Comparison of macroscopic resorption time for a self-locking device and suture material in ovarian pedicle ligation in dogs.

A resorbable self-locking device (LigaTie) was developed to enable safe and easy surgical ligation of blood vessels. The aim of this study was to compare the long-term in vivo resorption of the device to a commercially available suture of equivalent material (Maxon) following ovarian pedicle ligation. After ovariohysterectomy follow-up ultrasound examinations were performed monthly on 21 dogs ligated with the device and 22 dogs ligated with the suture material until no hyperechoic remnants, acoustic shadowing or local tissue reactions were detected.

Resorbable Self-Locking Implant for Lung Lobectomy Through Video-Assisted Thoracoscopic Surgery: First Live Animal Application.

The aim of this pilot test was to test a new self-locking resorbable implant for hilum occlusion during a video-assisted thoracoscopic lung lobectomy in a surviving pig model. Once the thoracic cavity was assessed and structures identified, the right middle lobe and its respective hilum were exposed. The implant was introduced with a semiclosed loop through a working channel and positioned around the pulmonary lobe.

Ligation of the mesovarium in dogs with a self-locking implant of a resorbable polyglycolic based co-polymer: a study of feasibility and comparison to suture ligation.

Background: Ligation of the mesovarium in female dogs may be cumbersome with risk of complications and is associated with intense noxious stimuli. A resorbable implant, a self-locking loop designed for surgery, was developed as an alternative to traditional ligation. The study aimed to test the feasibility of ligating the canine ovarian pedicle with the implant and to compare its performance to traditional suture ligation.

Ligation of the spermatic cord in dogs with a self-locking device of a resorbable polyglycolic based co-polymer--feasibility and long-term follow-up study.

Background: New surgical techniques are developed to enable a quicker, easier and safer surgery with reduced risk of complications and shortened time needed for recovery. A resorbable device, a self-locking loop, was designed for surgical ligation. The objective of this pilot study was to investigate the feasibility of ligating the spermatic cord with the device, its biocompatibility and long-term resorption in dogs.

Modeling and robust pooling design of a preparative cation-exchange chromatography step for purification of monoclonal antibody monomer from aggregates.

This study has implemented and calibrated a model that describes the separation of the monomer of monoclonal antibodies from the dimer and larger oligomers on preparative-scale using cation-exchange chromatography. A general rate model with temperature dependent diffusion was coupled to a pH- and temperature-dependent steric mass action model. The model was shown to predict the retention of the monomer, dimer, and oligomer at low loadings for different pH levels and temperatures.

Experimental productivity rate optimization of rare earth element separation through preparative solid phase extraction chromatography.

Separating individual rare earth elements from a complex mixture with several elements is difficult and this is emphasized for the middle elements: Samarium, Europium and Gadolinium. In this study we have accomplished an overloaded one-step separation of these rare earth elements through preparative ion-exchange high-performance liquid chromatography with an bis (2-ethylhexyl) phosphoric acid impregnated column and nitric acid as eluent. An inductively coupled plasma mass spectrometry unit was used for post column element detection.

Kinetic modeling of lipase-catalyzed esterification reaction between oleic acid and trimethylolpropane: a simplified model for multi-substrate multi-product ping-pong mechanisms.

Kinetic models are among the tools that can be used for optimization of biocatalytic reactions as well as for facilitating process design and upscaling in order to improve productivity and economy of these processes. Mechanism pathways for multi-substrate multi-product enzyme-catalyzed reactions can become very complex and lead to kinetic models comprising several tens of terms. Hence the models comprise too many parameters, which are in general highly correlated and their estimations are often prone to huge errors.

Degradation profile and preliminary clinical testing of a resorbable device for ligation of blood vessels.

A resorbable device for ligation of blood vessels was developed and tested in vitro to reveal the degradation profile of the device and to predict the clinical performance in terms of adequate mechanical support during a healing period of 1week. In addition, preliminary clinical testing was performed that showed complete hemostasis and good tissue grip of renal arteries in five pigs. The device was made by injection molding of poly(glycolide-co-trimethylene carbonate) triblock copolymer, and it consisted of a case with a locking mechanism connected to a partly perforated flexible band.

Modelling and optimisation of preparative chromatographic purification of europium.

A model commonly used to describe the separation of biomolecules was used to simulate the harsh environment when eluting neodymium, samarium, europium and gadolinium with a hot acid. After calibration, the model was used to optimise the preparative separation of europium, as this is the most valuable of the four elements. A kinetic dispersive model with a Langmuir mobile phase modulator isotherm was used to describe the process.

Optimization of preparative chromatographic separation of multiple rare earth elements.

This work presents a method to optimize multi-product chromatographic systems with multiple objective functions. The system studied is a neodymium, samarium, europium, gadolinium mixture separated in an ion exchange chromatography step. A homogeneous Langmuir Mobile Phase Modified model is calibrated to fit the experiments, and then used to perform the optimization task.

A new resorbable device for ligation of blood vessels - A pilot study.

Background: During surgery, controlled haemostasis to prevent blood loss is vital for a successful outcome. It can be difficult to ligate vessels located deep in the abdomen. A device that is easy to use and enables secure ligatures could be beneficial.