Sub-femto-g free fall for space-based gravitational wave observatories: LISA pathfinder results

We report the first results of the LISA Pathfinder in-flight experiment. The results demonstrate that two free-falling reference test masses, such as those needed for a space-based gravitational wave observatory like LISA, can be put in free fall with a relative acceleration noise with a square root of the power spectral density of 5.2 ± 0.1 fm s−2/√Hz or (0.54 ± 0.01) × 10−15 g/√Hz, with g the standard gravity, for frequencies between 0.7 and 20 mHz. This value is lower than the LISA Pathfinder requirement by more than a factor 5 and within a factor 1.25 of the requirement for the LISA mission, and is compatible with Brownian noise from viscous damping due to the residual gas surrounding the test masses. Above 60 mHz the acceleration noise is dominated by interferometer displacement readout noise at a level of (34.8 ± 0.3) fm/√Hz, about 2 orders of magnitude better than requirements. At f ≤ 0.5 mHz we observe a low-frequency tail that stays below 12 fm s−2/√Hz down to 0.1 mHz. This performance would allow for a space-based gravitational wave observatory with a sensitivity close to what was originally foreseen for LISA

Genotypes of sickle cell disease

CYP2C19 is a polymorphic enzyme that metabolizes a wide variety of therapeutic drugs that has been associated with altered enzymatic activity and adverse drug reactions. Differences in allele frequencies of the CYP2C19 gene have been detected in populations worldwide. Thus, we analysed the alleles CYP2C19*2, CYP2C19*3, CYP2C19*4 and CYP2C19*5 related to the poor metabolizer (PM) phenotype in a Mexican population sample (n = 238), as well as CYP2C19*17, unique allele related to ultrarapid metabolizer phenotype (UMs). Genotypes were determined using SNaPshot and TaqMan qPCR assays. In addition to the wild-type CYP2C19*1 allele (77.1%), we only found CYP2C19*17 (14.3%) and CYP2C19*2 (8.6%). Comparison with previous population reports demonstrated that these two SNPs are homogeneously distributed in Latin America (P>0.05). Based on comparison with a previous pharmacokinetic study that determined the frequency of CYP2C19 phenotypes in the same population (western Mexican), we obtained the following findings: (i) based on the difference between the frequency of genotypes CYP2C19*2/*2 (presumably PM) versus the observed prevalence of PM phenotypes (0.4 versus 6.3%; ?2=9.58, P = 0.00196), we inferred the plausible presence of novel CYP2C19 alleles related to the PM phenotype; (ii) the prevalence of UMs was in disagreement with the dominant inheritance pattern suggested for CYP2C19*17 (23.1 versus 4%; P<0.00001); (iii) the apparent recessive inheritance pattern of CYP2C19*17, based on the agreement between homozygous CYP2C19*17/*17 (presumably UMs) and the observed prevalence of UMs (2.1 versus 4%; (?2=1.048; P = 0.306). " 2015 Indian Academy of Sciences",,,,,,"10.1007/s12041-015-0477-1",,,"http://hdl.handle.net/20.500.12104/41716","http://www.scopus.com/inward/record.url?eid=2-s2.0-84923261662&partnerID=40&md5=609b3d0e44d0e37b92420aa5676bfb1

Genetic variability of CYP2C19 in a Mexican population: contribution to the knowledge of the inheritance pattern of CYP2C19*17 to develop the ultrarapid metabolizer phenotype

CYP2C19 is a polymorphic enzyme that metabolizes a wide variety of therapeutic drugs that has been associated with altered enzymatic activity and adverse drug reactions. Differences in allele frequencies of the CYP2C19 gene have been detected in populations worldwide. Thus, we analysed the alleles CYP2C19*2, CYP2C19*3, CYP2C19*4 and CYP2C19*5 related to the poor metabolizer (PM) phenotype in a Mexican population sample (n = 238), as well as CYP2C19*17, unique allele related to ultrarapid metabolizer phenotype (UMs). Genotypes were determined using SNaPshot and TaqMan qPCR assays. In addition to the wild-type CYP2C19*1 allele (77.1%), we only found CYP2C19*17 (14.3%) and CYP2C19*2 (8.6%). Comparison with previous population reports demonstrated that these two SNPs are homogeneously distributed in Latin America (P>0.05). Based on comparison with a previous pharmacokinetic study that determined the frequency of CYP2C19 phenotypes in the same population (western Mexican), we obtained the following findings: (i) based on the difference between the frequency of genotypes CYP2C19*2/*2 (presumably PM) versus the observed prevalence of PM phenotypes (0.4 versus 6.3%; χ2=9.58, P = 0.00196), we inferred the plausible presence of novel CYP2C19 alleles related to the PM phenotype; (ii) the prevalence of UMs was in disagreement with the dominant inheritance pattern suggested for CYP2C19*17 (23.1 versus 4%; P<0.00001); (iii) the apparent recessive inheritance pattern of CYP2C19*17, based on the agreement between homozygous CYP2C19*17/*17 (presumably UMs) and the observed prevalence of UMs (2.1 versus 4%; (χ2=1.048; P = 0.306). © 2015 Indian Academy of Science

Ten millennia of hepatitis B virus evolution

Hepatitis B virus (HBV) has been infecting humans for millennia and remains a global health problem, but its past diversity and dispersal routes are largely unknown. We generated HBV genomic data from 137 Eurasians and Native Americans dated between ~10,500 and ~400 years ago. We date the most recent common ancestor of all HBV lineages to between ~20,000 and 12,000 years ago, with the virus present in European and South American hunter-gatherers during the early Holocene. After the European Neolithic transition, Mesolithic HBV strains were replaced by a lineage likely disseminated by early farmers that prevailed throughout western Eurasia for ~4000 years, declining around the end of the 2nd millennium BCE. The only remnant of this prehistoric HBV diversity is the rare genotype G, which appears to have reemerged during the HIV pandemic