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This study focused on the design of a thermoresponsive, nano-enabled vitreous substitute for the treatment of retinal diseases. Synthesis of a hydrogel composed of hyaluronic acid and a poloxamer blend was undertaken. Poly(D,L-lactide-co-glycolide) acid nanoparticles encapsulating triamcinolone acetonide (TA) were synthesised with a spherical morphology and mean diameter of ~ 153 nm. Hydrogel fabrication and nanoparticle loading within the hydrogel was confirmed via physicochemical analysis. Gelation studies indicated that hydrogels formed in nine minutes and 10 min for the unloaded and nanoparticle-loaded hydrogels, respectively. The hydrogels displayed in situ gel formation properties, and rheometric viscoelastic studies indicated the unloaded and loaded hydrogels to have modulus values similar to those of the natural vitreous at 37 °C. Administration of the hydrogels was possible via 26G needles allowing for clinical application and drug release of triamcinolone acetonide from the nanoparticle-loaded hydrogel, which provided sustained in vitro drug release over nine weeks. The hydrogels displayed minimal swelling, reaching equilibrium swelling within 12 h for the unloaded hydrogel, and eight hours for the nanoparticle-loaded hydrogel. Biodegradation in simulated vitreous humour with lysozyme showed < 20% degradation within nine weeks. Biocompatibility of both unloaded and loaded hydrogels was shown with mouse fibroblast and human retinal pigment epithelium cell lines. Lastly, a pilot in vivo study in a New Zealand White rabbit model displayed minimal toxicity with precise, localised drug release behaviour, and ocular TA levels maintained within the therapeutic window for the 28-day investigation period, which supports the potential applicability of the unloaded and nanoparticle-loaded hydrogels as vitreous substitutes that function as drug delivery systems following vitrectomy surgery., (© 2024. The Author(s).)

Objective: To assess the efficacy and safety of a covering method using polyglycolic acid (PGA) sheets and fibrin glue in preventing laryngopharyngeal bleeding after endoscopic laryngopharyngeal surgery (ELPS) combined with endoscopic submucosal dissection (ESD)., Methods: Twenty-one patients who underwent ELPS combined with ESD (28 resected pharyngeal carcinomas) were retrospectively evaluated. After completing ELPS combined with ESD, fibrinogen was sprayed onto the ulcer. A PGA sheet cut into 5 × 5 mm pieces that fit the size of the ELPS-induced ulcer was then placed over the ulcer and fixed in place with a fibrin glue comprising thrombin., Results: The resection procedure was performed for all lesions. The median long diameter of the resected specimen was 36 mm. The rate of a resected specimen diameter >30 mm, use of anticoagulant/platelet, and macroscopic classification 0-Ⅱa were 68% (19/28), 19% (5/28), and 36% (10/28), respectively. The median time required to cover ELPS-induced ulcers using PGA sheets and fibrin glue was 10 min (range: 3-22 min). No post-ELPS bleeding, subcutaneous emphysema, or aspiration pneumonia (0/28) was observed., Conclusion: The covering method using PGA sheets and fibrin glue for ELPS-induced ulcers is considered to be sufficiently safe and effective in preventing post-ELPS laryngopharyngeal bleeding. This method could be useful in preventing post-ELPS bleeding in patients with head and neck cancer., Competing Interests: Declaration of Competing Interest There are no conflicts of interest to declare., (Copyright © 2020. Published by Elsevier B.V.)

Background and Aims: Postoperative stricture after expansive esophageal endoscopic submucosal dissection (ESD) is a severe adverse event. Previous single-arm reports have suggested that polyglycolic acid (PGA) shielding may prevent stricture. This study was performed to assess the efficacy of this method through a comparative analysis., Methods: This is a retrospective analysis of 500 consecutive cases of esophageal ESD performed between 2002 and 2018 at the University of Tokyo Hospital. After 2013, patients with a diagnosis of superficial esophageal carcinoma covering more than half of the esophageal circumference underwent preventive treatment with either PGA shielding or steroid injection + PGA shielding after ESD. The efficacy of these methods for preventing post-ESD stricture was assessed through multivariable logistic regression analysis., Results: The risk of postoperative stricture was especially high in the cervical esophagus (odds ratio [OR], 4.60; 95% confidence interval [CI], 0.65-61.09) and after total circumferential resection (OR, 3.58×10 3 ; lower bound of 95% CI, >185). Steroid injection + PGA shielding was the only method significantly effective in preventing stricture (OR, 0.30; 95% CI, 0.10-0.78; P = .009). In the relatively low-risk subgroup (excluding cervical esophageal cancer and complete circumferential resection), the postoperative stricture rates for steroid injection + PGA shielding versus PGA shielding versus control were 18.9% versus 41.4% versus 51.7%, respectively (P = .015). However, the efficacy of this was limited in extremely high-risk cases., Conclusion: The combination of steroid injection and PGA shielding is effective for preventing post-ESD stricture. There is a need for even more effective methods for cervical esophageal cancer and complete circumferential resection., (Copyright © 2020 American Society for Gastrointestinal Endoscopy. Published by Elsevier Inc. All rights reserved.)

Albendazole is known as the drug of choice for medical treatment of cystic echinococcosis (CE). Albendazole sulfoxide (ABZ-SO), as the main active metabolite of albendazole, has low efficacy in the disease due to low water solubility and poor absorptivity. PLGA nanoparticles (NPs) enhance the dissolution of poorly soluble drugs, and chitosan (CS) coating enhances oral drug delivery of NPs. In this study, the efficacy of ABZ-SO-loaded CS-PGLA NPs in the treatment of CE was evaluated in laboratory mice. ABZ-SO-loaded CS-PGLA NPs were prepared by nanoprecipitation and characterized by dynamic light scattering method and scanning electron microscopy. Thirty mice were intraperitoneally infected by 1000 protoscoleces of Echinococcus granulosus. Ten months later, the mice were allocated into 3 groups: groups 1 and 2 were treated with ABZ-SO and ABZ-SO-loaded CS-PGLA NPs, respectively, and the mice in group 3 remained untreated as the control group. The drugs were administered by gavage for 45 days at a daily dose of 10 mg/kg. Finally, all mice were opened and the cysts were collected, counted, weighed, and measured separately. The therapeutic effect of ABZ-SO in the number, weight, and volume of the cysts were not statistically significant compared with those in ABZ-SO-loaded CS-PGLA NPs and the control group. However, the therapeutic effect of ABZ-SO-loaded CS-PGLA NPs in the weight and volume of cysts were statistically significant when compared with that in the control group (p ˂ 0.05). In conclusions, this study revealed that ABZ-SO-loaded CS-PGLA NPs could enhance the therapeutic efficacy of ABZ-SO in the treatment of CE in laboratory mice.

Objective: Endoscopic submucosal dissection (ESD) is the standard treatment for early gastric cancer (EGC). However, post-ESD bleeding remains a serious issue, particularly in patients treated with an antithrombotic agent or those have had a large mucosal resection (≥4 cm). Whether covering the ulcer bed induced by ESD with polyglycolic acid (PGA) sheets can prevent post-ESD bleeding remains to be questioned. Therefore, we performed a systematic review and meta-analysis to evaluate the effectiveness of PGA sheets on preventing post-ESD bleeding in patients with early gastric cancer (EGC) at a high risk of post-ESD bleeding., Methods: PubMed, Cochrane Library and EMBASE databases were searched for studies on the effect of PGA sheets shielding on inpatients with EGC and at a high risk of bleeding using post-ESD bleeding rate as the primary outcome., Results: Among the four included studies (212 lesions in the PGA sheet group and 208 in the control group), post-ESD bleeding rate was significantly lower in the PGA sheet group than in the control group (4.9% vs 13.7%, risk ratio [RR] 0.33, 95% confidence interval [CI] 0.18-0.72, P = 0.004). A subgroup analysis showed that the application of PGA sheets effectively reduced the post-ESD bleeding rate in patients receiving antithrombotic agents (5.5% vs 15.2%; RR 0.37, 95% CI 0.17-0.79, P = 0.01). Although the application of PGA sheets tended to decrease the post-ESD bleeding rate in patients who had undergone large mucosal resections, the difference was not significant (4.5% vs 9.6%; RR 0.52, 95% CI 0.15-1.78, P = 0.29)., Conclusions: PGA sheets can effectively prevent post-ESD bleeding in patients receiving antithrombotic agents. Further studies are needed to confirm whether PGA sheets can decrease post-ESD bleeding in patients underwent large mucosal resection., (© 2020 Chinese Medical Association Shanghai Branch, Chinese Society of Gastroenterology, Renji Hospital Affiliated to Shanghai Jiaotong University School of Medicine and John Wiley & Sons Australia, Ltd.)

Introduction: Many reports have indicated that adipose-derived stem cells (ADSCs) are effective for nerve regeneration. We investigated nerve regeneration by combining a polyglycolic acid collagen (PGA-c) tube, which is approved for clinical use, and Schwann cell-like differentiated ADSCs (dADSCs)., Methods: Fifteen-millimeter-long gaps in the sciatic nerve of rats were bridged in each group using tubes (group I), with tubes injected with dADSCs (group II), or by resected nerve (group III)., Results: Axonal outgrowth was greater in group II than in group I. Tibialis anterior muscle weight revealed recovery only in group III. Latency in nerve conduction studies was equivalent in group II and III, but action potential was lower in group II. Transplanted dADSCs maintained Schwann cell marker expression. ATF3 expression level in the dorsal root ganglia was equivalent in groups II and III., Discussion: dADSCs maintained their differentiated state in the tubes and are believed to have contributed to nerve regeneration., (© 2020 Wiley Periodicals, Inc.)

Objectives: A polyglycolic acid (PGA) patch is often used in pulmonary bullae resection, but consensus has not been reached on its effect on patient recovery. The aim of the study is to conduct a systematic review and meta-analysis of studies of polyglycolic acid for bullectomy., Methods: A comprehensive literature search was performed using ScienceDirect, EMBASE, Ovid MEDLINE, PubMed, The Cochrane Library, Scopus, and Google Scholar. Clinical trials that compared PGA versus non-PGA for bullectomy were selected. The clinical endpoints included postoperative recurrence, average postoperative air leakage, prolonged air leaks, drainage tube removal time, and postoperative hospital stay., Results: A total of eight articles (1095 patients) were included. Compared to the non-PGA approach, the PGA approach was associated with lower rates of postoperative recurrence (95% confidence interval [CI]: 0.16 to 0.39, p < 0.00001),) and of prolonged air leaks (95% CI: 0.29 to 0.72, p = 0.0007); a shorter time of drainage tube removal (95% CI: - 1.36 to - 0.13, p = 0.02); The time of average postoperative air leakage, postoperative hospital stay and operative time did not show a significant difference between the two groups., Conclusions: These results suggest that the use of PGA patch might can prevent the postoperative recurrence of spontaneous pneumothorax and decrease the rates of prolonged air leaks. More large-scale, high-quality randomized controlled trials are required to confirm our finding.

Inhaled antibiotic treatment of cystic fibrosis-related bacterial biofilm infections is challenging because of the pathological environment of the lungs. Here, we present an "environment-adaptive" nanoparticle composed of a solid poly lactic- co -glycolic acid (PLGA) core and a mucus-inert, enzymatically cleavable shell of d-α-tocopheryl polyethylene glycol 1000 succinate (TPGS) for the site-specific delivery of antibiotics to bacterial biofilms via aerosol administration. The hybrid nanoparticles with ultrasmall size were self-assembled via a nanoprecipitation process by using a facile microfluidic method. The interactions of the nanoparticles with the biological barriers were comprehensively investigated by using cutting-edge techniques (e.g., quartz crystal microbalance with dissipation monitoring, total internal reflection fluorescence microscopy-based particle tracking, in vitro biofilm model cultured in a flow-chamber system, and quantitative imaging analysis). Our results suggest that the mucus-inert, enzymatically cleavable TPGS shell enables the nanoparticles to penetrate through the mucus, accumulate in the deeper layer of the biofilms, and serve as sustained release depot, thereby improving the killing efficacy of azithromycin (a macrolide antibiotic) against biofilm-forming Pseudomonas aeruginosa . In conclusion, the ultrasmall TPGS-PLGA hybrid nanoparticles represent an efficient delivery system to overcome the multiple barriers and release antibiotics in a sustained manner in the vicinity of the biofilm-forming bacteria.

Whey-derived alpha-casozepine bioactive peptide (YLGYLEQLLR) was associated with previously optimized guar-gum film-PLGA nanoparticles, aiming to increase both stability across gastrointestinal tract and permeability across absorptive epithelia. Oral films associated with nanoparticles (FNp) enhance buccal absorption along with protection of carried bioactive molecules that are swallowed, with inherent increase of bioavailability. None of developed formulations induced significant loss of cell viability. Permeability across both buccal and intestinal cell barriers was enhanced when alpha-casozepine was carried by FNp system, when compared with film and nanoparticles alone, in a simulated gastrointestinal tract environment. Moreover, differences in permeability profile across buccal and intestinal epithelia were in accordance with the slower erosion of PLGA nanoparticles in a media of neutral pH, resembling oral cavity conditions, and a faster erosion in acidic conditions, as occurs in stomach, as observed by a continuous analysis of nanoparticle morphology over 980 min by atomic force microscopy. Additionally, apparent permeability of alpha-casozepine across TR146 human buccal carcinoma cells and Caco-2/HT29-MTX co-culture, carried by FNp was indeed superior when compared with peptide loaded in PLGA nanoparticles and in films alone or with free peptide control solution. Both FNp and PLGA nanoparticles alone enhanced the permeability of relaxing peptide compared with guar-gum films alone. An increased tongue adhesion when PLGA nanoparticles were added to the guar-gum films was also observed. Developed formulations improved both buccal an intestinal absorption of carried bioactive molecules without compromising cell viability., (Copyright © 2019. Published by Elsevier B.V.)

Purpose: Primary reconstruction via transconjunctival approach is a standardized treatment option for orbital floor fractures. The aim of this study was to compare the findings of specific ophthalmologic assessment with the patient's complaints after fracture reduction., Methods: A retrospective medical chart analysis was performed on patients who had undergone transconjunctival orbital floor fracture reduction for fracture therapy with resorbable foil (ethisorb sheet or polydioxanone foil). A follow-up assessment including ophthalmological evaluation regarding visual acuity (eye chart projector), binocular visual field screening (Bagolini striated glasses test) and diplopia (cover test, Hess screen test) was conducted. Additionally, a questionnaire was performed to assess patients' satisfaction., Results: A total of 53 patients with a mean follow-up of 23 months (ranging from 11 to 72) after surgical therapy were included. Diplopia was present preoperatively in 23 (43.4%) and reduced in follow-up examination (n = 12, 22.6%). Limitations in ocular motility reduced from 37.7% to 7.5%. The questionnaire about the patient's satisfaction revealed excellent outcomes in relation to the functional and esthetical parameters., Conclusion: Transconjunctival approach is a safe approach for orbital fracture therapy. Postoperative diplopia is nearly never perceptible for the individual and differs to pathologic findings in the ophthalmic assessment., (Copyright © 2019 Chinese Medical Association. Production and hosting by Elsevier B.V. All rights reserved.)

To improve the penetration and accumulation of anti-inflammatory drugs in colitis tissue, we functionalized the surface of porous poly(lactic-co-glycolic acid) nanoparticles (NPs) using pluronic F127 (PF127) and loaded curcumin (CUR) into the resulting NPs to obtain porous PF127-functionalized CUR-loaded NPs (porous PF127-NPs). These NPs had an average hydrodynamic diameter of about 270 nm with a highly monodisperse size distribution, slightly negative surface charge and controllable CUR release profile. It was found that they had good biocompatibility and yielded a much higher cellular uptake rate of CUR than porous CUR-loaded NPs without PF127 modification (porous NPs). In addition, porous PF127-NPs showed a greater capacity to inhibit the major pro-inflammatory cytokines (IL-6, IL-12 and TNF-α) secreted from lipopolysaccharide-activated macrophages than porous NPs and non-porous PF127-NPs. In vivo experiments suggested that porous PF127-NPs achieved the best therapeutic outcomes against ulcerative colitis (UC) in mice compared with porous NPs and non-porous PF127-NPs. Our results clearly demonstrate that these fabricated porous PF127-NPs show a great promise as an efficient CUR nanocarrier for UC therapy., (Copyright © 2018 Elsevier B.V. All rights reserved.)

A 74-year-old female, who was diagnosed with superficial esophageal cancer, underwent endoscopic submucosal dissection (ESD) at another hospital, but a perforation occurred during the procedure. The perforation was closed with endoscopic clips, and the ESD was halted. The patient was referred to our hospital, and ESD was retried. There was severe fibrosis around the lesion, and injections into the submucosal layer were difficult. In addition, it was not possible to identify the submucosal layer, and making an oral-side incision caused a large perforation along the incision line. As continuing the submucosal dissection with an endoknife was considered difficult, the lesion was finally resected with hybrid ESD using a snare. The perforation was closed using polyglycolic acid (PGA) sheets and fibrin glue. Endoscopy performed 6 days later showed that the defect had been closed, and no contrast leakage was detected. Follow-up endoscopy conducted 3 months after the ESD showed ulcer healing at the dissection site and scar formation, but no residual tumor or esophageal stricture was noted. Our experience suggests that the use of PGA sheets with fibrin glue is a feasible, safe, and effective way of treating large esophageal perforations during ESD.

Esophageal stricture is a major problem for patients with large superficial esophageal squamous cell neoplasms (SESCNs) after endoscopic submucosal dissection (ESD). Although many measures could be used as prophylaxis for post-ESD strictures, a well-accepted method has not yet been established. We propose using a triamcinolone-soaked polyglycolic acid sheet plus fully covered metal stent (TS-PGA+FCMS) as a novel method to prevent stricture formation after large esophageal ESD. From June 2016 to May 2017, nine patients with SESCNs (≥3/4 of the esophageal circumference) who underwent TS-PGA+FCMS placement immediately after ESD and did not require additional surgical resection were enrolled in this case series. All stents were removed 4-6 weeks post-ESD. The sizes of mucosal defects in 9 patients were 3/4 (n = 1), 4/5 (n = 2), 1/1 (n = 6). The average size of resection was 90.0 mm (range: 60-140 mm). The incidence of stricture was 33.3% (3/9) of patients. No stricture occurred in 3 patients with noncircumferential resection, while stricture occurred in 50% (3/6) patients with circumferential resection. The median number of EBD sessions was 4 (range: 3-4 sessions). No adverse events or recurrences were observed during the median follow-up period of 15.2 months (range: 12-22 months). The TS-PGA+FCMS method is safe and may decrease the incidence of esophageal stricture and the number of EBD sessions after large esophageal ESD.

Mucosal vaccine delivery systems have paramount importance for the induction of mucosal antibody responses. Two studies were conducted to evaluate immunogenicity of inactivated AIV antigens encapsulated in poly(D,L-lactide-co-glycolide) (PLGA) nanoparticles (NPs). In the first study, seven groups of specific pathogen free (SPF) layer-type chickens were immunized subcutaneously at 7-days of age with different vaccine formulations followed by booster vaccinations two weeks later. Immune responses were profiled by measuring antibody (Ab) responses in sera and lachrymal secretions of vaccinated chickens. The results indicated that inactivated AIV and CpG ODN co-encapsulated in PLGA NPs (2x NanoAI+CpG) produced higher amounts of hemagglutination inhibiting antibodies compared to a group vaccinated with non-adjuvanted AIV encapsulated in PLGA NPs (NanoAI). The tested adjuvanted NPs-based vaccine (2x NanoAI+CpG) resulted in higher IgG responses in the sera and lachrymal secretions at weeks 3, 4 and 5 post-vaccination when immunized subcutaneously. The incorporation of CpG ODN led to an increase in Ab-mediated responses and was found useful to be included both in the prime and booster vaccinations. In the second study, the ability of chitosan and mannan coated PLGA NPs that encapsulated AIV and CpG ODN was evaluated for inducing antibody responses when delivered via nasal and ocular routes in one-week-old SPF layer-type chickens. These PLGA NPs-based and surface modified formulations induced robust AIV-specific antibody responses in sera and lachrymal secretions. Chitosan coated PLGA NPs resulted in the production of large quantities of lachrymal IgA and IgG compared to mannan coated NPs, which also induced detectable amounts of IgA in addition to the induction of IgG in lachrymal secretions. In both mucosal and subcutaneous vaccination approaches, although NPs delivery enhanced Ab-mediated immunity, one booster vaccination was required to generate significant amount of Abs. These results highlight the potential of NPs-based AIV antigens for promoting the induction of both systemic and mucosal immune responses against respiratory pathogens., Competing Interests: The authors have declared that no competing interests exist.

Glioblastoma multiforme (GBM) is the most common primary malignant brain tumor. Despite available therapeutic options, the prognosis for patients with GBM remains very poor. We hypothesized that the intra-operative injection of a photopolymerizable hydrogel into the tumor resection cavity could sustain the release of the anti-cancer drug paclitaxel (PTX) encapsulated in poly (lactic-co-glycolic acid) (PLGA) nanoparticles and prevent GBM recurrence. The tumor was resected 13 days after implantation and a pre-gel solution composed of polyethylene glycol dimethacrylate (PEG-DMA) polymer, a photoinitiator and PTX-loaded PLGA nanoparticles (PTX PLGA-NPs) was injected into the tumor resection cavity. A solid gel filling the whole cavity was formed immediately by photopolymerization using a 400 nm light. PTX in vitro release study showed a burst release (11%) in the first 8 h and a sustained release of 29% over a week. In vitro, U87 MG cells were sensitive to PTX PLGA-NPs with IC 50 level of approximately 0.010 μg/mL. The hydrogel was well-tolerated when implanted in the brain of healthy mice for 2 and 4 months. Administration of PTX PLGA-NPs-loaded hydrogel into the resection cavity of GBM orthotopic model lead to more than 50% long-term survival mice (150 days) compared to the control groups (mean survival time 52 days). This significant delay of recurrence is very promising for the post-resection treatment of GBM., (Copyright © 2018 Elsevier B.V. All rights reserved.)

Oxytocin is a promising candidate for the treatment of social-deficit disorders such as Autism Spectrum Disorder, but oxytocin cannot readily pass the blood-brain barrier. Moreover, oxytocin requires frequent dosing as it is rapidly metabolized in blood. We fabricated four polymeric nanoparticle formulations using poly(lactic-co-glycolic acid) (PLGA) or bovine serum albumin (BSA) as the base material. In order to target them to the brain, we then conjugated the materials to either transferrin or rabies virus glycoprotein (RVG) as targeting ligands. The formulations were characterized in vitro for size, zeta potential, encapsulation efficiency, and release profiles. All formulations showed slightly negative charges and sizes ranging from 100 to 278 nm in diameter, with RVG-conjugated BSA nanoparticles exhibiting the smallest sizes. No formulation was found to be immunogenic or cytotoxic. The encapsulation efficiency was ≥75% for all nanoparticle formulations. Release studies demonstrated that BSA nanoparticle formulation exhibited a faster initial burst of release compared to PLGA particles, in addition to later sustained release. This initial burst release would be favorable for clinical dosing as therapeutic effects could be quickly established, especially in combination with additional sustained release to maintain the therapeutic effects. Our size and release profile data indicate that RVG-conjugated BSA nanoparticles are the most favorable formulation for brain delivery of oxytocin., (Copyright © 2018 Elsevier B.V. All rights reserved.)

Recently, chitosan-based nanoparticles with mucoadhesive properties emerged as a strategy for mucosal drug release. This study aimed to characterize the interaction of mucoadhesive system chitosancoated PLGA nanoparticles (NPMA) with fish external mucus. NP suspensions with fluorescent probe were prepared and characterized by size, polydispersity, zeta potential and pH measures. In post-exposure fish were observed an increase in fluorescence imaging over time and it was significantly influenced by NPMA concentration. We also observed the main predominance the fluorescence in the spleen, followed by liver, gill and other tissues. The use of mucoadhesive nanocarriers becomes an alternative for administration of drugs and immunomodulators in immersion systems since the nanosystem can adhere to the mucosal surface of the fish with little residual effect in the water., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

Resistance to antiepileptic drugs (AEDs) is a major clinical problem. The overexpression of P-glycoprotein (Pgp), one of the main transporters limiting the entry of xenobiotics into the brain, is among the factors contributing to the AED resistance. Presently, there is no consensus on the interaction of carbamazepine (CBZ) with the Pgp. This study investigates the effect of the Pgp inhibitor verapamil on the anticonvulsant effect of CBZ and its nanoparticulate formulation in the rat model of isoniazid-induced epilepsy. Verapamil significantly increased the anticonvulsant effect of CBZ and reduced its effective dose by at least 30% (from 30 mg/kg to 20 mg/kg). Binding of carbamazepine to the poloxamer 188-coated PLGA nanoparticles enabled a 30-fold increase of its anticonvulsive effect, as compared to the free drug. The inhibition of Pgp did not influence the effectivity of carbamazepine encapsulated in nanoparticles., (Copyright © 2018 Elsevier B.V. All rights reserved.)

A delivery system based on poly(lactic-co-glycolic acid) polymer (PLGA) microparticles has been developed for parenteral administration of the local anesthetic prilocaine in its free base form. Both drug-free and drug-loaded microparticles, prepared by a double-emulsion-evaporation method, were characterized for mean size by Laser Diffraction Analysis, while their morphology was investigated by scanning electron microscopy. The preparation technique allowed obtainment of homogeneous microparticles of about 25 µm diameter, suitable for subcutaneous administration. The encapsulation efficiency, determined by both direct and indirect methods, was around 36-38%. Differential Scanning Calorimetry was used to characterize the solid state of the raw materials, assess drug-polymer compatibility and miscibility and highlight possible modifications of the components induced by the preparation method. In vitro release studies showed a sustained release profile, with about 80% of drug released after the first 24 h. The anesthetic effect of the formulation was evaluated in vivo on rats, according to the test of cutaneous trunci muscle reflex. Administration of prilocaine base as PLGA microparticles allowed to significantly enhance both extent (60% AUC increase) and duration (100% increase) of the anesthetic effect in the animal model, in comparison with the equivalent dose of prilocaine hydrochloride aqueous solution., (Copyright © 2018 Elsevier B.V. All rights reserved.)

Stromal vascular fraction (SVF) contains a small number of mesenchymal stem cells and has been used as a treatment for osteoarthritis and cartilage injury. Due to limited evidence of successful cartilage regeneration with injected stem cell therapies, there is interest in combining cellular therapies with injectable scaffolding materials to increase intra-articular residence times of stem cells and improve tissue regeneration. However, the safety of intra-articular injection of SVF combined with injectable scaffolds is unestablished. Also, it is unclear if SVF therapy is superior to more easily prepared biologics, such as platelet-rich plasma (PRP). The purpose of this study was to assess the safety of SVF when combined with an injectable poly(L-lactide-co-glycolide) nanofiber scaffold and to provide a comparison of SVF therapy to PRP. A total of 12 Beagles had osteochondral defects created in both medial femoral condyles and 4 dogs each were allocated to treatment groups of SVF ( n  = 4), SVF plus PLGA scaffolding ( n  = 4), or leukoreduced PRP ( n  = 4). One knee in each dog received treatment, and the contralateral knee was sham treated with saline. Dogs were assessed over a 6-month period, and outcome measures included functional, radiographic, biochemical, and histological assessments. PRP treatment resulted in improvements in lameness scores and objective kinetic assessments of function. There were no statistically significant improvements in function, cartilage biochemical composition, or histology for SVF-treated knees. The combination of SVF and the injectable PLGA scaffold had worse outcomes than other groups including sham treatment based upon functional, biochemical, and histological assessments, raising concerns over the safety of this scaffold for intra-articular injection., Competing Interests: Disclosure The authors report no conflicts of interest in this work., (Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.)

Polymer microparticles are widely used as acellular drug delivery platforms in regenerative medicine, and have emerging potential as cellular scaffolds for therapeutic cell delivery. In the clinic, PLGA microparticles are typically administered intramuscularly or subcutaneously, with the clinician and clinical application site determining the precise needle gauge used for delivery. Here, we explored the role of needle diameter in microparticle delivery yield, and develop a modified viscosity formulation to improve microparticle delivery across a range of clinically relevant needle diameters. We have identified an optimal biocompatible formulation containing 0.25% pluronic F127 and 0.25% carboxymethyl cellulose, which can increase delivery payload to 520% across needle gauges 21-30G, and note that needle diameter impacts delivery efficacy. We use this formulation to increase the delivery yield of PLGA microparticles, and separately, PLGA-cell scaffolds supporting viable mesenchymal stem cells (MSCs), demonstrating the first in vitro delivery of this cell scaffold system. Together, these results highlight an optimal formulation for the delivery of microparticle and microparticle-cell scaffolds, and illustrate how careful choice of delivery formulation and needle size can dramatically impact delivery payload., (Crown Copyright © 2018. Published by Elsevier B.V. All rights reserved.)

Cryptococcus neoformans is one of the most lethal fungi causing mortality across the globe. Immuno-competent patients and patients taking immuno-suppressive medications are extremely susceptible to its infection. For effective removal of cryptococcal burden, there is an urgent need for new forms of therapy. In the present study, we have explored the potential effects of amphotericin B (AMB) and fluconazole (FLC) in combination, against cryptococcosis in Swiss albino mice. To enhance the therapeutic potential of the tested drugs, they were entrapped into fibrin microspheres; a dual delivery vehicle comprising of poly-lactide co-glycolide (PLGA) microsphere that was additionally encapsulated into the fibrin cross-linked plasma bead. Dynamics of fibrin microspheres included survival and fungal burden in lung, liver and spleen of treated mice. While each drug was effective in combination or alone, prominent additive potential of AMB and FLC were clearly observed when used in fibrin microsphere. Significant reduction in fungal burden and increase in survival rate of AMB + FLC-fibrin microspheres treated mice shows an extensive accessibility of both tested drugs without any side-effects. A full potential of two-drug combination encapsulated in fibrin microspheres proposes an effective approach of safe delivery to the target site in their intact form and decrease the drug associated toxicities., (Copyright © 2018 Elsevier B.V. All rights reserved.)

One of the economically important diseases in the poultry industry is Marek's disease (MD) which is caused by Marek's disease virus (MDV). The use of current vaccines provides protection against clinical signs of MD in chickens. However, these vaccines do not prevent the transmission of MDV to susceptible hosts, hence they may promote the development of new virulent strains of MDV. This issue persuaded us to explore alternative approaches to control MD in chickens. Induction of innate responses at the early stage of life in the chicken may help to prevent or reduce MDV infection. Further, prophylactic use of Toll-like receptor ligands (TLR-Ls) has been shown to generate host immunity against infectious diseases. In this regard, encapsulation of TLR-Ls in Poly(d, l-lactic-co-glycolic acid) (PLGA) may further enhance host responses by controlled release of TLR-Ls for an extended period. Hence, in the current study, protective effects of encapsulated TLR4 and TLR21 ligands, LPS and CpG, respectively, were investigated against MD. Results indicated that administration of encapsulated CpG and LPS first at embryonic day (ED) 18, followed by post-hatch at 14 days-post infection (dpi) intramuscularly, diminished tumor incidence by 60% and 42.8%, respectively at 21dpi compared to the MDV only group. In addition, analysis of cytokine gene profiles of interferon (IFN)-α, IFN-β, IFN-γ, inducible nitric oxide synthase (iNOS), interleukin (IL)-1β, IL-18 and IL-10 in spleen and bursa of Fabricius at different time points suggests that TLR-Ls possibly triggered host responses through the expression of IL-1β and IL-18 to reduce tumor formation. However, further studies are needed to explore the role of these pro-inflammatory cytokines and other influencing elements like lymphocytes in the hindrance of tumor development by TLR-Ls treatment in chickens., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

For patient convenience, sustained release Adefovir Poly-d,l-lactic-co-glycolic acid (PLGA) microspheres were formulated to relieve the daily use of the drug which is a problem for patients treated from chronic hepatitis-B. PLGA microspheres were prepared and characterized by entrapment efficiency, particle size distribution and scanning electron microscopy (SEM). In-vitro release and in-vivo studies were carried out. Factors such as drug: polymer ratio, polymer viscosity and polymer lactide content were found to be important variables for the preparation of PLGA Adefovir microspheres. Fourier transform infrared (FTIR) analysis and differential scanning calorimetry (DSC) were performed to determine any drug-polymer interactions. One way analysis of variance (ANOVA) was employed to analyze the pharmacokinetic parameters after intramuscular injection of the pure drug and the selected PLGA microspheres into rats. FTIR and DSC revealed a significant interaction between the drug and the polymer. Reports of SEM before and after 1 and 24 h release showed that the microspheres had nonporous smooth surface even after 24 h release. The entrapment efficiency ranged between 55.83 and 86.95% and in-vitro release studies were continued for 16, 31 and 90 days. The pharmacokinetic parameters and statistical analysis showed a significant increase in the T max, AUC 0-t and MRT, and a significant decrease in the C max of the tested formulation (p < 0.05). Results demonstrated that PLGA Adefovir microspheres could be used for long-term treatment of chronic hepatitis-B instead of the daily dose used by the patient., (Copyright © 2018 Elsevier B.V. All rights reserved.)

Tumor pH detection and pH value change monitoring have been of great interest in the field of nanomedicine. In this study, a pH-sensitive near-infrared fluorescence probe SiRB (Si-rhodamine and Boronic acid group) was synthesized by introducing a boronic acid group into the silicon rhodamine structure. ICG (Indocyanine green) as the fluorescence internal standard and SiRB were loaded into PLGA (poly lactic-co-glycolic acid) to form PLGA-SiRB-ICG nanoparticle. The experiments showed that the size of the nanoparticle was about 90 nm, which can reach tumor passively by enhancing permeability and retention effect. PLGA in the acidic environment will accelerate the release of cleavage, and the fluorescence ratio of the two probes can reflect the specific pH value in the tumor. The results indicated that the nanoparticle could quantitatively measure the pH value of the tumor site, which is expected to be used in tumor research and treatment., (Copyright © 2018 Elsevier B.V. All rights reserved.)

The ability of glucagon-like peptide-1 analogs to enhance glucose-dependent insulin secretion and to inhibit β cell apoptosis could be of potential benefit for islet transplantation. In this study, we investigated the effect of sustained local delivery of exenatide, a synthetic exendin-4, on the in vitro viability and function of encapsulated porcine islets. Prior to encapsulation, we fabricated exenatide-loaded poly(latic-co-glycolic acid) microspheres, and investigated their release behavior with different initial drug-loading amounts. Exenatide-loaded microspheres, exhibiting a sustained release over 21 days, were subsequently chosen and co-encapsulated with porcine islets in alginate microcapsules. During the 21-day period, the islets co-encapsulated with the exenatide-loaded microspheres exhibited improved survival and glucose-stimulated insulin secretion, compared to those without. This suggested that the intracapsular sustained delivery of exenatide via microspheres could be a promising strategy for improving survival and function of microencapsulated porcine islets for islet xenotransplantation.

To promote the specific targeting and elimination of CD44-positive cancer cells, berberine chloride (BRB)-encapsulated hyaluronic acid-grafted poly(lactic-co-glycolic acid) copolymer (BRB-d(HA)-g-PLGA) nanoparticles (NPs) were prepared. The targeted action of these NPs was compared to non-targeted BRB-loaded PLGA NPs and bulk BRB. The in vitro studies demonstrated faster release of BRB and increased cytotoxicity of BRB-d(HA)-g-PLGA NPs in Hela and MCF-7 cells in comparison to BRB-PLGA NPs and bulk BRB. The uptake of BRB-d(HA)-g-PLGA NPs was increased in case of MCF-7 cells as compared to HeLa cells owing to the higher expression of CD44 receptors on MCF-7 cells. The CD44 receptor-mediated uptake of these NPs was confirmed through competitive inhibition experiments. The in vitro results were further validated in vivo in Ehrlich Ascites Carcinoma (EAC)-bearing mice. EAC-bearing mice were injected intravenously with these NPs and the results obtained were compared with that of BRB-PLGA NPs and bulk BRB. BRB-d(HA)-g-PLGA NPs were found to significantly enhance apoptosis, sub-G1 content, life span, mean survival time, and ROS levels in EAC cells with subsequent decrease in mitochondrial membrane potential and tumor burden ion tumor-bearing mice. Taking into account the findings of in vitro and in vivo studies, the enhanced and targeted anti-tumor activity of HA-grafted PLGA copolymer-encapsulated NPs of BRB cannot be negated. Therefore, HA-grafted nanoparticle-based delivery of BRB may offer a promising and improved alternative for anti-tumor therapy.

The present in-vivo study investigated the behavior and performance of differently charged poly(lactic‑co‑glycolic) acid microparticles (PLGA MP) as vaccination platform. For this purpose, particles loaded with ovalbumin (OVA) as model antigen were subcutaneously (s.c.) injected in SKH1 mice. The utilized SKH1 hairless mice exhibit a fully operative immune system and allow parallel imaging investigations due to the lack of hair. Usage of this species enabled the combination of two investigations within a single study protocol, namely noninvasive in-vivo imaging and immune responses directed towards the antigen. All treatments were well tolerated, no safety drop-outs occurred. The fate of the model antigen OVA as well as the PLGA particles was monitored using a dual dye approach (CF660C & DiR) by multispectral fluorescence imaging (msFI). A depot effect for the OVA antigen adsorbed to the MP surface could be observed for the positively charged MPs. The immune response against OVA was then analyzed. OVA alone did not induce an immune response, whereas the positively charged as well as the neutral MP induced a strong and consistent humoral immune response with a clear favor of IgG1 over IgG2a subclass antibodies. In contrast, negatively charged MP were not able to induce measurable antibody responses. Cellular immune response was weak and inconsistent for all treated groups, which verifies previous in-vitro results conducted with the herein described microparticulate antigen platform. In conclusion, the characterization of the in-vivo performance yielded valuable information about antigen and carrier fate after application. The presented adjuvant platform is capable of inducing strong T H 2 dominated immune responses characterized by enhanced IgG1 subclass titers which are critical for vaccines aimed at promoting induction of neutralizing antibodies., (Copyright © 2018 Elsevier B.V. All rights reserved.)

Restoration of the Chol homeostasis in the Central Nervous System (CNS) could be beneficial for the treatment of Huntington's Disease (HD), a progressive, fatal, adult-onset, neurodegenerative disorder. Unfortunately, Chol is unable to cross the blood-brain barrier (BBB), thus a novel strategy for a targeted delivery of Chol into the brain is highly desired. This article aims to investigate the production of hybrid nanoparticles composed by Chol and PLGA (MIX-NPs) modified with g7 ligand for BBB crossing. We described the impact of ratio between components (Chol and PLGA) and formulation process (nanoprecipitation or single emulsion process) on physico-chemical and structural characteristics, we tested MIX-NPs in vitro using primary hippocampal cell cultures evaluating possible toxicity, uptake, and the ability to influence excitatory synaptic receptors. Our results elucidated that both formulation processes produce MIX-NPs with a Chol content higher that 40%, meaning that Chol is a structural particle component and active compound at the same time. The formulation strategy impacted the architecture and reorganization of components leading to some differences in Chol availability between the two types of g7 MIX-NPs. Our results identified that both kinds of MIX-NPs are efficiently taken up by neurons, able to escape lysosomes and release Chol into the cells resulting in an efficient modification in expression of synaptic receptors that could be beneficial in HD., (Copyright © 2018 Elsevier B.V. All rights reserved.)

Oral administration of insulin increases patient comfort and could improve glycemic control thanks to the hepatic first passage. However, challenges remain. The current approach uses poly (d, lactic-co-glycolic) acid (PLGA) nanoparticles (NPs), an effective drug carrier system with a long acting profile. However, this system presents a bioavailability of less than 20% for insulin encapsulation. In this context, physico-chemical parameters like surface charge could play a critical role in NP uptake by the intestinal barrier. Therefore, we developed a simple method to modulate NP surface charge to test its impact on uptake in vitro and finally on NP efficiency in vivo. Various NPs were prepared in the presence (+) or absence (-) of polyvinyl alcohol (PVA), sodium dodecyl sulfate (SDS), and/or coated with chitosan chloride. In vitro internalization was tested using epithelial culture of Caco-2 or using a co-culture (Caco-2/RevHT29MTX) by flow cytometry. NPs were then administered by oral route using a pharmaceutical complex vector (100 or 250 UI/kg) in a diabetic rat model. SDS-NPs (-42 ± 2 mV) were more negatively charged than -PVA-NPs (-22 ± 1 mV) and chitosan-coated NPs were highly positively charged (56 ± 2 mV) compared to +PVA particles (-2 ± 1 mV), which were uncharged. In the Caco-2 model, NP internalization was significantly improved by using negatively charged NPs (SDS NPs) compared to using classical NPs (+PVA NPs) and chitosan-coated NPs. Finally, the efficacy of insulin SDS-NPs was demonstrated in vivo (100 or 250 UI insulin/kg) with a reduction of blood glucose levels in diabetic rats. Formulation of negatively charged NPs represents a promising approach to improve NP uptake and insulin bioavailability for oral delivery., (Copyright © 2018 Elsevier B.V. All rights reserved.)

It is difficult to effectively eradicate C. albicans using traditional antifungal agents, mainly because the low permeability of the C. albicans cell wall creates strong drug resistance. The aim of this study was to investigate the synergistic fungicidal effect and the underlying mechanisms of low-frequency and low-intensity ultrasound combined with a treatment of amphotericin B-loaded nanoparticles (AmB-NPs) against C. albicans. AmB-NPs were prepared by a poly(lactic-co-glycolic acid) (PLGA) double emulsion method. C. albicans was treated by AmB-NPs combined with 42 kHz ultrasound irradiation at an intensity of 0.30 W/cm 2 for 15 min. The results demonstrate that the application of ultrasound enhanced the antibacterial effectiveness of AmB-NPs (P < 0.01), and the antifungal efficiency increased significantly with increasing AmB concentration of drug-loaded nanoparticles under ultrasonic irradiation. Additionally, the mycelial morphology of C. albicans suffered from the most severe damage and loss of normal microbial morphology after the combined treatment of AmB-NPs and ultrasound, as revealed by electron microscope. Furthermore, we verified the safe use of low-frequency ultrasound on exposed skin and discussed the potential mechanism of ultrasound enhanced fungicidal activity. The results reveal that the mechanism may be associated with the ultrasound cavitation effect and an increase in intracellular reactive oxygen species., (Copyright © 2018 Elsevier B.V. All rights reserved.)

Etoposide-loaded poly(lactic-co-glycolic acid) implants were developed for intravitreal application. Implants were prepared by a solvent-casting method and characterized in terms of content uniformity, morphology, drug-polymer interaction, stability, and sterility. In vitro drug release was investigated and the implant degradation was monitored by the percent of mass loss. Implants were inserted into the vitreous cavity of rabbits' eye and the in vivo etoposide release profile was determined. Clinical examination and the Hen Egg Test-Chorioallantoic Membrane (HET-CAM) method were performed to evaluate the implant tolerance. The original chemical structure of the etoposide was preserved after incorporation in the polymeric matrix, which the drug was dispersed uniformly. In vitro, implants promoted sustained release of the drug and approximately 57% of the etoposide was released in 50 days. In vivo, devices released approximately 63% of the loaded drug in 42 days. Ophthalmic examination and HET-CAM assay revealed no evidence of toxic effects of implants. These results tend to show that etoposide-loaded implants could be potentially useful as an intraocular etoposide delivery system in the future.

Background: Norquetiapine ( N -desalkyl quetiapine, NQ) is an active metabolite of quetiapine with stable pharmacokinetic and pharmacological properties. However, its short half-life is a drawback for clinical applications, and long-acting formulations are required., Purpose: The objectives of this study were to prepare improved entrapment efficiency NQ freebase microspheres by the solvent evaporation method with poly(d,l-lactic-co-glycolic acid) (PLGA) as a release modulator and to evaluate their physicochemical and in vitro/in vivo release properties., Methods: NQ freebase PLGA (1:5 w/w) formulations were prepared by the oil-in-water (o/w) emulsion-solvent evaporation method. A solution of the drug and PLGA in 9:1 v/v dichloromethane:ethanol was mixed with 0.2% polyvinyl alcohol and homogenized at 2,800 rpm. The emulsion was stirred for 3 h to dilute and evaporate the solvent. After that, the resulting product was freeze-dried. Drug-loading capacity was measured by the validated RP-HPLC method. The surface morphology of the microspheres was observed by scanning electron microscopy (SEM), and the physicochemical properties were evaluated by differential scanning calorimetry, powder X-ray diffraction, and Fourier-transform infrared spectroscopy particle size distribution. The in vitro dissolution test was performed using a rotary shaking bath at 37°C, with constant shaking at 50 rpm in sink condition., Results: The NQ freebase microspheres prepared by o/w emulsion-solvent evaporation showed over 30% efficiency. NQ was confirmed to be amorphous in the microspheres by powder X-ray diffraction and differential scanning calorimetry. Special chemical interaction in the microspheres was not observed by FT-IR. The in vitro dissolution test demonstrated that the prepared microspheres' release properties were maintained for more than 20 days. The in vivo test also confirmed that the particles' long acting properties were maintained. Therefore, good in vitro-in vivo correlation was established., Conclusion: In this study, NQ freebase-PLGA microspheres showed potential for the treatment of schizophrenia for long-periods., Competing Interests: Disclosure The authors report no conflicts of interest in this work.

We evaluate poly (d,l-lactide-co-glycolide) (PLGA) nanoparticles embedding inorganic molybdenum octahedral cluster for photodynamic therapy of cancer (PDT). Tetrabutyl ammonium salt of Mo 6 Br 14 cluster unit, (TBA) 2 Mo 6 Br 14 , presents promising photosensitization activity in the destruction of targeted cancer cells. Stable cluster loaded nanoparticles (CNPs) were prepared by solvent displacement method showing spherical shapes, zeta potential values around -30 mV, polydispersity index lower than 0.2 and sizes around 100 nm. FT-IR and DSC analysis revealed the lack of strong chemical interaction between the cluster and the polymer within the nanoparticles. In vitro release study showed that (TBA) 2 Mo 6 Br 14 was totally dissolved in 20 min, while CNPs were able to control the release of encapsulated cluster. In vitro cellular viability studies conducted on A2780 ovarian cancer cell line treated up to 72 h with cluster or CNPs did not show any sign of toxicity in concentrations up to 20 µg/ml. This concentration was selected for photo-activation test on A2780 cells and CNPs were able to generate oxygen singlet resulting in a decrease of the cellular viability up to 50%, respectively compared to non-activated conditions. This work presents (TBA) 2 Mo 6 Br 14 as a novel photosensitizer for PDT and suggests PLGA nanoparticles as an efficient delivery system intended for tumor targeting., (Copyright © 2018 Elsevier B.V. All rights reserved.)

Curcumin has shown promising inhibitory activity against HER-2-positive tumor cells in vitro but suffers from poor oral bioavailability in vivo. Our lab has previously developed a polymeric microparticle formulation for sustained delivery of curcumin for chemoprevention. The goal of this study was to examine the anticancer efficacy of curcumin-loaded polymeric microparticles in a transgenic mouse model of HER-2 cancer, Balb-neuT. Microparticles were injected monthly, and mice were examined for tumor appearance and growth. Initiating curcumin microparticle treatment at 2 or 4 weeks of age delayed tumor appearance by 2-3 weeks compared to that in control mice that received empty microparticles. At 12 weeks, abnormal (lobular hyperplasia, carcinoma in situ, and invasive carcinoma) mammary tissue area was significantly decreased in curcumin microparticle-treated mice, as was CD-31 staining. Curcumin treatment decreased mammary VEGF levels significantly, which likely contributed to slower tumor formation. When compared to saline controls, however, blank microparticles accelerated tumorigenesis and curcumin treatment abrogated this effect, suggesting that PLGA microparticles enhance tumorigenesis in this model. PLGA microparticle administration was shown to be associated with higher plasma lactic acid levels and increased activation of NF-κΒ. The unexpected side effects of PLGA microparticles may be related to the high dose of the microparticles that was needed to achieve sustained curcumin levels in vivo. Approaches that can decrease the overall dose of curcumin (for example, by increasing its potency or reducing its clearance rate) may allow the development of sustained release curcumin dosage forms as a practical approach to cancer chemoprevention.

In this study, a reevaluation of the in vivo release phases from long-release PLGA-based microspheres is presented, leading to a better characterization of the plasma concentrations/time profile. Microspheres were designed for intramuscular injection releasing a cyclic somatostatin analog over 70 days. Clinical study was performed in 64 healthy subjects receiving a subcutaneous dose of an immediate release solution as reference formulation and an intramuscular injection of microspheres as test formulation. The in vivo input curve was obtained by numerical deconvolution. Results showed that double Weibull function could not fit correctly the tri-phasic (burst, lag, and erosion) in vivo input profile typical for PLGA-based formulations, due to a change in the drug release trend in the terminal phase. Triple Weibull showed a significant improvement in the curve fitting, each term being assigned to one of the following phases: initial (burst/lag), erosion, and terminal phase of drug release. The existence of the additional terminal phase was confirmed by a mechanistic approach as well, which denoted that this phase was, most probably, a consequence of the release mechanism change from erosion to diffusion controlled. The same model demonstrated that the burst release was as well influenced by the polymer swelling, while currently existing theories state that the burst phase is mainly determined by the dissolution of immediately available drug substance and diffusion through surface related pores., (Copyright © 2017 Elsevier B.V. All rights reserved.)

Frequent intravitreal injections are currently used to overcome the ocular barriers and provide sufficient drug to the posterior eye segment. However, intravitreal injections have been associated with a number of complications and high treatment costs. To overcome these limitations, peptide-loaded poly(d,l-lactic-co-glycolic acid) nanoparticles (PLGA NPs) were developed using the nanoprecipitation technique and were optimized via Box-Behnken Design (BBD) and Response Surface Methodology (RSM). Developed NPs were evaluated for potential toxicity and cell apoptosis using the zebrafish embryo toxicity (ZET) model with titanium dioxide NPs and ethanol (1% v/v) serving as positive controls. Developed NPs had a size of 75.6-153.8 nm, a polydispersity index between 0.11 and 0.25 and a zeta potential of -9.4 to -46.0 mV. Loaded peptide was found to be stable under various experimental conditions tested. BBD and RSM were validated through the characterization of optimized formulations. Survival and hatching rates of NP-treated zebrafish 0-144 h post-fertilization were found to be normal with no significant malformations. Cellular apoptosis studies also endorsed the non-cytotoxic nature of the NPs. The overall results indicate that optimized PLGA nanoparticles could be a promising platform for efficient peptide delivery to the posterior segment of the eye.

Background Context: Targeted delivery of osteoinductive bone morphogenetic proteins (eg, GDF5) in bioresorbable calcium phosphate cement (CPC), potentially suitable for vertebroplasty and kyphoplasty of osteoporotic vertebral fractures, may be required to counteract augmented local bone catabolism and to support complete bone regeneration. The biologically optimized GDF5 mutant BB-1 may represent an attractive drug candidate for this purpose., Purpose: The aim of the current study was to test an injectable, poly(l-lactide-co-glycolide) acid (PLGA) fiber-reinforced, brushite-forming CPC containing low-dose BB-1 in a sheep lumbar osteopenia model., Study Design/ Setting: This is a prospective experimental animal study., Methods: Bone defects (diameter 5 mm) were generated in aged, osteopenic female sheep and were filled with fiber-reinforced CPC alone (L4; CPC+fibers) or with CPC containing different dosages of BB-1 (L5; CPC+fibers+BB-1; 5, 100, and 500 µg BB-1; n=6 each). The results were compared with those of untouched controls (L1). Three and 9 months after the operation, structural and functional effects of the CPC (±BB-1) were analyzed ex vivo by measuring (1) bone mineral density (BMD); (2) bone structure, that is, bone volume/total volume (BV/TV) (assessed by micro-CT and histomorphometry), trabecular thickness (Tb.Th), and trabecular number (Tb.N); (3) bone formation, that is, osteoid volume/bone volume (OV/BV), osteoid surface/bone surface (OS/BS), osteoid thickness, mineralizing surface/bone surface (MS/BS), mineral apposition rate, and bone formation rate/bone surface; (4) bone resorption, that is, eroded surface/bone surface; and (5) compressive strength., Results: Compared with untouched controls (L1), CPC+fibers (L4) and/or CPC+fibers+BB-1 (L5) significantly improved all parameters of bone formation, bone resorption, and bone structure. These effects were observed at 3 and 9 months, but were less pronounced for some parameters at 9 months. Compared with CPC without BB-1, additional significant effects of BB-1 were demonstrated for BMD, bone structure (BV/TV, Tb.Th, and Tb.N), and bone formation (OS/BS and MS/BS). The BB-1 effects on bone formation at 3 and 9 months were dose dependent, with 100 µg as the potentially optimal dosage., Conclusions: BB-1 significantly enhanced the bone formation induced by a PLGA fiber-reinforced CPC in sheep lumbar osteopenia. A single local dose as low as 100 µg BB-1 was sufficient to augment middle- to long-term bone formation. A CPC containing the novel GDF5 mutant BB-1 may thus represent an alternative to the bioinert, supraphysiologically stiff polymethylmethacrylate cement presently used to treat osteoporotic vertebral fractures by vertebroplasty and kyphoplasty., (Copyright © 2017 Elsevier Inc. All rights reserved.)

Although vitamin D3 (VD3), which is the main form of vitamin D, can be produced in human skin under the sunlight, vitamin D deficiency emerged as a major public health problem worldwide. Mainly, oral supplements or vitamin D-fortified foods are distributed to help supplementation of vitamin D. However, those oral methods are limitedly supplied in the Middle East countries, and oral absorption has low efficiency due to many barriers and various changes of conditions along the route. Then, it is recommended to take them every day in order to maintain the adequate serum level of vitamin D. Alternatively, transdermal delivery system could provide a convenient way to get sustained supplement of vitamin D by its advantages like avoiding first-pass effect of the liver and providing release for long periods of time. In this study, we introduced transdermal delivery system for sustained vitamin D release using coating microneedles that easily pierce the skin layer with enough mechanical strength and allow the localization of drugs within the dermal region. According to the experimental results, poly (lactic-co-glycolic acid) (PLGA) successfully encapsulated VD3 as a nanoparticle form with appropriate properties for transdermal delivery such as size distribution, skin compatibility, and effective release of encapsulated compound. Finally, PVD3 layers coated on solid microneedles were completely dissolved into intradermal region in porcine skin model and revealed better performance for VD3 release into plasma compared to ointment base transdermal method.

In this study, angelica sinensis polysaccharide (ASP) was encapsulated into the Poly (lactic-co-glycolicacid) (PLGA) to constitute the ASP-PLGA. The aim of the study is to obtain optimal encapsulation efficiency of ASP-PLGA by optimizing the preparation conditions and investigate the immunological enhancement activity of ASP-PLGA. To obtain the optimal processing parameters, the parameters, such as the ratio of organic phase (o) to internal water phase (w 1 ), the ratio of external water phase (w 2 ) to organic phase (o) and the concentration of Pluronic F68 (F68) (w/v) were examined through response surface methodology (RSM). The optimum preparation conditions of ASP-PLGA for maximizing encapsulation efficiency (EE) was as follows:ratio of organic phase (o) to internal water phase (w 1 ) at 10:1, ratio of external water phase (w 2 ) to organic phase (o) at 11:1, the concentration of F68 at 0.8% and the experimental EE 67.89±0.48% was achieved. In addition, the results showed that ASP-PLGA could significantly promote the lymphocytes proliferation and increase the ratio of CD4 + to CD8 + T cells compared with ASP and blank PLGA. This study provided strong evidence that the immunological enhancement of ASP was significantly improved through establishing a drug delivery system with PLGA., (Copyright © 2017 Elsevier B.V. All rights reserved.)

PEG-PLGA nanoparticles (NPs) modified with anti-CD133 and tumor-targeting single-chain antibody fragment (scFV-NPs) for systemic delivery of methioninase (METase) and pemetrexed for gastric carcinoma were successfully formulated. The structure characterization and biological functions of METase-pemetrexed-loaded scFV-PEG-PLGA NPs (scFV-METase/pemetrexed-NPs) in vitro were investigated. Functional scFV-PEG-PLGA NPs or PEG-PLGA NPs present low cell cytoxicity in CD133+ SGC7901 cells. scFV-METase/pemetrexed-NPs (scFv-M/P-NP) was more effective in inhibiting tumor growth (including cell growth and migration ability) in CD133 positive expressed gastric cancer cells than METase/pemetrexed-NPs (M/P-NP). Moreover, METase enhanced the inhibitory effect of pemetrexed on thymidylate synthase (TS) synthesis and cell apoptosis. We have demonstrated the application of scFV-targeted PEG-PLGA NPs as a new potential strategy to enhance treatment benefits for gastric carcinoma., (© 2018 The Author(s).)

The use of polymeric nanoparticles as delivery systems is a promising tool to overcome drawbacks related to low aqueous solubility of drugs, which limit their in vivo bioavailability. The aim of this study was to decrease clofazimine (CLZ) toxicity using experimental design to formulate CLZ loaded in PLGA nanoparticles (NPs-CLZ) through a Plackett-Burman design (PBD). A screening PBD was constructed with twelve formulations involving six variables among process and formulation parameters and the selected responses were particle size, polydispersity index (PDI), association efficiency (AE) and drug loading (DL). The formulation was achieved based on the desirability tool, and the obtained NPs-CLZ formulation was characterized regarding morphology, physicochemical properties, in vitro release and cellular studies. Particle size, PDI, AE and DL were found to be 211±3nm, 0.211±0.009, 70±5% and 12±1%, respectively. Physicochemical studies confirmed the absence of chemical interactions between CLZ and other nanoparticles constituents and the amorphous state of CLZ, while morphological analysis revealed the spherical shape of the particles. In vitro release profile of CLZ from NPs-PLGA showed a slow pattern of drug release. Cell viability studies towards intestinal cells revealed that NPs-CLZ did not show CLZ toxicity on Caco-2 and HT29-MTX cells compared to free CLZ solutions. Moreover, CLZ could permeate Caco-2 monolayers substantially at the end of 8h. It can be concluded that the proposed NPs-CLZ represent a promising platform to the oral delivery of CLZ as they were able to decrease its intrinsic toxicity, with improved absorption., (Copyright © 2017 Elsevier B.V. All rights reserved.)

Small-molecule agonists for the Toll-like receptors (TLR) 7 and 8 are effective for the immunotherapy of skin cancer when used as topical agents. Their systemic use has however been largely unsuccessful due to dose-limiting toxicity. We propose a polymer-based nanodelivery system to target resiquimod, a TLR7 ligand, to the lymph node in order to focus the immunostimulatory activity and to prevent a generalized inflammatory response. We demonstrate successful encapsulation of resiquimod in methoxypoly(ethylene glycol)-b-poly(DL-lactic acid) (mPEG-PLA) and mixed poly(DL-lactic-co-glycolic acid) (PLGA)/mPEG-PLA nanoparticles. We show that these particles are taken up mainly by dendritic cells and macrophages, which are the prime initiators of anticancer immune responses. Nanoparticles loaded with resiquimod activate these cells, demonstrating the availability of the immune-stimulating cargo. The unloaded particles are non-inflammatory and do not have cytotoxic activity on immune cells. Following subcutaneous injection in mice, mPEG-PLA and PLGA/mPEG-PLA nanoparticles are detected in dendritic cells and macrophages in the draining lymph nodes, demonstrating the targeting potential of these particles. Thus, polymer-based nanoparticles represent a promising delivery system that allows lymph node targeting for small-molecule TLR7 agonists in the context of systemic cancer immunotherapy., (Copyright © 2017 Elsevier B.V. All rights reserved.)

Aim: To evaluate appropriate and rapid polyglycolic acid sheet (PGAs) covering time using device delivery station system (DDSS)., Methods: This pilot basic study was conducted to evaluate the potential of accurate and rapid PGAs delivery using DDSS. Three 11-mo-old female Beagle dogs were used in this study. Two endoscopic submucosal dissections (ESDs) 4cm in diameter were performed in lesser curvature of middle gastric body and greater curvature of antrum (total 6 ESDs performed). DDSS (3 cm length, 12 mm in outer diameter) has 2 chambers which 16 cm 2 large 2 PGAs were stored, and DDSS was attached post ESD ulcers, respectively. Beriplast P ® (CSL Behring K.K., Tokyo, Japan) (combination of fibrin glue and thrombin) was applied equally to the artificial ulcer, and tight attachment of 2 PGAs with DDSS were completed. The evaluation items were covering times, post ESD bleeding and perforation during ESD., Results: The covering time of PGAs (defined as the duration from the beginning of endoscope insertion into the mouth to the end of the fibrin glue coating process) was 6.07 (4.86-8.29) min. There was no post-ESD bleeding (1-7 d after ESD), and there was no perforation during ESD., Conclusion: DDSS was very useful for rapid delivering and tight attachment of PGAs, and has potentials of multi-purpose delivery station system., Competing Interests: Conflict-of-interest statement: All authors declare that they have no conflicts of interest, and no corporate financing was received.

Campylobacter jejuni (C. jejuni) is a major cause of bacterial food-borne illness in humans. It is considered a commensal organism of the chicken gut and infected chickens serve as a reservoir and shed bacteria throughout their lifespan. Contaminated poultry products are considered the major source of infection in humans. Therefore, to reduce the risk of human campylobacteriosis, it is essential to reduce the bacterial load in poultry products. The present study aimed to evaluate the protective effects of soluble and PLGA-encapsulated oligodeoxynucleotides (ODN) containing unmethylated CpG motifs (E-CpG ODN) as well as C. jejuni lysate as a multi-antigen vaccine against colonization with C. jejuni. The results revealed that oral administration of a low (5 µg) or high (50 µg) dose of CpG resulted in a significant reduction in cecal C. jejuni colonization by 1.23 and 1.32 log 10 (P < .05) in layer chickens, respectively, whereas E-CpG significantly reduced cecal C. jejuni colonization by 1.89 and 1.46 log 10 in layer and broiler chickens at day 22 post-infection (slaughter age in broilers), respectively. Similar patterns were observed for C. jejuni lysate; oral administration of C. jejuni lysate reduced the intestinal burden of C. jejuni in layer and broiler chickens by 2.24 and 2.14 log 10 at day 22 post-infection, respectively. Moreover, the combination of E-CpG and C. jejuni lysate reduced bacterial counts in cecal contents by 2.42 log 10 at day 22 post-infection in broiler chickens. Anti-C. jejuni IgG antibody (Ab) titers were significantly higher for broiler chickens receiving a low or high dose of E-CpG or a low dose of C. jejuni lysate than for chickens receiving the placebo. Furthermore, a positive correlation was observed between serum IgG Ab titers and cecal counts of C. jejuni in these groups. These findings suggest that PLGA-encapsulated CpG or C. jejuni lysate could be a promising strategy for control of C. jejuni in chickens., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

Objective: The objective of this study was to evaluate the feasibility and safety of a polyglycolic acid (PGA) yarn implant for nonthermal ablation of saphenous vein reflux., Methods: In two consecutive cohort studies (TAHOE I and TAHOE II), the feasibility of abolition of great saphenous vein (GSV) reflux by implantation of a PGA yarn was tested under ultrasound guidance in 51 and 30 patients, respectively. The use of tumescent local anesthesia was not required. Graduated compression stockings and thrombosis prophylaxis with low-molecular-weight heparin were used for 2 weeks after intervention in the first study only., Results: Of 81 enrolled patients, 77 (95%) were available at 6-month follow-up. Complete occlusion of the treated GSV was confirmed by duplex ultrasound in all patients except one patient at day 1. In TAHOE II, closure was preserved in a higher percentage of patients at 6 weeks, with 96.4% vs 82.0% in TAHOE I. The 6-month Kaplan-Meier estimated occlusion rates for TAHOE I and TAHOE II were 68% (95% confidence interval [CI], 54%-79%) and 69% (95% CI, 49%-82%), respectively, with an estimated combined occlusion rate of 69% (95% CI, 57%-76%). Kaplan-Meier analysis yielded a combined reflux-free rate of 85% (95% CI, 75%-91%) at 3 months of follow-up and a rate of 81% (95% CI, 71%-88%) at 6 months of follow-up. Venous Clinical Severity Score (VCSS) improved from a combined mean of 4.6 ± 3.1 at baseline to 2.1 ± 2.2 and 1.6 ± 1.9 at 3 and 6 months, respectively (P < .0001 for 3- and 6-month results). In TAHOE II, four patients with venous ulcers healed at an average of 1.3 months after treatment., Conclusions: First-in-human use of an endovenous PGA yarn implant for occlusion of refluxing GSVs proved to be feasible, with no serious adverse events. However, recanalization was observed during a period of 6 months in 31% of patients., (Copyright © 2017 Society for Vascular Surgery. Published by Elsevier Inc. All rights reserved.)

In the development of drugs for intra-articular administration, sustained-release formulations are desirable because it is difficult to maintain the effect of conventional injections due to immediate drug leakage from the joint cavity. In this study, a sustained-release poly(lactic-co-glycolic acid) (PLGA) microsphere formulation for intra-articular administration containing indocyanine green (ICG) as a model drug was prepared to follow its fate after intra-articular administration in rats with a real-time in-vivo imaging system. ICG administered as an aqueous solution leaked from the joint cavity in a short time and was excreted outside the body within 1-3 d. However, ICG in the sustained-release formulation was retained in the joint cavity and released for 2 weeks. Next, a sustained-release formulation containing PLGA microspheres in a hyaluronic acid (HA) gel formulation was prepared. After gradual release in two stages, we could achieve sustained release for a longer period. It is considered that a combination formulation of PLGA microspheres and HA gel can significantly improve the sustained release of a drug administered into the knee joint.

Objective: The incredibly serious problem of Hepatitis B is virus-related chronic liver disease. The conventional preventive treatment of Hepatitis B requires booster dose, which requires repeated administration of the vaccine to the subject. Thus, there is a need to develop a formulation which can eliminate the need of frequent dosing and enhance patient's acquiescence. To prepare single dose nanovaccine of HBsAg by utilizing central composite design for optimization and interaction of independent variables effects on measured response., Methods: Nanovaccines were characterized for particle size, morphology, integrity, internalization, proliferation response and haemocompatibility. Nanoparticles at single and multiple doses were compared with booster dose of alum-HBsAg vaccine and measure the immunological marker and cytokine (interleukin-2 and interferon-Y) levels by ELISA techniques in BALB/c mice., Results: The designed nanoparticles were found to have nanometric size, high entrapment efficiency and retained antigen integrity. Nanoparticles showed maximum proliferation and efficiently internalized by lymph and spleen cell without eliciting significant toxicity and haemocampatible., Conclusion: The comparable data of anti-HBsAg titre between nanovaccine and alum adsorbed HBsAg demonstrated that single dose of nanoparticles is sufficient for production of immunoglobulin plus cytokine levels, maintain immunogenicity at longer period of time and eliminate the booster dose. Nanovaccines trigger immune responses and showing adjuvant properties., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.)

Background: Periodontitis is a localized inflammatory disorder. If not treated timely, the disease can result in loosening and subsequent loss of teeth. In situ hydrogel prepared with phase separation technique has emerged as an attractive alternative for periodontal pocket injection., Objective: Minocycline (MCL)-loaded in situ hydrogel was prepared composed of poly(lactide-coglycolide) (PLGA) and N-methylpyrrolidone (NMP) to improve the topical treatment effect of periodontitis., Method: A series of reasonable and applicable formulations were optimized by investigating their syringeability, viscosity and in vitro drug release. The rheological profiles, antimicrobial activities and pharmacodynamics were further studied to evaluate its effect on periodontitis treatment., Results: The prepared MCL/PLGA hydrogel exhibited the characteristic of Newton fluid with acceptable syringeability. Drug release could last for more than 48 hours with an acceptable "burst release". It also had obvious antimicrobial activities and pharmacodynamics efficiency similar to the commercial product, Parocline®., Conclusion: MCL/PLGA in situ hydrogel may be a promising clinical formulation for periodontitis treatment., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.)