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The lymphogranuloma venereum ( LGV) outbreak described in the Netherlands in 2003, increased the interest in the genotyping of Chlamydia trachomatis. Although international surveillance programmes were implemented, these studies slowly decreased in the following years. Now data have revealed a new accumulation of LGV cases in those European countries with extended surveillance programmes. Between March 2009 and November 2011, a study was carried out to detect LGV cases in Madrid. The study was based on screening of C. trachomatis using commercial kits, followed by real-time pmpH- PCR discriminating LGV strains, and finally ompA gene was sequenced for phylogenetic reconstruction. Ninety-four LGV infections were identified. The number of cases increased from 10 to 30 and then to 54 during 2009-2011. Incidence of LGV was strongly associated with men who have sex with men; but in 2011, LGV cases were described in women and heterosexual men. Sixty-nine patients were also human immunodeficiency virus ( HIV) positive, with detectable viral loads at the moment of LGV diagnosis, suggesting a high-risk of co-transmission. In fact, in four patients the diagnosis of HIV was simultaneous with LGV infection. The conventional treatment with doxycycline was prescribed in 75 patients, although in three patients the treatment failed. The sequencing of the ompA gene permitted identification of two independent transmission nodes. One constituted by 25 sequences identical to the L2b variant, and a second node including 37 sequences identical to L2. This epidemiological situation characterized by the co-circulation of two LGV variants has not been previously described, reinforcing the need for screening and genotyping of LGV strains. [ABSTRACT FROM AUTHOR]

Carbonate rocks are well-known to be tremendously heterogeneous. They mainly consist of component particles (from biological and non-biological origin) embedded in a lime-mud matrix and/or in a cement (composed of even smaller particles). The size, shape, density and spatial arrangement of those particles, alongside with natural fractures and cracks (although those are certainly not exclusive to carbonate rocks), define a microstructural pattern that is known to have a great influence on rock physical properties. Thus, to understand carbonate rock systems at large scales (formation, reservoir ...), geophysicists have to study them at the pore scale, hoping to resolve the so-called "upscalling" problem. With this in mind, unravelling and identifying the relations between physical properties and carbonate rock microstructures is paramount for a global comprehension of a carbonate rock system. Since the late nineties, several research groups and authors have worked on documenting and providing significant insights into the microstructural parameters controlling the physical response of several rock properties (porosity, permeability, electrical conductivity, elastic, seismic and mechanical properties ...) in carbonates. This article proposes a review of this specialized literature, from the early and recent contributions in rock physics, with emphasis on the recent studies on carbonate rocks from the Paris basin. • Rock physical properties are linked to many microstructural parameters. • Those parameters can interact at many different scales. • Early studies on those problems discussed the geological concepts of pore systems. • Recent work have shown that pore space must be defined using geometrical factors. • This concerns both elastic and transport properties in carbonate rocks. [ABSTRACT FROM AUTHOR]

Objectives Sexually transmitted infections are frequently related to outbreaks in high-risk populations due to the dense sexual networks. We wanted to determine the dissemination of a Chlamydia trachomatis variant characterized by the pmpH -recombinant gene between L and G genotypes, which was previously described in a high-risk population. Methods A total of 449 samples were analysed in two periods ranging from 2009 to 2015 for detection of the pmpH -recombinant gene. For those samples yielding positive amplification, a sampling was selected for phylogenetic reconstructions based on sequencing of five chromosomal genes. Results Globally this variant was found in 113 of the 449 samples (25%). During the first years (2009–13), this variant was found almost exclusively in rectal samples (30/112 samples) of men who have sex with men and in only one non-rectal sample (1/63). In 2014, this variant was also found in urethral and pharyngeal samples (1/24 and 1/7, respectively). However, in 2015, an epidemiological change was observed as the proportion of this variant had increased in rectal samples (20/51; 39%) and non-rectal samples, including cervical samples (51/142; 36.4%). The molecular characterization revealed the replacement of the ompA gene belonging to subtype G in samples recovered from 2009 to 2013 by the ompA gene belonging to subtype J after 2013. Conclusions Our data would support the evidence that subtype J could be a ‘subtype bridge’ between different sexual networks, as subtype J has been found in men who have sex with men and heterosexual populations in similar proportions. This work reveals the necessity of implementing molecular surveillance in extra-rectal samples to help us understand the gaps in transmission. [ABSTRACT FROM AUTHOR]

Abstract: Microstructural analysis of two undeformed sandstones, the Bentheim and Rothbach sandstones, supports the origin of the macroscopic anisotropies previously investigated (ultrasonic P-wave velocity, electrical conductivity and magnetic susceptibility). The shape and spatial distribution of both grains and voids were determined by computer image processing, measurement of magnetic anisotropy coupled with ferrofluids and stereological analysis. In addition, data on permeability measured in different directions are also provided for the two sandstones. The elastic models proposed in a previous paper are confirmed by the present study. In the Bentheim sandstone, the anisotropic behaviour was attributed to the non-spherical shape of the porosity, while in the Rothbach sandstone, an orientation-dependent cement radius at the intergranular contacts controls the observed anisotropy. The methods used for analysing the rock microstructure and its anisotropy are shown to be very useful and appropriate for detecting features such as pore or grain shape anisotropy, or the spatial distribution of grain contacts. [Copyright &y& Elsevier]