Outcomes of a prospective multi-center trial of a second-generation composite mesh for open ventral hernia repair.

PURPOSE: Composite mesh prostheses incorporate properties of multiple materials for use in open ventral hernia repair (OVHR). This study examines clinical outcomes in patients who underwent OVHR with a polypropylene/expanded polytetrafluoroethylene (ePTFE) composite graft containing a novel polydioxanone (PDO) absorbable ring to facilitate placement and graft positioning. METHODS: Data were prospectively collected on consecutive patients undergoing OVHR using a synthetic composite mesh. Seven centers enrolled patients during the study period. All patients underwent a standardized surgical procedure consisting of OVHR with sublay intraperitoneal placement of mesh. Mesh fixation was accomplished with peripheral tacks and transfascial sutures. RESULTS: One hundred and nineteen patients underwent OVHR with the composite mesh. Average age was 55.8 years; there were 71 (59.7 %) females and 48 (40.3 %) males with mean BMI of 33.5 ± 7.1 kg/m(2). One hundred and two (85.7 %) patients presented with primary ventral hernias. Mean defect size was 13.6 cm(2), and mean mesh size was 113.6 cm(2). Most patients (67 %) were discharged the day of surgery. Twelve patients (10.1 %) experienced complications in the perioperative time period primarily consisting of seroma (4.2 %) and ileus (1.7 %). Two patients required reoperation and mesh removal in the early postoperative period for infection and herniorrhaphy site pain, respectively. There was a decline in pain and movement limitation scores between baseline and 1-year follow-up. Six-month (n = 109) and twelve-month (n = 99) follow-up revealed no hernia recurrences (95 % CI 0-3 %, and 0-4 %, respectively). CONCLUSIONS: The use of this second-generation composite mesh was associated with no hernia recurrences and a low complication rate after open ventral hernia repair.

Inlay osmotic pump tablets containing metformin and glipizide.

The goal of diabetes therapy today is to achieve and maintain as near normal glycemia as possible to prevent the long-term microvascular and macrovascular complications of an elevated blood glucose. A newly developed inlay osmotic pump tablet (IOPT) can deliver glipizide (GLZ) and metformin HCl (MET) gradually in controlled manner. The aim of present investigation was to prepare the IOPT that can deliver >75% of GLZ in 2 h, whereas MET released after 2 h and sustained up to 12 h. In the present work, HP-ß-CD was used to modify the solubility of GLZ before incorporating in the osmotic system and MET was spray-dried with HPMC A15C to modify its release profile, flow property, and compressibility. Various parameters mainly G(75%) (75% GLZ release), t(LMET) (lag time of MET release from device), Q(10 h) (percent of MET released within 10 h), and RSQ(ZERO) (R(2) of release data fitted to zero-order equation) were used to compare different formulations. The effects of different formulation variables, that is, osmagents, concentration of hydrophilic polymer, diameter of drug releasing orifice, and coating composition on the drug release profile were investigated. The release rate of GLZ could be effectively modified by the addition of sodium carbonate and sodium chloride, whereas the release rate of MET was adjusted by dual-coating system and by addition of hydrophilic polymer. The developed inlay osmotic system could be effective in the multidrug therapy of diabetes by delivering both drugs in a controlled manner.

Evaluation of a new self-developing instant film for imaging and dosimetry.

Radiation sensitive films are standard dosimetric tools in radiation therapy. Films are used for machine quality assurance (QA) and treatment planning software evaluation. With the advent of intensity modulated radiation therapy (IMRT), simple and fast imaging technology is needed for patient-specific verification of radiation fields. Conventional radiographic films are often used. Radiochromic films, e.g. Gafchromic films, were recently introduced to the market. But these films have some disadvantages. JP Laboratories have developed a prototype radiochromic film, called SIFID (self-developing, instant film for imaging and dosimetry) with superior performance such that SIFID is unaffected by ambient light for months, stable up to 90 degrees C and can be archived. SIFID is made of polymerisable diacetylene. The film develops blue colour instantly upon absorbing radiation. We evaluated the film for radiation therapy applications. Our preliminary data demonstrate its feasibility as a dosimetric tool for IMRT QA as well as for other applications.

Modeling alternation to synchrony with inhibitory coupling: a neuromorphic VLSI approach.

We developed an analog very large-scale integrated system of two mutually inhibitory silicon neurons that display several different stable oscillations. For example, oscillations can be synchronous with weak inhibitory coupling and alternating with relatively strong inhibitory coupling. All oscillations observed experimentally were predicted by bifurcation analysis of a corresponding mathematical model. The synchronous oscillations do not require special synaptic properties and are apparently robust enough to survive the variability and constraints inherent in this physical system. In biological experiments with oscillatory neuronal networks, blockade of inhibitory synaptic coupling can sometimes lead to synchronous oscillations. An example of this phenomenon is the transition from alternating to synchronous bursting in the swimming central pattern generator of lamprey when synaptic inhibition is blocked by strychnine. Our results suggest a simple explanation for the observed oscillatory transitions in the lamprey central pattern generator network: that inhibitory connectivity alone is sufficient to produce the observed transition.