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hosted in a folded and low to medium grade sedimentary and volcanic rocks, unconformably overlaid by Permo-Triassic to Cretaceous red beds and limestones. Intrusion of the hydrothermally altered multiphase ca. similar to 330-319 Ma Aouli granite batholith has contact metamorphosed the host rocks to a metamorphic assemblage of cordierite, andalusite, chlorite, muscovite, and biotite +/- sillimanite +/- garnet. The mineralized structures that consist mostly of quartz, fluorite, and barite occur principally as ENE-WSW, WNW-ESE, and E-W-trending trans-tensional steeply dipping veins, veinlets and en echelon tension gash fillings. Irrespective of colour, location, paragenesis and textural position within the mineralized vein structure, the fluorite is characterized by high total REY contents ranging from 250 to 662 ppm, distinctive positive Eu and Y anomalies, and middle rare-earth element enrichment. Fluid inclusion data indicate that the ore-forming fluids correspond to evolved NaCl-CaCl2 + other cations sedimentary (94-174 degrees C), saline (14-24 wt% NaCl equiv.) brines. The strontium isotopic compositions of fluorite (Sr-87/Sr-86 = 0.710155-0.712293) and barite (0.710215-0.701401), along with the Liassic dolomitized limestones (0.707867-0.708140) are more radiogenic than the Cambro-Ordovician and Triassic-Early Jurassic seawater values, with the Aouli Late Variscan granite (0.70814 +/- 12) and the Triassic arkoses (0.709839-0.712313) displaying the highest Sr-87/Sr-86 ratios. Barite separates show uniform delta S-34 ratios of +11% to +13.4% consistent with Permian-Triassic seawater sulphate. The calculated REY fluid compositions along with fluid inclusion, strontium and sulphur isotope data point to the role of hot sedimentary brines with fluid-rock interaction at high fluid/rock ratios. The fluid system is likely related to the Pangea rifting and subsequent Central Atlantic opening during Permian-Triassic time. The fluorite-barite mineralization is likely due to mixing at the basement-cover interface of an ascending deep-seated fluid that equilibrated with Variscan crystalline basement rocks and cooler more dilute formation water. (C) 2015 Published by Elsevier Ltd.

Relevant for various areas of human genetics, Y-chromosomal short tandem repeats (Y-STRs) are commonly used for testing close paternal relationships among individuals and populations, and for male lineage identification. However, even the widely used 17-loci Yfiler set cannot resolve individuals and populations completely. Here, 52 centers generated quality-controlled data of 13 rapidly mutating (RM) Y-STRs in 14,644 related and unrelated males from 111 worldwide populations. Strikingly, >99% of the 12,272 unrelated males were completely individualized. Haplotype diversity was extremely high (global: 0.9999985, regional: 0.99836–0.9999988). Haplotype sharing between populations was almost absent except for six (0.05%) of the 12,156 haplotypes. Haplotype sharing within populations was generally rare (0.8% nonunique haplotypes), significantly lower in urban (0.9%) than rural (2.1%) and highest in endogamous groups (14.3%). Analysis of molecular variance revealed 99.98% of variation within populations, 0.018% among populations within groups, and 0.002% among groups. Of the 2,372 newly and 156 previously typed male relative pairs, 29% were differentiated including 27% of the 2,378 father–son pairs. Relative to Yfiler, haplotype diversity was increased in 86% of the populations tested and overall male relative differentiation was raised by 23.5%. Our study demonstrates the value of RMY-STRs in identifying and separating unrelated and related males and provides a reference database. ispartof: Human Mutation vol:35 issue:8 pages:1021-1032 status: published

Relevant for various areas of human genetics, Y-chromosomal short tandem repeats (Y-STRs) are commonly used for testing close paternal relationships among individuals and populations, and for male lineage identification. However, even the widely used 17-loci Yfiler set cannot resolve individuals and populations completely. Here, 52 centers generated quality-controlled data of 13 rapidly mutating (RM) Y-STRs in 14,644 related and unrelated males from 111 worldwide populations. Strikingly, >99% of the 12,272 unrelated males were completely individualized. Haplotype diversity was extremely high (global: 0.9999985, regional: 0.99836-0.9999988). Haplotype sharing between populations was almost absent except for six (0.05%) of the 12,156 haplotypes. Haplotype sharing within populations was generally rare (0.8% nonunique haplotypes), significantly lower in urban (0.9%) than rural (2.1%) and highest in endogamous groups (14.3%). Analysis of molecular variance revealed 99.98% of variation within populations, 0.018% among populations within groups, and 0.002% among groups. Of the 2,372 newly and 156 previously typed male relative pairs, 29% were differentiated including 27% of the 2,378 father-son pairs. Relative to Yfiler, haplotype diversity was increased in 86% of the populations tested and overall male relative differentiation was raised by 23.5%. Our study demonstrates the value of RMY-STRs in identifying and separating unrelated and related males and provides a reference database. Published 2014 Wiley Periodicals, Inc.**

Escherichia coli est le germe le plus fréquemment isolé surtout dans les infections urinaires. Son profil de sensibilité aux β-lactamines est en changement perpétuel sous l’effet de facteurs évolutifs, certaines souches acquièrent une résistance par mutations de gènes ou par acquisition de matériel génétique mobile. Ainsi, des phénomènes d’imperméabilité, d’excrétion par système d’efflux ou de modification des protéines de liaison aux pénicillines peuvent s’observer mais la production de β-lactamases constitue actuellement le mécanisme de résistance le plus rencontré chez Escherichia coli. Les auteurs rapportent le cas d’une souche particulière d’Escherichia coli isolée à partir des urines d’une patiente. Celle-ci se distinguait par un mécanisme de résistance d’apparition récente : l’hyperproduction de céphalosporinases. La mise en évidence phénotypique de ce mécanisme a nécessité le recours à des tests bactériologiques spécifiques tels que le test de synergie, le test d’antagonisme ou l’antibiogramme sur milieu Müeller-Hinton additionné de cloxacilline. Les auteurs évoquent également les mécanismes génétiques sous jacents à travers les données récentes de la littérature. Ils soulignent, par ailleurs, l’importance des précautions à prendre en terme de prescription d’antibiotiques rendant impérieux l’usage préalable de l’antibiogramme afin d’éviter la pression de sélection exercée sur le germe à l’origine de résistances difficilement maîtrisables et des complications qui en découlent., Maroc Médical, Vol. 30, No 1 (2008)

Listeria monocytogènes est une bactérie pathogène opportuniste. La listériose est une infection fréquente chez les sujets à immunité diminuée tel que les patients traités par les immunosuppresseurs. Nous rapportons un cas de septicémie à Listeria monocytogènes, survenue chez une femme de 42 ans mise sous chimiothérapie pour cancer de sein, avec la particularité d’être accompagnée d’une diarrhée importante. Le diagnostic bactériologique avec l’antibiogramme ont été réalisés directement à partir des bouillons d’hémoculture ce qui a raccourci le délai de réponse à moins de 24 heures. Concernant cette patiente, un diagnostic précoce a permis d’assurer rapidement une prise en charge thérapeutique plus efficace., Maroc Médical, Vol. 29, No 3 (2007)

Maroc Médical, Vol. 27, No 3 (2005)

As part of the critical metals group, vanadium is an essential commodity for the low- and zero-CO2 energy generation, storage and transport. This contribution aims to carry out a review of the known vanadium ore sources and mineralizations located in Africa, which are highly diversified in their geological and mineralogical characteristics, and can be classified in: 1. Vanadiferous (titano)magnetite deposits; 2. Sandstone-hosted (U)-vanadium deposits; 3. Calcrete-hosted (U)-vanadium deposits; 4. Vanadate deposits; 5. Graphite-associated vanadium deposits; 6. Vanadium occurrences associated with laterite, bauxite, and phosphate ores. The economically most significant vanadium sources in Africa are associated with titanomagnetite layers in mafic–ultramafic layered magmatic intrusions (e.g., the Bushveld Complex in South Africa and the Great Dyke in Zimbabwe). Vanadium has been historically mined also in vanadate deposits deriving from the supergene alteration of Pb-Zn-Cu sulfide ores in Namibia and Zambia. Several areas in these countries, where potentially re-processable old tailings and slags have been accumulated, still have economic potential. Vanadium mineralizations are associated with graphite bodies in the Mozambique Metamorphic Belt. Vanadium is also enriched in uranium ores occurring in the Upper Paleozoic-Mesozoic Karoo continental sediments: typical examples are found in Botswana, South Africa, and Zimbabwe. Significant uranium-vanadium concentrations (where carnotite prevails) occur in relatively recent (Tertiary-Quaternary) calcrete duricrusts in paleo-fluviatile beds, which are widespread throughout the African continent. These derive from the weathering of U-(V)-fertile source rocks, which under favorable paleoclimatic conditions resulted in the vanadium precipitation in the critical zone. Variable vanadium amounts have been also recorded in iron ore deposits, phosphorites, and laterites, even though the phosphate deposits seem to have the most favorable characteristics for potentially economic vanadium concentrations. On the whole, South Africa holds the most significant vanadium ore resources globally. However, also many other African countries, where this metal could be profitably extracted as a by-product from other economic ores, will probably be at the forefront of vanadium production in the near future.

International audience

International audience; The W–Au, Pb–Zn–Ag, and Sb–Ba deposits of the polymetallic Tighza-Jbel Aouam district (central Meseta, Morocco), hosted in Paleozoic rocks surrounding late Variscan granite stocks, have been considered of magmatic-hydrothermal origin. The spatial distribution of the mineralization was attributed in early studies to zoning around a supposed hidden batholith. New geophysical data (El Dursi 2009) and U/Pb geochronology on zircon and monazite grains (this study) allow revision of this model, giving insights of a more complex setting and history for the Tighza-Jbel Aouam district. The W–Au mineralization formed at 295–280 Ma and is related to a magmatic event visible only in a large hydrothermal biotitic alteration halo, thus suggesting the presence of a hidden batholith. This mineralization cuts the granitic stocks that are dated at 320–300 Ma. From the occurrence of large veins, stockworks, sheeted veins, and disseminations in skarns, the W–Au deposit is considered similar to a porphyry-type deposit. The currently mined Pb–Zn–Ag deposit, which is spatially separated from the W–Au deposit, developed during an epithermal magmatic-hydrothermal episode dated at 254 ± 16 Ma. The polymetallic district of Tighza-Jbel Aouam thus appears to contain Cordilleran-style, porphyry-type mineralization (W–Au) followed by epithermal mineralization (Pb–Zn–Ag), both being related to pulses of calc-alkaline magmatism. Late Variscan and Permo-Triassic transpressive tectonics in the region localized magma emplacement and the generation of genetically associated hydrothermal fluids, with the magmas originating in the mantle and the continental crust.

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International audience