Oligonucleotide Solid Nucleolipid Nanoparticles against Antibiotic Resistance of ESBL-Producing Bacteria

Antibiotic resistance has become a major issue in the global healthcare system, notably in the case of Gram-negative bacteria. Recent advances in technology with oligonucleotides have an enormous potential for tackling this problem, providing their efficient intrabacterial delivery. The current work aimed to apply this strategy by using a novel nanoformulation consisting of DOTAU, a nucleolipid carrier, in an attempt to simultaneously deliver antibiotic and anti-resistance oligonucleotides. Ceftriaxone, a third-generation cephalosporin, was formulated with DOTAU to form an ion pair, and was then nanoprecipitated. The obtained solid nanocapsules were characterized using FT-IR, XRD, HPLC, TEM and DLS techniques and further functionalized by the anti-resistance ONα sequence. To obtain an optimal anti-resistance activity and encapsulation yield, both the formulation protocol and the concentration of ONα were optimized. As a result, monodispersed negatively charged nanoparticles of CFX–DOTAU-ONα with a molar ratio of 10:24:1 were obtained. The minimum inhibitory concentration of these nanoparticles on the resistant Escherichia coli strain was significantly reduced (by 75%) in comparison with that of non-vectorized ONα. All aforementioned results reveal that our nanoformulation can be considered as an efficient and relevant strategy for oligonucleotide intrabacterial delivery in the fight against antibiotic resistance.

Nucleotide lipid-based hydrogel as a new biomaterial ink for biofabrication

One of the greatest challenges in the field of biofabrication remains the discovery of suitable bioinks that satisfy physicochemical and biological requirements. Despite recent advances in tissue engineering and biofabrication, progress has been limited to the development of technologies using polymer-based materials. Here, we show that a nucleotide lipid-based hydrogel resulting from the self-assembly of nucleotide lipids can be used as a bioink for soft tissue reconstruction using injection or extrusion-based systems. To the best of our knowledge, the use of a low molecular weight hydrogel as an alternative to polymeric bioinks is a novel concept in biofabrication and 3D bioprinting. Rheological studies revealed that nucleotide lipid-based hydrogels exhibit suitable mechanical properties for biofabrication and 3D bioprinting, including i) fast gelation kinetics in a cell culture medium and ii) shear moduli and thixotropy compatible with extruded oral cell survival (human gingival fibroblasts and stem cells from the apical papilla). This polymer-free soft material is a promising candidate for a new bioink design.

Lipid oligonucleotides as a new strategy for tackling the antibiotic resistance

Antibiotic resistance has become a major issue in public health especially for one of the most used antibiotics; the third-generation cephalosporins. One of the main resistance mechanisms in Enterobacteriaceae, is the production of Extended-Spectrum β-lactamases. Here, we demonstrated that the oligonucleotide therapy is an efficient approach to reduce the resistance of bacteria to antibiotic treatment. Lipid oligonucleotides (LONs) were proved to be efficient strategies in both delivering the oligonucleotide sequences in the prokaryotic cells and decreasing the Minimum Inhibitory Concentration of resistant bacteria to a third generation cephalosporin, the ceftriaxone. Accordingly, we demonstrated the strong antimicrobial potential of this LON strategy targeting the ß-lactamase activity on both clinical and laboratory strains. Our results support the concept that the self-delivery of oligonucleotide sequences via lipid conjugation may be extended to other antimicrobial drugs, which opens novel ways to struggle against the antibiotic resistance.

Development of Rectodispersible Tablets and Granulate Capsules for the Treatment of Serious Neonatal Sepsis in Developing Countries

Current pediatric antibiotic therapies often use oral and parenteral routes of administration. Neither are suitable for treating very sick neonates who cannot take oral medication and may be several hours away from hospital in developing countries. Here, we report on the development of rectal forms of ceftriaxone, a third-generation cephalosporin. Rectodispersible tablets and capsules were developed and successfully passed 6-month accelerated stability tests. Rabbit bioavailability showed plasma concentrations above the minimal inhibitory concentrations for 3 formulations of rectodispersible tablets and 2 formulations of hard capsules. Clinical batches are currently being prepared for human evaluation with the prospect of offering therapeutic alternatives for treating critically ill neonates. This proof of concept for efficient rectal delivery of antibiotics could help the development of other rectal antibiotic treatments and increase options for noninvasive drug development for pediatric patients.

Data on iron oxide core oil-in-water nanoemulsions for atherosclerosis imaging

The data presented in this article are related to the publication entitled "Iron oxide core oil-in-water nanoemulsion as tracer for atherosclerosis MPI and MRI imaging" (Prévot et al., 2017) [1]. Herein we describe the synthesis and the characteristics of the Superparamagnetic Iron Oxide Nanoparticles (SPION) loaded inside nanoemulsions (NEs). Focus was set on obtaining SPION with narrow size distribution and close to superparamagnetic limit (20 nm) in order to reach a reasonable magnetic signal. Nanoparticles (NPs) of three different sizes were obtained (7, 11 and 18 nm) and characterized using transmission electron microscopy (TEM), X-ray diffraction (XRD), vibrating sample magnetometer (VSM), diffuse reflectance infrared Fourier transform (DRIFT) and thermogravimetric analysis (TGA). SPION were coated with oleic acid (OA) in order to load them inside the oily core of NEs droplets. SPION loaded NEs were magnetically sorted using MACS® MS Column (Miltenyi Biotec) and iron quantification was performed by UV-spectrometry measurements.

Iron oxide core oil-in-water nanoemulsion as tracer for atherosclerosis MPI and MRI imaging

PURPOSE

For early atherosclerosis imaging, magnetic oil-in-water nanoemulsion (NE) decorated with atheroma specific monoclonal antibody was designed for Magnetic Particle Imaging (MPI) and Magnetic Resonance Imaging (MRI). MPI is an emerging technique based on direct mapping of superparamagnetic nanoparticles which may advantageously complement MRI.

METHODS

NE oily droplets were loaded with superparamagnetic iron oxide nanoparticles of 7, 11 and 18nm and biofunctionalized with atheroma specific scFv-Fc TEG4-2C antibody.

RESULTS

Inclusion of nanoparticles inside NE did not change the hydrodynamic diameter of the oil droplets, close to 180nm, nor the polydispersity. The droplets were negatively charged (ζ=-30mV). In vitro MPI signal was assessed by Magnetic Particle Spectroscopy (MPS). NE displayed MRI and MPS signals confirming its potential as new contrast agent. NE MPS signal increase with NPs size close to the gold standard (Resovist). In MRI, NE displayed R₂* transversal relaxivity of 45.45, 96.04 and 218.81mM^-1s^-1 for 7, 11 and 18nm respectively. NE selectively bind atheroma plaque both in vitro and ex vivo in animal models of atherosclerosis.

CONCLUSION

Magnetic NE showed reasonable MRI/MPS signals and a significant labelling of the atheroma plaque. These preliminary results support that NE platform could selectively image atherosclerosis.

Solid Lipid Nanoparticles for Image-Guided Therapy of Atherosclerosis

Although the application of nanotechnologies to atherosclerosis remains a young field, novel strategies are needed to address this public health issue. In this context, the magnetic resonance imaging (MRI) approach has been gradually investigated in order to enable image-guided treatments. In this contribution, we report a new approach based on nucleoside-lipids allowing the synthesis of solid lipid nanoparticles (SLN) loaded with iron oxide particles and therapeutic agents. The insertion of nucleoside-lipids allows the formation of stable SLNs loaded with prostacycline (PGI2) able to inhibit platelet aggregation. The new SLNs feature better relaxivity properties in comparison to the clinically used contrast agent Feridex, indicating that SLNs are suitable for image-guided therapy.

Preliminary pharmaceutical development of antimalarial-antibiotic cotherapy as a pre-referral paediatric treatment of fever in malaria endemic areas

Artemether (AM) plus azithromycin (AZ) rectal co-formulations were studied to provide pre-referral treatment for children with severe febrile illnesses in malaria-endemic areas. The target profile required that such product should be cheap, easy to administer by non-medically qualified persons, rapidly effective against both malaria and bacterial infections. Analytical and pharmacotechnical development, followed by in vitro and in vivo evaluation, were conducted for various AMAZ coformulations. Of the formulations tested, stability was highest for dry solid forms and bioavailability for hard gelatin capsules; AM release from AMAZ rectodispersible tablet was suboptimal due to a modification of its micro-crystalline structure.

Screening paediatric rectal forms of azithromycin as an alternative to oral or injectable treatment

The aim of this study was to identify a candidate formulation for further development of a home or near-home administrable paediatric rectal form of a broad-spectrum antibiotic - specially intended for (emergency) use in tropical rural settings, in particular for children who cannot take medications orally and far from health facilities where injectable treatments can be given. Azithromycin, a broad-spectrum macrolide used orally or intravenously for the treatment of respiratory tract, skin and soft tissue infections, was selected because of its pharmacokinetic and therapeutic properties. Azithromycin in vitro solubility and stability in physiologically relevant conditions were studied. Various pharmaceutical forms, i.e. rectal suspension, two different rectal gels, polyethylene glycol (PEG) suppository and hard gelatin capsule (HGC) were assessed for in vitro dissolution and in vivo bioavailability in the rabbit. Azithromycin PEG suppository appears to be a promising candidate.

Development of NIRS method for quality control of drug combination artesunate-azithromycin for the treatment of severe malaria

Near infrared spectroscopy (NIRS) methods were developed for the determination of analytical content of an antimalarial-antibiotic (artesunate and azithromycin) co-formulation in hard gelatin capsule (HGC). The NIRS consists of pre-processing treatment of spectra (raw spectra and first-derivation of two spectral zones), a unique principal component analysis model to ensure the specificity and then two partial least-squares regression models for the determination content of each active pharmaceutical ingredient. The NIRS methods were developed and validated with no reference method, since the manufacturing process of HGC is basically mixed excipients with active pharmaceutical ingredients. The accuracy profiles showed β-expectation tolerance limits within the acceptance limits (±5%). The analytical control approach performed by reversed phase (HPLC) required two different methods involving two different preparation and chromatographic methods. NIRS offers advantages in terms of lower costs of equipment and procedures, time saving, environmentally friendly.

The initial pharmaceutical development of an artesunate/amodiaquine oral formulation for the treatment of malaria: a public-private partnership

Background

Artemisinin-based combination therapy is currently recommended worldwide for the treatment of uncomplicated malaria. Fixed-dose combinations are preferred as they favour compliance. This paper reports on the initial phases of the pharmaceutical development of an artesunate-amodiaquine (ASAQ) bilayer co-formulation tablet, undertaken following pre-formulation studies by a network of scientists and industrials from institutions of both industrialized and low income countries.

Methods

Pharmaceutical development was performed by a research laboratory at the University Bordeaux Segalen, School of Pharmacy, for feasibility and early stability studies of various drug formulations, further transferred to a company specialized in pharmaceutical development, and then provided to another company for clinical batch manufacturing. The work was conducted by a regional public-private not-for-profit network (TropiVal) within a larger Public Private partnership (the FACT project), set up by WHO/TDR, Médecins Sans Frontières and the Drugs for Neglected Disease initiative (DNDi).

Results

The main pharmaceutical goal was to combine in a solid oral form two incompatible active principles while preventing artesunate degradation under tropical conditions. Several options were attempted and failed to provide satisfactory stability results: incorporating artesunate in the external phase of the tablets, adding a pH regulator, alcoholic wet granulation, dry granulation, addition of an hydrophobic agent, tablet manufacturing in controlled conditions. However, long-term stability could be achieved, in experimental batches under GMP conditions, by physical separation of artesunate and amodiaquine in a bilayer co-formulation tablet in alu-alu blisters. Conduction of the workplan was monitored by DNDi.

Conclusions

Collaborations between research and industrial groups greatly accelerated the process of development of the bi-layered ASAQ tablet. Lack of public funding was the main obstacle hampering the development process, and no intellectual property right was claimed. This approach resulted in a rapid technology transfer to the drug company Sanofi-Aventis, finalizing the process of development, registration and WHO pre-qualification of the fixed-dose co-formulation together with DNDi. The bi-layered tablet is made available under the names of Coarsucam^® and Artesunate amodiaquine Winthrop^®, Sanofi-Aventis. The issue related to the difficulty of public institutions to valorise their participation in such initiative by lack of priority and funding of applied research is discussed.

Fixed artesunate-amodiaquine combined pre-formulation study for the treatment of malaria

Artemisinin-based combination therapies, including artesunate (AS) + amodiaquine (AQ), are the currently recommended first-line treatment of uncomplicated falciparum malaria. Fixed-dose co-formulations offer logistic and adherence advantages. This paper reports the initial research phase of the pre-development process of an AS-AQ formulation, further developed by the Drug for Neglected Diseases Initiative (DNDi). Results demonstrate that AS and AQ are not compatible, and AS degradation is related to three main parameters: water content (>1%), elevated temperature (80 degrees C in dry condition) and possibly the 4-aminoquinoline moiety. Furthermore, AS and AQ incompatibility led to AS degradation and pharmaco-technical changes in classical wet granulation tablets. Both active principles are stable as dry powders. These investigations led to further development of various co-formulations, including the bilayer tablet currently on the market.

Fixed artesunate-amodiaquine combined pre-formulation study for the treatment of malaria

Artemisinin-based combination therapies, including artesunate (AS)+amodiaquine (AQ), are the currently recommended first-line treatment of uncomplicated falciparum malaria. Fixed-dose co-formulations offer logistic and adherence advantages. This paper reports the initial research phase of the pre-development process of an AS-AQ formulation, further developed by the Drug for Neglected Diseases Initiative (DNDi). Results demonstrate that AS and AQ are not compatible, and AS degradation is related to three main parameters: water content (>1%), elevated temperature (80 degrees C in dry condition) and possibly the 4-aminoquinoline moiety. Furthermore, AS and AQ incompatibility led to AS degradation and pharmaco-technical changes in classical wet granulation tablets. Both active principles are stable as dry powders. These investigations led to further development of various co-formulations, including the bilayer tablet currently on the market.

Molecular blocking of CD23 supports its role in the pathogenesis of arthritis

Background

CD23 is a differentiation/activation antigen expressed by a variety of hematopoietic and epithelial cells. It can also be detected in soluble forms in biological fluids. Initially known as the low-affinity receptor for immunoglobulin E (FcεRII), CD23 displays various other physiologic ligands such as CD21, CD11b/c, CD47-vitronectin, and mannose-containing proteins. CD23 mediates numerous immune responses by enhancing IgE-specific antigen presentation, regulating IgE synthesis, influencing cell differentiation and growth of both B- and T-cells. CD23-crosslinking promotes the secretion of pro-inflammatory mediators from human monocytes/macrophages, eosinophils and epithelial cells. Increased CD23 expression is found in patients during allergic reactions and rheumatoid arthritis while its physiopathologic role in these diseases remains to be clarified.

Methodology/Principal Findings

We previously generated heptapeptidic countrestructures of human CD23. Based on in vitro studies on healthy and arthritic patients' cells, we showed that CD23-specific peptide addition to human macrophages greatly diminished the transcription of genes encoding inflammatory cytokines. This was also confirmed by significant reduction of mediator levels in cell supernatants. We also show that CD23 peptide decreased IgE-mediated activation of both human and rat CD23⁺ macrophages. In vivo studies in rat model of arthritis showed that CD23-blocking peptide ameliorates clinical scores and prevent bone destruction in a dose dependent manner. Ex-vivo analysis of rat macrophages further confirmed the inhibitory effect of peptides on their activation. Taken together our results support the role of CD23 activation and subsequent inflammatory response in arthritis.

Conclusion

CD23-blocking peptide (p30A) prevents the activation of monocytes/macrophages without cell toxicity. Thus, targeting CD23 by antagonistic peptide decreases inflammatory markers and may have clinical value in the treatment of human arthritis and allergic reactions involving CD23.

Rutoside decreases human macrophage-derived inflammatory mediators and improves clinical signs in adjuvant-induced arthritis

Background

Dietary flavonols may play an important role in the adjunct therapy of chronic inflammation. The availability of therapeutic formulations of pentahydroxyflavone glycoside, rutoside (RU), led us to investigate the ability of this molecule to modulate the release of various proinflammatory mediators from human activated macrophages in vitro and to ameliorate arthritic markers in a rat model.

Methods

RU was added simultaneously to human macrophages during their activation. Cells were then analyzed for inflammation-related gene expression using a specific array, and cell supernatants were collected to measure inflammatory mediators. RU was also injected into adjuvant-induced arthritic rats, and disease progression and body weight were evaluated until 50 days after injection. Sera and peritoneal macrophages were also collected to quantify the RU effect on various inflammatory markers.

Results

RU inhibited inflammation-related gene expression in activated human macrophages and the release of nitric oxide, tumor necrosis factor-alpha, interleukin (IL)-1, and IL-6 from these cells. In a rat model, RU inhibited clinical signs of chronic arthritis, correlating with decreased levels of inflammatory cytokines detected in rat sera and macrophage supernatants.

Conclusion

Thus, RU may have clinical value in reducing inflammatory manifestations in human arthritis and other inflammatory diseases.

Therapeutic and preventive properties of quercetin in experimental arthritis correlate with decreased macrophage inflammatory mediators

Pentahydroxyflavone dihydrate, quercetin (QU) is one of common flavonols biosynthesized by plants and has been suggested to modulate inflammatory responses in various models. In the present study, we investigated in vivo effects of oral or intra-cutaneous QU in chronic rat adjuvant-induced arthritis (AA). Growth delay and arthritic scores were evaluated daily after AA induction in Lewis rats. Oral administration of QU (5 x 160 mg/kg) to arthritic rats resulted in a clear decrease of clinical signs compared to untreated controls. Intra-cutaneous injections of lower doses (5 x 60 mg/kg) of QU gave similar anti-arthritic effects, while 5 x 30 mg/kg concentrations were inefficient in this respect. Finally, injection of relatively low QU doses (5 x 30 mg/kg) prior to AA induction significantly reduced arthritis signs. As QU was suggested to inhibit macrophage-derived cytokines and nitric oxide (NO), we then analyzed macrophage response ex vivo. Anti-arthritic effects of QU correlated with significant decrease of inflammatory mediators produced by peritoneal macrophages, ex vivo and in vitro. These data indicate that QU is a potential anti-inflammatory therapeutic and preventive agent targeting the inflammatory response of macrophages.

[Interprofessional cooperation in home care of disabled elderly patients. Results of a model project]

As is well known from experience, physicians, nurses, and other not-medical professions in ambulant care for elder people generally do not co-operate intensively, although there are many points of contact. With regard to this situation and the growth of the group of very old people, which request the further development of geriatric medicine and rehabilitation, a research project was realized in order to build up, improve and, as far as necessary, systematize inter-professional co-operation; this process was evaluated referring to the conditions and the effects of more intensive co-operation. This project led to several agreements concerning the improvement of co-operation; especially there are indications that the elder people in question are better cared for on the basis of intensive inter-professional co-operation and that avoidable expenses can be saved.