Precipitation hardening of a Mg - 3.5 wt. % Th - 1. wt. % Mn alloy

The precipitation process in a Mg - 3.5 wt. % Th - 1. wt. % Mn alloy during aging at 260⁰, 350⁰ and 400⁰C was determined principally by transmission electron microscopy. At 350⁰ and 400⁰C, general precipitation of the equilibrium Mg₄Th phase moderately hardens the alloy. No transition lattice of this phase was seen. The Mg₄Th precipitate forms initially as disc shaped plates parallel either to the prism or basal plane of the matrix...During prolonged aging at 400⁰C the plates lengthen into long laths on either of the above planes in the close packed direction...At 260⁰C an unidentified G. P. zone appearing precipitate forms --Abstract, page ii

Combining subspace approach and short time Fourier analysis for locating structural damage storeys

This study proposes a novel and efficient approach for locating the floors of a building whose stiffnesses change after being subject to a strong earthquake. The floors that may be damaged are determined by comparing the unitary stiffness matrix in different stages in the life cycle of a building. To evaluate the coefficient matrices of a state-space model, the proposed procedure applies a subspace approach in conjunction with the short time Fourier analysis. The dynamic characteristics of a structure are determined from the coefficient matrices. Next, the unitary stiffness matrix is constructed by identifying natural frequencies and mode shapes. The effectiveness of the proposed procedure is verified using the measured earthquake acceleration responses of a three-storey structure that sustains damage on one or two floors and an eight-storey steel frame under a 200 Gal and a 1200 Gal earthquake, such as the Chi-chi earthquake that shook Taiwan on September 1999. The proposed scheme is compared to mode shape based approaches in identifying damaged floors, and is demonstrated to be superior to both MAC (Modal Assurance Criterion) and COMAC (Coordinate Modal Assurance Criterion)

Hepatic hydrothorax after blunt chest trauma

AbstractWe report a successful treatment result in a rare case of hepatitis C virus-related cirrhosis, who had sustained hydrothorax after blunt thoracoabdominal trauma. This was a female patient with liver cirrhosis, Child–Turcotte–Pugh class A, without ascites before injury. She sustained blunt thoracoabdominal trauma with a left clavicle fracture dislocation and right rib fractures. There was no hemopneumothorax at initial presentation. However, dyspnea and right pleural effusion developed gradually. We inserted a chest tube to relieve the patient's symptoms, and the daily drainage amount remained consistent. Hepatic hydrothorax was confirmed by the intraperitoneal injection of radioisotope 99mTc-sulfur colloid that demonstrated one-way transdiaphragmatic flow of fluid from the peritoneal cavity to pleural cavities. Finally, the hydrothorax was treated successfully by minocycline-induced pleural symphysis. To the best of our knowledge, this is the first case of hepatic hydrothorax developed after thoracoabdominal trauma

Phosphorylation at Ser473 regulates heterochromatin protein 1 binding and corepressor function of TIF1beta/KAP1

<p>Abstract</p> <p>Background</p> <p>As an epigenetic regulator, the transcriptional intermediary factor 1β (TIF1β)/KAP1/TRIM28) has been linked to gene expression and chromatin remodeling at specific loci by association with members of the heterochromatin protein 1 (HP1) family and various other chromatin factors. The interaction between TIF1β and HP1 is crucial for heterochromatin formation and maintenance. The HP1-box, PXVXL, of TIF1β is responsible for its interaction with HP1. However, the underlying mechanism of how the interaction is regulated remains poorly understood.</p> <p>Results</p> <p>This work demonstrates that TIF1β is phosphorylated on Ser473, the alteration of which is dynamically associated with cell cycle progression and functionally linked to transcriptional regulation. Phosphorylation of TIF1β/Ser473 coincides with the induction of cell cycle gene <it>cyclin A2 </it>at the S-phase. Interestingly, chromatin immunoprecipitation demonstrated that the promoter of <it>cyclin A2 </it>gene is occupied by TIF1β and that such occupancy is inversely correlated with Ser473 phosphorylation. Additionally, when HP1β was co-expressed with TIF1β/S473A, but not TIF1β/S473E, the colocalization of TIF1β/S473A and HP1β to the promoters of <it>Cdc2 </it>and <it>Cdc25A </it>was enhanced. Non-phosphorylated TIF1β/Ser473 allowed greater TIF1β association with the regulatory regions and the consequent repression of these genes. Consistent with possible inhibition of TIF1β's corepressor function, the phosphorylation of the Ser473 residue, which is located near the HP1-interacting PXVXL motif, compromised the formation of TIF1β-HP1 complex. Finally, we found that the phosphorylation of TIF1β/Ser473 is mediated by the PKCδ pathway and is closely linked to cell proliferation.</p> <p>Conclusion</p> <p>The modulation of HP1β-TIF1β interaction through the phosphorylation/de-phosphorylation of TIF1β/Ser473 may constitute a molecular switch that regulates the expression of particular genes. Higher levels of phosphorylated TIF1β/Ser473 may be associated with the expression of key regulatory genes for cell cycle progression and the proliferation of cells.</p

Spleen artery embolization increases the success of nonoperative management following blunt splenic injury

AbstractBackgroundSpleen artery embolization (SAE) may increase the success rate of nonoperative management (NOM). The present study investigated the clinical outcome after the installation of SAE in the management of blunt splenic injury.MethodsA retrospective review of hospital records was performed to enroll patients with blunt injury of the spleen. Demographic data and information about the injury severity score, organ injury scale, hospitalization days, management and final outcomes were evaluated. Patients were separated into early and late groups according to the year that SAE was selectively used (2003–2004 and 2005–2008).ResultsSix of eleven (55%) patients in the early group were successfully managed without surgery for blunt splenic injury, whereas all of the 38 patients (100%) in the late group were successfully managed without surgery. Eleven patients (11 of 38; 28.9%) received SAE in the late group. The rate of NOM increased from 55% in the early group to 100% in the late group (p < 0.001). Both early and late groups had similar injury severity score, length of hospitalization, blood transfusion, and complications, and there was no mortality.ConclusionPerformance of SAE for the patients with blunt splenic injury could increase the successful rate of NOM significantly and safely. An algorithm including the angioembolization might be beneficial in the management of patients with blunt spleen trauma

Topical application of marine briarane-type diterpenes effectively inhibits 12-O-tetradecanoylphorbol-13-acetate-induced inflammation and dermatitis in murine skin

<p>Abstract</p> <p>Background</p> <p>Skin is the largest organ in the body, and is directly exposed to extrinsic assaults. As such, the skin plays a central role in host defense and the cutaneous immune system is able to elicit specific local inflammatory and systemic immune responses against harmful stimuli. 12-O-tetradecanoylphorbol-13-acetate (TPA) can stimulate acute and chronic inflammation and tumor promotion in skin. TPA-induced dermatitis is thus a useful <it>in vivo </it>pharmacological platform for drug discovery. In this study, the inhibitory effect of briarane-type diterpenes (BrDs) from marine coral <it>Briareum excavatum </it>on TPA-induced dermatitis and dendritic cell (DC) function was explored.</p> <p>Methods</p> <p>Evans blue dye exudation was used to determine vascular permeability. H&E-stained skin section was used to determine the formation of edema in mouse abdominal skin. We also used immunohistochemistry staining and western blot assays to evaluate the activation of specific inflammation makers and key mediators of signaling pathway in the mouse skin. Furthermore, mouse bone marrow DCs were used to determine the relationship between the chemical structure of BrDs and their regulation of DC function.</p> <p>Results</p> <p>BrD1 remarkably suppressed TPA-induced vascular permeability and edema in skin. At the biochemical level, BrD1 inhibited TPA-induced expression of cyclooxygenase-2, inducible nitric oxide synthase and matrix metalloproteinase-9, the key indicators of cutaneous inflammation. This inhibition was apparently mediated by interference with the Akt/NF-κB-mediated signaling network. BrD1 also inhibited TNF-α and IL-6 expression in LPS-stimulated BMDCs. The 8, 17-epoxide of BrDs played a crucial role in the inhibition of IL-6 expression, and replacement of the C-12 hydroxyl group with longer esters in BrDs gradually decreased this inhibitory activity.</p> <p>Conclusions</p> <p>Our results suggest that BrDs warrant further investigation as natural immunomodulatory agents for control of inflammatory skin diseases.</p

Multi-parametric neuroimaging evaluation of cerebrotendinous xanthomatosis and its correlation with neuropsychological presentations

<p>Abstract</p> <p>Background</p> <p>Cerebrotendinous xanthomatosis (CTX) is a rare genetic disorder. Recent studies show that brain damage in CTX patients extends beyond the abnormalities observed on conventional magnetic resonance imaging (MRI). We studied the MRI and ^{99 m}Tc-ethyl cysteinate dimer single photon emission computed tomography (SPECT) findings of CTX patients and made a correlation with the neuropsychological presentations.</p> <p>Methods</p> <p>Diffusion tensor imaging (DTI) and 3D T1-weighted images of five CTX patients were compared with 15 age-matched controls. Voxel-based morphometry (VBM) was use to delineate gray matter (GM) and white matter (WM) volume loss. Fractional anisotropy (FA), mean diffusivity (MD), and eigenvalues derived from DTI were used to detect WM changes and correlate with neuropsychological results. SPECT functional studies were used to correlate with GM changes.</p> <p>Results</p> <p>Cognitive results showed that aside from moderate mental retardation, the patient group performed worse in all cognitive domains. Despite the extensive GM atrophy pattern, the cerebellum, peri-Sylvian regions and parietal-occipital regions were correlated with SPECT results. WM atrophy located in the peri-dentate and left cerebral peduncle areas corresponded with changes in diffusion measures, while axial and radial diffusivity suggested both demyelinating and axonal changes. Changes in FA and MD were preceded by VBM in the corpus callosum and corona radiata. Cognitive results correlated with FA changes.</p> <p>Conclusion</p> <p>In CTX, GM atrophy affected the perfusion patterns. Changes in WM included atrophy, and axonal changes with demyelination. Disconnection of major fiber tracts among different cortical regions may contribute to cognitive impairment.</p