Feasibility study of multi-purpose quality assurance phantom for pretreatment verification of volumetric modulated arc therapy

Background: the purpose of this study was to evaluate the feasibility of a multipurpose quality assurance [QA] phantom for pretreatment verification of volumetric modulated arc therapy [VMAT]

Materials and Methods: the QA phantom was constructed with polymethyl methacrylate [PMMA] to perform relative dosimetry using EBT3 film and Map CHECK, as well as absolute dosimetry using an ionization chamber. The QA phantom was constructed to perform relative dosimetry using EBT3 film and Map CHECK, as well as the absolute dosimetry using ionization chamber. In order to verify the pretreatment plans, 25 patients treated with VMAT were selected. The pretreatment plans were calculated in the Eclipse treatment planning system using the Acuros XB dose calculation algorithm and CT images for the QA phantom, with the same beam setup and monitor units [MUs] as those for patient treatment. All plans were delivered to the Varian True Beam accelerator equipped with a high-definition multi-leaf collimator

Results: the multi-purpose QA phantom is developed for convenient VMAT dose verification. By using the QA phantom, all 25 cases passed +/- 3% acceptability criteria in absolute dosimetry with an ionization chamber for pretreatment verification. The relative dosimetry using EBT3 film and Map CHECK system also showed high agreement of more than 90% for 2%/2-mm and 3%/3-mm criteria

Conclusion: the results of this study demonstrated the good multipurpose capabilities of the phantom for the absolute and relative dosimetry. Therefore, the developed multi-purpose QA phantom was applied in our institution for routine VMRT dose verification

Hypoglycemic and hyperinsulinemic effects of some Egyptian herbs used for the treatement of diabetes mellitus [Type II] in rats

A group of 25 medicinal herbs, belonging to 13 different families, were assessed for their hypoglycemic and hyperinsulinemic action on alloxan diabetic rats. A dose of 1.5 ml of herb suspension/100 g b. wt. was orally administrated to alloxan diabetic rats for intervals of 4, 8 and 16 days. The results revealed that Lactuca virosa L. [Lebbein], Aloe perryi Baker [Sabir], Ambrosia maritima L. [Demissa], Artemisia arborescens L., [Shagaret mariam], Geranium robertianum L., [Requemoya], Cymbopogon proximus, [Half barr], Portulaca oleracea L., [Rigla], and Zygophyllum coccineum L., [Kammun karmani] exerted hypoglycemic effects after treatment for 16 days, and the results recorded were: 167, 193, 192, 189, 195, 198, 194, and 189 mg%, respectively. Some of these herbs exerted an increase in the level of serum insulin of diabetic rats especially Lactuca virosa L. [Lebbein], Petroselinum crispum, [Bagdouneas], Ambrosia maritima L., [Demissa], Geranium robertianum L. [Requemoya], Acacia nilotica L. [Sant], Lupinus albus L. [termes] and Portulaca oleracea L. [Rigla] after treatment for 16 days, and the results recorded were: 9.3, 8.9, 8.9, 10.2, 13.0, 8.9 and 10.4 muIU/ml, respectively. To identify the turnover for these herbs and to assess their physiological capability several investigations have been undertaken in the present work