Development of pH-responsive Eudragit S100-functionalized silk fibroin nanoparticles as a prospective drug delivery system.

Silk fibroin nanoparticles (FNP) have been increasingly investigated in biomedical fields due to their biocompatibility and biodegradability properties. To widen the FNP versatility and applications, and to control the drug release from the FNP, this study developed the Eudragit S100-functionalized FNP (ES100-FNP) as a pH-responsive drug delivery system, by two distinct methods of co-condensation and adsorption, employing the zwitterionic furosemide as a model drug. The particles were characterized by sizes and zeta potentials (DLS method), morphology (electron microscopy), drug entrapment efficiency and release profiles (UV-Vis spectroscopy), and chemical structures (FT-IR, XRD, and DSC). The ES100-FNP possessed nano-sizes of ∼200-350 nm, zeta potentials of ∼ -20 mV, silk-II structures, enhanced thermo-stability, non-cytotoxic to the erythrocytes, and drug entrapment efficiencies of 30%-60%, dependent on the formulation processes. Interestingly, the co-condensation method yielded the smooth spherical particles, whereas the adsorption method resulted in durian-shaped ones due to furosemide re-crystallization. The ES100-FNP adsorbed furosemide via physical adsorption, followed Langmuir model and pseudo-second-order kinetics. In the simulated oral condition, the particles could protect the drug in the stomach (pH 1.2), and gradually released the drug in the intestine (pH 6.8). Remarkably, in different pH conditions of 6.8, 9.5, and 12, the ES100-FNP could control the furosemide release rates depending on the formulation methods. The ES100-FNP made by the co-condensation method was mainly controlled by the swelling and corrosion process of ES100, and followed the Korsmeyer-Peppas non-Fickian transport mechanism. Whereas, the ES100-FNP made by the adsorption method showed constant release rates, followed the zero-order kinetics, due to the gradual furosemide dissolution in the media. Conclusively, the ES100-FNP demonstrated high versatility as a pH-responsive drug delivery system for biomedical applications.

Effects of Feed Mixed with Lactic Acid Bacteria and Carbon, Nitrogen, Phosphorus Supplied to the Water on the Growth and Survival Rate of White Leg Shrimp (Penaeus vannamei) Infected with Acute Hepatopancreatic Necrosis Disease Caused by Vibrio parahaemolyticus.

This study aimed to evaluate the growth, survival rate, and resistance to acute hepatopancreatic necrosis disease (AHPND) of white leg shrimp (Penaeus vannamei) by using Lactobacillus plantarum, Lactobacillus fermentum, and Pediococcus pentosaceus mixed with feed, and at the same time supplying CNP in a ratio of 15:1:0.1 to the water. As a result, the treatments that shrimp were fed with feed containing lactic acid bacteria (LAB), especially L. plantarum, have increased shrimp growth, total hemocyte cells, granulocyte cells, and hyaline cells significantly (p < 0.05) in comparison to the control group. The supply of CNP to the water has promoted the intensity of V. parahaemolyticus effects on shrimp health and significantly decreased total hemocyte cells, granulocyte cells, and hyaline cells by 30-50% in the period after three days of the challenge, except in L. plantarum treatment, which had only a 20% decrease compared to other treatments. In CNP supplying treatments, the AHPND infected rate and mortality of shrimp were higher than those in other treatments. In summary, the supply of CNP had significantly reduced the shrimp's immune response and promoted the susceptibility of shrimp to AHPND in both cases of use with and without LAB-containing diets.

Transpelvic anastomotic stenting: a good option for diversion after pyeloplasty in children.

PURPOSE: Several options are available to drain the renal pelvis after a dysmembered pyeloplasty. The purpose of our study was to review the results of transrenal pelvic transanastomotic stenting following ureteropelvic junction obstruction pyeloplasty (UPJO). PATIENTS AND METHODS: A retrospective chart review of 238 patients with UPJO (243 renal units) treated in 2004-2007. The patients were divided into 4 groups (1): renal units with very poor function (<10% uptake) having undergone nephrostomy tube placement, with pyeloplasty performed 1 month later for those with improved renal function, and nephrectomy for those with no improvement (2); pyeloplasty without diversion (3); pyeloplasty diverted with transrenal pelvis transanastomotic stenting (4); pyeloplasties diverted with both stents and Foley catheters; the stents used were 5 Fr or 6 Fr feeding tubes. RESULTS: Group 1: 13 nephrectomies and 31 pyeloplasties diverted with stents and Foley catheters; 1/31 re-do pyeloplasty. Group 2: 33 pyeloplasties that were performed without diversion or stenting; 2/33 required re-do pyeloplasty. Group 3: 122 pyeloplasties diverted with only stents inserted through renal pelvis with 1 nephrostomy due to urine leakage, 2 prolonged urine leaks that ceased spontaneously, 1 urinary infection, no re-do pyeloplasty needed. Group 4: 44 pyeloplasties that were performed with stents and nephrostomy tubes, 2 delays of removal of Foley catheters, no re-do pyeloplasty needed. CONCLUSIONS: Transrenal pelvis transanastomotic stenting using a feeding tube is a good option for diverting urine following dysmembered pyeloplasty in children.