VLT/XSHOOTER and Subaru/MOIRCS spectroscopy of HUDF.YD3: no evidence for Lyman emission at z = 8.55

We present spectroscopic observations with VLT/XSHOOTER and Subaru/MOIRCS of a relatively bright Y-band drop-out galaxy in the Hubble Ultra Deep Field (HUDF), first selected by Bunker et al., McLure et al. and Bouwens et al. to be a likely z ≈ 8–9 galaxy on the basis of its colours in the Hubble Space Telescope (HST) Advanced Camera for Surveys and Wide Field Camera 3 images. This galaxy, HUDF.YD3 (also known as UDFy-38135539), has been targetted for VLT/SINFONI integral field spectroscopy by Lehnert et al., who published a candidate Lyman α emission line at z = 8.55 from this source. In our independent spectroscopy using two different infrared spectrographs (5 h with VLT/XSHOOTER and 11 h with Subaru/MOIRCS), we are unable to reproduce this line. We do not detect any emission line at the spectral and spatial location reported in Lehnert et al., despite the expected signal in our combined MOIRCS and XSHOOTER data being 5σ. The line emission also seems to be ruled out by the faintness of this object in recently extremely deep F105W (Y band) HST/WFC 3 imaging from HUDF12; the line would fall within this filter and such a galaxy should have been detected at YAB = 28.6 mag (∼20σ) rather than the marginal YAB ≈ 30 mag observed in the Y-band image, >3 times fainter than would be expected if the emission line was real. Hence, it appears highly unlikely that the reported Lyman α line emission at z > 8 is real, meaning that the highest redshift sources for which Lyman α emission has been seen are at z = 6.9-7.2. It is conceivable that Lyman α does not escape galaxies at higher redshifts, where the Gunn–Peterson absorption renders the Universe optically thick to this line. However, deeper spectroscopy on a larger sample of candidate z > 7 galaxies will be needed to test this

Serum thyrotropin and free thyroxine reference ranges as defined in a disease-free sample of French middle-aged adults

Background: The goal of this study was to provide reference ranges for thyrotropin (TSH) and free thyroxine (fT4) based on data collected from a disease-free sample of French middle-aged adults. Methods: A total of 3218 subjects participating in the Supplémentation en Vitamines et Minéraux Antioxydants (SU.VI.MAX) study had measurements for TSH, fT4 and urinary iodine concentrations. Thyroid volume and structure were evaluated using standardized ultrasonography. We selected a disease-free sample which included 2338 subjects (1313 females aged 35–60 years and 1025 males aged 45–60 years) with normal thyroid imaging, no previously reported thyroid disease or use of thyroid medication, and no risk factors for thyroid dysfunction. Distribution of TSH and fT4 was estimated in males and females. Results: The median (central 95% range) TSH serum concentrations for females were 1.79 mU/L (0.29–5.21 mU/L) for ages 35–44 years and 1.98 mU/L (0.27–6.94 mU/L) for ages 45–60 years (p<0.0001, for age). The median (central 95% range) for males 45–60-year-old was 1.63 mU/L (0.28–4.54 mU/L) (p<0.0001, for sex). Sex- and age-specific mean fT4 concentrations did not differ significantly (p=0.06) between males and females and (p=0.08) between female age groups. However, median fT4 concentrations between 45–60-year-old males and females differed (p<0.001). Conclusions: In middle-aged adults, the TSH distribution was associated with gender and, among females, with age. Stratification according to gender and age should be considered when TSH ranges are used in the diagnosis, treatment and monitoring of thyroid disease. Clin Chem Lab Med 2009;47:1497–505.Peer Reviewe

Maladies thyroïdiennes dans la cohorte SU.VI.MAX. Estimation de leur incidence, 1994-2002

info:eu-repo/semantics/publishe

Maladies thyroïdiennes dans la cohorte SU.VI.MAX :estimation de l’incidence et des facteurs de risque associés, France, 1994-2002

info:eu-repo/semantics/nonPublishe

Incidence and factors associated to morphological thyroid dysfunction in the Su.vi.max study, France, 1994-2002

info:eu-repo/semantics/nonPublishe

Incidence and factors associated to biological thyroid dysfunction in the Su.vi.max study, France, 1994-2002

info:eu-repo/semantics/nonPublishe