Electron intensity modulation for mixed-beam radiation therapy with an x-ray multi-leaf collimator

The current standard treatment for head and neck cancer at our institution uses intensity-modulated x-ray therapy (IMRT), which improves target coverage and sparing of critical structures by delivering complex fluence patterns from a variety of beam directions to conform dose distributions to the shape of the target volume. The standard treatment for breast patients is field-in-field forward-planned IMRT, with initial tangential fields and additional reduced-weight tangents with blocking to minimize hot spots. For these treatment sites, the addition of electrons has the potential of improving target coverage and sparing of critical structures due to rapid dose falloff with depth and reduced exit dose. In this work, the use of mixed-beam therapy (MBT), i.e., combined intensity-modulated electron and x-ray beams using the x-ray multi-leaf collimator (MLC), was explored. The hypothesis of this study was that addition of intensity-modulated electron beams to existing clinical IMRT plans would produce MBT plans that were superior to the original IMRT plans for at least 50% of selected head and neck and 50% of breast cases. Dose calculations for electron beams collimated by the MLC were performed with Monte Carlo methods. An automation system was created to facilitate communication between the dose calculation engine and the treatment planning system. Energy and intensity modulation of the electron beams was accomplished by dividing the electron beams into 2x2-cm2 beamlets, which were then beam-weight optimized along with intensity-modulated x-ray beams. Treatment plans were optimized to obtain equivalent target dose coverage, and then compared with the original treatment plans. MBT treatment plans were evaluated by participating physicians with respect to target coverage, normal structure dose, and overall plan quality in comparison with original clinical plans. The physician evaluations did not support the hypothesis for either site, with MBT selected as superior in 1 out of the 15 head and neck cases (p=1) and 6 out of 18 breast cases (p=0.95). While MBT was not shown to be superior to IMRT, reductions were observed in doses to critical structures distal to the target along the electron beam direction and to non-target tissues, at the expense of target coverage and dose homogeneity. ^

Systematic interpretation of molecular beacon polymerase chain reaction for identifying rpoB mutations in Mycobacterium tuberculosis isolates with mixed resistant and susceptible bacteria

Detection of multidrug-resistant tuberculosis (MDR-TB), a frequent cause of treatment failure, takes 2 or more weeks to identify by culture. RIF-resistance is a hallmark of MDR-TB, and detection of mutations in the rpoB gene of Mycobacterium tuberculosis using molecular beacon probes with real-time quantitative polymerase chain reaction (qPCR) is a novel approach that takes ≤2 days. However, qPCR identification of resistant isolates, particularly for isolates with mixed RIF-susceptible and RIF-resistant bacteria, is reader dependent and limits its clinical use. The aim of this study was to develop an objective, reader-independent method to define rpoB mutants using beacon qPCR. This would facilitate the transition from a research protocol to the clinical setting, where high-throughput methods with objective interpretation are required. For this, DNAs from 107 M. tuberculosis clinical isolates with known susceptibility to RIF by culture-based methods were obtained from 2 regions where isolates have not previously been subjected to evaluation using molecular beacon qPCR: the Texas–Mexico border and Colombia. Using coded DNA specimens, mutations within an 81-bp hot spot region of rpoB were established by qPCR with 5 beacons spanning this region. Visual and mathematical approaches were used to establish whether the qPCR cycle threshold of the experimental isolate was significantly higher (mutant) compared to a reference wild-type isolate. Visual classification of the beacon qPCR required reader training for strains with a mixture of RIF-susceptible and RIF-resistant bacteria. Only then had the visual interpretation by an experienced reader had 100% sensitivity and 94.6% specificity versus RIF-resistance by culture phenotype and 98.1% sensitivity and 100% specificity versus mutations based on DNA sequence. The mathematical approach was 98% sensitive and 94.5% specific versus culture and 96.2% sensitive and 100% specific versus DNA sequence. Our findings indicate the mathematical approach has advantages over the visual reading, in that it uses a Microsoft Excel template to eliminate reader bias or inexperience, and allows objective interpretation from high-throughput analyses even in the presence of a mixture of RIF-resistant and RIF-susceptible isolates without the need for reader training.^

An Hebrew grammar, collected chiefly from those of Mr. Israel Lyons, teacher of Hebrew in the University of Cambridge; and the Rev. Richard Grey, D.D. rector of Hinton, in Northamptonshire: To which is subjoined a praxis, taken from the sacred classics, and containing a specimen of the whole Hebrew language: with a sketch of the Hebrew poetry

as retrieved by Bishop Hare ...

Taylor's sacred minstrel, or, American church music book : a new collection of psalm and hymn tunes adapted to the various metres now in use : together with anthems, sentences, chants and other pieces : for the use of choirs, congregations, singing schools, musical societies, social sacred music circles, and private devotion ... /

Mode of access: Internet.

Symphony no. 3 : in C minor, Opus 78, for orchestra with organ /

Mode of access: Internet.

Concerto no. VII in G, for violin with accompaniment of orchestra, op. 76 /

"Edition for violin and piano."--Cover.

The redemption : a sacred trilogy /

For solo voices (SATB), chorus (SATB) and orchestra; English and French words.

A pagan poem : (after Virgil) composed for orchestra with piano, English horn and three trumpets obligato /

Mode of access: Internet.

Missa solemnis in D, for four solo voices, chorus and orchestra, opus 123. Vocal score,

Mode of access: Internet.

A dissertation on the right and obligation of the civil magistrate to take care of the interest of religion, and provide for its support; in which the arguments in confirmation of said right and obligation, both from reason and the Sacred Scriptures, are adduced: the usual objections examined,--together with several corollaries deduced from the subject.

A manual of Freemasonry : with an explanatory introduction to the science, and a free translation of some of the sacred scripture names /

Publisher's advertisements on front lining papers.

Rudiments of modern geography; with an appendix, containing an outline of sacred geography, problems on the use of the globes, and directions for the construction of maps. For the use of schools.

Mode of access: Internet.

The New Testament of our Lord and Saviour Jesus Christ : the text carefully printed from the most correct copies of the present authorized version including the marginal readings and parallel texts, with a commentary and critical notes, designed as a help to a better understanding of the sacred writings /

Spine title: Clarke's commentary, New Testament.