42 research outputs found
Magnetic resonance imaging (MRI) in rectal cancer: a comprehensive review
Magnetic resonance imaging (MRI) has established itself as the primary method for local staging in patients with rectal cancer. This is due to several factors, most importantly because of the ability to assess the status of circumferential resection margin. There are several newer developments being introduced continuously, such as diffusion-weighted imaging and imaging with 3Â T. Assessment of loco-regional lymph nodes has also been investigated extensively using different approaches, but more work needs to be done. Finally, evaluation of tumours during or after preoperative treatment is becoming an everyday reality. All these new aspects prompt a review of the most recent advances and opinions. In this review, a comprehensive overview of the current status of MRI in the loco-regional assessment and management of rectal cancer is presented. The findings on MRI and their accuracy are reviewed based on the most up-to-date evidence. Optimisation of MRI acquisition and relevant regional anatomy are also presented, based on published literature and our own experience
Evaluation of skin absorption of drugs from topical and transdermal formulations
ABSTRACT The skin barrier function has been attributed to the stratum corneum and represents a major challenge in clinical practice pertaining to cutaneous administration of drugs. Despite this, a large number of bioactive compounds have been successfully administered via cutaneous administration because of advances in the design of topical and transdermal formulations. In vitro and in vivo evaluations of these novel drug delivery systems are necessary to characterize their quality and efficacy. This review covers the most well-known methods for assessing the cutaneous absorption of drugs as an auxiliary tool for pharmaceutical formulation scientists in the design of drug delivery systems. In vitro methods as skin permeation assays using Franz-type diffusion cells, cutaneous retention and tape-stripping methods to study the cutaneous penetration of drugs, and in vivo evaluations as pre-clinical pharmacokinetic studies in animal models are discussed. Alternative approaches to cutaneous microdialysis are also covered. Recent advances in research on skin absorption of drugs and the effect of skin absorption enhancers, as investigated using confocal laser scanning microscopy, Raman confocal microscopy, and attenuated total reflectance Fourier-transform infrared spectroscopy, are reviewed
RISE - Reuse im Software Engineering. Evaluationsmethodik der Kontextermittlung
Das Projekt RISE beschĂ€ftigt sich mit der Wiederverwendung (Reuse) im Bereich Software Engineering. Dieser Report dient dazu, die Methodik zu beschreiben mit welcher der Kontext (d.h. der Ist-Zustand) bei den Anwendungspartnern ermittelt wird. Dazu wird in diesem Report die Planung sowie Zielsetzung beschrieben und Unterlagen zur Evaluation der Infrastruktur in Software-Unternehmen geliefert. Ergebnisse der durchgefĂŒhrten Kontextermittlung bei den beiden Anwendungspartnern im RISE Projekt - brainbot technologies AG und empolis - werden in einem weiteren Report veröffentlicht. Ebenso wird eine Verschriftlichung der Interviews und Gruppendiskussionen bei den Anwendungspartnern in einem eigenstĂ€ndigen und vorlĂ€ufig geheimen Report veröffentlicht
Prostate cancer and elective nodal radiation therapy for cN0 and pN0-a never ending story? : Recommendations from the prostate cancer expert panel of the German Society of Radiation Oncology (DEGRO).
For prostate cancer, the role of elective nodal irradiation (ENI) for cN0 or pN0 patients has been under discussion for years. Considering the recent publications of randomized controlled trials, the prostate cancer expert panel of the German Society of Radiation Oncology (DEGRO) aimed to discuss and summarize the current literature. Modern trials have been recently published for both treatment-naĂŻve patients (POP-RT trial) and patients after surgery (SPPORT trial). Although there are more reliable data to date, we identified several limitations currently complicating the definitions of general recommendations. For patients with cN0 (conventional or PSMA-PET staging) undergoing definitive radiotherapy, only men with high-risk factors for nodal involvement (e.g., cT3a, GS â„âŻ8, PSA â„âŻ20âŻng/ml) seem to benefit from ENI. For biochemical relapse in the postoperative situation (pN0) and no PSMA imaging, ENI may be added to patients with risk factors according to the SPPORT trial (e.g., GS â„âŻ8; PSA >âŻ0.7âŻng/ml). If PSMA-PET/CT is negative, ENI may be offered for selected men with high-risk factors as an individual treatment approach
Proton or photon irradiation for hemangiomas of the choroid? A retrospective comparison
Abstract Purpose To compare on a retrospective basis the results of therapy in patients with uveal hemangioma treated with photon or proton irradiation at a single center. Methods From 1993 to 2002 in total 44 patients were treated. Until 1998 radiotherapy was given with 6 MV photons in standard fractionation of 2.0 Gy five times a week. In 1998 proton therapy became available and was used since then. A dose of 20 22.5 CGE Cobalt Gray Equivalent 68 MeV protons were given on four consecutive days. Progressive symptoms or deterioration of vision were the indications for therapy. Results Of the total of 44 patients treated, 36 had circumscribed choroidal hemangiomas CCH and 8 had diffuse hemangiomas DCH and Sturge Weber syndrom. 19 patients were treated with photons with a total dose in the range of 16 30 Gy. 25 patients were irradiated with protons. All but one patient with DCH were treated with photons. Stabilization of visual acuity was achieved in 93.2 of all patients. Tumorthickness decreased in 95.4 and retinal detachment resolved in 92.9 . Late effects although in general mild or moderate, were detected frequently. 40.9 showed radiation induced optic neuropathy RON maximum grade I. Retinopathy was found in 29.5 , but only one patient experienced more than grade II. Retinopathy and RON were reversible in some of the patients and in part resolved completely. No differences could be detected between CCH patients treated with protons and photons. Treatment was less effective in DCH patients 75 Conclusions Radiotherapy is effective in treating choroidal hemangiomas with respect to visual acuity and tumor thickness but a benefit of proton therapy could not be detected. Side effects are moderate but careful monitoring for side effects should be part of the follow up procedure
Role of indoleamine 2,3-dioxygenase in testicular immune-privilege
International audienceMale meiotic germ cell including the spermatozoa represent a great challenge to the immune system, as they appear long after the establishment of normal immune tolerance mechanisms. The capacity of the testes to tolerate autoantigenic germ cells as well as survival of allogeneic organ engrafted in the testicular interstitium have led to consider the testis an immunologically privileged site. Disruption of this immune privilege following trauma, tumor, or autoimmune orchitis often results in male infertility. Strong evidence indicates that indoleamine 2,3-dioxygenase (IDO) has been implicated in fetal and allograft tolerance, tumor immune resistance, and regulation of autoimmune diseases. IDO and tryptophan 2,3-dioxygenase (TDO) catalyze the same rate-limiting step of tryptophan metabolism along a common pathway, which leads to tryptophan starvation and generation of catabolites collectively known as kynurenines. However, the relevance of tryptophan metabolism in testis pathophysiology has not yet been explored. Here we assessed the in vivo role of IDO/TDO in experimental autoimmune orchitis (EAO), a model of autoimmune testicular inflammation and immunologically impaired spermatogenesis. EAO was induced in adult Wistar rats with testicular homogenate and adjuvants. Control (C) rats injected with saline and adjuvants and normal untreated rats (N) were also studied. mRNA expression of IDO decreased in whole testes and in isolated Sertoli cells during EAO. TDO and IDO localization and level of expression in the testis were analyzed by immunostaining and Western blot. TDO is expressed in granulomas from EAO rats, and similar protein levels were observed in N, C, and EAO groups. IDO was detected in mononuclear and endothelial cells and reduced IDO expression was detected in EAO group compared to N and C rats. This phenomenon was concomitant with a significant reduction of IDO activity in EAO testis measured by tryptophan and kynurenine concentrations (HPLC). Finally, in vivo inhibition of IDO with 1-methyl-tryptophan increased severity of the disease, demonstrating down regulation of IDO-based tolerance when testicular immune regulation was disrupted. We present evidence that an IDO-based mechanism is involved in testicular immune privilege
Preischemic efferent vagal stimulation increases the size of myocardial infarction in rabbits. Role of the sympathetic nervous system
The vagal nerve stimulation (VNS) has been tested for the treatment of chronic heart failure in humans (Schwartz et al., 2008). However, many of the effects of parasympathetic stimulation in ischemic heart disease are still unknown. Kawada et al. have shown a significant increase in acetylcholine (Ach) levels in the ventricular myocardium subjected to VNS (Kawada et al., 2000). Since, Ach has been implicated in the mechanism of ischemic preconditioning (Yellon & Downey, 2003), we can hypothesize that VNS applied before ischemia may reduce myocardial infarct size by a release of Ach. However, under certain experimental conditions, the two divisions of the autonomic nervous system (sympathetic and parasympathetic) can be activated. Therefore, co-activation of the sympathetic nervous system could generate a situation adverse and contrary to the possible beneficial effect expected for VNS.Fil: Buchholz, Bruno. Universidad de Buenos Aires. Facultad de Medicina. Instituto de FisiopatologĂa Cardiovascular; Argentina. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Oficina de CoordinaciĂłn Administrativa Houssay. Instituto de BioquĂmica y Medicina Molecular. Universidad de Buenos Aires. Facultad Medicina. Instituto de BioquĂmica y Medicina Molecular; ArgentinaFil: Donato, Pablo MartĂn. Universidad de Buenos Aires. Facultad de Medicina. Instituto de FisiopatologĂa Cardiovascular; Argentina. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Oficina de CoordinaciĂłn Administrativa Houssay. Instituto de BioquĂmica y Medicina Molecular. Universidad de Buenos Aires. Facultad Medicina. Instituto de BioquĂmica y Medicina Molecular; ArgentinaFil: Perez, MarĂa Virginia. Universidad de Buenos Aires. Facultad de Medicina. Instituto de FisiopatologĂa Cardiovascular; Argentina. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Oficina de CoordinaciĂłn Administrativa Houssay. Instituto de BioquĂmica y Medicina Molecular. Universidad de Buenos Aires. Facultad Medicina. Instituto de BioquĂmica y Medicina Molecular; ArgentinaFil: Ivalde, Flavio C.. Universidad de Buenos Aires. Facultad de Medicina. Instituto de FisiopatologĂa Cardiovascular; ArgentinaFil: Höcht, Christian. Universidad de Buenos Aires. Facultad de Farmacia y BioquĂmica; ArgentinaFil: Buitrago, Emiliano. Universidad de Buenos Aires. Facultad de Farmacia y BioquĂmica; ArgentinaFil: RodrĂguez, Manuel. Universidad de Buenos Aires. Facultad de Medicina. Instituto de FisiopatologĂa Cardiovascular; ArgentinaFil: Gelpi, Ricardo Jorge. Universidad de Buenos Aires. Facultad de Medicina. Instituto de FisiopatologĂa Cardiovascular; Argentina. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Oficina de CoordinaciĂłn Administrativa Houssay. Instituto de BioquĂmica y Medicina Molecular. Universidad de Buenos Aires. Facultad Medicina. Instituto de BioquĂmica y Medicina Molecular; Argentin
Enantioselective pharmacokinetics and cardiovascular effects of nebivolol in L-NAME hypertensive rats
The cardiovascular effects and pharmacokinetics of nebivolol were assessed in N(G)-nitro-l-arginine methyl ester (L-NAME) hypertensive and normotensive control rats. Male Wistar rats were randomly divided to drink tap water (control) or L-NAME solution for 2 weeks. The effects of nebivolol (3 or 10âmgâkgâ1 i.v.) on blood pressure (BP), heart rate and BP variability (BPV) were recorded in awake L-NAME and control rats. Short-term and beat-to-beat BPV was assessed by the s.d. and spectral analysis of the BP recordings. Nebivolol pharmacokinetics was studied by means of traditional blood sampling. Nebivolol showed enantioselective pharmacokinetics in both experimental groups; the clearance and the volume of distribution of l-nebivolol were significantly greater than those of the d-enantiomer. The hypotensive response to nebivolol was significantly enhanced in L-NAME rats (Îmean arterial pressure (MAP): â16.1±1.1%, P<0.05 vs. control rats) compared with normotensive animals (ÎMAP: â1.4±2.1%). An analysis of the beat-to-beat BPV showed a greater reduction in VLF BPV in the L-NAME compare with the control rats. Nebivolol significantly reduced the low-frequency/high-frequency ratio in hypertensive L-NAME animals compared with normotensive rats. Short-term BPV was markedly reduced by nebivolol in both experimental groups, although the attenuation of the s.d. of BP recording was greater in L-NAME rats. In conclusion, the hypotensive efficacy of nebivolol is significantly enhanced in L-NAME rats compared with normotensive animals, which is most likely due to a greater reduction in vascular sympathetic activity. Nebivolol markedly attenuated short-term BPV in both experimental groups, suggesting that ÎČ-blockers with additional pharmacological actions provide beneficial cardiovascular effects by controlling high BP and its short-term variability.Fil: Bertera, Facundo Martin. Universidad de Buenos Aires. Facultad de Farmacia y BioquĂmica. Departamento de FarmacologĂa; ArgentinaFil: del Mauro, Julieta SofĂa. Universidad de Buenos Aires. Facultad de Farmacia y BioquĂmica. Departamento de FarmacologĂa; ArgentinaFil: Lovera, Valeria. Universidad de Buenos Aires. Facultad de Farmacia y BioquĂmica. Departamento de FarmacologĂa; ArgentinaFil: Chiappetta, Diego AndrĂ©s. Universidad de Buenos Aires. Facultad de Farmacia y BioquĂmica. Departamento de TecnologĂa FarmacĂ©utica; Argentina. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas; ArgentinaFil: Polizio, Ariel HĂ©ctor. Universidad de Buenos Aires. Facultad de Farmacia y BioquĂmica. Departamento de FarmacologĂa; Argentina. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas; ArgentinaFil: Taira, Carlos Alberto. Universidad de Buenos Aires. Facultad de Farmacia y BioquĂmica. Departamento de FarmacologĂa; Argentina. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas; ArgentinaFil: Höcht, Christian. Universidad de Buenos Aires. Facultad de Farmacia y BioquĂmica. Departamento de FarmacologĂa; Argentin