Radiofrequency ablation of liver tumors: technique and preliminary results

Radiofrequency ablation is a therapeutic method more and more applied for unresectable liver tumors; the purpose of this study is to evaluate its advantages and disadvantages. A series of 14 cases with liver tumors was treated by radiofrequency ablation; in 5 cases (35.7%) a hepatic resection was associated. Laboratory data, complications, morbidity, mortality and survival were noted. Mean age was 57.4 years (40-70) for this series consisting of 8 women and 6 men. The mean number of tumors treated per patient was 2.2; the mean total tumoral diameter was 7.2 cm. There were no major technique related complications, nor perioperative mortality. Mean global survival was 507.4 days; one year mean global survival was 64.2% (9 cases) and two years mean global survival was 28.5% (4 cases). We presented the technique of radiofrequency ablation applied for liver tumors and our experience because it is less known and used in our country and there is a tendency to treat liver tumors by this mean.     

Nonrigid registration method to assess reproducibility of breath-holding with ABC in lung cancer

PURPOSE: To study the interfraction reproducibility of breath-holding using active breath control (ABC), and to develop computerized tools to evaluate three-dimensional (3D) intrathoracic motion in each patient. METHODS AND MATERIALS: Since June 2002, 11 patients with non-small-cell lung cancer enrolled in a Phase II trial have undergone four CT scans: one during free-breathing (reference) and three using ABC. Patients left the room between breath-hold scans. The patient's breath was held at the same predefined phase of the breathing cycle (about 70% of the vital capacity) using the ABC device, then patients received 3D-conformal radiotherapy. Automated computerized tools for breath-hold CT scans were developed to analyze lung and tumor interfraction residual motions with 3D nonrigid registration. RESULTS: All patients but one were safely treated with ABC for 7 weeks. For 6 patients, the lung volume differences were <5%. The mean 3D displacement inside the lungs was between 2.3 mm (SD 1.4) and 4 mm (SD 3.3), and the gross tumor volume residual motion was 0.9 mm (SD 0.4) to 5.9 mm (SD 0.7). The residual motion was slightly greater in the inferior part of the lung than the superior. For 2 patients, we detected volume changes >300 cm(3) and displacements >10 mm, probably owing to atelectasia and emphysema. One patient was excluded, and two others had incomplete data sets. CONCLUSION: Breath-holding with ABC was effective in 6 patients, and discrepancies were clinically accountable in 2. The proposed 3D nonrigid registration method allows for personalized evaluation of breath-holding reproducibility with ABC. It will be used to adapt the patient-specific internal margins.     

Enhanced (hydrodynamic) transport induced by population growth in reaction-diffusion systems with application to population genetics

We consider a system made up of different physical, chemical, or biological species undergoing replication, transformation, and disappearance processes, as well as slow diffusive motion. We show that for systems with net growth the balance between kinetics and the diffusion process may lead to fast, enhanced hydrodynamic transport. Solitary waves in the system, if they exist, stabilize the enhanced transport, leading to constant transport speeds. We apply our theory to the problem of determining the original mutation position from the current geographic distribution of a given mutation. We show that our theory is in good agreement with a simulation study of the mutation problem presented in the literature. It is possible to evaluate migratory trajectories from measured data related to the current distribution of mutations in human populations.     

Why human pemphigoid autoantibodies do not trigger disease by the passive transfer into mice?

The recapitulation of disease features in animals by the transfer of patient autoantibodies has been used to demonstrate the autoimmune nature of several diseases. Failure of disease induction by the passive transfer of autoantibodies has been assigned to a limited cross-reactivity of the autoantibodies with the murine tissue. However, the possibility that the passively transferred "inflammatory" patient autoantibodies may not be able to unfold their pathogenic potential due to restricted Fc-dependent effector functions has not yet been systematically explored. In this study we analyze the interaction of patients' autoantibodies with murine complement and granulocytes. Bullous pemphigoid is a blistering disease associated with autoantibodies, which are thought to induce subepidermal blistering by activating complement and granulocytes. The passive transfer of patients autoantibodies failed to induce skin blistering in wild type mice. The cross-reactivity of pemphigoid autoantibodies with murine antigens was analyzed in silico, ex vivo and by the passive transfer of IgG in vivo. Complement-fixing ability of patients' autoantibodies was evaluated by complement-binding test. Granulocyte activation was assessed by reactive oxygen species production assay and the cryosection model. We have found that although pemphigoid autoantibodies bound to murine skin in vitro and in vivo, they showed a lower capacity to fix murine complement and a reduced ability to activate murine granulocytes when compared with human complement and cells, respectively. These results indicate that for disease models using the passive transfer of patient autoantibodies, their interaction with the innate factors of the host should be optimized to match the human situation.     

Nutrition and physical activity in NAFLD: an overview of the epidemiological evidence

Nonalcoholic fatty liver disease(NAFLD)has been recognized as a major health burden.The high prevalence of NAFLD is probably due to the contemporary epidemics of obesity,unhealthy dietary pattern,and sedentary lifestyle.The efficacy and safety profile of pharmacotherapy in the treatment of NAFLD remains uncertain and obesity is strongly associated with hepatic steatosis;therefore,the first line of treatment is lifestyle modification.The usual management of NAFLD includes gradual weight reduction and increas...     

Unique case of primary malignant fibrous histiocytoma of the right ventricle with moderator band involvement

Malignant primary tumors of the heart are very rare and in most cases are located in the left side of the heart, but involvement of the moderator band of the right heart has not yet been described in the literature. We report the case of a 22-year-old woman who presented after an episode of transient sudden loss of consciousness. The transthoracic echocardiography (TTE) and transesophageal echocardiography evaluations showed an echogenic mass that originated in the right ventricle and protruded into the tricuspid valve during systole. While operating on the patient, we found a sessile tumor that originated exclusively from the moderator band of the right ventricle. The tumor was completely resected through the tricuspid valve. An immunohistochemistry examination of the tumor confirmed the diagnosis of a malignant fibrous histiocytoma (MFH) (undifferentiated pleomorphic sarcoma). To our knowledge, this case is the first of moderator band involvement among the 50 cases of primary MFH of the heart that have been reported in the literature. After a year and a half, TTE, computed tomography (CT), and positron emission tomography CT (PET-CT) showed the absence of cardiac tumor, a normal tricuspid function, and no metastasis. The completeness of the surgical resection and the absence of local recurrence >1 year after surgery are encouraging signs for the patient's outcome.     

The advantages of implementing an e-learning platform for laparoscopic liver surgery

The rapid expansion of laparoscopic surgery has led to the development of training methods for acquiring technical skills. The importance and complexity of laparoscopic liver surgery are arguments for developing a new integrated system of teaching, learning and evaluation, based on modern educational principles, on flexibility allowing wide accessibility among surgeons. This paper presents the development of e-learning platform designed for training in laparoscopic liver surgery and pre-planning of the operation in a virtual environment. E-learning platform makes it possible to simulate laparoscopic liver surgery remotely via internet connection. The addressability of this e-learning platform is large, being represented by young surgeons who are mainly preoccupied by laparoscopic liver surgery, as well as experienced surgeons interested in obtaining a competence in the hepatic minimally invasive surgery.     

Anti-CD25 treatment and FOXP3-positive regulatory T cells in heart transplantation

The interleukin-2 receptor alpha chain (IL-2Ra, CD25) plays a major part in shaping the dynamics of T cell populations following immune activation, due to its role in T cell proliferation and survival. Strategies to blunt the effector responses in transplantation have been developed by devising pharmaceutical agents to block the IL-2 pathways. However, such strategies could adversely affect the CD25(+)FOXP3(+)T regulatory (T reg) populations which also rely on intereukin-2 signaling for survival. The present study shows that a cohort of heart allograft recipients treated with Daclizumab (a humanized anti-CD25 antibody) display FOXP3 expression patterns consistent with functional T regulatory cell populations. High levels of FOXP3 were observed to correlate with lower incidence of and recovery from acute rejection, as well as lower levels of anti-donor HLA antibody production. Therefore, T reg populations appear fully functional in patients treated with Daclizumab, even when 5 doses were administered. By comparison, patients treated with fewer doses or no Daclizumab had a higher incidence of acute rejection, antibody production and graft failure. Therefore, our data indicates that Daclizumab treatment does not interfere with the generation of regulatory T cells and has a beneficial effect on heart allograft survival.