Whole-heart 4D flow cardiac magnetic resonance in healthy dogs.

INTRODUCTION: In cardiac magnetic resonance imaging (CMR), accurate flow measurements rely on perpendicular plane-alignment with flow direction. For 2D phase contrast (PC) cardiac magnetic resonance measurements, planes have to be defined during the examination of the heart, which is time consuming and error-prone. Collection of flow information of the entire volume of the heart by a 4D flow CMR postpones plane alignment to post-processing. Sampling of such a large amount of data requires acceleration of data acquisition with techniques such as SENSitivity Encoding (k-t SENSE) or Broad-use Linear Acquisition Speed-up Technique (k-t BLAST). Objectives of the study were to compare 4D flow CMR, accelerated with two different acceleration methods with the established 2D PC CMR based on assessment of stroke volume at all four cardiac valves. The values of stroke volume acquired with the 4D flow CMR SENSE did not differ significantly when compared to the 2D PC CMR SENSE at the left side of the heart (aortic and mitral valve). Significant differences between the techniques were seen at the pulmonic and tricuspid valves. Acceleration with k-t BLAST revealed significantly lower values of stroke volume at all cardiac valves, except at the mitral valve.

INTRODUCTION: Lors d'examens cardiaques par résonnance magnétique (CMR), le plan pour des mesures de flux précises doit être défini perpendiculairement à la direction de flux sanguin. Dans la CMR en contraste de phases 2D (PC), le choix de ce plan se fait durant l'examen, ce qui prend du temps et peut être sujet à des problèmes. Avec la mesure de toutes les données relatives au flux sanguin dans l'ensemble du coeur au moyen d'un 4D flow CMR, on déplace le moment de ce choix dans la phase de traitement des données. La collecte d'une quantité aussi élevée de données nécessite une accélération de la technique de mesures comme par exemple SENSitivity Encoding (k-t SENSE) ou Broad-use Linear Acquisition Speed-up Technique (k-t BLAST). Le but de cette étude était de comparer la CMR 4D, accélérée avec deux méthodes différentes avec la CMR 2D bien établie, ceci sur la base de la détermination du volume d'éjection systolique au niveau des quatre valvules cardiaques. Les valeurs du volume d'éjection pour le coeur gauche (valvules aortiques et mitrales) obtenues par 4D flow CMR k-t SENSE n'étaient pas significativement différentes de celles obtenues par 2D PC CMR k-t SENSE. Par contre, des différences significatives entre les deux techniques étaient constatées au niveau des valvules pulmonaires et tricuspid. L'accélération par k-t-BLAST donnait de façon générale des valeurs du volume d'élection plus basses au niveau de toutes les valvules, à l'exception de la valvule mitrale.

The role of sentinel lymph node mapping in small animal veterinary medicine: A comparison with current approaches in human medicine.

The relevance of regional lymph node (LN) assessment to quantify the metastatic spread of cancer is well recognized in veterinary oncology. Evaluation of LNs is critical for tumour staging. However, sampling the correct LN may not be possible without sentinel lymph node (SLN) mapping. Methods for diagnostic imaging and intraoperative detection of SLNs are well established in human medicine, in particular, the combination of lymphoscintigraphy and intraoperative application of blue dyes. Nevertheless, alternative imaging techniques are available and have gained increasing interest. Successful implementation of these techniques in dogs have been reported in both clinical and experimental studies. This review aims to provide an overview of SLN mapping techniques in human and veterinary medicine.

Oesophageal and gastric endoscopic foreign body removal: complications and follow-up of 102 dogs.

OBJECTIVES: To assess complication rate, risk factors for complications and outcome in dogs with oesophageal and gastric endoscopic foreign body (FB) removal. METHODS: Medical records of 102 dogs undergoing endoscopic removal of oesophageal and/or gastric FBs from March 2001 to November 2006 were retrospectively reviewed. All owners were contacted by telephone to provide follow-up information. RESULTS: West Highland white terriers, Yorkshire terriers and Bernese mountain dogs were over-represented compared to the hospital population. Endoscopy alone was successful in 92/102 dogs (90.2 per cent), whereas gastrotomy (but no oesophagotomy) was required in 10 dogs (9.8 per cent). Complications in 13/102 dogs (12.7 per cent) were perforation (8), oesophageal stricture (1), oesophageal diverticula (1), perioesophageal abscess (1), pneumothorax and pleural effusion (1) and respiratory arrest (1). Six dogs (all weighing <10 kg) had complications resulting in death or euthanasia. Bone FBs, bodyweight of less than 10 kg, and oesophageal or gastric FB in place for more than three days were significant risk factors for complications. Of the dogs available for follow-up (75/96), 92 per cent had no complications after discharge. CLINICAL SIGNIFICANCE: Endoscopic FB removal is associated with a low overall complication rate with bone FBs and bodyweight of less than 10 kg as significant risk factors.

Solubilization and growth of Candida pseudotropicalis in water-in-oil microemulsions.

Some new aspects of microbiology in water-in-oil microemulsions are investigated using Candida pseudotropicalis in a hexadecane solution containing Tween85/Span80 (each 5% wt:wt) as surfactant, and limited amount of water (up to 3%, vol:vol), Microemulsion solutions containing cells up to 10 mg fresh weight per milliliter can be prepared, which display a greater time stability and a much smaller light scattering than aqueous suspensions having the same cell concentration. This is ascribed to a lower aggregation tendency of the cells in the microemulsion environment. It is also shown that C. pseudotropicalis cells are able to grow (up to a factor of approximately 6-7 within a few days) in the microemulsion system containing nutrient medium in the aqueous microphase; but they are also able to grow at the expense of the hexadecane. This is proved with radioactive-labeled hexadecane by measuring the increase of radioactivity in the cells as well as the emission of (14)CO(2). The growth rate of the cells is then compared with the growth rate of cellular proteins during cell reproduction in the microemulsion system. Two regimes are observed: a first one, in which cells growth rate and protein growth rate proceed parallel to each other; and a second one (established after 0.5-1 day) characterized by depletion of proteins in the microemulsion system. The implications of these findings for cell metabolism in microemulsion and for possible biotechnological applications are discussed.

Solubilization and activity of yeast cells in water-in-oil microemulsion.

Baker yeast cells are solubilized in organic solvents by the use of surfactants and small amounts of water. Data are reported for three different systems, Tween/Isopropylpalmitat, Asolectin/IPP, Asolectin/Hexadecane. The viability (life-capability) can remain as high as 80% for 10 Days, the asolectin systems being more efficient. The viability is significantly higher for yeast cells derived from cultures which had been previously solubilized in the microemulsion system. The implications of the finding for microbiology in organic solvents, and some general mechanistic aspects, are briefly discussed.