Encapsulation Nanotechnology in Sperm Cryopreservation: Systems Preparation Methods and Antioxidants Enhanced Delivery.

Sperm cryopreservation promotes the storage and transport of germplasm for its use in artificial insemination (AI) and other advanced reproductive technologies. However, sperm cryopreservation causes several stresses including thermal shock, osmotic damage, and ice crystal formation, thereby reducing sperm quality. Supplementing cryoprotectant media with antioxidants has been reported to be positive in different species. It has been widely suggested to combine antioxidants with nanotechnology, to maximize therapeutic activity and to minimize undesirable side effects. In this review, we discuss the role of different antioxidants in sperm cryopreservation and their improved therapeutic effect through their formulation using nanotechnology. In addition, we report the different nano-systems preparation methods present in literature. Whilst the use of nanotechnology in animal production is still in its infancy, encouraging results from nutrition, biocidal, remedial, and reproductive studies are driving further investigations.

Development, validation and method stability study of a LC-MS method to quantify leuprolide (Hormone analog) in human plasma.

A rapid, highly sensitive and simple high-performance liquid chromatographic-tandem mass spectrometric (LC-MS) assay is developed and validated for the quantification of leuprolide: a Gonadotropin Releasing Hormone analog (GnRH) in human plasma. Moreover, various parameters of the method stability are determined. After the addition of stable isotope (internal standard), the leuprolide was extracted from human plasma by a C18 solid phase micro extraction (MEPS) cartridge and directly injected into LC-MS/MS system. Chromatographic separation was achieved using a Waters Atlantis HILIC, C18, 150 × 2.1 mm, 5 µ column. Mobile phase was a mixture of acetate buffer (pH 3) and acetonitrile (25/75). Drug detection was performed by MS using electrospray ionization in positive mode. Multiple reaction monitoring (MRM) with a tandem mass spectrometer was used to detect the analytes. Precursor to product ion transitions of: m/z 605.5 â†’ m/z 110.2 and m/z 609.1 â†’ m/z 249.1 were used to quantify leuprolide and leuprolide-13C6-15N, respectively. Sample analysis time was 3 min for each injection. The assay exhibited a linear dynamic range of 0.0500-40 ng/ml for each analyte with a lower limit of quantification (LLOQ) of: 0.0500 ng/ml. Furthermore, a complete analytic validation was carried out, including tests on: The specificity, precision, accuracy, matrix effect and stability under different storage conditions. Importantly, the obtained results established: an acceptable precision and accuracy for concentration over standard curve range. Nevertheless, it is to emphasize the simplicity, rapidity and also the high precision and accuracy of this novel LC-MS method, offering useful information about solution stability. Finally, this work is a good alternative to quantify Leuprolide concentration in human blood, especially on human clinic trials step.

NMR and ESR study of amphotericin B interactions with various binary phosphatidylcholine/phosphatidylglycerol membranes.

Several biologically relevant phospholipids are considered as potential excipients for IV administration liposome's formulation of AMB (Biopharmaceututics Classification System Class IV). On the basis of in vivo bioavaibility studies, DMPC and DMPG were ranked as the first potent encapsulation enhancers for this model drug, especially if one expects to target DMPG rich systems as pulmonary surfactant. Subsequently, dispersions (multilayers) of DMPC, DMPG or in binary systems with various molar ratios were prepared with or without AMB (molar ratios AMB/lipid) and further investigated using the 1H-,31P-NMR methods. It was found that equimolar preparations of DMPG/DMPG exhibited both a good encapsulation of AMB, while also probably able to target pulmonary surfactant. Besides DMPG did not exhibit the same solubilization properties. Conversely, no targeting by DMPC dispersion alone was expected, even if a good solubilization was obtained.

Fast dissolving cyclodextrin complex of piroxicam in solid dispersion part I: influence of ß-CD and HPß-CD on the dissolution rate of piroxicam.

Sublingual drug delivery is an interesting route for drug having significant hepatic first-pass metabolism or requiring rapid pharmacological effect as for patients suffering from swallowing difficulties, nausea or vomiting. Sublingual absorption could however be limited by the kinetic of drug dissolution. This study evaluated influences of cyclodextrins (ß-CD or HP-ß-CD) and their different inclusion process (spray-drying or freeze-drying) on the drug dissolution kinetic of solid dispersions in poly(ethylene glycol) (PEG, Mw 6000Da) of piroxicam, used as poor hydrosoluble drug model. A secondary objective was to determine influences of drug dispersion process in PEG (evaporation or melting methods) on the drug dissolution kinetic of piroxicam. Piroxicam solid dispersions containing or not cyclodextrins were characterized by different scanning calorimetry (DSC), Thermogravometry analyser (TGA) and Fourier transform-infrared spectroscopy (FT-IR) spectroscopy. In vitro drug dissolution study of these solid dispersions was then performed. The results demonstrated the high potential and interest of solid dispersions of drug previously included in cyclodextrins for sublingual delivery of hydrophobic drugs. This study also showed the advantages of evaporation method on the melting ones during drug dispersion in PEG. Indeed, drug complexation with cyclodextrins as dispersion by melting prevented the presence in solid dispersions of drug in crystalline form which can represent up to 63%. Moreover, dispersion in PEG by evaporation method gave more porous drug delivery system than with melting methods. This allowed complete (limited at most at 80-90% with melting methods) and quick drug dissolution without rebound effect like with melting ones.

Syndromic surveillance of acute gastroenteritis based on drug consumption.

Since 1998, the French Health Insurance (NHI) system had established a national database in order to reimburse drug prescriptions. These electronical data are a considerable potential source for syndromic surveillance because of their exhaustive and regular updates. The aim of this study was to develop a method to identify acute gastroenteritis (AG) cases from drug reimbursements of the NHI database. The algorithm aimed at discriminating AG from other pathologies was determined from a sample of 206 AG prescriptions and 351 non-AG prescriptions collected in five pharmacies. The AG case identification was mainly based on the lag time between the prescription and delivery day, the occurrence of non-AG case-specific drugs, AG case-specific drug associations and treatment duration. The discriminant algorithm led to a sensitive and specific indicator of medically treated cases of AG with a time-spatial resolution power which met the need for waterborne AG surveillance.