Genome-wide analysis highlights genetic dilution in Algerian sheep.

Algeria represents a reservoir of genetic diversity with local sheep breeds adapted to a large range of environments and showing specific features necessary to deal with harsh conditions. This remarkable diversity results from the traditional management of dryland by pastoralists over centuries. Most of these breeds are poorly productive, and the economic pressure leads farmers to realize anarchic cross-breeding (that is, not carried out in the framework of selection plans) with the hope to increase animal's conformation. In this study, eight of the nine local Algerian sheep breeds (D'men, Hamra, Ouled-Djellal, Rembi, Sidaoun, Tazegzawt, Berber and Barbarine) were investigated for the first time by genome-wide single-nucleotide polymorphism genotyping. At an international scale, Algerian sheep occupied an original position shaped by relations with African and European (particularly Italian) breeds. The strong genetic proximity with Caribbean and Brazilian breeds confirmed that the genetic make-up of these American breeds was largely influenced by the Atlantic slave trade. At a national scale, an alarming genetic dilution of the Berber (a primitive breed) and the Rembi was observed, as a consequence of uncontrolled mating practices with Ouled-Djellal. A similar, though less pronounced, phenomenon was also detected for the Barbarine, another ancestral breed. Genetic originality appeared to be better preserved in Tazegzawt, Hamra, D'men and Sidaoun. These breeds should be given high priority in the establishment of conservation plans to halt their progressive loss. For Berber and Barbarine that also occur in the bordering neighbor countries, urgent concerted transnational actions are needed.

Analysis of paraphenylenediamine.

The toxic Paraphenylenediamine is characterized by infrared spectrophotometry and nuclear magnetic resonance spectroscopy, whereas, high performance liquid chromatography with a refractive index detector was used to determine its purity in the suspect samples using external standardisation. An analytical method for determination of lower traces of paraphenylenediamine in post-mortem biological fluids was developed. This procedure involves deproteneization or hydrolysis followed by liquid-liquid extraction and derivatization with trifluoroacetic anhydride. 1 microL of the extract was then analysed by gas chromatography/iontrap mass spectrometry. Benzidine used as the internal standard for quantification and the extraction recovery test was evaluated to 85%. This method was validated in cases with paraphenylenediamine poisoning.

Cultivation of Cannabis sativa L. in northern Morocco.

Field studies on cannabis cultivation have provided socio-economic data relating to, inter alia, production, yield and income. But only laboratory analyses of cannabis plants can provide information on their chemical composition and their levels of psychoactive constituents, thus enabling them to be classed as a drug type or a fibre type. The present study, which covers cannabis in its fresh, dried and powdered forms, drew on fresh samples, obtained on the day they were harvested or immediately after preparation; that was done in order to prevent any alteration in the A-9-tetrahydrocannabinol (THC) caused by the oxidation that takes place as the product ages. The purpose of this study is to determine the THC level in 245 specimens obtained from 30 cannabis plots in three provinces of northern Morocco: Al Hoceima and Chefchaouen, where cannabis cultivation has a long tradition, and Larache, where cannabis cultivation has started only recently. Qualitative analysis using high performance liquid chromatography with diode array detection revealed the presence of both the acid and the decarboxylated form of the main cannabinoids, cannabidiol, THC and cannabinol, and gas chromatography/mass spectrometry was used for the characterization of minor cannibinoids. Quantitative analysis using gas chromatography coupled with mass spectrometry made it possible to determine the average delta-9-THC content of cannabis in its fresh form (0.5 per cent), its dry form (2.21 per cent) and its powdered form (8.3 per cent). The results show that the traditional areas of cannabis cultivation--Al Hoceima and Chefchaouen--produce cannabis with a higher delta-9-THC content than the Larache region. In addition, the present study establishes that male plants, often considered deficient in delta-9-THC, contain levels of the same order as those recorded for female plants, both in the leaves and in the tops.

Headspace-GC/MS detection of TATP traces in post-explosion debris.

In this study, we describe a HS-GC/MS method as a new analytical technique for the detection of triacetone triperoxide (TATP) traces in samples from post-explosion debris. We evaluate the optimum parameters for the analysis of this product with lowliness thermal decomposition and for the detection of TATP lesser than nanogram (.1 ng) level.

Optimization of an analytical method for detecting paraphenylenediamine (PPD) by GC/MS-iontrap in biological liquids.

A method for qualitative and quantitative determination of paraphenylenediamine in biological fluids (blood, urine and gastric content) was developed. This analytical procedure involves deproteneisation or hydrolysis, liquid-liquid extraction, derivatization with TFA followed by GC-MS iontrap analysis. Benzidine was the internal standard used for quantification and the extraction recovery test was about 85%. The detection limit of paraphenylenediamine was determined at 0.1 pg (S/N=10).