IN VITRO EFFECT OF ACETYLSALICYLIC ACID ON CALCIUM OXALATE CRYSTALLIZATION: AN APPROACH TO ANTILITHIASIS

Objective: In recent years, significant progress has been made in identifying and counting physico-chemical processes involved in urinary stone formation. The ability of urine to inhibit calcium oxalate crystallization is considered an important mechanism against stone formation. Several natural substances were tested to inhibit calcium oxalate crystallization. In the present study, we evaluate the effects of acetylsalicylic acid, also known as Aspirin, as an inhibitor of calcium oxalate crystallization in vitro.Methods: The nucleation and aggregation of calcium oxalate crystals were studied using turbidimetric 400-sec time course measurements of optic density at 620 nm after mixing solutions containing calcium chloride and sodium oxalate at room temperature, pH 5.7. The formation of crystals is induced by the addition of the oxalate to calcium solution. The effects on calcium oxalate crystal growth of acetylsalicylic acid with various concentrations were examined. The maximum increase of optic density in the course of time reflects maximum rate of formation of new particles. After reaching equilibrium, a progressive decrease of optic density with time is observed. Rate of aggregation is derived from the maximum decrease in optic density.Results: The results showed that if a concentration of acetylsalicylic acid is more than 1,66 mM both rate of formations of new particles and Rate of aggregation decreased (P<0.05).Conclusion: acetylsalicylic acid has a significant effect on nucleation as well as on crystal growth stage; consequently, it inhibits the crystal formation of calcium oxalate urinary lithiasis. Â

SOLUBILIZATION OF CELECOXIB USING ORGANIC COSOLVENT AND NONIONIC SURFACTANTS OPTIMIZED BY EXPERIMENTAL DESIGN

Objective: The solubility of drug substances in water is one of the major factors taken into account in the formulation of oral solutions and parenteral forms. The present study aims to evaluate the utility of a mixture design in improving water solubility of celecoxib through a micellar system by the use of organic co solvent and nonionic surfactants that are well tolerated by the parenteral route.Methods: In our study, a design of experiments approach was tested using a mixture design of nonionic surfactants (Tween® 80 and Solutol®HS 15), an organic cosolvent (ethanol) and celecoxib. Solubility determination was based on the analysis of samples absorbance at 215 nm. A particles size measurement was conducted using a Dynamic Light Scattering at the point showing the maximum of solubility.Results: The results showed a significant solubility increase in most of tested mixtures. The analysis of the design space showed that the solubility of celecoxib varies very closely with the concentration of Tween® 80 associated with ethanol and Solutol®HS 15 in water. Run 19 containing 0.8% of celecoxib, 10% of ethanol, 2% of Tween® 80, 2% of Solutol®HS 15 and water q. s. for 100% w/w improved celecoxib solubility by about 90 %, and showed an average particles size of 9.67 nm.Conclusion: Micellar solubilisation associating a cosolvent and nonionic surfactants seems to improve celecoxib solubility significantly. Mixture design provides maximum information about the effects and the proportions of each component from a limited number of experiments.Keywords: Solubility, Celecoxib, Mixture design, Cosolvent, SurfactantsÂ

REVIEW: FROM SCREENING TO APPLICATION OF MOROCCAN DYEING PLANTS: CHEMICAL GROUPS AND BOTANICAL DISTRIBUTION

Many dyes are contained in plants and are used for coloring a medium. They are characterized by their content of dyes molecules. They stimulate interest because they are part of a sustainable development approach. There are several chemicals families of plant dye which are contained in more than 450 plants known around the world. In this article, a study based on literature allowed us to realize an inventory of the main dyes plants potentially present in Morocco. A list of 117 plants was established specifying their botanical families, chemical Composition, Colors and parts of the plant used. Keywords: Natural dye, Morocco, Chemical structures, Plant pigments, Extractio

Assessment of non-destructive spectroscopy and chemometrics tools for the development of green analytical methods to determine the shelf-life of olive oils

The development of sustainable and environmentally friendly analytical methods for agri-food products and the modification of reference methods is an essential issue to be treated in green analytical chemistry. The potential application of non-destructive spectroscopic techniques with chemometrics tools to achieve these principles are examined in this work. In this study a new sustainable analytical approach based on the use of fluorescence spectroscopy and multivariate analysis methods of Machine-Learning(Support Vector Machine regression) and chemometrics (Partial Least Square regression) have been developed to control the quality of virgin olive oils in Morocco according to their shelf life. The spectral data of 45 samples were first analyzed by principal component analysis method (PCA), the PCA method shows an important classification of the three groups of olive oil according to their shelf life. The use of the regression methods SVM and PLS shows a high ability to predict the quality of olive oils, this ability is shown by the high value of R-square and the low value of root mean square error of calibration and crossvalidation (RMSEC, RMSECV), the validation of these models by cross-validation shows the potential of this sustainable analytical approach in the determination of the quality of virgin olive oils

Inventory of Toxic Plants in Morocco: An Overview of the Botanical, Biogeography, and Phytochemistry Studies

Since they are natural, plants are wrongly considered nondangerous; therefore people used them in various contexts. Each plant is used alone or in mixture with others, where knowledge and the requirements of preparation and consumption are not mastered. Thus, intoxications due to the use of plants have become more and more frequent. The reports of intoxications made at the Antipoison Center and Pharmacovigilance of Morocco (ACPM) support this finding, since the interrogations suffered by the victims show that the use of plants is practiced irrationally, anarchically, and uncontrollably. Faced by the increase of these cases of poisoning in Morocco, it seemed necessary to investigate the nature of poisonous plants, their monographs, and the chemicals responsible for this toxicity

Evaluation of the Capability of Horizontal ATR-FTMIR and UV-Visible Spectroscopy in the Discrimination of Virgin Olive Oils from the Moroccan Region of Beni Mellal-Khenifra

One of the most important challenges in the authentication of olive oil is the determination of the geographical origin of virgin olive oil. In this work, we evaluated the capacity of two spectroscopic techniques, UV-Visible and ATR-FTMIR, coupled with chemometric tools to determine the geographical origin of olive oils. These analytical approaches have been applied to samples that have been collected during the period of olive oil production, in the Moroccan region of Beni Mellal-Khenifra. To develop a rapid analysis tool capable of authenticating the geographical origin of virgin olive oils from five geographical areas of the Moroccan region of Beni Mellal-Khenifra, UV-Visible and ATR-FTMIR spectral data were processed by chemometric algorithms. PCA was applied on the spectral data set to represent the data in a very small space, and then discrimination methods were applied on the principal components synthesized by the PCA. The application of the PCA-LDA method on the spectral data of UV-Visible and ATR-FTMIR shows a good ability to classify olive oils according to their geographical origin with a percentage of correct classification that represents 90.24% and 85.87%, respectively, and the processing of the spectral data of UV-Visible and ATR-FTMIR by PCA-SVM allows differentiating correctly between five olive oils with a correct classification rate of 100% and 97.56, respectively. This study demonstrated the feasibility of UV-Visible and ATR-FTMIR fingerprinting (routine technique) for the geographical classification of olive oils in the Moroccan region of Beni Mellal-Khenifra. Such developed methods can be proposed as alternative and complementary methods to authenticate the geographical origin of virgin olive oil

Bioequivalence regulation in emerging countries: Example of Moroccan regulations on immediate release formulations and comparison with international guidelines

International audienceThe purpose of this study was to analyze Moroccan regulations on bioequivalence studies and compare them with some international guidelines. It emerged that, as most common guidelines, Moroccan regulations treated essential questions relating to the conduct of bioequivalence studies while remaining general. An effort to harmonize the Moroccan regulations as closely as possible with international guidelines such as European Medicines Agency and World Health Organization was made. The decree 2-12-198 on bioequivalence studies includes worldwide gold standards such as inclusion and exclusion criteria, study design, choice and number of subjects, conduct of the study, pharmacokinetic parameters, BE acceptance criteria, and biowaiver requirements. It specifically addresses issues such as pro-drug, metabolites, urinary samples, and endogenous substances. Specific precisions such as the case of the modified release forms, the replacement of subjects on the withdrawal, or drop-out of a volunteer are not covered by this general decree and should be part of new directives, in the future. For an emerging country, the integration of Biopharmaceutics Classification System biowaivers within the decree confirms the efforts being made by the Moroccan regulations to join the most advanced guidelines on the investigation of bioequivalence and to prepare the International Council on Harmonisation M9 adoption

Development of Fast Analytical Method for the Detection and Quantification of Honey Adulteration Using Vibrational Spectroscopy and Chemometrics Tools

In this study, the Fourier transform mid-infrared (FT-MIR) spectroscopy technique combined with chemometrics methods was used to monitor adulteration of honey with sugar syrup. Spectral data were recorded from a wavenumber region of 4000–600 cm−1, with a spectral resolution of 4 cm−1. Principal component analysis (PCA) and hierarchical cluster analysis (HCA) were used for qualitative analysis to discriminate between adulterated and nonadulterated honey. For quantitative analysis, we used partial least-squares regression (PLS-R) and the support vector machine (SVM) to develop optimal calibration models. The use of PCA shows that the first two principal components account for 96% of the total variability. PCA and HCA allow classifying the dataset into two groups: adulterated and unadulterated honey. The use of the PLS-R and SVM-R calibration models for the quantification of adulteration shows high-performance capabilities represented by a high value of correlation coefficients R2 greater than 98% and 95% with lower values of root mean square error (RMSE) less than 1.12 and 1.85 using PLS-R and SVM-R, respectively. Our results indicate that FT-MIR spectroscopy combined with chemometrics techniques can be used successfully as a simple, rapid, and nondestructive method for the quantification and discrimination of adulterated honey

Knowledge, attitudes and practices of the liberal doctors in relation to the national convention signed in the framework of Mandatory Health Insurance in Morocco: a cross-sectional study

Introduction: under the Mandatory Health Insurance (MHI) scheme, liberal doctors signed their first national convention in the year of 2006. The delay in renewing this agreement could negatively affect the accessibility of the insured persons to medical care. The objective of this study was to explore the knowledge, attitude and practice of the liberal doctors towards their adherence to the national convention signed under MHI scheme and to propose some improvements. Methods: our study is cross-sectional based on a descriptive survey targeting the population of liberal doctors adhering to the signed convention under the MHI in Morocco. The material used was a questionnaire that was administered to doctors selected. The processing and analyzing of results were performed with SPSS 13.0. Results: the study, conducted in 2016, examines included 40 liberal doctors. 97.5% of them reported dissatisfaction with the National Reference Pricing. 60% of the them were demotivated to the application of the national convention because of the lack in educational materials. There was no significant difference in the attitudes between general practitioners and specialists, all of whom considered that remuneration was unfair under MHI (p = 0.689), they also considered that working conditions have deteriorated (p = 0.256). Conclusion: the behavior of liberal doctors towards the national convention signed within the framework of the MHI hides a general dissatisfaction whatever the place of practice. This dissatisfaction was felt by physicians regardless of their seniority or specialty. Several efforts should be made to find a compromise between doctors and the health insurance system to improve patient access to care

The development of green analytical methods to monitor adulteration in honey by UV-visible spectroscopy and chemometrics models

The development of green and environmentally friendly analytical methods for agri-food products is an essential element to be treated by green analytical chemistry. In this study, UV-Visible spectroscopy, combined with a mathematical and statistical or chemometrics algorithm, has been developed to monitor honey quality. Partial Least Squares Regression (PLS-R) and Support Vector Machine Learning Regression (SVM-R) showed an adequate quantification of the percentage of impurity. The use of these models demonstrates a high ability to predict the quality of honey. R-square’s high value shows this ability, and the low value of root mean square error of calibration and cross-validation (RMSECV, RMSEC). The results indicate that UV-Visible spectroscopy allied with the Chemometrics algorithms can provide a quick, non-destructive, green, and reliable method to control the quality and predict honey’s adulteration level