451 research outputs found

    Hepatic Sarcoidosis Presenting as Portal Hypertension and Liver Cirrhosis: Case Report and Review of the Literature

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    Systemic sarcoidosis is a disease of unknown etiology, with the liver being the third most commonly affected organ. Most cases of hepatic sarcoidosis are not clinically apparent, but a few can progress to liver cirrhosis, portal hypertension and ultimately liver failure. The diagnosis of hepatic sarcoidosis is difficult, considering that no single laboratory test or radiographic finding can definitively diagnose this systemic disease. Diagnosis of hepatic sarcoidosis relies heavily on histopathologic evaluation of two or more organs, a diagnostic modality that is invasive and may not be applicable to all patients. The treatment of hepatic sarcoidosis is challenging, with no large randomized controlled trials done to date. Physicians must be aware of the complications of hepatic sarcoidosis, and must include the same in the differential diagnosis of liver cirrhosis. We present a case of hepatic sarcoidosis complicated by portal hypertension and liver cirrhosis

    Season of birth, clinical manifestations and Dexamethasone Suppression Test in unipolar major depression

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    <p>Abstract</p> <p>Background</p> <p>Reports in the literature suggest that the season of birth might constitute a risk factor for the development of a major psychiatric disorder, possibly because of the effect environmental factors have during the second trimester of gestation. The aim of the current paper was to study the possible relationship of the season of birth and current clinical symptoms in unipolar major depression.</p> <p>Methods</p> <p>The study sample included 45 DSM-IV major depressive patients and 90 matched controls. The SCAN v. 2.0, Hamilton Depression Rating Scale (HDRS) and Hamilton Anxiety Scale (HAS) were used to assess symptomatology, and the 1 mg Dexamethasone Suppression Test (DST) was used to subcategorize patients.</p> <p>Results</p> <p>Depressed patients as a whole did not show differences in birth season from controls. However, those patients born during the spring manifested higher HDRS while those born during the summer manifested the lowest HAS scores. DST non-suppressors were almost exclusively (90%) likely to be born during autumn and winter. No effect from the season of birth was found concerning the current severity of suicidal ideation or attempts.</p> <p>Discussion</p> <p>The current study is the first in this area of research using modern and rigid diagnostic methodology and a biological marker (DST) to categorize patients. Its disadvantages are the lack of data concerning DST in controls and a relatively small size of patient sample. The results confirm the effect of seasonality of birth on patients suffering from specific types of depression.</p

    Clinical and Non-Clinical Aspects of Distal Radioulnar Joint Instability

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    Untreated distal radioulnar joint (DRUJ) injuries can give rise to long lasting complaints. Although common, diagnosis and treatment of DRUJ injuries remains a challenge. The articulating anatomy of the distal radius and ulna, among others, enables an extensive range of forearm pronosupination movements. Stabilization of this joint is provided by both intrinsic and extrinsic stabilizers and the joint capsule. These structures transmit the load and prevent the DRUJ from luxation during movement. Several clinical tests have been suggested to determine static or dynamic DRUJ stability, but their predictive value is unclear. Radiologic evaluation of DRUJ instability begins with conventional radiographs in anterioposterior and true lateral view. If not conclusive, CT-scan seems to be the best additional modality to evaluate the osseous structures. MRI has proven to be more sensitive and specific for TFCC tears, potentially causing DRUJ instability. DRUJ instability may remain asymptomatic. Symptomatic DRUJ injuries treatment can be conservative or operative. Operative treatment should consist of restoration of osseous and ligamenteous anatomy. If not successful, salvage procedures can be performed to regain stability

    Gravitational Radiation from Post-Newtonian Sources and Inspiralling Compact Binaries

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    The article reviews the current status of a theoretical approach to the problem of the emission of gravitational waves by isolated systems in the context of general relativity. Part A of the article deals with general post-Newtonian sources. The exterior field of the source is investigated by means of a combination of analytic post-Minkowskian and multipolar approximations. The physical observables in the far-zone of the source are described by a specific set of radiative multipole moments. By matching the exterior solution to the metric of the post-Newtonian source in the near-zone we obtain the explicit expressions of the source multipole moments. The relationships between the radiative and source moments involve many non-linear multipole interactions, among them those associated with the tails (and tails-of-tails) of gravitational waves. Part B of the article is devoted to the application to compact binary systems. We present the equations of binary motion, and the associated Lagrangian and Hamiltonian, at the third post-Newtonian (3PN) order beyond the Newtonian acceleration. The gravitational-wave energy flux, taking consistently into account the relativistic corrections in the binary moments as well as the various tail effects, is derived through 3.5PN order with respect to the quadrupole formalism. The binary's orbital phase, whose prior knowledge is crucial for searching and analyzing the signals from inspiralling compact binaries, is deduced from an energy balance argument.Comment: 109 pages, 1 figure; this version is an update of the Living Review article originally published in 2002; available on-line at http://www.livingreviews.org

    Physics, Astrophysics and Cosmology with Gravitational Waves

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    Gravitational wave detectors are already operating at interesting sensitivity levels, and they have an upgrade path that should result in secure detections by 2014. We review the physics of gravitational waves, how they interact with detectors (bars and interferometers), and how these detectors operate. We study the most likely sources of gravitational waves and review the data analysis methods that are used to extract their signals from detector noise. Then we consider the consequences of gravitational wave detections and observations for physics, astrophysics, and cosmology.Comment: 137 pages, 16 figures, Published version <http://www.livingreviews.org/lrr-2009-2

    Characterization of human and rodent native and recombinant adenosine A2B receptors by radioligand binding studies

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    Adenosine A2B receptors of native human and rodent cell lines were investigated using [3H]PSB-298 [(8-{4-[2-(2-hydroxyethylamino)-2-oxoethoxy]phenyl}-1-propylxanthine] in radioligand binding studies. [3H]PSB-298 showed saturable and reversible binding. It exhibited a KD value of 60 ± 1 nM and limited capacity (Bmax = 3.511 fmol per milligram protein) at recombinant human adenosine A2B receptors expressed in human embryonic kidney cells (HEK-293). The addition of sodium chloride (100 mM) led to a threefold increase in the number of binding sites recognized by the radioligand. The curve of the agonist 5′-N-ethylcarboxamidoadenosine (NECA) was shifted to the right in the presence of NaCl, while the curve of the antagonist PSB-298 was shifted to the left, indicating that PSB-298 may be an inverse agonist at A2B receptors. Adenosine A2B receptors were shown to be the major adenosine A2 receptor subtype on the mouse neuroblastoma x rat glioma hybrid cell line NG108-15 cells. Binding studies at rat INS-1 cells (insulin secreting cell line) demonstrated that [3H]PSB-298 is a selective radioligand for adenosine A2B binding sites in this cell line

    Hypersensitive Response-Like Reaction Is Associated with Hybrid Necrosis in Interspecific Crosses between Tetraploid Wheat and Aegilops tauschii Coss

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    BACKGROUND: Hybrid speciation is classified into homoploid and polyploid based on ploidy level. Common wheat is an allohexaploid species that originated from a naturally occurring interploidy cross between tetraploid wheat and diploid wild wheat Aegilops tauschii Coss. Aegilops tauschii provides wide naturally occurring genetic variation. Sometimes its triploid hybrids with tetraploid wheat show the following four types of hybrid growth abnormalities: types II and III hybrid necrosis, hybrid chlorosis, and severe growth abortion. The growth abnormalities in the triploid hybrids could act as postzygotic hybridization barriers to prevent formation of hexaploid wheat. METHODOLOGY/PRINCIPAL FINDINGS: Here, we report on the geographical and phylogenetic distribution of Ae. tauschii accessions inducing the hybrid growth abnormalities and showed that they are widely distributed across growth habitats in Ae. tauschii. Molecular and cytological characterization of the type III necrosis phenotype was performed. The hybrid abnormality causing accessions were widely distributed across growth habitats in Ae. tauschii. Transcriptome analysis showed that a number of defense-related genes such as pathogenesis-related genes were highly up-regulated in the type III necrosis lines. Transmission electron microscope observation revealed that cell death occurred accompanied by generation of reactive oxygen species in leaves undergoing type III necrosis. The reduction of photosynthetic activity occurred prior to the appearance of necrotic symptoms on the leaves exhibiting hybrid necrosis. CONCLUSIONS/SIGNIFICANCE: Taking these results together strongly suggests that an autoimmune response might be triggered by intergenomic incompatibility between the tetraploid wheat and Ae. tauschii genomes in type III necrosis, and that genetically programmed cell death could be regarded as a hypersensitive response-like cell death similar to that observed in Arabidopsis intraspecific and Nicotiana interspecific hybrids. Only Ae. tauschii accessions without such inhibiting factors could be candidates for the D-genome donor for the present hexaploid wheat

    Ulnar-sided wrist pain. II. Clinical imaging and treatment

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    Pain at the ulnar aspect of the wrist is a diagnostic challenge for hand surgeons and radiologists due to the small and complex anatomical structures involved. In this article, imaging modalities including radiography, arthrography, ultrasound (US), computed tomography (CT), CT arthrography, magnetic resonance (MR) imaging, and MR arthrography are compared with regard to differential diagnosis. Clinical imaging findings are reviewed for a more comprehensive understanding of this disorder. Treatments for the common diseases that cause the ulnar-sided wrist pain including extensor carpi ulnaris (ECU) tendonitis, flexor carpi ulnaris (FCU) tendonitis, pisotriquetral arthritis, triangular fibrocartilage complex (TFCC) lesions, ulnar impaction, lunotriquetral (LT) instability, and distal radioulnar joint (DRUJ) instability are reviewed

    Exploring new physics frontiers through numerical relativity

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    The demand to obtain answers to highly complex problems within strong-field gravity has been met with significant progress in the numerical solution of Einstein's equations - along with some spectacular results - in various setups. We review techniques for solving Einstein's equations in generic spacetimes, focusing on fully nonlinear evolutions but also on how to benchmark those results with perturbative approaches. The results address problems in high-energy physics, holography, mathematical physics, fundamental physics, astrophysics and cosmology

    The Confrontation between General Relativity and Experiment

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    The status of experimental tests of general relativity and of theoretical frameworks for analysing them is reviewed. Einstein's equivalence principle (EEP) is well supported by experiments such as the Eotvos experiment, tests of special relativity, and the gravitational redshift experiment. Future tests of EEP and of the inverse square law are searching for new interactions arising from unification or quantum gravity. Tests of general relativity at the post-Newtonian level have reached high precision, including the light deflection, the Shapiro time delay, the perihelion advance of Mercury, and the Nordtvedt effect in lunar motion. Gravitational-wave damping has been detected in an amount that agrees with general relativity to better than half a percent using the Hulse-Taylor binary pulsar, and other binary pulsar systems have yielded other tests, especially of strong-field effects. When direct observation of gravitational radiation from astrophysical sources begins, new tests of general relativity will be possible.Comment: 89 pages, 8 figures; an update of the Living Review article originally published in 2001; final published version incorporating referees' suggestion
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