Interobserver variation in rectal and bladder doses in orthogonal film-based treatment planning of cancer of the uterine cervix

Orthogonal film-based treatment planning is the most commonly adopted standard practice of treatment planning for cancer of the uterine cervix using high dose rate brachytherapy (HDR). This study aims at examining the variation in rectal and bladder doses when the same set of orthogonal films was given to different observers. Five physicists were given 35 pairs of orthogonal films obtained from patients who had undergone HDR brachytherapy. They were given the same instructions and asked to plan the case assuming the tumor was centrally placed, using the treatment-planning system, PLATO BPS V13.2. A statistically significant difference was observed in the average rectal (F = 3.407, P = 0.01) and bladder (F = 3.284, P = 0.013) doses and the volumes enclosed by the 100% isodose curve (P < 0.01) obtained by each observer. These variations may be attributed to the differences in the reconstruction of applicators, the selection of source positions in ovoids and the intrauterine (IU) tube, and the differences in the selection of points especially for the rectum, from lateral radiographs. These variations in planning seen within a department can be avoided if a particular source pattern is followed in the intrauterine tube, unless a specific situation demands a change. Variations in the selection of rectal points can be ruled out if the posterior vaginal surface is clearly seen

Detection and characterisation of a begomovirus associated with leaf curl disease of ornamental croton (Codiaeum variegatum)

A leaf curl disease was observed on croton (Codiaeum variegatum L.), a popular ornamental plant in botanical, home, and office gardens in and around Bengaluru, South India. Diseased plants showed typical symptoms of vein thickening, severe inward curling and a reduction in leaf size, and stunting. The pathogen responsible was transmitted to healthy croton plants by grafting of infected scions, and through the whitefly vector, Bemisia tabaci, suggesting that the disease was caused by a begomovirus. The association of a begomovirus with the disease was further confirmed by the amplification of viral DNA fragments of ca. 520 bp and 575 bp derived from the coat protein (CP) gene of DNA-A using degenerate primers and total DNA extracted from infected, but not from healthy croton plants. The 575 bp fragment corresponding to the core region of the CP gene was cloned and sequenced. Phylogenetic analysis of the core CP sequence grouped the croton-infecting begomovirus, which we tentatively called croton leaf curl virus (CrLCuV), with Ageratum yellow vein virus (AJ810825), with which it shared the highest nucleotide identity (95%). The core CP sequence was similar (90 – 95%) to many other begomoviruses from the Indian sub-continent that infect tomato, tobacco, cotton, and papaya. Thus, its precise taxonomic denomination will require sequencing of the complete ssDNA viral genome