bluuebunny/crossref_metadata_2025_split huggingface dataset:
Insights into the structure and activity of prototype foamy virus RNase H
Authors: Leo Berit , Hartl Maximilian J , Schweimer Kristian , Mayr Florian , Wöhrl Birgitta M 
Published: February 2012

Abstract

Background
RNase H is an endonuclease that hydrolyzes the RNA strand in RNA/DNA hybrids. Retroviral reverse transcriptases harbor a C-terminal RNase H domain whose activity is essential for viral replication. The RNase H degrades the viral genomic RNA after the first DNA strand is synthesized. Here, we report the biophysical and enzymatic properties of the RNase H domain of prototype foamy virus (PFV) as an independently purified protein. Sequence comparisons with other retroviral RNases H indicated that PFV RNase H harbors a basic protrusion, including a basic loop and the so-called C-helix, which was suggested to be important for activity and substrate binding and is absent in the RNase H domain of human immunodeficiency virus. So far, no structure of a retroviral RNase H containing a C-helix is available.

Results
RNase H activity assays demonstrate that the PFV RNase H domain is active, although its activity is about 200-fold reduced as compared to the full length protease-reverse transcriptase enzyme. Fluorescence equilibrium titrations with an RNA/DNA substrate revealed a KD for the RNase H domain in the low micromolar range which is about 4000-fold higher than that of the full-length protease-reverse transcriptase enzyme. Analysis of the RNase H cleavage pattern using a [32P]-labeled substrate indicates that the independent RNase H domain cleaves the substrate non-specifically. The purified RNase H domain exhibits a well defined three-dimensional structure in solution which is stabilized in the presence of Mg2+ ions.

Conclusions
Our data demonstrate that the independent PFV RNase H domain is structured and active. The presence of the C-helix in PFV RNase H could be confirmed by assigning the protein backbone and calculating the chemical shift index using NMR spectroscopy.
Trends in national suicide rates for Scotland and for England & Wales, 1960–2008
Authors: Mok Pearl L. H. , Kapur Navneet , Windfuhr Kirsten , Leyland Alastair H. , Appleby Louis , Platt Stephen , Webb Roger T. 
Published: February 2012

BackgroundSuicide rates in Scotland have increased markedly relative to those in England in recent decades.AimsTo compare changing patterns of suicide risk in Scotland with those in England & Wales, 1960–2008.MethodFor Scotland and for England & Wales separately, we obtained national data on suicide counts and population estimates. Gender-specific, directly age-standardised rates were calculated.ResultsWe identified three distinct temporal phases: 1960–1967, when suicide rates in England & Wales were initially higher than in Scotland, but then converged; 1968–1991, when male suicide rates in Scotland rose slightly faster than in England & Wales; and 1992–2008, when there was a marked divergence in national trends. Much of the recent divergence in rates is attributable to the rise in suicide among young men and deaths by hanging in Scotland. Introduction of the ‘undetermined intent’ category in 1968 had a significant impact on suicide statistics across Great Britain, but especially so in Scotland.ConclusionsDifferences in temporal patterns in suicide risk between the countries are complex. Reversal of the divergent trends may require a change in the perception of hanging as a ‘painless' method of suicide.
Alcohol use disorders and the course of depressive and anxiety disorders
Authors: Boschloo Lynn , Vogelzangs Nicole , van den Brink Wim , Smit Johannes H. , Veltman Dick J. , Beekman Aartjan T. F. , Penninx Brenda W. J. H. 
Published: February 2012

BackgroundInconsistent findings have been reported on the role of comorbid alcohol use disorders as risk factors for a persistent course of depressive and anxiety disorders.AimsTo determine whether the course of depressive and/or anxiety disorders is conditional on the type (abuse or dependence) or severity of comorbid alcohol use disorders.MethodIn a large sample of participants with current depression and/or anxiety (n= 1369) we examined whether the presence and severity of DSM-IV alcohol abuse or alcohol dependence predicted the 2-year course of depressive and/or anxiety disorders.ResultsThe persistence of depressive and/or anxiety disorders at the 2-year follow-up was significantly higher in those with remitted or current alcohol dependence (persistence 62% and 67% respectively), but not in those with remitted or current alcohol abuse (persistence 51% and 46% respectively), compared with no lifetime alcohol use disorder (persistence 53%). Severe (meeting six or seven diagnostic criteria) but not moderate (meeting three to five criteria) current dependence was a significant predictor as 95% of those in the former group still had a depressive and/or anxiety disorder at follow-up. This association remained significant after adjustment for severity of depression and anxiety, psychosocial factors and treatment factors.ConclusionsAlcohol dependence, especially severe current dependence, is a risk factor for an unfavourable course of depressive and/or anxiety disorders, whereas alcohol abuse is not.
Nuclear Smad7 Overexpressed in Mesenchymal Cells Acts as a Transcriptional Corepressor by Interacting with HDAC-1 and E2F to Regulate Cell Cycle
Authors: Emori Takashi , Kitamura Koki , Okazaki Kenji 
Published: February 2012

Summary
Smad family proteins are essential intracellular mediators that regulate transforming growth factor-β (TGF-β) ligand signaling. In response to diverse stimuli, Smad7 is rapidly expressed and acts as a cytoplasmic inhibitor that selectively interferes with signals elicited from TGF-β family receptors. In addition, earlier works have indicated that retrovirally transduced Smad7 induces long-lasting cell proliferation arrest in a variety of mesenchymal cells through down-regulation of G1 cyclins. However, the molecular mechanisms underlying the cytostatic effects of Smad7 remain unknown. We show here that Smad7 can form a complex with endogenous histone deacetylase proteins HDAC-1 and HDAC-3 in NIH 3T3 mouse fibroblast cells. By contrast, forced expression of a dominant-negative variant of HDAC-1 efficiently protected cells against Smad7 proliferation inhibition, suggesting that Smad7 depends on the deacetylase activity of its associated HDAC-1 to arrest the cell cycle. Furthermore, Smad7 caused HDAC-1 bind to E2F-1 to form a ternary complex on chromosomal DNA containing an E2F-binding motif and leading to repression in the activity of the E2F target genes. Smad7 mutations that prevented its binding to either HDAC-1 or E2F-1 resulted in a significant decrease in Smad7-mediated inhibition of cell proliferation. The present results strongly suggest that nuclear Smad7 is a transcriptional corepressor for E2F, providing a molecular basis for the Smad7-induced arrest of the cell cycle.
Toward an Atomic-Level Understanding of Size-Specific Properties of Protected and Stabilized Gold Clusters
Authors: Tsukuda Tatsuya 
Published: February 2012

Abstract
Metal clusters consisting of fewer than 100 atoms (diameter &lt;2 nm) are highly promising as a new class of building units for functional materials because of their novel and size-dependent properties. Nevertheless, basic and applied studies of metals clusters have been hampered by the lack of specific guidelines for design and precise synthetic methods. This account surveys recent investigations of gold clusters focusing on our effort toward an atomic-level understanding and control of their size-specific properties. We have developed a size-controlled method for synthesizing gold clusters protected by ligands, stabilized by polymers, and supported on solids. Remarkable size-effects on stabilities and various properties including catalysis were observed. Their mechanisms are discussed based on fundamental knowledge of bare gold clusters in the gas phase.
Management of tibial bone defects with metal augmentation in primary total knee replacement
Authors: Lee J. K. , Choi C. H. 
Published: February 2012

Bone defects are occasionally encountered during primary total knee replacement (TKR) and cause difficulty in establishing a stable well-aligned bone-implant interface. Between March 1999 and November 2005, 59 knees in 43 patients underwent primary TKR with a metal block augmentation for tibial bone deficiency. In all, six patients (eight knees) died less than four years post-operatively, and four patients (five knees) were lost to follow-up leaving 46 knees in 33 patients available for review at a mean of 78.6 months (62 to 129). The clinical results obtained, including range of movement, American Knee Society and Oxford knee scores, and the Western Ontario and McMaster Universities osteoarthritis index, were good to excellent, with no failures. Radiolucent lines at the block-cement-bone interface were noted in five knees (11%) during the first post-operative year, but these did not progress.Modular rectangular metal augmentation for tibial bone deficiency is a useful option. No deterioration of the block-prosthesis or block-cement-bone interface was seen at minimum of five years follow-up.
Safety and outcome of surgical debridement of insertional Achilles tendinopathy using a transverse (Cincinnati) incision
Authors: Maffulli N. , Del Buono A. , Testa V. , Capasso G. , Oliva F. , Denaro V. 
Published: February 2012

This is a prospective analysis on 30 physically active individuals with a mean age of 48.9 years (35 to 64) with chronic insertional tendinopathy of the tendo Achillis. Using a transverse incision, the tendon was debrided and an osteotomy of the posterosuperior corner of the calcaneus was performed in all patients. At a minimum post-operative follow-up of three years, the Victorian Institute of Sports Assessment scale – Achilles tendon scores were significantly improved compared to the baseline status. In two patients a superficial infection of the wound developed which resolved on antibiotics. There were no other wound complications, no nerve related complications, and no secondary avulsions of the tendo Achillis. In all, 26 patients had returned to their pre-injury level of activity and the remaining four modified their sporting activity. At the last appointment, the mean pain threshold and the mean post-operative tenderness were also significantly improved from the baseline (p < 0.001). In patients with insertional tendo Achillis a transverse incision allows a wide exposure and adequate debridement of the tendo Achillis insertion, less soft-tissue injury from aggressive retraction and a safe osteotomy of the posterosuperior corner of the calcaneum.
Health Disparities among Occupations in Taiwan: A Population Study
Authors: Chen Fu‐Li , Chen Peter Y. 
Published: February 2012

Health Disparities among Occupations in Taiwan: A Population Study: Fu‐Li CHEN, et al. Department of Public Health, Fu‐Jen Catholic University, Taiwan—ObjectivesThe first large‐scale population survey was conducted in Taiwan to examine if and to what extent health disparities of four major chronic physical conditions exist among occupations.MethodsFace‐to‐face interviews about two risk behaviors (i.e., cigarette and alcohol use) and four major chronic physical conditions (i.e., cardiovascular disease, diabetes, liver disease and asthma) were conducted with 13,741 workers from nine major categories of occupations.ResultsHealth disparities among occupations were found based on a series of hierarchical logistic regression analyses after controlling for age, sex and two risk behaviors. In general, prevalence rates of cardiovascular disease among elementary occupations and skilled agricultural and fishery workers were approximately two to four times higher than those among other occupations. The above two occupations and plant and machine operators also had higher prevalence rates in diabetes and liver disease.ConclusionsThe results concerning health disparities among occupations provide policymakers and researchers with invaluable benchmarks of chronic physical conditions among occupations. The findings also suggest the importance of investigating causal relationship between these diseases and exposures at work, identifying and reducing unique risk factors and hazard exposures experienced by workers and conducting targeted surveillance and health promotion programs for at‐risk occupations.
Influence of mineralized collagen fibrils on the thermo-sensitivity of an injectable scaffold for bone regeneration
Authors: Huang Zhi , Li Xiaoming , Feng Qingling , Rong Ziqin , Yu Bo 
Published: February 2012

Abstract
Mineralized collagen fibrils are the basis for various connective tissues such as bone and cartilage. Injectable biomaterials incorporating mineralized collagen fibrils are applicable to a wide variety of implant types for bone regeneration. A mineralized collagen fibrils/chitosan thermo-sensitive and injectable scaffold for bone regeneration was prepared successfully. The thermo-sensitive properties of the mineralized collagen fibrils/chitosan system depended on the concentrations of mineralized collagen fibrils. 0.02 g mL−1 of mineralized collagen fibrils filler was appropriate for application since it allowed lower gelation temperature and more rapid gelation following injection, due to the increased hydrogen bonds between the collagen in mineralized collagen fibrils and chitosan.
Dielectric properties of low-temperature sintered Ba(Fe0.5Nb0.5)O3 with BaCu(B2O5) addition
Authors: Lin Ying , Zhu Zhenfeng , Yang Haibo 
Published: February 2012

Abstract
Low loss and low-temperature sintered Ba(Fe0.5Nb0.5)O3 (BFN) ceramics were prepared via a conventional solidstate method with BaCu(B2O5) (BCB) addition. The effect of the BCB content on the dielectric properties of the BFN ceramics was investigated. Low amounts of BCB can significantly reduce the dielectric loss of BFN ceramic from 2 to 0.2, as well as the sintering temperature from 1400°C to 1100°C. The results show that the as-sintered BFN ceramic is a promising candidate material for use in capacitors.
Spinal dural arteriovenous fistulas and intrathecal venous drainage: correlation between digital subtraction angiography, magnetic resonance imaging, and clinical findings
Authors: Hetts Steven W. , Moftakhar Parham , English Joey D. , Dowd Christopher F. , Higashida Randall T. , Lawton Michael T. , Douglas Vanja C. , Halbach Van V. 
Published: February 2012

Object
Spinal dural arteriovenous fistulas (SDAVFs) cause myelopathy through arterialization of the perimedullary venous plexus and venous congestion of the spinal cord. The authors hypothesized that the craniocaudal extent of engorgement of intrathecal draining veins between the fistula site and the point of drainage out of the thecal sac correlates with the degree of myelopathy.

Methods
A retrospective review of the authors' institution's radiology databases identified 31 patients with SDAVFs who had undergone digital subtraction angiography (DSA) and MRI examinations of the spine. The authors counted the number of vertebral body levels of spinal cord enhancement and intrathecal vessel enhancement on T1-weighted postcontrast MRI studies. They also counted the number of levels of cord hyperintensity and intrathecal flow voids on T2-weighted MRI studies. On DSA, the authors identified the number of vertebral body levels of dilated intrathecal draining veins and outflow points from intrathecal veins to epidural veins. Functional status of the patients at the time of diagnosis was assessed using the Aminoff-Logue scale (ALS).

Results
Enlargement of the intrathecal draining veins averaged 10 ± 7.7 spinal levels on DSA. Patients with enlarged draining veins extending 10 or more spinal levels on DSA had worse ALS scores (mean gait 3.4, mean micturition 1.5) than patients with draining veins extending fewer than 10 levels (mean gait 1.8, mean micturition 0.6; p = 0.009 and 0.02, respectively). The number of vertebral body levels of enlarged draining veins correlated with the ALS score (gait r = 0.42, p = 0.009; and micturition r = 0.55, p = 0.0006). More extensive enlarged draining veins were associated with more spinal cord T2 hyperintensity, T2 intrathecal flow voids, and T1 vessel enhancement but not cord enhancement.

Conclusions
The craniocaudal extent of enlarged intrathecal veins draining SDAVF correlates with patient functional status, providing further insight into the pathophysiology of venous hypertensive myelopathy.
CORPORATE GOVERNANCE AND FIRM VALUE IN EMERGING MARKETS AN EMPIRICAL ANALYSIS OF ADR ISSUING EMERGING MARKET FIRMS
Authors: Ficici Aysun , Aybar C. Bulent 
Published: February 2012

This study explores the value implications of good corporate governance for a sample of 54 ADR issuing emerging market firms (EMFs) from 9 countries primarily located in the regions of Asia, Eastern Europe and Latin America and the and employs recently constructed company composite corporate governance metric along with some alternative corporate governance measures associated with the origin of the issuing firm. Although the ADR literature primarily focuses on the impact of subscription to US disclosure requirements we contend that company and country specific corporate governance standards play a significant role in the risk reduction and ensuing value capture. The fundamental inquiry in this study has the following foci: The primary focus is on the impact of corporate governance structures on firm performance as to whether adherence to standards creates market value for ADR issuing EMFs. Do good corporate governance practices affect the value of EMFs? The secondary focus is concerned with whether the impact of corruption level and legal system in a firm’s home country affect the corporate structures of EMFs thus affecting the market value of firms. In this study, we utilize Tobin’s q as the measure of firm performance/market value. Our findings suggest that there is a significant correlation between corporate governance structures of ADR issuing EMFs and their market values and/or performances. The results also indicate that the level of corruption and legal structures in home countries of EMFs strongly impact the corporate governance structures of these firms and sequentially affect their market values. Therefore, this research further contributes to the scholarly findings and suppositions that corporate structures of firms do create consequences on firm value.
Quality of life in adults with juvenile‐onset dermatomyositis: A case–control study
Authors: Tollisen Anita , Sanner Helga , Flatø Berit , Wahl Astrid K. 
Published: February 2012

AbstractObjectiveTo compare quality of life in adults diagnosed with juvenile dermatomyositis (DM) with that of matched controls, and to analyze the association with other disease parameters in patients.MethodsThirty‐nine patients with juvenile DM (ages ≥18 years) were clinically examined and compared with 39 age‐ and sex‐matched controls. Global and health‐related quality of life (HRQOL) were assessed by the Norwegian version of the Quality of Life Scale (QOLS‐N) and the Short Form 36 (SF‐36), respectively. For patients, disease parameters were assessed by the Disease Activity Score (DAS), Health Assessment Questionnaire (HAQ), and Myositis Damage Index (MDI).ResultsCompared to the controls, patients with juvenile DM assessed a median of 22.2 years (range 1.8–36.1 years) after disease onset had reduced HRQOL in general health (P = 0.009) measured by the SF‐36. In patients, a moderate correlation was found between the physical component summary (PCS) score and the DAS (rs = −0.422) and MDI (rs = −0.381), and a strong correlation was found between the PCS score and the HAQ (rs = −0.516). There were no differences between patients and controls in the SF‐36 mental component summary scores. Patients and controls had similar total scores of the QOLS‐N, but differences existed within certain items.ConclusionAdult patients with juvenile DM had, compared to controls, reduced HRQOL in general health measured by the SF‐36, but not in the other subscales of the SF‐36 or in global quality of life measured by the QOLS‐N. An association was found between disease parameters and reduced HRQOL in the physical domains.
Relationship between physical activity and health‐related utility among knee osteoarthritis patients
Authors: Manheim Larry M. , Dunlop Dorothy , Song Jing , Semanik Pamela , Lee Jungwha , Chang Rowland W. 
Published: February 2012

AbstractObjectiveTo estimate the relationship between physical activity and health‐related utility for people with knee osteoarthritis (OA) and implications for designing cost‐effective interventions.MethodsWe used generalized estimating equation regression analysis to estimate partial association of accelerometer‐measured physical activity levels with health‐related utility after controlling for demographics, health status, knee OA severity level, pain, and functioning.ResultsMoving from the lowest to the middle tertile of physical activity level was associated with a 0.071 (P < 0.01) increase in health‐related utility after controlling for demographics and a 0.036 (P < 0.05) increase in utility after controlling for demographics, health status, knee OA severity level, weight, pain, and functional impairments.ConclusionIntervention programs that move individuals out of the lowest tertile of physical activity have the potential to be cost effective.
Nanostructured Poly(styrene‐b‐butadiene‐b‐styrene) (SBS) Membranes for the Separation of Nitrogen from Natural Gas
Authors: Buonomenna Maria Giovanna , Golemme Giovanni , Tone Caterina Maria , De Santo Maria Penelope , Ciuchi Federica , Perrotta Enrico 
Published: February 2012

AbstractThe preparation and characterization of new, tailor‐made polymeric membranes using poly(styrene‐b‐butadiene‐b‐styrene) (SBS) triblock copolymers for gas separation are reported. Structural differences in the copolymer membranes, obtained by manipulation of the self‐assembly of the block copolymers in solution, are characterized using atomic force microscopy, transmission electron microscopy, and the transport properties of three gases (CO2, N2, and CH4). The CH4/N2 ideal selectivity of 7.2, the highest value ever reported for block copolymers, with CH4 permeability of 41 Barrer, is obtained with a membrane containing the higher amount of polybutadiene (79 wt%) and characterized by a hexagonal array of columnar polystyrene cylinders normal to the membrane surface. Membranes with such a high separation factor are able to ease the exploitation of natural gas with high N2 content. The CO2/N2 ideal selectivity of 50, coupled with a CO2 permeability of 289 Barrer, makes SBS a good candidate for the preparation of membranes for the post‐combustion capture of carbon dioxide.