bluuebunny/crossref_metadata_2025_split huggingface dataset:
Echocardiographic Variables After Left Ventricular Assist Device Implantation Associated With Adverse Outcome
Authors: Topilsky Yan , Hasin Tal , Oh Jae K. , Borgeson Daniel D. , Boilson Barry A. , Schirger John A. , Clavell Alfredo L. , Frantz Robert P. , Tsutsui Rayji , Liu Mingya , Maltais Simon , Kushwaha Sudhir S. , Pereira Naveen L. , Park Soon J. 
Published: September 2011

Background—
Operative mortality after left ventricular assist device (LVAD) implantation is heavily influenced by patient selection and the technical difficulty of surgery. However, how we treat our patients and LVAD setting may affect the patient outcome beyond this period. We postulated that the presence of echocardiographic variables 1 month after surgery suggesting appropriate degree of LV unloading and an adequate forward flow would be important in determining clinical outcomes after the initial successful LVAD implantation.

Methods and Results—

We retrospectively analyzed various variables in echocardiographic examinations performed 30 days after LVAD implant in 76 consecutive patients receiving continuous flow device for their association with a compound end point (90-day mortality, readmission for heart failure, or New York Heart Association class III or higher at the end of the 90-day period). The echocardiographic associations examined included estimated LVAD flow, with and without native LV contribution, interventricular septal position, the status of aortic valve opening, an estimated left atrial pressure (ELAP), the mitral flow E-wave deceleration time, and the ratio of deceleration time to E-wave velocity (mitral deceleration index [MDI]). Four patients died during the 30- to 90-day period, 6 patients were readmitted for heart failure, and 25 patients were considered to have New York Heart Association class III or higher at the end of the 90-day period. Variables associated with adverse outcome included increased ELAP (odds ratio, 1.30 [1.16–1.48];
P
<0.0001), MDI <2 ms/[cm/s] (odds ratio, 4.4 implantation [1.22–18];
P
=0.02) and decreased tricuspid lateral annulus velocity (odds ratio, 0.70 implantation [0.48–0.95];
P
=0.02). A leftward deviation of interventricular septum was associated with a worse outcome (odds ratio, 3.03 implantation [1.21–13.3];
P
=0.01).

Conclusions—
Mortality and heart failure after LVAD surgery appear to be predominantly determined by echocardiographic evidence of inefficient unloading of the left ventricle and persistence of right ventricular dysfunction. Increased estimated LA pressure and short MDI are associated with worse mid term outcome. Leftward deviation of the septum is associated with worse outcome as well.
Modeling of thermal residual stress in environmental barrier coated fiber reinforced ceramic matrix composites
Authors: Abdul-Aziz Ali , Bhatt Ramakrishna T 
Published: September 2011

For SiC/SiC composites to replace metallic materials in future turbine engines, prime reliant environmental barrier coatings (EBCs) are required. However, due to the mismatch in thermal expansion and elastic modulus between the substrate and the coating, thermal residual stresses are generated in the coating after processing as well as during exposure to turbine engine operating conditions. The nature and magnitude of the thermal stresses will have a profound effect on the durability and reliability of the EBC. To estimate the magnitude of in-plane ( x- and y-directions) and through-the-thickness ( z-direction) thermal residual stresses in the coating, a finite element model (FEM) was developed. Using FEM, the residual stresses were predicted for three multilayered EBC systems considered for the SiC/SiC composites: (1) barium strontium aluminum silicate, (2) ytterbium disilicate, and (3) ytterbium monosilicate. Influence of thickness and modulus of the coating layer on the thermal residual stress were modeled. Results indicate that thermal residual stresses in the SiC/SiC composite substrate are compressive and in all the three coatings tensile. Further examination indicates that in the z-direction, tensile stresses in all three systems are negligible, but in-plane tensile stresses can be significant depending on the composition of the constituent layer and the distance from the substrate. Comparison of predicted thermal residual stresses in the three systems shows that the ytterbium monosilicate system has the highest stress (~395 MPa), while the other two systems averaged about 80 MPa in one of the coating layers. A parametric analysis conducted indicates that lowering the modulus of the coating can lower the thermal residual stresses.
The time perspective of the Alzheimer caregiver
Authors: Potgieter Johan C. , Heyns Pieter M. , Lens Willy 
Published: September 2011

Purpose of the study: Caring for a spouse diagnosed with Alzheimer’s disease holds potentially severe negative consequences for the physical and psychological well-being of the caregiver. As it is known that the maintenance of a flexible time perspective holds benefits for individual health, the main purpose of this study was to identify and describe the changes in the time perspective of persons caring for a spouse diagnosed with Alzheimer’s disease. Design and Methods: The SELE instrument was administered in order to shed light on the time perspective of a total of 40 participants. A criterion group design was used, and a mixed methods approach adopted during the collection and analysis of data. Results: The results of this research project highlighted the existence of a number of important differences regarding the time perspective of caregivers and non-caregivers. The time perspective of caregivers was severely affected by the caregiving situation and the accompanying grieving process. This proved to be one potential avenue through which the caregiving situation has its negative effect on caregivers’ well-being. Implications: Owing to the usually insufficient funding for the care of demented patients, research regarding the identification of potential cost-effective methods to enhance the resilience of caregivers is of the essence. Maintenance of a balanced time perspective might prove to be to the benefit of caregiver psychological well-being.
An intact PDZ motif is essential for correct P2Y12 purinoceptor traffic in human platelets
Authors: Nisar Shaista , Daly Martina E. , Federici Augusto B. , Artoni Andrea , Mumford Andrew D. , Watson Stephen P. , Mundell Stuart J. 
Published: September 2011

Abstract
The platelet P2Y12 purinoceptor (P2Y12R), which plays a crucial role in hemostasis, undergoes internalization and subsequent recycling to maintain receptor responsiveness, processes that are essential for normal platelet function. Here, we observe that P2Y12R function is compromised after deletion or mutation of the 4 amino acids at the extreme C-terminus of this receptor (ETPM), a putative postsynaptic density 95/disc large/zonula occludens-1 (PDZ)–binding motif. In cell line models, removal of this sequence or mutation of one of its core residues (P341A), attenuates receptor internalization and receptor recycling back to the membrane, thereby blocking receptor resensitization. The physiologic significance of these findings in the regulation of platelet function is shown by identification of a patient with a heterozygous mutation in the PDZ binding sequence of their P2Y12R (P341A) that is associated with reduced expression of the P2Y12R on the cell surface. Importantly, platelets from this subject showed significantly compromised P2Y12R recycling, emphasizing the importance of the extreme C-terminus of this receptor to ensure correct receptor traffic.
Wnt4 regulates thymic cellularity through the expansion of thymic epithelial cells and early thymic progenitors
Authors: Heinonen Krista M. , Ruiz Vanegas Juan , Brochu Sylvie , Shan Jingdong , Vainio Seppo J. , Perreault Claude 
Published: September 2011

Abstract
Thymus atrophy is the most common immunopathology in humans, and its occurrence is hastened by several factors that coalesce in patients receiving chemotherapy and most of all in recipients of hematopoietic cell transplantation. We have shown previously that posthematopoietic cell transplantation thymic function was improved by retroviral overexpression of Wnt4 in donor hematopoietic cells. Here, by using both conventional and conditional null mutant mice, we show that Wnt4 regulates steady-state thymic cellularity by a thymic epithelial cell (TEC)–dependent mechanism. The absence of Wnt4 suppressed fetal and postnatal thymic expansion and resulted in decreased TEC numbers, an alteration of the medullary-to-cortical TEC ratio, and a disproportionate loss of the most immature cKithi thymocyte precursors. Wnt4 also is implicated in the maintenance of adult thymopoiesis, although the impact of its deletion once thymic involution has been initiated is more subtle. Together, our results show that Wnt4 controls thymic size by modulating TEC expansion and the earliest, TEC-dependent steps of thymocyte development both in the fetal and postnatal thymus. Wnt4 and its downstream signaling pathways could thus represent interesting candidates to improve thymic output in subjects with thymic atrophy.
Lack of clarity in the definition of treatment-related mortality: pediatric acute leukemia and adult acute promyelocytic leukemia as examples
Authors: Ethier Marie-Chantal , Blanco Esther , Lehrnbecher Thomas , Sung Lillian 
Published: September 2011

Abstract
Treatment-related mortality (TRM) is important in acute lymphoblastic leukemia and acute myeloid leukemia (AML); however, little is known about how TRM is defined across trials. Two major problems are related to what constitutes treatment versus disease-related cause of death and to TRM attribution (for example, death because of infection or hemorrhage). To address the former, we conducted a systematic review of randomized therapeutic pediatric acute leukemia and adult/pediatric acute promyelocytic leukemia trials and any study type focused on TRM in pediatric acute leukemia. We described definitions used for TRM. Sixty-six studies were included. Few therapeutic pediatric acute lymphoblastic leukemia studies (2/32, 6.3%) provided definitions for TRM, whereas more therapeutic pediatric AML studies (6/9, 66.7%) provided definitions. There was great heterogeneity in TRM classification. The authors of most studies relied on deaths during induction or in remission to delineate whether a death was TRM. However, 44.4% of therapeutic AML studies used death within a specific time frame to delineate TRM. We suggest that a consistent approach to defining and determining attribution for TRM in acute leukemia is an important future goal. Harmonization of definitions across the age spectrum would allow comparisons between pediatric and adult studies.
Induction of erythropoiesis using human vascular networks genetically engineered for controlled erythropoietin release
Authors: Lin Ruei-Zeng , Dreyzin Alexandra , Aamodt Kristie , Li Dan , Jaminet Shou-Ching S. , Dudley Andrew C. , Melero-Martin Juan M. 
Published: September 2011

Abstract
For decades, autologous ex vivo gene therapy has been postulated as a potential alternative to parenteral administration of recombinant proteins. However, achieving effective cellular engraftment of previously retrieved patient cells is challenging. Recently, our ability to engineer vasculature in vivo has allowed for the introduction of instructions into tissues by genetically modifying the vascular cells that build these blood vessels. In the present study, we genetically engineered human blood–derived endothelial colony-forming cells (ECFCs) to express erythropoietin (EPO) under the control of a tetracycline-regulated system, and generated subcutaneous vascular networks capable of systemic EPO release in immunodeficient mice. These ECFC-lined vascular networks formed functional anastomoses with the mouse vasculature, allowing direct delivery of recombinant human EPO into the bloodstream. After activation of EPO expression, erythropoiesis was induced in both normal and anemic mice, a process that was completely reversible. This approach could relieve patients from frequent EPO injections, reducing the medical costs associated with the management of anemia. We propose this ECFC-based gene-delivery strategy as a viable alternative technology when routine administration of recombinant proteins is needed.
Attenuation of antigen-induced airway hyperresponsiveness and inflammation in CXCR3 knockout mice
Authors: Lin Yi , Yan Haibo , Xiao Yu , Piao Hongmei , Xiang Ruolan , Jiang Lei , Chen Huaxia , Huang Kewu , Guo Zijian , Zhou Wexun , Lu Bao , Gao Jinming 
Published: September 2011

AbstractBackgroundCD8+ T cells participate in airway hyperresponsiveness (AHR) and allergic pulmonary inflammation that are characteristics of asthma. CXCL10 by binding to CXCR3 expressed preferentially on activated CD8+ T cells, attracts T cells homing to the lung. We studied the contribution and limitation of CXCR3 to AHR and airway inflammation induced by ovalbumin (OVA) using CXCR3 knockout (KO) mice.MethodsMice were sensitized and challenged with OVA. Lung histopathological changes, AHR, cellular composition and levels of inflammatory mediators in bronchoalveolar lavage (BAL) fluid, and lungs at mRNA and protein levels, were compared between CXCR3 KO mice and wild type (WT) mice.ResultsCompared with the WT controls, CXCR3 KO mice showed less OVA-induced infiltration of inflammatory cells around airways and vessels, and less mucus production. CXCR3 KO mice failed to develop significant AHR. They also demonstrated significantly fewer CD8+ T and CD4+ T cells in BAL fluid, lower levels of TNFα and IL-4 in lung tissue measured by real-time RT-PCR and in BAL fluid by ELISA, with significant elevation of IFNγ mRNA and protein expression levels.ConclusionsWe conclude that CXCR3 is crucial for AHR and airway inflammation by promoting recruitment of more CD8+ T cells, as well as CD4+ T cells, and initiating release of proinflammatory mediators following OVA sensitization and challenge. CXCR3 may represent a novel therapeutic target for asthma.
Amplified fragment length polymorphism of clinical and environmental Vibrio cholerae from a freshwater environment in a cholera-endemic area, India
Authors: Mishra Arti , Taneja Neelam , Sharma Ram K , Kumar Rahul , Sharma Naresh C , Sharma Meera 
Published: September 2011

AbstractBackgroundThe region around Chandigarh in India has witnessed a resurgence of cholera. However, isolation ofV. choleraeO1 from the environment is infrequent. Therefore, to study whether environmental nonO1-nonO139 isolates, which are native to the aquatic ecosystem, act as precursors for pathogenic O1 strains, their virulence potential and evolutionary relatedness was checked.MethodsV. choleraewas isolated from clinical cases of cholera and from water and plankton samples collected from freshwater bodies and cholera-affected areas. PCR analysis for thectxA, ctxB, tcpA, toxTandtoxRgenes and AFLP with six primer combinations was performed on 52 isolates (13 clinical, 34 environmental and 5 reference strains).ResultsAll clinical and 3 environmental isolates belonged to serogroup O1 and remaining 31 environmentalV. choleraewere nonO1-nonO139. Serogroup O1 isolates werectxA, tcpA(ElTor),ctxB(Classical),toxRandtoxTpositive. NonO1-nonO139 isolates possessedtoxR, but lackedctxAandctxB; only one isolate was positive fortoxTandtcpA. Using AFLP, 2.08% of theV. choleraegenome was interrogated. Dendrogram analysis showed one large heterogeneous clade (n = 41), with two compact and distinct subclades (1a and 1b), and six small mono-phyletic groups. AlthoughV. choleraeO1 isolates formed a distinct compact subclade, they were not clonal. A clinical O1 strain clustered with the nonO1-nonO139 isolates; one strain exhibited 70% similarity to the Classical control strain, and all O1 strains possessed an ElTor variant-specific fragment identified with primer ECMT. Few nonO1-nonO139 isolates from widely separated geographical locations intermingled together. Three environmental O1 isolates exhibited similar profiles to clinical O1 isolates.ConclusionIn a unique study from freshwater environs of a cholera-endemic area in India over a narrow time frame, environmentalV. choleraepopulation was found to be highly heterogeneous, diverse and devoid of major virulence genes. O1 and nonO1-nonO139 isolates showed distinct lineages. Clinical isolates were not clonal but were closely related, indicating accumulation of genetic differences over a short time span. Though, environment plays an important role in the spread of cholera, the possibility of an origin of pathogenic O1 strains from environmental nonO1-nonO139 strains seems to be remote in our region.
Treatment incidence of and medical utilization for hospitalized subjects with pathologic fractures in Taiwan-Survey of the 2008 National Health Insurance data
Authors: Lee Yi-Hui , Hsu Yuan-Nian , Yu I-Liang , Phan Dinh-Van , Chou Pesus , Chan Chien-Lung , Yang Nan-Ping 
Published: September 2011

Abstract

Background
Almost all studies of pathologic fractures have been conducted based on patients with tumours and hospital-based data; however, in the present study, a nationwide epidemiological survey of pathologic fractures in Taiwan was performed and the medical utilization was calculated.

Methods
All claimants of Taiwan's National Health Insurance (NHI) Program in 2008 were included in the target population of this descriptive cross-sectional study. The registration and inpatient expenditure claims data by admission of all hospitalized subjects of the target population were examined and the concomitant International Classification of Diseases, Ninth Revision, Clinical Modification (ICD-9-CM) diagnosis codes were evaluated and classified into seven major categories of fracture.

Results
A total of 5,244 incident cases of pathologic fracture were identified from the 2008 hospitalized patient claims data. The incidence of pathologic fracture of the humerus, distal radius/ulna, vertebrae, femoral neck, other part of the femur, and tibia/fibula was 0.67, 0.08, 10.58, 1.11, 0.56, and 0.11 per 100,000 people, respectively, and patients with those fractures were hospitalized for 43.9 ± 42.9, 31.1 ± 32.9, 29. 4 ± 34.4, 43.3 ± 41.2, 42.4 ± 38.1, and 42.0 ± 32.8 days, respectively, incurring an average medical cost of US$11,049 ± 12,730, US$9,181 ± 12,115, US$6,250 ± 8,021, US$9,619 ± 8,906, US$10,646 ± 11,024, and US$9,403 ± 9,882, respectively. The percentage of patients undergoing bone surgery for pathologic fracture of the humerus, radius/ulna, vertebrae, femoral neck, other part of the femur, and tibia/fibula was 31.2%, 44.4%, 11.3%, 46.5%, 48.4%, and 52.5% respectively.

Conclusions
Comparing Taiwan to other countries, this study observed for Taiwan higher medical utilization and less-aggressive surgical intervention for patients hospitalized with pathologic fractures.
Genetic polymorphism of merozoite surface protein-1 and merozoite surface protein-2 in Plasmodium falciparum isolates from Brazzaville, Republic of Congo
Authors: Mayengue Pembe Issamou , Ndounga Mathieu , Malonga Freddy Vladimir , Bitemo Michel , Ntoumi Francine 
Published: September 2011

Abstract

Background
The characterization of malaria parasite populations circulating in an area is part of site characterization, as a basis for evaluating the impact of malaria interventions on genetic diversity, parasite species, and multiplicity of infection. The present study was aimed at analysing genetic diversity of Plasmodium falciparum merozoite surface proteins 1 and 2 (MSP-1 and MSP-2) and to determine the multiplicity of infection in clinical isolates collected from children living in the Southern district of Brazzaville in the Republic of Congo.

Methods
A total of 125 isolates from patients with uncomplicated malaria attending Terinkyo and Madibou health centres were collected between January and June 2005 while evaluating the therapeutic efficacy of amodiaquine-artesunate combination. DNA was extracted and msp-1 and msp-2 genes were genotyped using allele-specific nested-PCR.

Results
Out of 468 distinct fragments detected, 15 msp-1 and 20 msp-2 genotypes were identified. For the msp-1 gene, K1 family was the predominant allelic type carried alone or in association with RO33 and Mad20 types, whereas the 3D7 family was the most prevalent in the msp-2 gene. Overall, the mean multiplicity of infection was 2.2. Out of 125 samples, 104 (83%) harboured more than one parasite genotype. There was no statistical significant difference in the multiplicity of infection by either sex or age of patients. However, a statistically significant correlation was found between parasite densities and the number of genotypes.

Conclusion
Polymorphism in P. falciparum clinical isolates from Brazzaville was high and mainly of multiple clones. The basis for the positive association between parasite densities and multiplicity of infection is discussed.
Baseline results of the first malaria indicator survey in Iran at household level
Authors: Mohammadi Mahdi , Ansari-Moghaddam Alireza , Raiesi Ahmad , Rakhshani Fatemeh , Nikpour Fatemeh , Haghdost Aliakbar , Ranjbar Mansoor , Taghizadeh-Asl Rahim , Sakeni Mohammad , Safari Reza , Saffari Mehdi 
Published: September 2011

Abstract

Background
Malaria is one of the leading causes of sickness and death in the developing world, causing more than a million deaths and around 250 million new cases annually worldwide. The aim of this comprehensive survey was to provide information on malaria indicators at household level in high-risk malaria areas in Iran.

Methods
In a cluster randomized cross-sectional survey data were collected from 5,456 households in both rural and urban areas of 20 malaria-affected districts of Iran. All the fieldwork was done by trained interviewers and a validated questionnaire. The questionnaire comprised baseline characteristics of the study population, the knowledge of people about different aspects of malaria (such as clinical symptoms, transmission and prevention) and their practice to prevent illness (such as using mosquito nets, spraying houses). The data were analysed and descriptive statistics (i.e. frequencies, percentages) were used to summarize the results.

Results
The results of this survey showed that 20% (95% CI: 17.36 - 22.24) of households owned at least one mosquito net, whether treated or untreated. Consequently, the use of mosquito nets was considerably low among both children under age five [5.90% (95% CI: 5.14 - 6.66)] and pregnant women [5.70% (95% CI: 3.07 - 8.33)]. Moreover, less than 10% of households reported that the interior walls of their dwelling had been sprayed in the previous year [8.70% (95% CI: 6.09 - 11.31)]. Data also suggest that 63.8% of the participants recognized fever as a sign of malaria, 56.4% reported that mosquito bites cause malaria and about 35% of participants mentioned that the use of mosquito nets could prevent malaria.

Conclusion
Findings from this study indicate that low access to treated nets along with low understanding of the role of nets in malaria prevention are the main barriers to utilization of bed nets. Therefore, the use of insecticide-treated mosquito nets should be encouraged through health education on the importance of the use along with increasing access to it.