Verkenning sensorgestuurde dosering van loofdodingsmiddelen in pootaardappelen

In 2008 is een verkenning gedaan naar haalbaarheid van sensorgestuurde dosering van loofdodingsmiddelen in pootgoedteelt van aardappelen. Er werd een prototype gebouwd en getest waarmee Finale pleksgewijs gedoseerd werd d.m.v. Greenseeker-sensoren op een klap-spuit-combinatie en een rekenregel die plaatspecifieke meetwaarden doorvertaalde in een minimum effectieve dosering. Ook werden dosis-response proeven uitgevoerd. De eerste resultaten met het prototype en systeem waren positief. Met de sensoren konden variatie in gewasstand in kaart gebracht worden, en deze bleek groter dan verwacht. Bovendien kon de dosering effectief gestuurd worden met de sensormeetwaarden. Het onderzoek laat zien dat reductie in loofdodingsmiddel met sensorsturing mogelijk is. In het onderzoek bleken ras en dosering van Finale geen effect te hebben op verkleuring van navels van knollen. Nader onderzoek aan de beslisregels, validatie in de praktijk inclusief effecten op kwaliteit van de aardappelen is nodig voor implementatie in de praktij

Risk factors for non-closure of an intended temporary defunctioning stoma after emergency resection of left-sided obstructive colon cancer

Purpose: A substantial part (21–35%) of defunctioning stomas created during resection for colorectal cancer will never be reversed. Known risk factors for non-closure are age, peri- or postoperative complications, comorbidity, and tumor stage. However, studies performed to identify these risk factors mostly focus on rectal cancer and include both preoperative and postoperative factors. This study aims to identify preoperative risk factors for non-reversal of intended temporary stomas created during acute resection of left-sided obstructive colon cancer (LSOCC) with primary anastomosis. Methods: All patients who underwent emergency resection for LSOCC with primary anastomosis and a defunctioning stoma between 2009 and 2016 were selected from the Dutch ColoRectal Audit, and additional data were collected in the local centers. Multivariable analysis was performed to identify independent preoperative factors for non-closure of the stoma. Results: A total of 155 patients underwent acute resection for LSOCC with primary anastomosis and a defunctioning stoma. Of these, 51 patients (32.9%) did not have their stoma reversed after a median of 53 (range 7–104) months of follow-up. In multivariable analysis, hemoglobin &lt; 7.5 mmol/L (odds ratio (OR) 4.79, 95% confidence interval (95% CI) 1.60–14.38, p = 0.005), estimated glomerular filtration rate (eGFR) ≤ 45 mL/min/1.73 m2 (OR 4.64, 95% CI 1.41–15.10, p = 0.011), and metastatic disease (OR 6.12, 95% CI 2.35–15.94, p &lt; 0.001) revealed to be independent predictors of non-closure. Conclusions: Anemia, impaired renal function, and metastatic disease at presentation were found to be independent predictors for non-reversal of intended temporary stomas in patients who underwent acute resection for LSOCC. In patients who have an increased risk of non-reversal, the surgeon should consider a Hartmann’s procedure.</p

Unraveling the Formation of Gelatin Nanospheres by Means of Desolvation

Gelatin nanoparticles (GNPs) have been widely studied for a plethora of biomedical applications, but their formation mechanism remains poorly understood, which precludes precise control over their physicochemical properties. This leads to timeconsuming parameter adjustments without a fundamental grasp of the underlying mechanism. Here, we analyze and visualize in a timeresolved manner the mechanism by which GNPs are formed during desolvation of gelatin as a function of gelatin molecular weight and type of desolvating agent. Through various analytical and imaging techniques, we unveil a multistage process that is initiated by the formation of primary particles that are ∼18 nm in diameter (wet state). These primary particles subsequently assemble into colloidally stable GNPs with a raspberry-like structure and a hydrodynamic diameter of ∼300 nm. Our results create a basic understanding of the formation mechanism of gelatin nanoparticles, which opens new opportunities for precisely tuning their physicochemical and biofunctional properties.Radboud University Medical Cente

The lipopolysaccharide model for the experimental induction of transient lameness and synovitis in Standardbred horses

An established lipopolysaccharide (LPS) model previously described in Warmbloods, was inconsistent in Standardbred horses, where lameness was not detected despite the presence of synovitis. The present study aimed to determine the dose of LPS from E. coli O55:B5 required to induce mild to moderate lameness following middle carpal joint injection in Standardbred horses and to quantitate the induced lameness over time, with and without anti-inflammatory pre-treatment. In a baseline trial, eight healthy, clinically sound Standardbred horses were used in a rule-based dose-escalation design trial, starting at a dose of 10 endotoxin units (EU). Lameness at trot was evaluated visually and quantitatively (using an inertial-sensor system and pressure plate analysis). Synovial fluid aspirates were analysed for total nucleated cell counts, total protein and prostaglandin E2 (PGE2). Following 2 months wash-out, the effective LPS-dose determined in the baseline trial was used to evaluate the effect of anti-inflammatory treatment. A mixed model for repeated measures with horse as random effect was used for analysis. After injection of 10 EU LPS, the desired degree of lameness was observed in the baseline trial, with maximal lameness at post-injection hour (PIH) 4, followed by a rapid decline and return to baseline by PIH 48. No lameness was observed following pre-treatment with meloxicam. In synovial fluid, PGE2 was significantly higher at PIH 8 and PIH 24 in the baseline trial compared with following meloxicam pre-treatment. In conclusion, injection of the middle carpal joint with 10 EU LPS consistently induces a transient lameness and synovitis in Standardbred horses