sizes. The magnitude of dose reduction in water near air-water interface increases with photon energy; decreases with distance from the interface as well as decreases as the number of beams are increased. No dose reductions were observed for large field sizes encompassing the air cavities. The results demonstrate that Co-60 beams may provide significantly smaller interface dose reductions than 6 MV and 15 MV irradiations for small field irradiations such as used in IMRT and tomotherapy.

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Cobalt-60 (Co-60) based radiation therapy continues to play a significant role in not only developing countries, where access to radiation therapy is extremely limited, but also in industrialized countries. Howver, technology has to be developed to accommodate modern techniques, including image guided and adaptive radiation therapy (IGART). In this paper we describe some of the practical and clinical considerations for Co-60 based tomotherapy by comparing Co-60 and 6 MV linac-based tomotherapy plans for a head and neck (HandN) cancer and a prostate cancer case. The tomotherapy IMRT plans were obtained by modeling a MIMiC binary multi-leaf collimator attached to a Theratron-780c Co-60 unit and a 6 MV linear accelerator (CL2100EX). The EGSnrc/BEAMnrc Monte Carlo (MC) code was used for the modeling of the treatment units with the MIMiC collimator and EGSnrc/DOSXYZnrc code was used for beamlet dose data. An in-house inverse treatment planning program was then used to generate optimized tomotherapy dose distributions for the H and N and prostate cases. The dose distributions, cumulative dose area histograms (DAHs) and dose difference maps were used to evaluate and compare Co-60 and 6 MV based tomotherapy plans. A quantitative analysis of the dose distributions and dose-volume histograms shows that both Co-60 and 6 MV plans achieve the plan objectives for the targets (CTV and nodes) and OARs (spinal cord in HandN case, and rectum in prostate case).

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Recent investigations demonstrate a strong potential for Cobalt-60 (Co-60)-based tomotherapy. Reported work suggests that Co-60-based tomotherapy offers a clinically and commercially viable alternative to megavoltage x-ray-based tomotherapy. Tomotherapy applications use a combination of intensity-modulated fan beams to deliver highly conformal radiotherapy. However, conventional Co-60 units are designed to give large uniform rectangular fields using an isotropic radioactive source in a cylindrical geometry. Such cylindrical source geometry likely provides a sub-optimal use of the radioactivity within the source volume for tomotherapy applications due to a significant loss of radiated energy outside the fan beam collimation system. To investigate a more efficient source geometry suitable for Co-60 tomotherapy applications, a computer code was written to model an isotropic source in a 6-faced polyhedron geometry such as cube, parallelepiped, prism and truncated pyramid. This code was integrated with the existing EGSnrc/BEAMnrc Monte Carlo (MC) code. The integrated source code was thoroughly tested, validated and used to investigate the energy spectra, radiation output and self-shielding properties of various rectangular-shaped (RS) Co-60 sources. Fan beam dose profiles were calculated for various cylindrical and RS Co-60 sources for a range of source-to-axis distances (SAD), multi-leaf collimator-to-isocentre distances (CID) and modified collimator systems. Fringe and penumbra distances were analysed for the simulated dose profiles. Our results demonstrate that clinically acceptable fringe and penumbra distances can be achieved by a careful selection of SAD, CID, source shape and dimensions and modified collimator system. Significant overall gain in radiation output of the 20 x 1 cm(2) fan beams can be achieved by an optimal selection of the source geometry for a given active volume of Co-60. The overall gain includes the effects of change in packing density (accounting for self-absorption) and change in source shape.

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The ontogeny of photosensitivity has been studied in a holometabolous insect, the midge Chironomus ramosus. The life cycle of midges shifts from an aquatic environment to a non-aquatic environment. Extracellular electrical activity of photoreceptor organs was recorded at larval and adult stages. We found an increase in photosensitivity as the larva metamorphosed to the adult stage. This is the first report of changes in photosensitivity during the development of any insect described in an ecological context.

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Time-disposition studies are necessary for computing energy requirements of populations. This study captures the rich information on the timed activity pattern of adult women from poor households engaged in home-based work. We studied 34 women beedimakers (cigarette makers), 21 tailors, and 34 homemakers. Data were collected by direct observation of the women's activities on a typical day. Time spent on related activities was pooled and classified as sleep, household work, child care, occupational work, and residual work. These were further categorized on the basis of our published work on the energy cost of women's activities and the World Health Organization (WHO) classification of occupational activities as sedentary, moderate, and heavy. Most of the household activities could be classified as moderate to heavy (> 2.2 times basal metabolic rate [BMR]). Childcare activities were distributed on a scale from sedentary to heavy, whereas occupational activities, such as beedimaking and tailoring, were sedentary (< 2.2 BMR). Homemakers spent significantly more time on moderate to heavy work (p < .05) than beedimakers and tailors. Women working for income spent only four to six hours on occupational work, which was possible because they reduced the time spent on heavy work (i.e., housework), and reduced the time on personal care. Still, more than 80% of women could not put in eight hours of paid work. Thus, women in the home-based sector constantly negotiate among time spent on heavy household work, child care, and occupational work in order to continue in the labor market.

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The FBX aqueous chemical dosimeter contains 0.2 mol m(-3) ferrous ammonium sulphate, 5.0 mol m(-3) benzoic acid and 0.20 mol m(-3) xylenol orange in 40.0 mol m(-3) sulphuric acid. The dosimeter can measure photon and electron doses in the range 0.1 to 3000 cGy in radiotherapy. The response of this dosimeter was measured for a 53.2 MeV carbon beam in the present work. Our initial result indicates that the sensitivity of the FBX system to the carbon beam as compared to cobalt-60 gamma rays is 25.5%, and thus we believe that the FBX system could be a useful dosimeter for carbon beams and similar heavy ions considered useful in radiotherapy.

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OBJECTIVE: To study the maternal child-rearing behaviors, parental attributes and socio-economic status of the family and to analyze their association with positive deviance in the developmental status of preschool children between 1-5 years of age. DESIGN: Cross-sectional. SETTING: Rural community. METHODS: A total of 260 children and their mothers were evaluated. Weight and height-for-age indices were used to assess growth. ICMR Developmental Screening Test was used to assess psychosocial development. Bhatia's Performance Test was used to assess maternal intelligence. Narayan Rao's Rating Scale was used to assess socio-economic status and a child-rearing interview schedule developed and pretested for the purpose of the study to assess maternal child-rearing practices and behaviors. RESULTS: Stepwise multiple regression with psychosocial development as dependent variable indicated significant associations between specific maternal behavioral categories and psychosocial development of 1-5 year old children. Children, whose mothers were responsive to their needs, were consistent in their interaction with them and were also emotionally stable during specific child rearing situations were those identified as "positive deviants" with regard to their development. Other factors, which were significantly associated with positive deviance in children, were paternal literacy and nuclear type of family. Significant differences were observed between genders. CONCLUSIONS: The data generated from the study could identify the important factors that were associated with "positive deviance" in the development of children. These factors can be useful components for parental counseling in clinical practice and as educational material in community programmes such as the ICDS and self-help groups at the village level.

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OBJECTIVE: To assess the psychosocial development of well nourished and malnourished children aged 0-6 years and to identify the microenvironmental factors influencing their growth and development. DESIGN: Multicentric cross-sectional. SETTING: Rural Communities. SUBJECTS: Total of 3668 children of whom 2212 were well nourished and 1456 were malnourished. METHODS: Weight for age index to assess nutritional status. Cut-off < 75% NCHS standards used based on Gomez grades II and III being malnourished and Normal and grade I being well nourished. ICMR Developmental Screening Test to assess psychosocial development and modified WHO parental interview schedule to assess family and micro-environmental factors. RESULTS: Malnourished children attained developmental milestones at a later age. Developmental delay among the malnourished was especially observed in areas like vision and fine motor, language and comprehension and personal social. The delay was to the extent of 7-11 months in these areas in different age groups. Paternal involvement with child care especially, father spending time, telling stories and taking child for outing was found to be important for positive psychosocial development. Other significant factors included parents teaching child, small family size and paternal occupation. Child's appetite, absence of health problems, parental age and family having own house and electricity were the factors significantly related to better nutritional status of children. CONCLUSION: Factors identified in the study are important for the development of relevant intervention at the home level. Appropriate multifaceted community based programmes such as the ICDS are also required for stimulating growth and development of backward rural children.

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A multicentric cross-sectional collaborative study was undertaken in 3 centres in India with the main aim of developing simple and reliable indicators for the early detection of developmental disabilities in children under 6 years of age and to compare the age of attainment of developmental milestones in children in the three regions. The study provided a simple low-cost and culture-appropriate psychosocial developmental screening test battery which can be used with ease by trained public health grass-roots functionaries. This instrument was standardized on a large rural, tribal and urban sample comprising more than 13,000 children from 3 regions in India. The procedure for sampling, selection of items and methodology for standardization of the instrument in the Hyderabad region detailed in this paper were replicated in other centres as well. Quality control of data was ensured through inter-rater and test-retest measures of reliability. During pre-testing, 66 culture-appropriate milestones were selected finally from a larger item pool. The 50th centile age reference values of the Hyderabad study children and those obtained by other 2 centres were comparable.

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A modification of water oxidation complex in spinach chloroplasts by rose bengal (RB), a known histidine modifying agent, has been studied using thermoluminescence (TL) technique. The changes in the TL profiles at low concentrations of the dye are explained on the basis of alterations in the protein dynamics while those at higher concentrations of the dye are related to the oxidation of histidine residues.

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Inhibition of photosystem II (PS II) activity by 8-hydroxyquinoline (8-HQ) has been investigated in case of spinach chloroplasts and isolated photosystem II particles using the thermoluminescence technique. In presence of 8-HQ, water to methylviologen (MV) photoreduction in isolated chloroplasts is inhibited while the reduction of dichlorophenol indophenol is inhibited in both chloroplasts as well as in photosystem II particles. The activity can be restored fully by addition of diphenylcarbazide (DPC), suggesting that the donor side of water oxidation complex is affected. The changes in the thermoluminescence peaks indicate that the charge recombination processes involving S2 or S3 states of the Kok's cycle are probably affected by 8-HQ treatment.

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Compound action potentials recorded from normal and M. leprae infected mice sciatic nerves were analysed in frequency domain using Fourier Series Analysis. Changes in myelinated fibre potentials were detected as early as 2nd post-inoculation month. This technique could be further developed to aid in early diagnosis of leprosy.

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A study of the sciatic nerve compound action potential was carried out, in normal and non-immunosuppressed swiss mice (white) inoculated with 5000 M. leprae in each hind foot pad, from 1st to 7th post-inoculation month. In normal mice, the threshold for stimulation, maximum amplitude, duration and conduction velocity of all the three components of the compound action potential were measured. Progressive changes were noted in amplitude and the threshold for stimulations of the unmyelinated fibre ('C' fibres) potentials. These changes were compared with the changes observed in the myelinated fibre potentials.

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Non-immunosuppressed Swiss mice inoculated with 5000 M. leprae in each hind foot pad were subjected to nerve conduction velocity studies followed by light and electron microscopy and fibre tease of both sciatic nerves at sequential time intervals from the 4th to the 24th month. The conduction velocity was standardized for basal temperature of 35 degrees C and uninoculated mice were used as controls. Progressive changes were noted in conduction velocity from the 6th post inoculation month and correlated with the ultrastructural changes which were first observed at the 4th month. Fibre teasing showed predominent segmental demyelination.

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