1,180 research outputs found

    Endometriosis and Organochlorinated Environmental Pollutants: A Case–Control Study on Italian Women of Reproductive Age

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    BACKGROUND: Endometriosis is a common gynecologic disease characterized by the ectopic growth of endometrial tissue. In industrialized countries, it affects approximately 10% of women of reproductive age. Its etiology is unclear, but a multifactorial origin is considered to be most plausible. Environmental organochlorinated persistent pollutants, in particular dioxins and polychlorinated biphenyls (PCBs), have been hypothesized to play a role in the disease etiopathogenesis. However, results of studies carried out on humans are conflicting. OBJECTIVE: We evaluated the exposure to organochlorinated persistent pollutants as a risk factor for endometriosis. METHODS: We conducted a case-control study in Rome on 158 women comprising 80 cases and 78 controls. In all women, serum concentrations of selected non-dioxin-like PCBs (NDL-PCBs) and dioxin-like PCBs (DL-PCBs), 1,1-dichloro-2,21-bis(4-chlorophenyl)-ethene (p p'-DDE), and hexachlorobenzene (HCB) were determined by ion-trap mass spectrometry. DR-CALUX bioassay was employed to assess the 2,3,7,8-tetrachlorodibenzo-p-dioxin toxicity equivalent (TEQ) concentrations of polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), and DL-PCBs. RESULTS: We found an increased risk of endometriosis for DL-PCB-118 (odds ratio (OR) = 3.79; 95% confidence interval (CI), 1.61-8.91), NDL-PCB-138 (OR = 3.78; 95% CI, 1.60-8.94), NDLPCB-153 (OR = 4.88; 95% CI, 2.01-11.0), NDL-PCB-170 (OR = 3.52; 95% CI, 1.41-8.79), and the sum of DL-PCBs and NDL-PCBs (OR = 5.63; 95% CI, 2.25-14. 10). No significant associations were observed with respect to HCB or to the sum of PCDDs, PCDFs1 and DL-PC13s given as total TEQs. CONCLUSIONS: The results of this study show that an association exists between increased PCB and p,p'-DDE serum concentrations and the risk of endometriosis

    The association of impaired semen quality and pregnancy rates in assisted reproduction technology cycles: Systematic review and meta-analysis

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    Some studies suggest a relationship between semen quality and pregnancy rates of assisted reproduction technologies (ART). Others have questioned the utility of semen quality as proxy for fertility in couples attempting to conceive with or without assistance. We aimed to investigate the current body of evidence which correlates semen parameters and clinical pregnancy among couples utilizing ART (i.e. in vitro fertilization [IVF], intracytoplasmic sperm injection [ICSI]) through a systematic review and meta-analysis of cross-sectional and retrospective cohort studies. Pooled Odd Ratio (OR) for oligo-, astheno- and teratospermic compared to normospermic number of ART cycles were calculated among. Meta-regression and sub-group analysis were implemented to model the contribution of clinical/demographic and laboratory standards differences among the studies. Overall, 17 studies were analysed representing 17,348 cycles were analysed. Pooled OR for impaired sperm concentration, motility and morphology was 1 (95%Confidence Interval [CI]: 0.97-1.03), 0.88 (95%CI: 0.73-1.03) and 0.88 (95%CI: 0.75-1) respectively. Further analysis on sperm morphology showed no differences with regard of IVF versus ICSI (p = 0.14) nor a significant correlation with rising reference thresholds (Coeff: -0.02, p = 0.38). A temporal trend towards a null association between semen parameters and clinical pregnancy was observed over the 20-year observation period (Coeff: 0.01, p = 0.014). The current analysis found no association between semen quality (as measured by concentration, motility or morphology) and clinical pregnancy rates utilizing ART. Future investigations are necessary to explore the association between semen parameters and other ART outcomes (e.g. fertilization, implantation, birth and perinatal health)

    Genetic risk factors for ischaemic stroke and its subtypes (the METASTROKE Collaboration): a meta-analysis of genome-wide association studies

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    <p>Background - Various genome-wide association studies (GWAS) have been done in ischaemic stroke, identifying a few loci associated with the disease, but sample sizes have been 3500 cases or less. We established the METASTROKE collaboration with the aim of validating associations from previous GWAS and identifying novel genetic associations through meta-analysis of GWAS datasets for ischaemic stroke and its subtypes.</p> <p>Methods - We meta-analysed data from 15 ischaemic stroke cohorts with a total of 12 389 individuals with ischaemic stroke and 62 004 controls, all of European ancestry. For the associations reaching genome-wide significance in METASTROKE, we did a further analysis, conditioning on the lead single nucleotide polymorphism in every associated region. Replication of novel suggestive signals was done in 13 347 cases and 29 083 controls.</p> <p>Findings - We verified previous associations for cardioembolic stroke near PITX2 (p=2·8×10−16) and ZFHX3 (p=2·28×10−8), and for large-vessel stroke at a 9p21 locus (p=3·32×10−5) and HDAC9 (p=2·03×10−12). Additionally, we verified that all associations were subtype specific. Conditional analysis in the three regions for which the associations reached genome-wide significance (PITX2, ZFHX3, and HDAC9) indicated that all the signal in each region could be attributed to one risk haplotype. We also identified 12 potentially novel loci at p<5×10−6. However, we were unable to replicate any of these novel associations in the replication cohort.</p> <p>Interpretation - Our results show that, although genetic variants can be detected in patients with ischaemic stroke when compared with controls, all associations we were able to confirm are specific to a stroke subtype. This finding has two implications. First, to maximise success of genetic studies in ischaemic stroke, detailed stroke subtyping is required. Second, different genetic pathophysiological mechanisms seem to be associated with different stroke subtypes.</p&gt

    Design of the ExCersion-VCI study: The effect of aerobic exercise on cerebral perfusion in patients with vascular cognitive impairment

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    There is evidence for a beneficial effect of aerobic exercise on cognition, but underlying mechanisms are unclear. In this study, we test the hypothesis that aerobic exercise increases cerebral blood flow (CBF) in patients with vascular cognitive impairment (VCI). This study is a multicenter single-blind randomized controlled trial among 80 patients with VCI. Most important inclusion criteria are a diagnosis of VCI with Mini-Mental State Examination ≥22 and Clinical Dementia Rating ≤0.5. Participants are randomized into an aerobic exercise group or a control group. The aerobic exercise program aims to improve cardiorespiratory fitness and takes 14 weeks, with a frequency of three times a week. Participants are provided with a bicycle ergometer at home. The control group receives two information meetings. Primary outcome measure is change in CBF. We expect this study to provide insight into the potential mechanism by which aerobic exercise improves hemodynamic status

    Search for CP violation in D+→ϕπ+ and D+s→K0Sπ+ decays

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    A search for CP violation in D + → ϕπ + decays is performed using data collected in 2011 by the LHCb experiment corresponding to an integrated luminosity of 1.0 fb−1 at a centre of mass energy of 7 TeV. The CP -violating asymmetry is measured to be (−0.04 ± 0.14 ± 0.14)% for candidates with K − K + mass within 20 MeV/c 2 of the ϕ meson mass. A search for a CP -violating asymmetry that varies across the ϕ mass region of the D + → K − K + π + Dalitz plot is also performed, and no evidence for CP violation is found. In addition, the CP asymmetry in the D+s→K0Sπ+ decay is measured to be (0.61 ± 0.83 ± 0.14)%

    Influenza A Viruses from Wild Birds in Guatemala Belong to the North American Lineage

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    The role wild bird species play in the transmission and ecology of avian influenza virus (AIV) is well established; however, there are significant gaps in our understanding of the worldwide distribution of these viruses, specifically about the prevalence and/or significance of AIV in Central and South America. As part of an assessment of the ecology of AIV in Guatemala, we conducted active surveillance in wild birds on the Pacific and Atlantic coasts. Cloacal and tracheal swab samples taken from resident and migratory wild birds were collected from February 2007 to January 2010.1913 samples were collected and virus was detected by real time RT-PCR (rRT-PCR) in 28 swab samples from ducks (Anas discors). Virus isolation was attempted for these positive samples, and 15 isolates were obtained from the migratory duck species Blue-winged teal. The subtypes identified included H7N9, H11N2, H3N8, H5N3, H8N4, and H5N4. Phylogenetic analysis of the viral sequences revealed that AIV isolates are highly similar to viruses from the North American lineage suggesting that bird migration dictates the ecology of these viruses in the Guatemalan bird population

    Search for the standard model Higgs boson at LEP

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    X-ray emission from the Sombrero galaxy: discrete sources

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    We present a study of discrete X-ray sources in and around the bulge-dominated, massive Sa galaxy, Sombrero (M104), based on new and archival Chandra observations with a total exposure of ~200 ks. With a detection limit of L_X = 1E37 erg/s and a field of view covering a galactocentric radius of ~30 kpc (11.5 arcminute), 383 sources are detected. Cross-correlation with Spitler et al.'s catalogue of Sombrero globular clusters (GCs) identified from HST/ACS observations reveals 41 X-rays sources in GCs, presumably low-mass X-ray binaries (LMXBs). We quantify the differential luminosity functions (LFs) for both the detected GC and field LMXBs, whose power-low indices (~1.1 for the GC-LF and ~1.6 for field-LF) are consistent with previous studies for elliptical galaxies. With precise sky positions of the GCs without a detected X-ray source, we further quantify, through a fluctuation analysis, the GC LF at fainter luminosities down to 1E35 erg/s. The derived index rules out a faint-end slope flatter than 1.1 at a 2 sigma significance, contrary to recent findings in several elliptical galaxies and the bulge of M31. On the other hand, the 2-6 keV unresolved emission places a tight constraint on the field LF, implying a flattened index of ~1.0 below 1E37 erg/s. We also detect 101 sources in the halo of Sombrero. The presence of these sources cannot be interpreted as galactic LMXBs whose spatial distribution empirically follows the starlight. Their number is also higher than the expected number of cosmic AGNs (52+/-11 [1 sigma]) whose surface density is constrained by deep X-ray surveys. We suggest that either the cosmic X-ray background is unusually high in the direction of Sombrero, or a distinct population of X-ray sources is present in the halo of Sombrero.Comment: 11 figures, 5 tables, ApJ in pres

    Search for supersymmetric particles in scenarios with a gravitino LSP and stau NLSP

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    Sleptons, neutralinos and charginos were searched for in the context of scenarios where the lightest supersymmetric particle is the gravitino. It was assumed that the stau is the next-to-lightest supersymmetric particle. Data collected with the DELPHI detector at a centre-of-mass energy near 189 GeV were analysed combining the methods developed in previous searches at lower energies. No evidence for the production of these supersymmetric particles was found. Hence, limits were derived at 95% confidence level.Comment: 31 pages, 14 figure

    Performance of CMS muon reconstruction in pp collision events at sqrt(s) = 7 TeV

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    The performance of muon reconstruction, identification, and triggering in CMS has been studied using 40 inverse picobarns of data collected in pp collisions at sqrt(s) = 7 TeV at the LHC in 2010. A few benchmark sets of selection criteria covering a wide range of physics analysis needs have been examined. For all considered selections, the efficiency to reconstruct and identify a muon with a transverse momentum pT larger than a few GeV is above 95% over the whole region of pseudorapidity covered by the CMS muon system, abs(eta) < 2.4, while the probability to misidentify a hadron as a muon is well below 1%. The efficiency to trigger on single muons with pT above a few GeV is higher than 90% over the full eta range, and typically substantially better. The overall momentum scale is measured to a precision of 0.2% with muons from Z decays. The transverse momentum resolution varies from 1% to 6% depending on pseudorapidity for muons with pT below 100 GeV and, using cosmic rays, it is shown to be better than 10% in the central region up to pT = 1 TeV. Observed distributions of all quantities are well reproduced by the Monte Carlo simulation.Comment: Replaced with published version. Added journal reference and DO
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