Dose verification of volumetric modulated arc therapy (VMAT) by use of in-treatment linac parameters.

Linac parameters such as the multi-leaf collimator (MLC) position and jaw position, cumulative monitor units (MUs), and the corresponding gantry angle were recorded during the clinical delivery of volumetric modulated arc therapy for prostate, lung, and head/neck cancer patients. Then, linac parameters were converted into the beam-data format used in the treatment planning system, and the dose distribution was reconstructed. The dose-volume histogram and the dose difference (DD) were compared with the corresponding values in the treatment plan.

Serial measurement of free light chain detects poor response to therapy early in three patients with multiple myeloma who have measurable M-proteins.

Free light chain (FLC) assays are important in the diagnosis and monitoring of patients with multiple myeloma (MM). Serum FLC concentrations also correlate with disease course in the majority of MM patients and have been incorporated into the new response criteria. Although baseline values of FLC are prognostic in newly diagnosed MM, serial measurement of serum FLC does not appear to be of greater value in patients who have measurable M-proteins by electrophoresis.

Quality assurance of volumetric modulated arc therapy using Elekta Synergy.

PURPOSE. Recently, Elekta has supplied volumetric modulated arc therapy (VMAT) in which multi-leaf collimator (MLC) shape, jaw position, collimator angle, and gantry speed vary continuously during gantry rotation. A quality assurance procedure for VMAT delivery is described.

Cysteine-derived s-protected oxazolidinones: potential chemical devices for the preparation of peptide thioesters.

[reaction: see text]. An N-S acyl-transfer-mediated preparation of peptide thioesters using the S-protected oxazolidinone derived from cysteine has been developed and applied to the synthesis of a 32-mer biologically active peptide by native chemical ligation protocols.

New rapid enzyme-linked immunosorbent assay to detect antibodies against bacterial surface antigens using filtration plates.

An easy and rapid ELISA system, Filtration ELISA, to detect antibodies against bacterial cell surface antigens was developed using a 96-well filtration plate fitted with a 0.22microm membrane (MultiScreen-GV, Millipore). Bacterial whole cells were used as antigens without fixing the cells with formalin etc.