bluuebunny/crossref_metadata_2025_split huggingface dataset:
Evaluation of Left Ventricular Enlargement as a Marker of Early Disease in Familial Dilated Cardiomyopathy
Authors: Fatkin Diane , Yeoh Thomas , Hayward Christopher S. , Benson Victoria , Sheu Angela , Richmond Zara , Feneley Michael P. , Keogh Anne M. , Macdonald Peter S. 
Published: June 2011

Background—
Echocardiographic screening of families with dilated cardiomyopathy has identified a subgroup of asymptomatic relatives with left ventricular enlargement (LVE). The prognostic significance of LVE in this setting is incompletely understood.

Methods and Results—

We evaluated 457 asymptomatic relatives in 128 dilated cardiomyopathy families and identified 110 individuals (24%) with LVE. Serial echocardiograms in 72 untreated LVE relatives showed that 9 individuals (13%) had development of dilated cardiomyopathy over 10 to 152 months (median, 52). Thirty LVE relatives and 30 age- and sex-matched healthy control subjects were evaluated using 2-dimensional and M-mode echocardiography, tissue Doppler imaging, noninvasive pressure-volume assessment, exercise stress echocardiography, and brain natriuretic peptide levels. LVE relatives showed mild defects of systolic and diastolic LV function, with normal filling pressures and exercise-induced increments in systolic contraction in most cases. LV dimensions and fractional shortening most effectively differentiated LVE relatives from control subjects, with other functional indices lacking additive discriminative value. In a receiver operating characteristics analysis, the area under the curve for LV end-diastolic diameter (% predicted) was 0.96 (
P
<0.001). LV end-diastolic diameter (% predicted) >116% or LV end-diastolic diameter (% predicted) 112% to 116%+fractional shortening ≤29% had high sensitivity (100%) and specificity (93%) for LVE relatives and identified 8 of 9 progressors.

Conclusions—
LVE is a common finding in asymptomatic relatives in dilated cardiomyopathy families and can be a marker of preclinical cardiomyopathy. Assessment of LV size and contractile function is required for differentiating between pathological and physiological causes of LVE and may help to identify those at risk of disease progression.
Validation of In Vivo Magnetic Resonance Imaging Blood–Brain Barrier Permeability Measurements by Comparison With Gold Standard Histology
Authors: Hoffmann Angelika , Bredno Jörg , Wendland Michael F. , Derugin Nikita , Hom Jason , Schuster Tibor , Su Hua , Ohara Peter T. , Young William L. , Wintermark Max 
Published: June 2011

Background and Purpose—
We sought to validate the blood–brain barrier permeability measurements extracted from perfusion-weighted MRI through a relatively simple and frequently applied model, the Patlak model, by comparison with gold standard histology in a rat model of ischemic stroke.

Methods—
Eleven spontaneously hypertensive rats and 11 Wistar rats with unilateral 2-hour filament occlusion of the right middle cerebral artery underwent imaging during occlusion at 4 hours and 24 hours after reperfusion. Blood–brain barrier permeability was imaged by gradient echo imaging after the first pass of the contrast agent bolus and quantified by a Patlak analysis. Blood–brain barrier permeability was shown on histology by the extravasation of Evans blue on fluorescence microscopy sections matching location and orientation of MR images. Cresyl-violet staining was used to detect and characterize hemorrhage. Landmark-based elastic image registration allowed a region-by-region comparison of permeability imaging at 24 hours with Evans blue extravasation and hemorrhage as detected on histological slides obtained immediately after the 24-hour image set.

Results—
Permeability values in the nonischemic tissue (marginal mean±SE: 0.15±0.019 mL/miṅ100 g) were significantly lower compared to all permeability values in regions of Evans blue extravasation or hemorrhage. Permeability values in regions of weak Evans blue extravasation (0.23±0.016 mL/miṅ100 g) were significantly lower compared to permeability values of in regions of strong Evans blue extravasation (0.29±0.020 mL/miṅ100 g) and macroscopic hemorrhage (0.35±0.049 mL/miṅ100 g). Permeability values in regions of microscopic hemorrhage (0.26±0.024 mL/miṅ100 g) only differed significantly from values in regions of nonischemic tissue (0.15±0.019 mL/miṅ100 g).

Conclusions—
Areas of increased permeability measured in vivo by imaging coincide with blood–brain barrier disruption and hemorrhage observed on gold standard histology.
Recombinant Tissue-Type Plasminogen Activator Use for Ischemic Stroke in the United States
Authors: Adeoye Opeolu , Hornung Richard , Khatri Pooja , Kleindorfer Dawn 
Published: June 2011

Background and Purpose—
Recombinant tissue-type plasminogen activator (rtPA) is the only approved therapy for acute ischemic stroke (AIS). In 2004, 1.8% to 2.1% of AIS patients in the United States received rtPA. Given incentives from regulatory agencies and payors to increase rtPA use, we hypothesized that rtPA use in the United States would increase from 2005 to 2009.

Methods—

AIS cases were defined by exclusion of hemorrhagic stroke and transient ischemic attack International Classification of Diseases 9
th
revision codes (430, 431, 432, and 435) from diagnosis-related groups 14, 15, 524, and 559 discharges. Patients receiving thrombolytics were identified using International Classification of Diseases 9
th
revision code 99.10 (Medicare Provider and Analysis Review and Premier databases) and pharmacy billing records (Premier). Change over time and differences between databases were tested using negative binomial regression.

Results—

Within Medicare Provider and Analysis Review, thrombolytic use increased from 1.1% in 2005 to 3.4% in 2009 (
P
<0.001 for trend). Within Premier, thrombolytic use increased from 1.4% in 2005 to 3.7% in 2009 for all cases (
P
<0.001). Analysis of pharmacy billing records in Premier for 50-mg or 100-mg doses of rtPA showed that 3.4% of AIS cases were treated in 2009. Inclusion of patients with transient ischemic attack or hemorrhagic stroke International Classification of Diseases 9
th
revision codes who received any thrombolytic as “ischemic stroke patients receiving rtPA” changed the rate of thrombolysis to 5.2%.

Conclusions—
In 2009, 3.4% to 5.2% of AIS patients in the United States received thrombolytics, approximately double the rate of treatment in 2005. Rapid recognition and transport and quick treatment in the emergency department remain goals for further improving treatment rates.
HIV-related knowledge, attitudes and behaviours among college students in China
Authors: Tung Wei-Chen , Hu Jie , Efird Jimmy Thomas , Yu Liping , Su Wei 
Published: June 2011

Objectives: To assess the knowledge, attitudes, sources of HIV information and behaviours related to HIV, and to explore the difference in the HIV knowledge and attitudes between genders and school years among college students in China. Design: Descriptive, cross-sectional. Setting: 475 college students from two universities in China. Method: Data were collected with a self-report questionnaire through the Internet. Results: Only 24.2 per cent of the participants were aware that HIV could be spread through infected semen, and only 10.5 per cent were aware that condoms would decrease the risk of HIV transmission. The major sources of HIV information were through the mass media (i.e. 69.5 per cent Internet, 65.9 per cent newspaper and magazines, 58.3 per cent television). Only 17.9 per cent reported ever having had sex, and only 21.2 per cent used condoms during each sexual encounter. Females were more likely to obtain HIV information from school teachers ( OR = 2.24, 95 per cent CI: 1.53–3.28, p = 0.000) and health professionals ( OR = 1.95, 95 per cent CI: 1.27–2.99, p = 0.002) than males. Males were more likely to discuss sexually transmitted infections through online chat or email with strangers ( OR = 0.46, 95 per cent CI: 0.29–0.71, p = 0.001). Higher school grade was associated with better HIV knowledge in this study, with graduate students, seniors, and sophomores having higher scores on HIV knowledge and HIV transmission myth subscales than freshman. Conclusion: Low rates of condom use and insufficient knowledge on HIV prevention among college students in China remain a significant problem. This research provides additional insights that may be used to develop effective HIV prevention strategies in China.
Nonexophytic Nasopharyngeal Carcinoma
Authors: Loh Kwok Seng , Petersson Fredrik 
Published: June 2011

ObjectiveNasopharyngeal carcinoma (NPC) usually presents with an exophytic mass. However, some patients present with biopsy‐proven NPC but normal‐appearing nasopharynx on endoscopic examination (nonexophytic NPC). The authors aim to characterize the clinicopathological features and survival outcomes of nonexophytic NPC in a high‐incidence area.Study Design and SettingA retrospective cohort analysis of 274 patients with NPC in a tertiary institution.Subjects and MethodsOn the basis of endoscopic findings, the patients were categorized into nonexophytic and exophytic NPC. Clinical, pathological, and survival outcomes between the 2 groups were compared.ResultsNonexophytic NPC was present in 24 patients (8.8%). A greater proportion of patients with nonexophytic NPC presented with T1 tumors compared to patients with exophytic NPC (70.8% vs 35.2%, P =. 004). Similarly, a higher proportion of patients with nonexophytic NPC compared with exophytic NPC presented with both N3 and M1 disease (37.5% vs 13.2%, P =. 01 and 25.0% vs 6%, P =. 005, respectively). The mean duration of symptoms of patients did not differ significantly. The 5‐year disease‐specific and disease‐free survivals did not show any significant differences.ConclusionNonexophytic NPC appears to be associated with higher risks of both N3 and M1 disease at presentation. However, these patients have similar treatment outcomes compared to patients with exophytic NPC. Although nonexophytic NPC appears to be an aggressive variant, current treatment protocols are as effective as for the group with exophytic NPC. Awareness of the existence of nonexophytic NPC is important for adequate diagnostic workup of patients with this subset of NPC.
An experimental and modelling study of the combustion and emission characteristics for gasoline–diesel dual-fuel engines
Authors: Cha J , Kwon S , Park S 
Published: June 2011

In this study, the combustion and emissions characteristics of gasoline–diesel dual-fuel operation were investigated both experimentally and numerically. Gasoline fuel was injected through an intake port, and diesel fuel was injected directly into the combustion chamber to trigger combustion. The tested concentrations of diesel fuel were 30 per cent and 40 per cent, and it was found that a smaller amount of diesel fuel forms a more homogeneous mixture. Numerical calculations were performed for selected injection timings (i.e. −20° crank angle (CA) after top dead centre) for increased understanding of the combustion regime of dual-fuel combustion using the KIVA code coupled with the primary reference fuels mechanism. The injection timings of the diesel fuel were swept from −40° to +3° CA. The results showed that gasoline–diesel dual-fuel operation exhibited significant reductions in soot and nitrogen oxide emissions by suppressing the formation of locally rich mixtures or high-temperature regions. However, the carbon monoxide and hydrocarbon emissions were increased for a wide range of injection timings.
A simple, economical, and effective portable paediatric mock circulatory system
Authors: Vandenberghe S , Shu F , Arnold D K , Antaki J F 
Published: June 2011

Ventricular assist devices (VADs) and total artificial hearts have been in development for the last 50 years. Since their inception, simulators of the circulation with different degrees of complexity have been produced to test these devices in vitro. Currently, a new path has been taken with the extensive efforts to develop paediatric VADs, which require totally different design constraints. This paper presents the manufacturing details of an economical simulator of the systemic paediatric circulation. This simulator allows the insertion of a paediatric VAD, includes a pumping ventricle, and is adjustable within the paediatric range. Rather than focusing on complexity and physiological simulation, this simulator is designed to be simple and practical for rapid device testing. The simulator was instrumented with medical sensors and data were acquired under different conditions with and without the new PediaFlow™ paediatric VAD. The VAD was run at different impeller speeds while simulator settings such as vascular resistance and stroke volume were varied. The hydraulic performance of the VAD under pulsatile conditions could be characterized and the magnetic suspension could be tested via manipulations such as cannula clamping. This compact mock loop has proven to be valuable throughout the PediaFlow development process and has the advantage that it is uncomplicated and can be manufactured cheaply. It can be produced by several research groups and the results of different VADs can then be compared easily.
Identifying the invisible: The experiences of prostitution among persons with intellectual disabilities: Implications for social work
Authors: Kuosmanen Jari , Starke Mikaela 
Published: June 2011

• Summary: This article explores a relatively uncharted research area. The focus of the analysis is on how professionals working in care provision units, specialized prostitution units, the police, social services and special schools detect and deal with prostitution among people with intellectual disabilities. The data were obtained primarily through focus group interviews. The study shows that organizational specialization in different authorities and services makes it difficult to identify and work with this group. Clients with complex problems tend to find themselves in between the jurisdictional fields of different authorities, meaning that many do not receive the support that they need. • Findings: In recent decades social work has undergone increasing balkanization and specialization. Each particular organization is regulated by specific legislation, regulations, forms of knowledge and normative assumptions. Professionals working with people with intellectual disabilities have difficulties in detecting prostitution among their clients, whilst those who work with prostitution lack the knowledge and methods to work with intellectual disabilities. At the same time, social work with these individuals is conducted within a field of tension between the client′s right of self-determination and professionals’ responsibilities for their well-being. • Applications: The study demonstrates that, with this type of complex problem, it is important to establish different types of collaboration between different organizations. However, due to the risk of increased control being detrimental to clients, collaboration needs to be founded on the client’s needs and right to self-determination.
miR-181b is a biomarker of disease progression in chronic lymphocytic leukemia
Authors: Visone Rosa , Veronese Angelo , Rassenti Laura Z. , Balatti Veronica , Pearl Dennis K. , Acunzo Mario , Volinia Stefano , Taccioli Cristian , Kipps Thomas J. , Croce Carlo M. 
Published: June 2011

Abstract
MicroRNAs play a crucial role in chronic lymphocytic leukemia. We investigated whether microRNAs can discriminate patients with a progressive disease from patients with a stable disease. We analyzed microRNA expression on leukemic cells isolated from 358 sequential samples of 114 patients with either stable or progressive disease. We found that during the course of the disease the expression values of miR-181b, the most dysregulated microRNA, decreased in samples of patients with a progressive (P < .001, training and validation sets) but not in samples of patients with a stable disease (P = .3, training set; P = .2, validation set) over time. A drop of ≥ 50% between sequential samples and/or a miR-181b value ≤ 0.005 at the starting time point were significant to differentiate progressive from stable disease (P = .004, training set; P < .001, validation set). These parameters were associated with high risk of requiring treatment (risk ratio, 5.8; 95% confidence interval, 2.5-14.9). We also observed that miR-181b targets Mcl-1 protein and that the decrease of its expression inversely correlated with increased protein levels of MCL1 and BCL2 target genes. We conclude that parameters defined on the basis of the miR-181b expression values specify disease progression in chronic lymphocytic leukemia and are associated with clinical outcome.
Characterization of porcine dendritic cell response to Streptococcus suis
Authors: Lecours Marie-Pier , Segura Mariela , Lachance Claude , Mussa Tufaria , Surprenant Charles , Montoya Maria , Gottschalk Marcelo 
Published: June 2011

Abstract

Streptococcus suis is a major swine pathogen and important zoonotic agent causing mainly septicemia and meningitis. However, the mechanisms involved in host innate and adaptive immune responses toward S. suis as well as the mechanisms used by S. suis to subvert these responses are unknown. Here, and for the first time, the ability of S. suis to interact with bone marrow-derived swine dendritic cells (DCs) was evaluated. In addition, the role of S. suis capsular polysaccharide in modulation of DC functions was also assessed. Well encapsulated S. suis was relatively resistant to phagocytosis, but it increased the relative expression of Toll-like receptors 2 and 6 and triggered the release of several cytokines by DCs, including IL-1β, IL-6, IL-8, IL-12p40 and TNF-α. The capsular polysaccharide was shown to interfere with DC phagocytosis; however, once internalized, S. suis was readily destroyed by DCs independently of the presence of the capsular polysaccharide. Cell wall components were mainly responsible for DC activation, since the capsular polysaccharide-negative mutant induced higher cytokine levels than the wild-type strain. The capsular polysaccharide also interfered with the expression of the co-stimulatory molecules CD80/86 and MHC-II on DCs. To conclude, our results show for the first time that S. suis interacts with swine origin DCs and suggest that these cells might play a role in the development of host innate and adaptive immunity during an infection with S. suis serotype 2.
Comparative thermodynamic studies on substrate and product binding of O-Acetylserine Sulfhydrylase reveals two different ligand recognition modes†
Authors: Banerjee Shrijita , Ekka Mary K , Kumaran Sangaralingam 
Published: June 2011

Abstract

Background
The importance of understanding the detailed mechanism of cysteine biosynthesis in bacteria is underscored by the fact that cysteine is the only sulfur donor for all cellular components containing reduced sulfur. O-acetylserine sulfhydrylase (OASS) catalyzes this crucial last step in the cysteine biosynthesis and has been recognized as an important gene for the survival and virulence of pathogenic bacteria. Structural and kinetic studies have contributed to the understanding of mechanistic aspects of OASS, but details of ligand recognition features of OASS are not available. In the absence of any detailed study on the energetics of ligand binding, we have studied the thermodynamics of OASS from Salmonella typhimurium (St OASS), Haemophilus influenzae (Hi OASS), and Mycobacterium tuberculosis (MtOASS) binding to their substrate O-acetylserine (OAS), substrate analogue (methionine), and product (cysteine).

Results
Ligand binding properties of three OASS enzymes are studied under defined solution conditions. Both substrate and product binding is an exothermic reaction, but their thermodynamic signatures are very different. Cysteine binding to OASS shows that both enthalpy and entropy contribute significantly to the binding free energy at all temperatures (10-30°C) examined. The analyses of interaction between OASS with OAS (substrate) or methionine (substrate analogue) revealed a completely different mode of binding. Binding of both OAS and methionine to OASS is dominated by a favorable entropy change, with minor contribution from enthalpy change (ΔHSt-Met = -1.5 ± 0.1 kJ/mol; TΔSSt-Met = 8.2 kJ/mol) at 20°C. Our salt dependent ligand binding studies indicate that methionine binding affinity is more sensitive to [NaCl] as compared to cysteine affinity.

Conclusions
We show that OASS from three different pathogenic bacteria bind substrate and product through two different mechanisms. Results indicate that predominantly entropy driven methionine binding is not mediated through classical hydrophobic binding, instead, may involve desolvation of the polar active site. We speculate that OASS in general, may exhibit two different binding mechanisms for recognizing substrates and products.
Using affinity propagation for identifying subspecies among clonal organisms: lessons from M. tuberculosis
Authors: Borile Claudio , Labarre Mathieu , Franz Silvio , Sola Christophe , Refrégier Guislaine 
Published: June 2011

Abstract

Background
Classification and naming is a key step in the analysis, understanding and adequate management of living organisms. However, where to set limits between groups can be puzzling especially in clonal organisms. Within the Mycobacterium tuberculosis complex (MTC), the etiological agent of tuberculosis (TB), experts have first identified several groups according to their pattern at repetitive sequences, especially at the CRISPR locus (spoligotyping), and to their epidemiological relevance. Most groups such as "Beijing" found good support when tested with other loci. However, other groups such as T family and T1 subfamily (belonging to the "Euro-American" lineage) correspond to non-monophyletic groups and still need to be refined. Here, we propose to use a method called Affinity Propagation that has been successfully used in image categorization to identify relevant patterns at the CRISPR locus in MTC.

Results
To adequately infer the relative divergence time between strains, we used a distance method inspired by the recent evolutionary model by Reyes et al. We first confirm that this method performs better than the Jaccard index commonly used to compare spoligotype patterns. Second, we document the support of each spoligotype family among the previous classification using affinity propagation on the international spoligotyping database SpolDB4. This allowed us to propose a consensus assignation for all SpolDB4 spoligotypes. Third, we propose new signatures to subclassify the T family.

Conclusion
Altogether, this study shows how the new clustering algorithm Affinity Propagation can help building or refining clonal organims classifications. It also describes well-supported families and subfamilies among M. tuberculosis complex, especially inside the modern "Euro-American" lineage.