Follow-up of tumor development in the colons of living rats and implications for chemoprevention trials: assessment of aspirin-difluoromethylornithine combination.

We aimed to establish a reliable procedure allowing the follow-up of tumor development by computed tomographic (CT) colonography in an animal model of colon carcinogenesis in order to assess the chemopreventive efficacy of aspirin and difluoromethylornithine (DFMO) given in combination. Fischer rats received an intraperitoneal injection (25 mg/kg) of dimethylhydrazine (DMH) once a week for two weeks in order to initiate colon carcinogenesis. Five months after the last injection of DMH, a first CT colonography was performed and rats were then randomly separated into two groups (control and experimental).

Trajectory optimization for the planning of percutaneous radiofrequency ablation of hepatic tumors.

Radiofrequency ablation is increasingly used in the treatment of hepatic tumors. Planning the percutaneous intervention is essential and particularly difficult. In this paper, we focus on an automated computation of optimal needle insertion in computer-assisted surgery with 3D visualization.

Precise determination of regions of interest for hepatic RFA planning.

Percutaneous radiofrequency ablation is a minimally invasive therapy for the treatment of liver tumors that consists in a destruction of tumors by heat. A correct insertion and placement of the needle inside the tumor is critical and conditions the success of the operation. We are developing a software that uses patients data to help the physician plan the operation.

Design of robust vascular tree matching: validation on liver.

In this paper, we propose an original and efficient tree matching algorithm for intra-patient hepatic vascular system registration. Vascular systems are segmented from CT-scan images acquired at different times, and then modeled as trees. The goal of this algorithm is to find common bifurcations (nodes) and vessels (edges) in both trees.

A modular and evolutive component oriented software architecture for patient modeling.

This paper deals with the design aspect of a software aiming at modeling the anatomical and pathological structures of patients from medical images, for diagnosis purposes. In terms of functionalities, it allows to combine image processing algorithms, and to visualize and manipulate 3D models and images. The proposed software uses specific extensible and reusable components and a system managing their combination, thanks to a formal XML-based description of their interfaces.

An interactive medical image segmentation system based on the optimal management of regions of interest using topological medical knowledge.

This paper presents an original interactive system for efficient medical image segmentation in computer aided diagnosis. The main originality concerns the method used to manage, according to an a priori topological-based structural model, regions of interest (ROIs) within which computations can be constrained. The goal is then to avoid the processing of irrelevant image points, therefore improving and accelerating segmentations.

Liver registration for the follow-up of hepatic tumors.

In this paper we propose a new two step method to register the liver from two acquisitions. This registration helps experts to make an intra-patient follow-up for hepatic tumors. Firstly, an original and efficient tree matching is applied on different segmentations of the vascular system of a single patient.

Optimal trajectories computation within regions of interest for hepatic RFA planning.

Percutaneous radiofrequency ablation has become a frequently used technique for the treatment of liver cancers, but still remains very difficult to plan. In this paper, we propose a robust method to delineate on the skin of a 3D reconstructed patient the zones that are candidate for an insertion, because they allow a safe access to the tumor without meeting any organ, and to compute automatically within these zones an optimal trajectory minimizing the volume of necrosis covering the tumor.

A complete augmented reality guidance system for liver punctures: first clinical evaluation.

We provided in an augmented reality guidance system for liver punctures, which has been validated on a static abdominal phantom. In this paper, we report the first in vivo experiments. We developed a strictly passive protocol to directly evaluate our system on patients.

Phenotypic, genotypic, and phylogenetic discrepancies to differentiate Aeromonas salmonicida from Aeromonas bestiarum.

The taxonomy of the "Aeromonas hydrophila" complex (comprising the species A. hydrophila, A. bestiarum, A.

Radiofrequency ablation of hepatic tumors: simulation, planning, and contribution of virtual reality and haptics.

For radiofrequency ablation (RFA) of liver tumors, evaluation of vascular architecture, post-RFA necrosis prediction, and the choice of a suitable needle placement strategy using conventional radiological techniques remain difficult. In an attempt to enhance the safety of RFA, a 3D simulator, treatment planning, and training tool, that simulates the insertion of the needle, the necrosis of the treated area, and proposes an optimal needle placement, has been developed. The 3D scenes are automatically reconstructed from enhanced spiral CT scans.

Trematodes associated with mangrove habitat in Puerto Rican salt marshes.

Batillaria minima is a common snail in the coastal estuaries of Puerto Rico. This snail is host to a variety of trematodes, the most common being Cercaria caribbea XXXI, a microphallid species that uses crabs as second intermediate hosts. The prevalence of infection was higher (7.

Real-time ultrasonography simulator based on 3D CT-scan images.

A new method for real-time simulation of ultrasonography is presented. This method uses directly 3D enhanced helical CT-scan images. The originality of this method is that it can be run directly on real patient data with no need of any pretreatment.

First record of the rare species Aeromonas culicicola from a drinking water supply.

We describe the recovery of the rare species Aeromonas culicicola, so far known only in mosquitoes in India, from a drinking water supply in Spain. Typing, using enterobacterial repetitive intergenic consensus-PCR, revealed that the 27 new isolates belonged to 3 very closely related strains. These strains were genetically identified by 16S rRNA gene sequencing.

Argonaute 3D: a real-time cooperative medical planning software on DSL network.

Today, diagnosis of cancer and also therapeutic choice imply many specialized practitioners. They are generally located at different places and have to take the best decision as promptly as possible with the difficulty of CT-scan or MRI interpretation. Argonaute 3D is a tool that easily overcomes these issues, thanks to a cooperative solution based on virtual reality.

Complete type III secretion system of a mesophilic Aeromonas hydrophila strain.

We have investigated the existence and genetic organization of a functional type III secretion system (TTSS) in a mesophilic Aeromonas strain by initially using the Aeromonas hydrophila strain AH-3. We report for the first time the complete TTSS DNA sequence of an Aeromonas strain that comprises 35 genes organized in a similar disposition as that in Pseudomonas aeruginosa. Using several gene probes, we also determined the presence of a TTSS in clinical or environmental strains of different Aeromonas species: A.

Phylogenetic analysis of the genus Aeromonas based on two housekeeping genes.

The phylogenetic relationships of all known species of the genus Aeromonas, and especially Aeromonas bestiarum and Aeromonas salmonicida, were investigated on 70 strains using the rpoD sequence, which encodes the sigma70 factor. This analysis was complemented with the sequence of gyrB, which has already proven useful for determining the phylogenetic relationships in the genus. Nucleotide sequences of rpoD and gyrB showed that both genes had similar substitution rates (< 2 %) and a similar number of variable positions (34 % for rpoD versus 32 % for gyrB).

Three-dimensional virtual cholangioscopy: a reliable tool for the diagnosis of common bile duct stones.

Objective: Our goal was to evaluate the clinical reliability of a new software system employing 3-dimensional (3D) virtual anatomic reconstruction and intraluminal virtual exploration for detection of choledocholithiasis and preoperative visualization of the biliary anatomy.

Summary Background Data: Virtual reality systems have been proposed for gastroscopy, bronchoscopy, and colonoscopy, as well as for the 3D reconstruction of liver anatomy and hepatic lesions. The impact of these systems in preoperative diagnostics has not been established due to the lack of large clinical series evaluating their reliability.

Type III secretion system genes in clinical Aeromonas isolates.

We have identified the genes ascF and ascG, which encode components of a putative type III secretion system (TTSS) in AEROMONAS: We investigated the distribution of these and other TTSS genes in 84 clinical isolates and found hybridizing sequences in 50% of the strains, with a higher prevalence in Aeromonas hydrophila and Aeromonas veronii than in Aeromonas caviae.

Evaluation of two miniaturized systems, MicroScan W/A and BBL Crystal E/NF, for identification of clinical isolates of Aeromonas spp.

Fifty-two clinical strains and 22 type and reference Aeromonas strains, previously genetically characterized by 16S rRNA gene restriction fragment length polymorphism, were identified in parallel with the MicroScan Walk/Away and BBL Crystal Enteric/Nonfermenter systems. The former identified only 14.8% of the isolates correctly, and the latter identified only 20.

Distribution of virulence genes in clinical and environmental isolates of Aeromonas spp.

The distribution and phenotypic activity of the genes encoding for serine protease, glycerophospholipid-cholesterol acyltransferase, lipases, aerolysin/hemolysin and DNases were investigated in 234 isolates identified by 16S rDNA-RFLP representing all the species of Aeromonas. The former three genes were found to be highly conserved among the genus. Aerolysin/hemolysin and DNase genes and beta-hemolytic activity were significantly more frequent in clinical than in environmental isolates.

Intrapocket anesthesia for scaling and root planing in pain-sensitive patients.

Background: In 2 previous multicenter studies evaluating the efficacy of a novel anesthetic gel (lidocaine 25 mg/g plus prilocaine 25 mg/g), there was a rather small, although statistically significant, overall difference between the active and placebo gels. There were, however, large center variations. At centers where the placebo-treated patients reported high pain scores, the difference between treatments was large, suggesting that the anesthetic gel is most effective in patients who experience the procedure as painful.