Treatment planning for patients with low rectal cancer in a multicenter prospective organ preservation study

Background Non-surgical management of rectal cancer relies on (chemo)radiotherapy as the definitive treatment modality. This study reports and evaluates the clinical high dose radiotherapy treatment plans delivered to patients with low resectable rectal cancer in a Danish multicenter trial. Methods The Danish prospective multicenter phase II Watchful Waiting 2 trial (NCT02438839) investigated definitive chemoradiation for non-surgical management of low rectal cancer. Three Danish centers participated in the trial and committed to protocol-specified treatment planning and delivery requirements. The protocol specified a dose of 50.4 Gy in 28 fractions to the elective volume (CTV-/PTV-E) and a concomitant boost of 62 Gy in 28 fractions to the primary target volume (CTV-/PTV-T). Results The trial included 108 patients, of which 106 treatment plans were available for retrospective analysis. Dose coverage planning goals for the main target structures were fulfilled for 94% of the treatment plans. However, large intercenter differences in doses to organs-at-risk (OARs) were seen, especially for the intestines. Five patients had a V60Gy>10 cm3 for the intestines and two patients for the bladder. Conclusion Prescribed planning goals for target coverage were fulfilled for 94% of the treatment plans, however analysis of OAR doses and volumes indicated intercenter variations. Dose escalation to 62 Gy (as a concomitant boost to the primary tumor) introduced no substantial high dose volumes (>60 Gy) to the bladder and intestines. The treatment planning goals may be used for future prospective evaluation of highdose radiotherapy for organ preservation for low rectal cancer

Consequences of long-term growth at various [CO2] and temperatures on gas exchange of western wheatgrass(C3) and blue grama (C4

Continually rising atmospheric CO2 concentrations and possible climatic change may cause significant changes in plant communities. This study was undertaken to investigate gas exchange in two important grass species of the short-grass steppe, Pascopyrum smithii (western wheat-grass), C3, and Bouteloua gracilis (blue grama), C4, grown at different CO2 concentrations and temperatures. Intact soil cores containing each species were extracted from grasslands in north-eastern Colorado, USA, placed in growth chambers, and grown at combinations of two CO2 concentrations (350 and 700 μmol mol−1) and two temperature regimes (field average and elevated by 4°C). Leaf gas exchange was measured during the second, third and fourth growth seasons. All plants exhibited higher leaf CO2 assimilation rates (A) with increasing measurement CO2 concentration, with greater responses being observed in the cool-season C3 species P. smithii. Changes in the shape of intercellular CO2 response curves of A for both species indicated photosynthetic acclimation to the different growth environments. The photosynthetic capacity of P. smithii leaves tended to be reduced in plants grown at high CO2 concentrations, although A for plants grown and measured at 700μmol mol−1 CO2 was 41% greater than that in plants grown and measured at 350 μmol mol−1 CO2. Low leaf N concentration may have contributed to photosynthetic acclimation to CO2. A severe reduction in photosynthetic capacity was exhibited in P. smithii plants grown long-term at elevated temperatures. As a result, the potential response of photosynthesis to CO2 enrichment was reduced in P. smithii plants grown long-term at the higher temperature

Hemangiosarcoma of the nictitant membrane in a Brazilian Fila dog: case report Hemangiosarcoma em membrana nictitante de cão da ração Fila Brasileiro: relato de caso

It was reported a case of a 9-year-old Brazilian Fila male dog that had been affected by a tissular formation of the nictitant membrane of the right eye with four months of evolution. Conjunctival hyperemia and edema, serosanguinolent secretion, and a conjunctival neoformation at the nictitant membrane were observed. Surgical exeresis of the neoformation was performed. Endothelial cells slightly differentiated and pleomorphic, with an intense vascular neoformation compatible to nictitant membrane hemangiosarcoma, were found at the histological exam.<br>Relata-se o caso de um cão, macho, da raça Fila Brasileiro, com nove anos de idade, acometido por neoformação tecidual na membrana nictitante do olho direito, com cerca de quatro meses de evolução. Realizou-se exame oftálmico rotineiro, a partir do qual se notaram hiperemia e edema conjuntivais, secreção ocular serossangüinolenta e neoformação saliente na conjuntiva da membrana nictitante. Realizou-se a exérese cirúrgica da neoformação. À histopatologia, encontraram-se células endoteliais pouco diferenciadas e pleomórficas que originavam intensa neoformação vascular, compatíveis com hemangiossarcoma da membrana nictitante