Sclerosing encapsulating peritonitis in a dog with pancreatic ductal adenocarcinoma.

BACKGROUND: Sclerosing encapsulating peritonitis (SEP) is a rare clinical syndrome characterised by fibrosis and thickening of the peritoneum with massive adhesions of the abdominal organs. In humans, abdominal tumours, such as pancreatic adenocarcinoma, can be underlying diseases of SEP. This report describes a case of SEP in a dog with pancreatic ductal adenocarcinoma. CASE PRESENTATION: An 11-year-old male neutered French Bulldog presented with chronic vomiting. Ultrasonography revealed a mass in the centre of the abdomen. A small amount of ascites, interpreted as modified transudate, was present in the abdominal cavity. Computed tomography (CT) revealed peritoneal effusion with a thickened peritonium. Laparoscopy revealed a large nodular lesion occupying the central portion of the abdomen, continuous with the falciform ligament. Histological examination of the biopsy specimens of the mass, abdominal wall, and gastric peritoneum revealed marked fibroplasia with mild lymphoplasmacytic infiltrates. Based on these results, a tentative diagnosis of early stage sclerosing encapsulating peritonitis (SEP) was made. Prednisolone and tamoxifen were administered with the expectation of ameliorating SEP, however, the dog died 61 days post diagnosis. At autopsy, the intestinal loop and mesentery were encased in the fibrous membrane, which is a typical finding in SEP. Histopathology and immunohistochemistry of the samples obtained at autopsy supported the diagnosis of pancreatic ductal adenocarcinoma with peritoneal dissemination and distant metastasis with desmoplasia. The unexpectedly hardened skin, where previously laparoscopic ports were inserted, histologically contained the same carcinoma cells with desmoplasia. CONCLUSIONS: To the best of our knowledge, this is the first report of canine SEP with pancreatic ductal adenocarcinoma that also caused metastasis to port insertion sites as well as distant organs.

IFN-Alpha1 antisense RNA represses human influenza A virus growth in a guinea pig system.

We reported a natural antisense (AS) long non-coding RNA as an important modulator of interferon-Alpha1 (IFNA1) mRNA levels. We showed that IFN-Alpha1 AS promotes IFNA1 mRNA stability by transient duplex formation and inhibition of miR-1270-induced mRNA decay. Here, we performed a proof-of-concept experiment to verify that the AS-mRNA regulatory axis exerts in vivo control of innate immunity. We established a model system for influenza virus infection using guinea pig, which encodes a functional MX1 gene for the type I IFN pathway. This system allowed us to investigate the effects of antisense oligoribonucleotides representing functional domains of guinea pig IFN-Alpha1 AS on gpIFNA1 mRNA levels and, consequently, on viral proliferation in the respiratory tract of influenza virus-infected animals. We demonstrated that pulmonary-administered asORNs inhibited the proliferation of the virus in the animals by modulating IFNA1 mRNA levels. These results indicate that, in light of the proposed actions, asORNs may modulate the level of IFNA1 mRNA in vivo, indicating that IFN-Alpha1 AS plays a pivotal role in determining the outcome of type I IFN responses.

Prevention of neointimal formation after angioplasty using nuclear factor-κB decoy oligodeoxynucleotide-coated balloon catheter in rabbit model.

BACKGROUND: Despite the advent of drug-eluting stents, restenosis after endovascular intervention is still a major limitation in the treatment of cardiovascular disease. To regulate the multiple biological mechanisms underlying restenosis, we focused on inhibition of an important transcription factor, nuclear factor-kappaB (NFκB), using a decoy strategy. METHODS AND RESULTS: For site-specific application of NFκB decoy oligodeoxynucleotides into target vessels during angioplasty, we developed a balloon catheter-based delivery system combined with biocompatible nanoparticles as oligodeoxynucleotides carriers. To clarify the therapeutic effect at the site of neointima, balloon angioplasty of the rabbit carotid arteries was performed at 4 weeks after initial endothelial denudation. This delivery system exhibited successful transfer of fluorescence-labeled nanospheres into the neointima in short-term contact with target vessels, and fluorescence could be detected ≥1 week after angioplasty. Consistently, local application of NFκB decoy oligodeoxynucleotides -loaded nanospheres resulted in significant inhibition of neointimal formation, associated with inhibition of NFκB binding activity in the injured arteries. The therapeutic effects were caused by inhibition of macrophage recruitment through the suppression of monocyte chemoattractant protein-1, vascular cell adhesion molecule-1, and CC chemokine ligand 4 expression and inhibition of vascular smooth muscle cell growth via a decrease in the expression of cyclin A and proliferating cell nuclear antigen. Importantly, application of NFκB nanospheres accelerated restoration of the endothelial cell monolayer, associated with enhanced expression of phosphorylated Bcl-2 in endothelial cells. CONCLUSIONS: A drug-coated balloon catheter using NFκB decoy oligodeoxynucleotides significantly inhibited the development of neointimal hyperplasia in rabbits. The present study indicates the possibility of a novel therapeutic option to prevent restenosis after angioplasty.

Oral nuclear factor-κB decoy oligonucleotides delivery system with chitosan modified poly(D,L-lactide-co-glycolide) nanospheres for inflammatory bowel disease.

Chitosan (CS)-modified poly(D,L-lactide-co-glycolide) (PLGA) nanospheres (NS) were developed and evaluated for use with a nuclear factor kappa B (NF-κB) decoy oligonucleotide (ODN) oral delivery system in an experimental model of ulcerative colitis (UC). Decoy ODN-loaded PLGA NS were prepared by an emulsion solvent diffusion method, and the physicochemical properties of NS were investigated. CS-modified PLGA NS (CS-PLGA NS) showed positive zeta potential, while unmodified PLGA NS (plain-PLGA NS) were negatively charged. Decoy ODN uptake studies with Caco-2 cells using confocal laser scanning microscopy (CLSM) indicated that CS-PLGA NS were more effectively taken up by the cells than plain-PLGA NS. Decoy ODN-loaded CS-PLGA NS were able to improve the stability of ODN against DNase I or an acidic medium, such as gastric juice. Daily oral administration of CS-PLGA NS in a rat model significantly improved dextran sulfate sodium-induced diarrhea, bloody feces, shortening of colon length, and myeloperoxidase activity. Furthermore, decoy ODN-loaded CS-PLGA NS were specifically deposited and adsorbed on the inflamed mucosal tissue of the UC model rat. These results suggested that CS-PLGA NS provide an effective means of colon-specific oral decoy ODN delivery in UC.

Particle size control of poly(dl-lactide-co-glycolide) nanospheres for sterile applications.

Parameters affecting the particle sizes of poly(DL-lactide-co-glycolide) (PLGA) nanospheres produced by the Emulsion Solvent Diffusion (ESD) method were evaluated in this study, so that suitable PLGA nanospheres could be prepared to pass through a membrane filter with 0.2 microm pore size and used as a sterile product. Experimental results demonstrated that the particle sizes of PLGA nanospheres could be reduced by the following efforts. (1) Increase stirring rate of poor solvent. (2) Decrease feed rate of good solvent. (3) Increase poor solvent ratio. (4) Increase the temperature of poor solvent. (5) Decrease polyvinyl alcohol concentration in poor solvent. (6) Increase ethanol concentration in good solvent. (7) Decrease PLGA concentration in good solvent. After optimization, PLGA nanospheres with a mean particle size of 102-163 nm and the 100-98% of filtration fraction could be produced and passed the bacteria challenge tests. This study found PLGA nanospheres can be efficiently prepared as a sterile product.

Histological examination of PLGA nanospheres for intratracheal drug administration.

Polylactide-glycolide (PLGA) nanospheres were reported as useful pulmonary drug delivery carriers for improving the pharmacological effect of drug. This paper describes the pathological and histological examinations of tissues after intratracheal instillation of drug encapsulated PLGA nanospheres. After intratracheally introducing FITC encapsulated PLGA nanospheres (dispersed in the 0.5 ml saline followed by mixing with an equal volume of air) to a rat, FITC was found existing in the rat's lungs, liver, kidney, brain, spleen and pancreas as demonstrated by immuno-histo-chemical staining with the dye. In this study, FITC stayed in alveoli at least for 1.5h after the intratracheal administration of the PLGA nanospheres, but the FITC almost disappeared 24h later. In addition, it was found that the PLGA nanospheres were absorbed in the blood immediately (within 0.25 h after the intratracheal administration) through the type 1 alveolar epithelium cell. Furthermore, the PLGA nanospheres were found resistant to uptake by macrophages such as alveolus macrophages and kupffer cells. The results showed that the possibility to induce tissue damage caused by the excessive immune response from the deposition of PLGA nanospheres was very low, because the nanospheres were not treated as foreign substances.

Evaluation of the permeability of hair growing ingredient encapsulated PLGA nanospheres to hair follicles and their hair growing effects.

This paper describes the process of encapsulating hair growing ingredients in the PLGA nanospheres by emulsion solvent diffusion method and investigates the feasibility of using the PLGA nanospheres as the DDS (Drug delivery System) carriers for delivering various hair growing ingredients to hair follicles. In-vitro and in-vivo tests were conducted to verify the performances of encapsulated PLGA nanospheres with three different hair growing ingredients. In the in-vitro tests, the scalp-pore permeability of hair growing ingredient encapsulated PLGA nanospheres (dispersed in the PBS solution) was examined using human scalp biopsies in a modified Bronaugh diffusion chamber in comparison to that of the control samples containing the hair growing ingredient in the PBS solution. Furthermore, the hair growing effect of the encapsulated PLGA nanospheres was evaluated with the C3H mice in the in-vivo tests. By observing the fluorescence intensity of the ingredients, as shown in the cross-section photographs of the human scalp biopsies, it was found that the dispersion liquids containing hair growing ingredient encapsulated PLGA nanospheres exerted a scalp-pore permeability 2.0- to 2.5-fold more marked than that of the control samples. Also, the hair growing activities were enhanced by using the encapsulated PLGA nanospheres, which transformed the hair growth cycle from the resting phase to the growing phase. As a result, the degree of hair growth was improved significantly. These results suggested that the PLGA nanosphere can be a new DDS carrier for delivering hair growing ingredients and drugs to the hair follicles.