Changing Trends and Experience with Esophageal Cancer Surgery in a Single University Hospital: Are The Results Similar or Not?

Objective: The main treatment modality for esophageal cancer remains to be surgery. Over the last decades, surgical strategies have evolved remarkably. When neoadjuvant chemoradiotherapy became standard, discussions about the role, type, and timing of surgery began. In this study, we share results we obtained after operating our patients using various surgical techniques.Material and Methods:Reliable data from 51 esophageal cancer patients were evaluated retrospectively. Of the 51 cases, 31 were operable. These operable cases were further classified according to surgical method and neoadjuvant therapy status. Median survival time in months, complications, hospital mortality, length of hospital stay, and pathology results (total lymph nodes harvested and pathologic tumor node metastasis stage [p_TNM]) were documented for the different surgical approaches.Results: Open surgical methods were performed in 21 cases, while in 10 cases the Minimally Invasive Surgery (MIS) method was used. The MIS group received neoadjuvant therapy more frequently than the open surgical methods group (p=0.013). Although more complications were observed in the MIS group, the difference to the open esophagectomy methods group was not significant. Patients in the MIS group also had longer hospital stays, but again the difference was not significant. Although a pathologic complete response was seen in 8 of the 11 (72.7%) patients in our study who received chemoradiotherapy as neoadjuvant treatment, the surgical results of patients who received chemoradiotherapy were worse, although not to a statistically significant extent.Conclusion: Despite changing trends and treatment options in esophageal cancer surgery, we have yet to see the expected improved results

Effect of Levodopa on Reward and Impulsivity in a Rat Model of Parkinson's Disease

The use of dopamine replacement therapies (DRT) in the treatment of Parkinson's disease (PD) can lead to the development of dopamine dysregulation syndrome (DDS) and impulse control disorders (ICD), behavioral disturbances characterized by compulsive DRT self-medication and development of impulsive behaviors. However, the mechanisms behind these disturbances are poorly understood. In animal models of PD, the assessment of the rewarding properties of levodopa (LD), one of the most common drugs used in PD, has produced conflicting results, and its ability to promote increased impulsivity is still understudied. Moreover, it is unclear whether acute and chronic LD therapy differently affects reward and impulsivity. In this study we aimed at assessing, in an animal model of PD with bilateral mesostriatal and mesocorticolimbic degeneration, the behavioral effects of LD therapy regarding reward and impulsivity. Animals with either sham or 6-hydroxydopamine (6-OHDA)-induced bilateral lesions in the substantia nigra pars compacta (SNc) and ventral tegmental area (VTA) were exposed to acute and chronic LD treatment. We used the conditioned place preference (CPP) paradigm to evaluate the rewarding effects of LD, whereas impulsive behavior was measured with the variable delay-to-signal (VDS) task. Correlation analyses between behavioral measurements of reward or impulsivity and lesion extent in SNc/VTA were performed to pinpoint possible anatomical links of LD-induced behavioral changes. We show that LD, particularly when administered chronically, caused the development of impulsive-like behaviors in 6-OHDA-lesioned animals in the VDS. However, neither acute or chronic LD administration had rewarding effects in 6-OHDA-lesioned animals in the CPP. Our results show that in a bilateral rat model of PD, LD leads to the development of impulsive behaviors, strengthening the association between DRT and DDS/ICD in PD.Portuguese Foundation for Science and Technology: Ciência 2007 Program and IF Development Grant (IF/00111/2013) to AJS, Portuguese Foundation for Science and Technology PhD scholarships attributed to MMC (SFRH/BD/51061/2010), FLC (SFRH/BD/47311/2008) and CS-C (SFRH/BD/51992/2012), and Post-Doctoral Fellowship to HL-A (SFRH/BPD/80118/2011). Neurochemical analysis was funded from ELKE/UOA: 11650. This article has been developed under the scope of the project NORTE-01-0145-FEDER-000013 and NORTE-01-0145-FEDER-000023, supported by the Northern Portugal Regional Operational Programme (NORTE 2020), under the Portugal 2020 Partnership Agreement, through the European Regional Development Fund (FEDER). This work has been funded by FEDER funds, through the Competitiveness Factors Operational Programme (COMPETE), and by National funds, through the Foundation for Science and Technology (FCT), under the scope of the project POCI-01-0145-FEDER-007038info:eu-repo/semantics/publishedVersio

Experimental research and ANN modeling on the impact of the ball burnishing process on the mechanical properties of 5083 Al-Mg material

5083 Al-Mg is the widely used material in food, chemistry, vehicle, machinery, and construction sectors, as well as in the aviation and space industries. The burnishing is normally used as the finishing operation for this material with the advantages such as surface roughness, reduced fracture formation, hardness, fatigue strength, and an increase of the wear resistance. These positive improvements are dependent on burnishing process parameters such as feed rate, burnishing force, ball diameter, and a number of revolutions. The study contains determination and optimization of the machining parameters and their effects on the surface roughness, microhardness, and the strength of 5083 Al-Mg material in the ball burnishing processes. Multiple regression and ANOVA analysis were performed to identify significant process parameters. A new Artificial Neural Networks (ANN) model with different neuron structures and algorithms has also been developed using experimental results to supplement the multiple regression model as the desired R-2 values could not be achieved with the latter. The ANOVA analysis indicated that both the burnishing force and the number of revolutions have a significant effect on the surface roughness and hardness with optimums 300 N and 200 rpm, respectively. Results from the two models were compared with each other. The developed ANN model is shown to estimate the surface roughness and the surface hardness with high reliability (R-2 = 0.999992) without costly experimental trials