Intra-cavity Photodynamic Therapy for malignant tumors of the paranasal sinuses: An in vivo light dosimetry study

Background: Photodynamic therapy (PDT) is a promising treatment option for recurrent sinonasal malignancies. However, light administration in this area is challenging given the complex geometry, varying tissue optical properties and difficult accessibility. The goal of this study was to estimate the temporal and spatial variation in fluence and fluence rate during sinonasal mTHPC-mediated PDT. It was investigated whether the predetermined aim to illuminate with a fluence of 20 J⋅cm−2 and fluence rate of 100 mW⋅cm−2 was achieved. Methods: In eleven patients the fluence and fluence rates were measured using in vivo light dosimetry at the target location during real-time sinonasal PDT. There was a variance in sinonasal target location and type of light diffuser used. In four patients two isotropic detectors were used within the same cavity. Results: All measurements showed major fluence rate fluctuations within each single isotropic detector probe over time, as well as between probes within the same cavity. The largest fluence rate range measured was 328 mW⋅cm−2. Only one probe showed a mean fluence rate of ∼100 mW⋅cm−2. Taken all probes together, a fluence rate above 80 mW⋅cm−2 was measured in 31 % of the total light exposure; in 22 % it was less than 20 mW⋅cm−2. Thirty-three percent showed a fluence of at least 20 J⋅cm−2. Conclusions: The current dosimetry approach for sinonasal intra-cavity PDT shows major temporal and spatial variations in fluence rate and a large variance in light exposure time. The results emphasize the need for improvement of in vivo light dosimetry and dosimetry planning

Meio de cultura, concentração de AIB e tempo de cultivo no enraizamento in vitro de amoreira-preta e framboeseira Culture environment, IBA concentration and cultivation time on in vitro rooting of blackberry and raspberry

A propagação da amoreira-preta e da framboeseira dá-se principalmente por meio de estacas de raiz e mesmo de hastes novas, contudo, já é crescente o interesse pelo uso da micropropagação como um método alternativo de propagação . O enraizamento é uma das etapas mais difícieis, onde a definição do meio de cultivo, da concentração ótima de AIB para o enraizamento, constitui um passo importante, por isso objetivou-se com este experimento determinar o melhor meio de cultivo, melhor tipo de cultivo e a melhor concentração de AIB no meio de cultura para o enraizamento in vitro da amoreira-preta 'Xavante' e de framboeseira 'Batum' e 'Heritage'. O material vegetal utilizado foram microestacas apicais com duas folhas, com cerca de 1 cm de comprimento, oriundas do cultivo in vitro. Os fatores estudados foram o tipo de meio de cultura MS e WPM - Wood Plant Media, a concentração de AIB no meio de cultura e o tempo de cultivo das microestacas em meio com AIB. O meio WPM, em concentrações baixas, menores de 3 µM de AIB, induziram maiores médias de enraizamento e comprimento. Concentrações altas de AIB induziram a formação de calo, para amoreira-preta, 'Xavante'. Para a framboeseira o meio WPM, com menores concentrações de AIB (0 e 3 µM), mostrou as melhores médias no número de raízes, comprimento de raízes e pequena intensidade de calo; com as maiores concentrações de AIB, ocorreu maior aparecimento de calo.<br>The propagation of blackberry and raspberry occur mainly through root cutting and even of softwoods stem; however, it is already increasing the interest for the use of the micropropagation as an alternative technique of vegetative propagation of fruit plants, since the rooting is one of the most difficult stages, in which the definition of both the culture environment and the best concentration of AIB for the rooting, is an important stage. For that purpose, the aim of this research was to determine the best cultivation type and the best concentration of IBA in the culture environment for the in vitro rooting of the blackberry 'Xavante' and the raspberry 'Batum' and 'Heritage'. The vegetable material used was atex microcutting with two leaves, measuring about 1 cm of length, originated from the in vitro cultivation. The studied factors were the kinds of culture (MS and WPM), the IBA concentration in the culture environment and the time of cultivation of the microcutting in an environment with IBA. The WPM environment, in low concentrations, less than 3 µM of IBA, together with T1, induced larger rooting averages and length. High concentrations of AIB induced the callus formation for blackberry 'Xavante'. For raspberry, using WPM environment with smaller concentrations of AIB (0 and 3 , µM), it was shown the best average in the number of roots, length of roots and small callus intensity, with the largest concentrations of IBA it happened larger callus emergence

Technological (R)Evolution leads to detection of more sentinel nodes in patients with melanoma in the head and neck region

Background Sentinel lymph node (SN) biopsy (SLNB) has proven to be a valuable tool for staging melanoma patients. Since its introduction in the early 1990s, this procedure has undergone several technological refinements, including the introduction of single photon emission computed tomography combined with computed tomography (SPECT/CT) as well as radio- and fluorescence-guidance. The purpose of the current study was to evaluate the effect of this technological evolution on SLNB in the head and neck region. Primary endpoint was the false-negative (FN) rate. Secondary endpoints were number of harvested SNs, overall operation time, operation time per harvested SN and postoperative complications. Patients and Methods A retrospective database was queried for cutaneous head and neck melanoma patients who underwent SLNB at The Netherlands Cancer Institute between 1993 and 2016. The implementation of new detection techniques was divided in 4 groups: (1) 1993-2005, with preoperative lymphoscintigraphy and intraoperative use of both a gamma ray detection probe and patent blue (n=30); (2) 2006-2007, with addition of preoperative roadmaps based on SPECT/CT (n=15); (3) 2008-2009, with intraoperative use of a portable gamma camera (n=40); and (4) 2010-2016, with the addition of near-infrared fluorescence guidance (n=192). Results A total of 277 patients were included. At least one SN was identified in all patients. A tumor-positive SN was found in 59 patients (21.3%), 10 in group 1 (33.3%), 3 in group 2 (20.0%), 6 in group 3 (15.0%) and 40 in group 4 (20.8%). Regional recurrences of patients with tumor-negative SNs resulted in an overall FN rate of 11.9% (FN groups 1: 16.7%; 2: 0%; 3: 14.3%; 4: 11.1%). The number of harvested nodes increased with advancing technologies (p=0.003) whereas Breslow thickness and operation time per harvested SN decreased (p=0.003 and p=0.017, respectively). There was no significant difference in percentage of tumor-positive SNs, overall operation time and complication rate between the different groups. Conclusion The use of advanced detection technologies led to a higher number of identified SNs without increase in overall operation time, which may indicate an improved surgical efficiency. Operation time per harvested SN decreased, the average FN rate remained 11.9% and unchanged over 23 years. There was no significant change in postoperative complication rate