A large and complete sample of stars with K < 9.75 in the NGC 6522 Baade's Window towards the Galactic bulge is examined using light curves extracted from MACHO and IJK photometry from DENIS. The ...improved statistics resulting from a sample of over 1000 variables allow all four of the sequences A, B, C and D in the KS, log P diagram of the Large Magellanic Cloud to be seen in the Galactic bulge. The bulge sequences, however, show some differences from those in the Magellanic Clouds, possibly due to the effects of higher metallicity. These sequences may have value as distance indicators. A new diagram of the frequency of late-type variables at a given amplitude is derived and compared with the old one from Payne-Gaposchkin. The catalogued semiregular variables of the solar neighbourhood are found to be a subset of the total of semiregulars, biased towards large amplitude.
Context. The stellar populations in the central region of the Galaxy are poorly known because of the high visual extinction and very great source density in this direction. Aims. To use recent ...infrared surveys for studying the dusty stellar objects in this region. Methods. We analyse the content of a similar to 20 x 20 arcmin super(2) field centred at (l, b) = (-0.27 degree , -0.06 degree ) observed at 7 and 15 mu m as part of the ISOGAL survey. These ISO observations are more than an order of magnitude better in sensitivity and spatial resolution than the IRAS observations. The sources are cross-associated with other catalogues to identify various types of objects. We then derive criteria to distinguish young objects from post-main sequence stars. Results. We find that a sample of about 50 young stellar objects and ultra-compact HII regions emerges, out of a population of evolved AGB stars. We demonstrate that the sources colours and spatial extents, as they appear in the ISOGAL catalogue, possibly complemented with MSX photometry at 21 jum, can be used to determine whether the ISOGAL sources brighter than 300 mJy at 15 mu m (or 15 less than or equal to 4.5 mag) are young objects or late-type evolved stars.
We used the Immunochip array to analyze 2,816 individuals with juvenile idiopathic arthritis (JIA), comprising the most common subtypes (oligoarticular and rheumatoid factor-negative polyarticular ...JIA), and 13,056 controls. We confirmed association of 3 known JIA risk loci (the human leukocyte antigen (HLA) region, PTPN22 and PTPN2) and identified 14 loci reaching genome-wide significance (P < 5 × 10(-8)) for the first time. Eleven additional new regions showed suggestive evidence of association with JIA (P < 1 × 10(-6)). Dense mapping of loci along with bioinformatics analysis refined the associations to one gene in each of eight regions, highlighting crucial pathways, including the interleukin (IL)-2 pathway, in JIA disease pathogenesis. The entire Immunochip content, the HLA region and the top 27 loci (P < 1 × 10(-6)) explain an estimated 18, 13 and 6% of the risk of JIA, respectively. In summary, this is the largest collection of JIA cases investigated so far and provides new insight into the genetic basis of this childhood autoimmune disease.
M giants in MACHO, DENIS and ISOGAL Glass, I. S.; Schultheis, M.
Monthly notices of the Royal Astronomical Society,
12/2002, Volume:
337, Issue:
2
Journal Article
Peer reviewed
Open access
A ‘complete’ sample of 174 M giants classified in the mid-1980s by Blanco and later than subtype M0 in the NGC 6522 Baade's Window clear field has been investigated to establish some general ...properties of cool bulge stars. Photometric information has been obtained from the MACHO data base to search for variability and, where possible, to determine periods. Near- and mid-infrared magnitudes have been extracted from DENIS and ISOGAL. 46 semiregular variables (SRVs) and two irregular variables were found amongst the 174. Many M5 and all stars M6 or later show variation, whereas earlier subtypes (M1–M4) do not. The DENIS I — J and J — KS colours and the luminosities of the M stars increase with M subclass. K tends to increase with log P among the M-type SRVs. Almost all the variables were detected at 7 μm during the ISOGAL programme. Excess radiation at 15 μm, indicative of heavy mass loss, is associated with high luminosity and late spectral type. The limit of sensitivity of the ISOGAL survey was such that the non-variables were not detected. Four probable M stars not listed by Blanco, two of which are semiregular variables, were detected by ISOGAL. In the case of doubly periodic SRVs, the longer periods have K magnitudes that place them close to the ‘D’ line of Wood in a K—log P diagram. The unusual MACHO light curve of one particular star, Blanco 26, shows the commencement of a long-period variation with an anomalously short and sharp event and appears to rule out a pulsational model for this phenomenon.
Nef is an important pathogenesis factor of HIV-1 with a multitude of effector functions. We have designed a broad panel of isogenic viruses encoding defined mutants of HIV-1
SF2 Nef and analyzed ...their biological activity in the context of productive HIV-1 infection. Analysis of subcellular localization, virion incorporation, downregulation of cell surface CD4 and MHC-I, enhancement of virion infectivity and facilitation of HIV replication in primary human T lymphocytes mostly confirmed the mapping of Nef determinants previously reported upon isolated expression of Nef. However, reduced activity in downregulation of CD4, infectivity enhancement and virion incorporation of a Nef variant (Δ12–39) lacking an amphipatic helix required for binding of a cellular kinase complex and the association of Nef with MHC-I/AP-1 suggested a novel role of this N-terminal motif. The SH3 binding motif of Nef was partially required for infectivity enhancement and replication but not for receptor downmodulation. In contrast to previous results obtained using other Nef alleles, non-myristoylated SF2-Nef was only partly defective when expressed during HIV infection and was present in HIV-1 particles. Importantly, incorporation of Nef into HIV-1 virions was not required for any of the tested Nef activities. Altogether, this study provides a broad characterization and mapping of multiple Nef activities in HIV-infected cells. The results emphasize that multiple activities govern Nef's effects on HIV replication and argue against a role of virion incorporation for Nef's activity as pathogenicity factor.
Background: Annual Pap smear screening has been favored over less frequent screening in the United States to minimize the risk of cervical cancer. We evaluated whether simultaneous screening with a ...Pap test and human papillomavirus (HPV) testing is useful for assessing the risk for cervical intraepithelial neoplasia (CIN) 3 or cervical cancer. Methods: We enrolled 23 702 subjects in a study of HPV infection at Kaiser Permanente, Northwest Division, Portland, OR. Data were analyzed for 20 810 volunteers who were at least 16 years old (mean = 35.9 years) with satisfactory baseline Pap tests and suitable samples for HPV testing. Women were followed for up to 122 months (from April 1, 1989, to June 30, 1999) to determine the risk for histopathologically confirmed CIN3 or cancer. Results: Among 171 women with CIN3 or cancer diagnosed over 122 months, 123 (71.9%, 95% confidence interval CI = 65.2% to 78.7%) had baseline Pap results of atypical squamous cells or worse and/or a positive HPV test, including 102 (86.4%, 95% CI = 80.3% to 92.6%) of the 118 cases diagnosed within the first 45 months of follow-up. During this 45-month period, the cumulative incidence of CIN3 or cancer was 4.54% (95% CI = 3.61% to 5.46%) among women with a Pap test result of atypical squamous cells or worse, positive HPV tests, or both compared with 0.16% (95% CI = 0.08% to 0.24%) among women with negative Pap and HPV tests. Age, screening behavior, a history of cervical cancer precursors, and a history of treatment for CIN minimally affected results. Conclusions: Negative baseline Pap and HPV tests were associated with a low risk for CIN3 or cancer in the subsequent 45 months, largely because a negative HPV test was associated with a decreased risk of cervical neoplasia. Negative combined test results should provide added reassurance for lengthening the screening interval among low-risk women, whereas positive results identify a relatively small subgroup that requires more frequent surveillance.
Objective To assess the performance of a tandem mass spectrometry (MS/MS) technology in a newborn screening laboratory to simultaneously measure α-galactosidase, acid-α-glucosidase, and ...α-L-iduronidase for the detection of infants at risk to develop Fabry, Pompe, or mucopolysaccharidosis (MPS)-I diseases. Study design Enzyme activity was assayed from a 3.2-mm punch from 100 000+ anonymous newborn blood spots. Punches with low enzyme activity were further evaluated by nucleotide sequence analysis of the responsible gene. Confirmation of affected infants was dependent on identification of mutations compatible with diminished enzyme activity. Results The technology for simultaneously measuring multiple enzyme activities by MS/MS was successful. The confirmation of diagnosis for Fabry, Pompe, or MPS-I, by DNA sequencing estimated the prevalence of Fabry disease at 1/7800 males (95% CI 1/17 800-1/3600); Pompe disease at 1/27 800 newborns (95% CI 1/90 000-1/10 200); and MPS-I at 1/35 500 newborns (95% CI 1/143 000-1/11 100). These estimates of prevalence are 2 to 4 times greater than the prevalence estimated by clinical diagnosis. The combined prevalence for the 3 disorders was 1/7500 newborns (95% CI 1/13 500-1/4500). Conclusions MS/MS for the simultaneous assay of multiple lysosomal enzymes can be successfully introduced into a routine newborn screening laboratory. The technology has a positive predictive value equal to, or better, than methods currently used for the detection of nonlysosomal disorders. Using newborn blood spots, the combined prevalence of Fabry, Pompe, and MPS-I is estimated at 1/7500 newborns based on low-enzyme activity and confirmation by mutation analysis.
The ISOGAL project is an infrared survey of specific regions sampling the Galactic Plane selected to provide information on Galactic structure, stellar populations, stellar mass-loss and the recent ...star formation history of the inner disk and Bulge of the Galaxy. ISOGAL combines 7 and 15 μm ISOCAM observations – with a resolution of 6″ at worst – with DENIS IJKs data to determine the nature of the sources and the interstellar extinction. We have observed about 16 square degrees with a sensitivity approaching 10–20 mJy, detecting ~105 sources, mostly AGB stars, red giants and young stars. The main features of the ISOGAL survey and the observations are summarized in this paper, together with a brief discussion of data processing and quality. The primary ISOGAL products are described briefly (a full desciption is given in Schuller et al. 2003): viz. the images and the ISOGAL–DENIS five-wavelength point source catalogue. The main scientific results already derived or in progress are summarized. These include astrometrically calibrated 7 and 15 μm images, determining structures of resolved sources; identification and properties of interstellar dark clouds; quantification of the infrared extinction law and source dereddening; analysis of red giant and (especially) AGB stellar populations in the central Bulge, determining luminosity, presence of circumstellar dust and mass-loss rate, and source classification, supplemented in some cases by ISO/CVF spectroscopy; detection of young stellar objects of diverse types, especially in the inner Bulge with information about the present and recent star formation rate; identification of foreground sources with mid-IR excess. These results are the subject of about 25 refereed papers published or in preparation.
PDF
