Spray-drying of inhalable, multifunctional formulations for the treatment of biofilms formed in cystic fibrosis.

Cystic fibrosis (CF) is a serious lung disease, commonly susceptible to Pseudomonas aeruginosa colonization. The dense mucus together with biofilm formation limit drug permeability and prevent the drug from reaching the site of action, causing treatment failure of the bacterial infection. Besides the use of antibiotics, the mucolytic agent N-acetylcysteine (NAC) is recommended to be co-administered in the treatment of CF. Although several formulations have been developed for inhalation therapy to improve the pulmonary condition in CF patients, there is still no comprehensive study on a combined multifunctional dry powder formulation of antibiotics with NAC. In this work, we developed an innovative multifunctional dry powder inhaler (DPI) formulation based on salt formation between NAC and antibiotics and characterized their solid state properties and physical stability. NAC could be spray dried together with three different antibiotics, azithromycin (Azi), tobramycin (Tobra) and ciprofloxacin (Cipro), without the use of organic solvents to form Azi/NAC, Tobra/NAC and Cipro/NAC DPI formulations. Solid-state characterization of these DPI formulations showed that they were amorphous after spray drying. Azi/NAC and Tobra/NAC form co-amorphous salt systems that were physically stable under storage at stress conditions. For particle characterization, the obtained mass median aerodynamic diameters were in a suitable range for inhalation (< 5.0µm). The multifunctional antibiotic/NAC formulations conserved or improved the antibiotic susceptibility and showed promising results regarding the inhibition of P. aeruginosa PA14 biofilm formation.

Ciprofloxacin-loaded PLGA nanoparticles against cystic fibrosis P. aeruginosa lung infections.

Current pulmonary treatments against Pseudomonas aeruginosa infections in cystic fibrosis (CF) lung suffer from deactivation of the drug and immobilization in thick and viscous biofilm/mucus blend, along with the general antibiotic resistance. Administration of nanoparticles (NPs) with high antibiotic load capable of penetrating the tight mesh of biofilm/mucus can be an advent to overcome the treatment bottlenecks. Biodegradable and biocompatible polymer nanoparticles efficiently loaded with ciprofloxacin complex offer a solution for emerging treatment strategies. NPs were prepared under controlled conditions by utilizing MicroJet Reactor (MJR) to yield a particle size of 190.4±28.6nm with 0.089 PDI. Encapsulation efficiency of the drug was 79% resulting in a loading of 14%. Release was determined to be controlled and medium-independent in PBS, PBS+0.2% Tween 80 and simulated lung fluid. Cytotoxicity assays with Calu-3 cells and CF bronchial epithelial cells (CFBE41o-) indicated that complex-loaded PLGA NPs were non-toxic at concentrations ≫ MICcipro against lab strains of the bacteria. Antibacterial activity tests revealed enhanced activity when applied as nanoparticles. NPs' colloidal stability in mucus was proven. Notably, a decrease in mucus turbidity was observed upon incubation with NPs. Herewith, ciprofloxacin complex-loaded PLGA NPs are introduced as promising pulmonary nano drug delivery systems against P.aeruginosa infections in CF lung.

Diagnostic value of the neutrophil myeloperoxidase index in horses with systemic inflammation.

The myeloperoxidase index (MPXI) was investigated as a diagnostic indicator of systemic inflammation in a retrospective study using data from 859 hospitalised horses. A reference interval of 8.5-10.4 for the MPXI was established. In horses with systemic inflammatory response syndrome (SIRS), the MPXI was significantly lower than in healthy horses, those with localised inflammation and those with sepsis. The MPXI in horses with sepsis was also significantly lower than in healthy animals and those with localised inflammation. Horses in the SIRS group with leucopenia, white blood cell (WBC) count within the reference interval (WRI) or leucocytosis had significantly lower MPXIs than healthy horses, those with localised inflammation and those with sepsis in the same WBC count subgroups. In horses with sepsis and WBC count WRI, the MPXI was significantly lower than in healthy horses or those with localised inflammation. MPXI is a useful complementary tool to identify horses with systemic inflammation, especially if they have WBC counts WRI.

Keratoconjunctivitis sicca attributable to parasympathetic facial nerve dysfunction associated with hypothyroidism in a horse.

CASE DESCRIPTION: A 6-year-old 680-kg (1,496-lb) German Warmblood gelding was evaluated because of bilateral blepharospasm and head shaking. CLINICAL FINDINGS: Moderate blepharospasm was evident bilaterally, and both eyes had hyperemic and edematous conjunctivas and lusterless corneas. For each eye, the Schirmer tear test value was only 7 mm/min. The horse's nasal mucosa was dry. Abnormal behaviors included mild repetitive vertical movement of the head, snorting, and flehmen response (classic signs of head shaking). Touching the horse's nostrils and face revealed paresthesia and dysesthesia with slight nasolabial muscle hypertrophy bilaterally. Cranial nerve examination revealed no other abnormalities. Serum thyroxine concentration was low, and results of thyrotropin-releasing hormone and thyroid-stimulating hormone stimulation tests were negative, indicating that the horse had hypothyroidism. The diagnoses included keratoconjunctivitis sicca and dry nares attributable to parasympathetic facial nerve dysfunction, head-shaking syndrome with paresthesia and dysesthesia of the face attributable to sensory trigeminal nerve disorder, and hypothyroidism. The 2 nerve dysfunctions were considered peripheral neuropathies that were most likely caused by hypothyroidism. TREATMENT AND OUTCOME: Treatment of both eyes was initiated with topical applications of cyclosporine, 0.5% sodium hyaluronate, and vitamin A ointment. Levothyroxine (20 microg/kg [9.1 microg/lb], PO, q 24 h) was administered. Within 3 weeks to 4 months, serum thyroxine concentration was within reference range, and clinical signs and Schirmer tear test values improved. CLINICAL RELEVANCE: Hypothyroidism should be considered as a differential diagnosis in horses with peripheral neuropathy or keratoconjunctivitis sicca. In affected horses, administration of levothyroxine may lead to resolution of neurologic signs.