128 research outputs found

    Sperm parameters and DNA fragmentation of balanced chromosomal rearrangements carriers

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    Introduction. Somatic chromosomal rearrangements that occur in infertile males are thought to be one of the major genetic factors influencing male infertility. The objective of this retrospective study was to evaluate sperm parameters in a group of patients with balanced translocations. Material and methods. We analyzed semen of 84 balanced somatic translocation carriers [35 Robertsonian translocation (RT group) and 49 reciprocal translocation (RCT group)] and 57 men with normal karyotype (control group). Semen samples were evaluated for sperm concentration, its motion parameters and vitality, round cell number (CASA) and DNA fragmentation index (TUNEL). Cytogenetic evaluation was also performed for each study participant. Results. Sperm concentrations were lower when comparing the RT group to the control (p < 0.001) and RCT groups (p < 0.05). Occurrence of abnormal sperm concentration was more common among RT carriers (74.3%) than in the other groups (42.9% in RCT group and 28.1% in control group). The sperm progressive motility and vitality in RT carriers (21.53% and 62.17%) were lower than in control group (39.77% and 77.47%, p < 0.001, respectively) and RCT carriers (31.47% and 76.17%, p < 0.001, respectively). The RCT carriers and the control group did not differ in regard to sperm concentration, progressive sperm motility, motility grade D and sperm vitality. There were no significant differences in DNA fragmentation in carriers of both studied structural chro­mosomal rearrangements in comparison to subjects with normal karyotype. Conclusions. RT carriers had significantly lower semen parameters in comparison to not only the subjects with normal karyotypes but also the RCT carriers

    New limits on "odderon" amplitudes from analyticity constraints

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    In studies of high energy pppp and pˉp\bar pp scattering, the odd (under crossing) forward scattering amplitude accounts for the difference between the pppp and pˉp\bar pp cross sections. Typically, it is taken as f=p4πDsα1eiπ(1α)/2f_-=-\frac{p}{4\pi}Ds^{\alpha-1}e^{i\pi(1-\alpha)/2} (α0.5\alpha\sim 0.5), which has Δσ,Δρ0\Delta\sigma, \Delta\rho\to0 as ss\to\infty, where ρ\rho is the ratio of the real to the imaginary portion of the forward scattering amplitude. However, the odd-signatured amplitude can have in principle a strikingly different behavior, ranging from having Δσ\Delta\sigma\tonon-zero constant to having Δσlns/s0\Delta\sigma \to \ln s/s_0 as ss\to\infty, the maximal behavior allowed by analyticity and the Froissart bound. We reanalyze high energy pppp and pˉp\bar pp scattering data, using new analyticity constraints, in order to put new and precise limits on the magnitude of ``odderon'' amplitudes.Comment: 13 pages LaTex, 6 figure

    Two new automated, compared with two enzyme-linked immunosorbent, antimüllerian hormone assays

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    Objective: To compare new automated antimüllerian hormone (AMH) assay performance characteristics from the new automated Elecsys AMH (Roche; Elecsys) and Access AMH (Beckman Coulter; Access) assays with the existing AMH Gen II ELISA (enzyme-linked immunosorbent assay; Gen II; Beckman Coulter) and AMH ELISA (Ansh Labs) assays. Design: Prospective assay evaluation. Setting: University-affiliated clinical chemistry laboratory. Patient(s): Patients referred for serum AMH measurement (n = 83) before start of in vitro fertilization cycle between September 2014 and October 2014. Intervention(s): None. Main Outcome Measure(s): Serum AMH concentration.: Result(s): Intra-assay coefficients of variation were low; Ansh ≤ 9.0%; Gen II ≤ 5.8%; Access ≤ 10.7%; and Elecsys ≤ 2.8%. The Passing-Bablok regression equations (pmol/L) were y (Access) = 0.128 + (0.781 × Gen II); and y (Access) = 0.302 + (0.742 x Ansh). For y (Elecys) = 0.087 + (0.729 x Gen II) and y (Elecys) = 0.253 + (0.688 x Ansh Labs). For y (Elecys) = 0.943 − (0.037 × Access). For all the assays, AMH exhibited a moderate positive correlation with AFC (r = 0.62–0.64); number of cumulus oocyte complexes (r = 0.60–0.64); and metaphase II oocytes (r = 0.48–0.50). Accuracy of pregnancy prediction, as determined by area under the receiver operating characteristic curve, was uniformly low for all assays (0.62–0.63). Conclusion(s): The novel automated assays exhibit strong concordance in calibration, but derived values are substantially lower than those obtained from pre-existing assays, with assay-specific interpretation required for routine clinical use. These results highlight the need for an international standard of measurement of AMH

    Effects of R-Alpha Lipoic Acid on HbA1c, Lipids and Blood Pressure in Type-2 Diabetics: A Preliminary Study

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    R-alpha lipoic acid (R-ALA) supplementation improves blood glucose in diabetic animals, but there have been no long-term clinical trials in humans testing its use for glucose control (HbA1c). This double-blind study pre-/post-test control group (PL) design sought to determine the effect of R-ALA on HbA1c. Twenty type-2 diabetics were randomly assigned to 200 mg capsules of R-ALA (n=13; 8M 5F) or PL (n=7; 2M 5F) 3 times daily, 30 minutes before meals (600 mg total) for 91 days. Samples were obtained for HbA1c at baseline and day 91. No significant differences between R-ALA and PL groups were found at baseline or day 91. However, three distinct reactions to the supplement were noted. The first group (n=3) responded to R-ALA with a >25% drop in HbA1c range from 6.1-12.5 to 6.2- 9.0 mg/dL and/or halved their anti-diabetic medication. The second group (n=5) had no change in HbA1c. The third group (n=5) had changes in medication or concurrent chronic adverse events that should have raised HbA1c, but did not beyond that of the placebo. Conclusions: Three months of R-ALA supplementation may lower HbA1c in a small number of individuals. However, to further confirm these findings, larger studies of longer duration are needed

    Lattice approach to high-energy hadron-hadron scattering

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    We discuss the non perturbative approach to the problem of high-energy hadron-hadron (dipole-dipole) scattering at low momentum transfer by means of numerical simulations in Lattice Gauge Theory.Comment: 4 pages, 5 figures, LaTeX with espcrc2.sty (v. 2.7). To appear in the proceedings of the 14th International QCD Conference (QCD 08), Montpellier, France, 7-12 July 200

    Elastic pppp and pˉp\bar pp scattering in the models of unitarized pomeron

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    Elastic scattering amplitudes dominated by the Pomeron singularity which obey the principal unitarity bounds at high energies are constructed and analyzed. Confronting the models of double and triple (at t=0t=0) Pomeron pole (supplemented by some terms responsible for the low energy behaviour) with existing experimental data on pppp and pˉp\bar pp total and differential cross sections at s5\sqrt{s}\geq 5 GeV and t6|t|\leq 6 GeV2^{2} we are able to tune the form of the Pomeron singularity. Actually the good agreement with those data is received for both models though the behaviour given by the dipole model is more preferable in some aspects. The predictions made for the LHC energy values display, however, the quite noticeable difference between the predictions of models at t0.4t\approx -0.4 GeV2^{2}. Apparently the future results of TOTEM will be more conclusive to make a true choice.Comment: Revtex4, 8 pages, 5 figures. Text is improved, no changes in figures and conclusions. Version to be published in Phys. Rev.

    A classical Odderon in QCD at high energies

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    We show that the weight functional for color sources in the classical theory of the Color Glass Condensate includes a term which generates Odderon excitations. Remarkably, the classical origin of these excitations can be traced to the random walk of partons in the two dimensional space spanned by the SU(3) Casimirs. This term is naturally suppressed for a large nucleus at high energies.Comment: 19 pages. No figur

    Heisenberg's Universal (lns)**2 Increase of Total Cross Sections

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    The (lns)**2 behaviour of total cross-sections, first obtained by Heisenberg 50 years ago, receives now increased interest both on phenomenological and theoretical levels. In this paper we present a modification of the Heisenberg's model in connection with the presence of glueballs and we show that it leads to a realistic description of all existing hadron total cross-section data.Comment: 6 pages, 3 figure

    Non-equivalence of anti-Müllerian hormone automated assays—clinical implications for use as a companion diagnostic for individualised gonadotrophin dosing

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    STUDY QUESTION Can anti-Müllerian hormone (AMH) automated immunoassays (Elecsys® and Access) be used interchangeably as a companion diagnostic for individualisation of follitropin delta dosing? SUMMARY ANSWER The Access assay gives systematically higher AMH values than the Elecsys® assay which results in over 29% of women being misclassified to a different follitropin delta dose. WHAT IS KNOWN ALREADY Follitropin delta is the first gonadotrophin to be licenced with a companion diagnostic, the Roche Elecsys® AMH Plus assay. Alternative automated AMH assays including the Beckman Coulter Access immunoassay are considered to provide similar results, but clarification of their suitability as an off-licence companion diagnostic for follitropin delta is required. STUDY DESIGN, SIZE, DURATION We systematically searched the existing literature for studies that had measured AMH using both automated assays in the same cohort of women. Individual paired patient data were acquired from each author and combined with unpublished data. PARTICIPANTS/MATERIALS, SETTING, METHODS We identified five eligible prospective published studies and one additional unpublished study. A 100% response from the authors was achieved. We collected paired AMH data on samples from 848 women. Passing–Bablok regression and Bland–Altman plots were used to compare the analytical performance of the two assays. The degree of misclassification to different treatment categories was estimated should the Access AMH be used as a companion diagnostic instead of the Elecsys AMH in determining the dosing of follitropin delta. MAIN RESULTS AND THE ROLE OF CHANCE The Passing–Bablok regression shows a linear relationship (Access = −0.05 + 1.10 × Elecsys). The Access assay systematically gave higher values by an average of 10% compared with the Elecsys assay (slope = 1.10, 95% CI: 1.09 to 1.12). The average of the difference between the two assays was 2.7 pmol/l. The 95% limits of agreement were −11.7 to 6.3. Overall 253 (29.3%) women would have received an inappropriate follitropin delta dose if the Beckman Coulter Access assay was used. Specifically, a substantial proportion of women (ranging from 49% to 90% depending on the AMH category) would receive a lower dose of follitropin delta based on the Access AMH assay. Up to 10% (ranging from 2.5% to 10%) of women with high ovarian reserve would have been misclassified to a greater dose of follitropin delta based on the Access AMH assay. LIMITATIONS REASONS FOR CAUTION We compared the values of the two principal automated assays, extrapolation of our findings to other automated AMH assays would require similar comprehensive examination. WIDER IMPLICATIONS OF THE FINDINGS An international standard for the calibration of the automated AMH assays is warranted to facilitate efficient use of AMH as a companion diagnostic. The variable calibration of alternative automated AMH assays may adversely impact on the performance of the follitropin delta dosing algorithm. STUDY FUNDING/COMPETING INTEREST(S) No formal funding has been received for this study. SI is funded by a UK Medical Research Council skills development fellowship (MR/N015177/1). SMN has received speakers fees, travel to meetings and participated in advisory Boards for Beckman Coulter, IBSA, Ferring Pharmaecuticals, Finox, Merck Serono, Merck and Roche Diagnostics. SMN has received research support from Ansh laboratories, Beckman Coulter, Ferring Pharmaceuticals and Roche Diagnostics

    The Process gamma* + p -> eta_c + X: A Test for the Perturbative QCD Odderon

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    The rates of inclusive photo- and electroproduction of the eta_c meson: gamma* + p -> eta_c + X are calculated in the triple Regge region, integrated over the diffractive mass X. For the Regge exchanges we use the hard Pomeron and Odderon, both being calculated in the framework of perturbative QCD. The integrated cross-section depends upon the coupling of the BFKL pomeron to two C=1C=-1 odderons, and it is found to be of the order 60 pb for photoproduction and 1.5 pb at Q^2=25 GeV^2.Comment: 19 pages, latex, 7 eps figure
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