Thromboelastography in mild, chronic liver disease: challenging conventional coagulation tests preceding liver biopsy

Patients presenting for liver biopsy may have a deficiency of the synthetic function of the liver. They commonly undergo testing of their INR, which is used to decide if there may be a bleeding risk and if that needs to be mitigated by the administration of clotting factors. This study aimed to observe the coagulation profile of these patients via a thromboelastogram (TEG), and to search for a relationship between the traditionally used INR and the R-time of the TEG.A prospective observational pilot study was conducted over a seven-month period. An FBC, INR and kaolin activated thromboelastogram were performed on each patient. Spearman’s correlation coefficient was used to determine the relationship between the INR and the R-time of the TEG.The TEG was performed on 28 participants. Two were excluded from analysis as they had received Vitamin K. Twenty-three patients (88%) had abnormal liver function tests. Drug or toxins were responsible for liver injury in 15 (58%) participants. Twenty-two (85%) had normal platelet counts. Three (12%) were found to be hypocoagulable, four (15%) were hypercoagulable, and the remaining 19 (73%) had normal thromboelastography. The three (12%) participants who were hypocoagulable had a normal platelet count. No association was found between INR and the R-time of TEG (Spearman’s rho −0.20, p = 0.34). In the two participants (8%) with a raised INR (1.26 and 1.7 respectively), the TEG suggested a normal or hypercoagulable status.This study revealed that most patients with mild, chronic liver disease presenting for liver biopsy have a normal TEG. There was no association between INR and the R-time of the TEG. This suggests that INR may not be a reliable test of coagulation status in these patients with mild chronic liver disease, which is contrary to the traditional practice of using INR to infer coagulation status. Further larger studies looking specifically at patients with drug and toxin induced liver injury are warranted.Keywords: international normalised ratio, liver biopsy, liver disease, thromboelastography, viscoelastic coagulation testin

Nuclear Spin-Isospin Correlations, Parity Violation, and the fπf_\pi Problem

The strong interaction effects of isospin- and spin-dependent nucleon-nucleon correlations observed in many-body calculations are interpreted in terms of a one-pion exchange mechanism. Including such effects in computations of nuclear parity violating effects leads to enhancements of about 10%. A larger effect arises from the one-boson exchange nature of the parity non-conserving nucleon- nucleon interaction, which depends on both weak and strong meson-nucleon coupling constants. Using values of the latter that are constrained by nucleon-nucleon phase shifts leads to enhancements of parity violation by factors close to two. Thus much of previously noticed discrepancies between weak coupling constants extracted from different experiments can be removed.Comment: 8 pages 2 figures there should have been two figures in v

Sexually Transmitted Diseases and Human Immunodeficiency Virus Infection: Cause, Effect, or Both?

The infectiousness of the index case and the susceptibility of the exposed host mediate the sexual transmission of human immunodeficiency virus (HIV). Infectiousness of the index case is determined by the inoculum of HIV and viral factors that favor transmission. Persons with primary infection, late stage disease, or low CD4 counts appear to transmit HIV with greater efficiency, presumably through increased viral burden in genital secretions. Susceptibility to HIV infection is determined by hereditary resistance factors, acquired immunity, site of exposure to the virus, and integrity of local barriers (e.g., vaginal epithelium). Hereditary resistance factors, such as cell surface receptors required for transmission of some viral variants, have been identified in studies of exposed, but uninfected persons. Acquired immunity, including protective cytotoxic T lymphocyte or antibody responses, may be important in persons repeatedly exposed to HIV who do not become infected. Sexual practices also affect susceptibility, with receptive anal intercourse having the highest risk, followed by vaginal intercourse and fellatio. Similarly, women are more susceptible to infection than men, through vaginal intercourse. In general, any factor affecting excretion of HIV or the number of receptive cells can be expected to affect the efficiency of transmission

Exact Solutions for Matter-Enhanced Neutrino Oscillations

The analogy between supersymmetric quantum mechanics and matter-enhanced neutrino oscillations is exploited to obtain exact solutions for a class of electron density profiles. This integrability condition is analogous to the shape-invariance in supersymmetric quantum mechanics. This method seems to be the most direct way to obtain the exact survival probabilities for a number of density profiles of interest, such as linear and exponential density profiles. The resulting neutrino amplitudes can also be utilized as comparison amplitudes for the uniform semiclassical treatment of neutrino propagation in arbitrary electron density profiles.Comment: Submitted to Physical Review D. Latex file, 8 pages. This paper is also available at http://nucth.physics.wisc.edu/preprints

The awareness framework: A novel approach for understanding HIV testing and disclosure in HIV-discordant dyads

HIV testing and counseling (HTC) is rapidly being brought to scale in sub-Saharan Africa. Scale-up has been driven primarily by the goal of linking HIV-infected persons to treatment. But what impact will HTC scale-up have on HIV prevention, especially as new biomedical HIV prevention interventions are introduced

Heisenberg exchange enhancement by orbital relaxation in cuprate compounds

We calculate the Heisenberg exchange J in the quasi-2D antiferromagnetic cuprates La2CuO4, YBa2Cu3O6, Nd2CuO4 and Sr2CuO2Cl2. We apply all-electron (MC)SCF and non-orthogonal CI calculations to [Cu2O11]18-, [Cu2O9]14-, [Cu2O7]10- and [Cu2O7Cl4]14- clusters in a model charge embedding. The (MC)SCF triplet and singlet ground states are well characterized by Cu2+ (dx2-y2) and O2-. The antiferromagnetic exchange is strongly enhanced by admixing relaxed (MC)SCF triplet and singlet excited states, in which a single electron is transferred from the central O ion to Cu. We ascribe this effect to orbital relaxation in the charge transfer component of the wave function. Close agreement with experiment is obtained.Comment: publishe

HIV Care Initiation Delay among Rural Residents in the Southeastern United States, 1996 to 2012

Background: Delaying HIV care initiation may lead to greater morbidity, mortality, and further HIV transmission. Rural residence may be associated with delayed diagnosis and linkage to care, with negative clinical outcomes. Objective: To examine the association between rural patient residence and CD4 cell count at HIV care initiation in a large HIV clinical cohort in the Southeastern United States. Methods: We included HIV-infected patients who initiated care between 1996 and 2012 with a geocodable address and no previous history of HIV clinical care. Patient residence was categorized as urban or rural using United States Department of Agriculture Rural Urban Commuting Area codes. Multivariable linear regression models were fit to estimate the association between patient residence and CD4 cell count at HIV care initiation. Results: Among 1396 patients who met study inclusion criteria, 988 had a geocodable address. Overall, 35% of patients resided in rural areas and presented to HIV care with a mean CD4 cell count of 351 cells/mm 3 (SD, 290). Care initiation mean CD4 cell counts increased from 329 cells/mm 3 (SD, 283) in 1996-2003 to 391 cells/mm 3 (SD, 292) in 2008-2012 (P = 0.006). Rural in comparison with urban patients presented with lower CD4 cell counts with an unadjusted and adjusted mean difference of -48 cells/mm 3 [95% confidence interval, -86 to -10) and -37 cells/mm 3 (95% confidence interval: -73 to -2), respectively, consistently observed across calendar years. Conclusions: HIV care initiation at low CD4 cell counts was common in this Southeastern US cohort and more common among rural area residents

New calculations of the PNC Matrix Element for the JπTJ^{\pi}T 0+1,0−1^{+}1,0^{-}1 doublet in 14^{14}N

A new calculation of the predominantly isoscalar PNC matrix element between the $J^{\pi}T$ $0^{+}1,0^{-}1$ (E$_{x} \approx$ 8.7 MeV) states in $^{14}$N has been carried out in a (0+1+2+3+4)$\hbar \omega$ model space with the Warburton-Brown interaction. The magnitude of the PNC matrix element of 0.22 to 0.34 eV obtained with the DDH PNC interaction is substantially suppressed compared with previous calculations in smaller model spaces but shows agreement with the preliminary Seattle experimental data. The calculated sign is opposite to that obtained experimentally, and the implications of this are discussed.Comment: REVTEX, 28 page