Comparison of dose-volume analysis between standard Manchester plan and magnetic resonance image-based plan of intracavitary brachytherapy for uterine cervical cancer.

To investigate the feasibility of image-based intracavitary brachytherapy (IBICBT) for uterine cervical cancer, we evaluated the dose-volume histograms (DVHs) for the tumor and organs at risk (OARs) and compared results from the IBICBT plan and the standard Manchester system (Manchester plan) in eight patients as a simulation experiment. We performed magnetic resonance imaging (MRI) and computed tomography (CT) following MRI-adapted applicator insertion, then superimposed MR images on the planning CT images to describe the contours of high-risk clinical target volume (HR CTV) and OARs. The median volume of HR CTV was 29 cm(3) (range, 21-61 cm(3)). Median D90 (HR CTV) and V100 (HR CTV) were 116.1% prescribed doses (PD) (90.0-150.8%) and 96.7% (84.2-100%), respectively, for the Manchester plan. In comparison, we confirmed that the median D90 (HR CTV) was 100% PD in the IBICBT plan for all patients. Mean D(2cc) (bladder) was 101.8% PD for the Manchester plan and 83.2% PD for the IBICBT plan. Mean D(2cc) (rectum) was 80.1% PD for the Manchester plan and 64.2% PD for the IBICBT plan. Mean D(2cc) (sigmoid) was 75% PD for the Manchester plan and 57.5% PD for the IBICBT plan. One patient with a large tumor (HR CTV, 61 cm(3)) showed lower D90 (HR CTV) with the Manchester plan than with the IBICBT plan. The Manchester plan may represent overtreatment for small tumors but insufficient dose distribution for larger tumors. The IBICBT plan could reduce OAR dosage while maintaining adequate tumor coverage.

Method for rapid detection of the PvCesA3 gene allele conferring resistance to mandipropamid, a carboxylic acid amide fungicide, in Plasmopara viticola populations.

BACKGROUND: The occurrence of carboxylic acid amide (CAA)-fungicide-resistant Plasmopara viticola populations is becoming a serious problem in the control of grapevine downy mildew worldwide. RESULTS: The authors have developed a method, which utilises PCR-RFLP, for the rapid detection of resistance to the CAA fungicide mandipropamid in P. viticola populations. With this method, a glycine-to-serine substitution at codon 1105 of the cellulose synthase gene PvCesA3 of CAA-fungicide-resistant P. viticola was easily detected, although no resistant P. viticola was detected from 398 isolates in Japan. CONCLUSION: It is proposed that the PCR-RFLP method is a reliable tool for the rapid detection of CAA-fungicide-resistant P. viticola isolates. Only 4 h was required from the sampling of symptoms to the phenotyping of fungicide resistance.

Monitoring of QoI fungicide resistance in Plasmopara viticola populations in Japan.

BACKGROUND: The increasing occurrence of QoI fungicide resistance in Plasmopara viticola (Berk. & MA Curtis) Berl. & DeToni populations is becoming a serious problem in the control of grapevine downy mildew. In Japan, the existence of QoI-fungicide-resistant P. viticola was reported in 2009. RESULTS: The QoI fungicide resistance in P. viticola samples collected from vineyards in Japan in 2008 and 2009 was monitored. Resistant P. viticola were detected in the regions where QoI fungicides have been introduced in accordance with the pest management programme, whereas in Hokkaido vineyards, where QoI fungicides have not yet been introduced, QoI-fungicide-resistant P. viticola were not found. CONCLUSION: Japan comprises thousands of islands and is physically isolated from other countries by the sea. Monitoring the emergence, incidence and distribution of QoI fungicide resistance in P. viticola populations in Japan is necessary to improve pest management strategies for downy mildew disease in Japanese vineyards.

A dose-volume analysis of magnetic resonance imaging-aided high-dose-rate image-based interstitial brachytherapy for uterine cervical cancer.

PURPOSE: To investigate the feasibility of our novel image-based high-dose-rate interstitial brachytherapy (HDR-ISBT) for uterine cervical cancer, we evaluated the dose-volume histogram (DVH) according to the recommendations of the Gynecological GEC-ESTRO Working Group for image-based intracavitary brachytherapy (ICBT). METHODS AND MATERIALS: Between June 2005 and June 2007, 18 previously untreated cervical cancer patients were enrolled. We implanted magnetic resonance imaging (MRI)-available plastic applicators by our unique ambulatory technique. Total treatment doses were 30-36 Gy (6 Gy per fraction) combined with external beam radiotherapy (EBRT). Treatment plans were created based on planning computed tomography with MRI as a reference. DVHs of the high-risk clinical target volume (HR CTV), intermediate-risk CTV (IR CTV), and the bladder and rectum were calculated. Dose values were biologically normalized to equivalent doses in 2-Gy fractions (EQD(2)). RESULTS: The median D90 (HR CTV) and D90 (IR CTV) per fraction were 6.8 Gy (range, 5.5-7.5) and 5.4 Gy (range, 4.2-6.3), respectively. The median V100 (HR CTV) and V100 (IR CTV) were 98.4% (range, 83-100) and 81.8% (range, 64-93.8), respectively. When the dose of EBRT was added, the median D90 and D100 of HR CTV were 80.6 Gy (range, 65.5-96.6) and 62.4 Gy (range, 49-83.2). The D(2cc) of the bladder was 62 Gy (range, 51.4-89) and of the rectum was 65.9 Gy (range, 48.9-76). CONCLUSIONS: Although the targets were advanced and difficult to treat effectively by ICBT, MRI-aided image-based ISBT showed favorable results for CTV and organs at risk compared with previously reported image-based ICBT results.

Rapid method for detecting resistance to a QoI fungicide in Plasmopara viticola populations.

BACKGROUND: The increasing occurrence of Qo inhibitor (QoI)-fungicide-resistant Plasmopara viticola (Berk. & MA Curtis) Berl. & DeToni populations is becoming a serious problem in the control of grapevine downy mildew worldwide. RESULTS: The authors have developed a rapid method for detecting resistance to a QoI fungicide, azoxystrobin, in P. viticola populations using the nested PCR-RFLP method. With this method, a glycine-to-alanine substitution was discovered at codon 143 in the cytochrome b gene of P. viticola populations found in Japan. CONCLUSION: It is proposed that the nested PCR-RFLP method is a high-speed, sensitive and reliable tool for detecting azoxystrobin-resistant P. viticola populations.