bluuebunny/crossref_metadata_2025 huggingface dataset:
Estimating Infrastructural Investment Needs for India
Authors: Sharma Chandan , Bhanumurthy N.R.
Published: May 2011

This article attempts to systemically project the demand and fund requirements for the Indian infrastructure sector up to 2013. In the infrastructure sector transportation (rail, port, air and road), electricity and telecommunication sectors are covered in this study. The analysis is carried out in two stages. In the first stage, long-run linkages between infrastructure variables and income are established by applying the cointegration method. Subsequently, infrastructure demand functions are estimated by using a dynamic ordinary least squares (OLS) (DOLS) technique. In the second stage, by using the estimated infrastructure elasticity to income of variables and IMF’s projected income data, we project sector-wise demand and funding requirements. The results of the analysis indicates that in important sectors like electricity and ports, the government (the Planning Commission) has seriously underestimated future demand, while in the air transport sector, demand seems to be overestimated. Only in telecommunications, are the projections of this study at par with the government’s projections. Overall, we find that the government has underestimated infrastructure needs by at least 7 per cent. Based on these results, we propose the initiation of a set of reforms in the existing financing pattern of infrastructure in the country.
Culture and End-of-Life Care
Authors: Yapp Karleen A.
Published: May 2011

Beneficence is a fundamental concept of medicine, which embodies the notion above all, do no harm. While this principle illustrates the health care professional’s duty to contribute to the patient’s welfare, the principle becomes convoluted when the wishes of the patient directly conflict with that of the physician. The purpose of the study was to determine the degree to which cultural beliefs influence a physician’s decision to introduce the concept of hospice to terminally ill patients. This phenomenological study explored the perceptions of 14 physicians practicing medicine in Mercer County, New Jersey. Analysis of the textural data revealed the following 5 themes: ( a) physician personal perspectives, ( b) physician perspectives on culture, ( c) perspectives on hospice care, ( d) communication with patients, and (e) training and experience.
Bending and Contact Strength of Monolithic Ceramic Materials
Authors: Hegedűsová Lucia , Ceniga Ladislav , Dusza Ján
Published: May 2011

The article deals with the determination of strength of monolithic ceramic materials by mechanical tests, in bending and contact modes, simulated by a four-point bending test and single-cycle contact test using rollers or spheres, respectively. In general, the determination of strength of ceramic materials results from statistical methods, usually represented by the Weibull analysis comprising of the determination of the characteristic strength σ0 and the Weibull modulus m. Accordingly, the characteristic strength σ0,bend and σ0,cont as well as the Weibull moduli mbend and mcont, related to the four-point bending test and the single-cycle contact test using rollers, are determined, respectively. Additionally, the comparison of numerical results of σ0,bend/ σ0,cont, mbend/ mcont confirms the validity of the Fett's theory. Along with this verification and the Weibull analysis for mechanical loading by spheres, a microstructural analysis of strength-degrading defects as fraction origins is performed for the bending and contact modes which induce different types of crack. Finally, the determination of mechanical loading causing material failure and an analysis of parameters of the cracks is also presented. The mechanical tests were applied to monolithic Si3N4 and SiC ceramic materials.
Pregnancy and natalizumab: results of an observational study in 35 accidental pregnancies during natalizumab treatment
Authors: Hellwig Kerstin , Haghikia Aiden , Gold Ralf
Published: May 2011

Background: Natalizumab, a therapeutic monoclonal antibody approved for the treatment of relapsing–remitting multiple sclerosis (RRMS), is recommended to be withdrawn 3 months prior to a planned pregnancy. Our aim was to analyse the safety and impact of natalizumab exposure on course of disease and pregnancy outcome.

Objectives: Prospective follow-up of women with MS who became accidentally pregnant during natalizumab treatment in comparison with pregnancies of women with MS not exposed to disease-modifying treatments (DMT).

Method: 35 women with MS who became accidentally pregnant while treated with natalizumab, and 23 women with MS who became pregnant devoid of any DMT as a control group, were chosen.

Results: All pregnancies except one were followed in a prospective fashion. Of the women exposed to natalizumab during pregnancy, 29 women gave birth to 28 healthy children; one child was born with hexadactyly. Five pregnancies ended in an early miscarriage and one woman decided to undergo an elective termination of pregnancy. MS activity did not rebound during pregnancy or post partum after natalizumab was withdrawn, and no significant differences were observed when compared with the non-DMT-exposed control group.

Conclusion: Our data may support the notion that an elective termination of pregnancy due to natalizumab exposure may not be necessary, but rather requires careful monitoring. Women should still be advised to stop natalizumab in the course of planned pregnancy until more data on long-term outcomes are available.
Advanced Practice Registered Nurse Supply in a Small State: Trends to Inform Policy
Authors: Palumbo Mary Val , Marth Nancy , Rambur Betty
Published: May 2011

This study is a contribution to the small existing pool of state level research on Advanced Practice Registered Nurse (APRN) workforce supply. Data from four biennial surveys of Vermont APRNs from 2003, 2005, 2007, and 2009 ( n = 1,538) were analyzed to produce descriptive statistics of one small state’s APRN demographic, educational, employment, job satisfaction, intention to leave, and practice-setting characteristics. Survey results were then used to identify patterns or trends that existed in the data. There was a marked shift in the employment settings and a decrease time worked as an APRN, despite an aging APRN workforce. There was an increase in the aggregate education level of APRNs; however, the percentage educated at the doctoral level remained flat at 2%. Overall, APRNs were a satisfied segment of the health workforce; however, those intending to leave for dissatisfaction voiced more concern about job stress and less concern about salary and benefits over time. Implications for workforce planning and public policy are discussed.
Cardiovascular pre-participation screening does not distress professional football players
Authors: Solberg EE , Bjørnstad TH , Andersen TE , Ekeberg Ø
Published: May 2011

Background: It has been debated whether cardiovascular screening of athletes creates negative psychological reactions in those being screened. Neither the athletes’ level of distress towards, nor their opinion about screening has actually been examined. Therefore, the aim of this study was to assess the level of distress among Norwegian elite male football players and their experiences of screening.

Methods: After screening, players completed a 10-item scale assessing their experience on a Likert scale. Their level of distress was measured with the intrusion sub-scale of Impact of Event Scale (IES) (7 items) on a six-point scale (grade 0–5). A sum score of ≥19 indicates a clinical stress problem. Twenty-five out of 28 teams, 441 of 591 players (75%, mean age 26 [18–39] years) consented to participate.

Results: Sixty-four percent felt more confident when playing football and 88% were satisfied having completed the screening. The majority (77%) felt a need for the screening and 84% would strongly recommend it to others. Sixteen percent were afraid that the screening result might have consequences for their own health, and 13% were afraid of losing their license to play football. Less than 3% experienced distress (IES ≥ 19).

Conclusions: The majority of the players were satisfied having completed the screening, felt more confident and would recommend it to other players. Only a marginal proportion of the players were distressed by the screening, but were at least as likely to recommend it.
Asymmetrical distribution of atherosclerosis in the carotid artery: identical patterns across age, race, and gender
Authors: Tajik Parvin , Meijer Rudy , Duivenvoorden Raphaël , Peters Sanne AE , Kastelein John J , Visseren Frank J , Crouse John R , Palmer Mike K , Raichlen Joel S , Grobbee Diederick E , Bots Michiel L
Published: May 2011

Background: Small autopsy studies and clinical practice indicated that carotid atherosclerosis develops in an asymmetrical helical pattern coinciding with regions of low shear stress. We investigated the distribution of carotid atherosclerosis as determined by maximum carotid intima-⊟media thickness (CIMT), to assess if we could confirm this atherosclerotic configuration across various populations with different cardiovascular risk. Methods and results: We used the individual baseline CIMT data from 3364 subjects from four recent international multicentre randomized controlled trials in which the carotid artery was systematically examined using the same ultrasound protocol and method to quantify CIMT. For each subject, circumferential information on the maximum CIMT of the left and right carotid arteries was obtained for the common carotid, bifurcation, and internal carotid artery segments. In each segment (common, bifurcation, internal), mixed modelling was used to study the differences in CIMT between angles, sides, gender, age, race, and studies. Each segment showed a different circumferential CIMT pattern. In all segments there were statistically significant differences between maximum CIMT across circumferential angles ( p < 0.001); on average CIMT was highest in the posteromedial wall of the bifurcation and internal carotid segments and in the anterolateral wall of the common carotid segment. This asymmetric circumferential pattern was found to be identical in men and women, in young and old age, in different race groups, and across the studies. Conclusions: We confirmed the asymmetrical helix-like distribution of atherosclerosis in the carotid arteries and expand the evidence by showing that the atherosclerotic configuration is similar across populations with different vascular risks and across gender, age, and race. This has implications for future design of carotid ultrasound studies, as the angle of insonation is an important predictor of maximum CIMT.
Crisis, confidence and collectivity: Responding to the new public leadership challenge
Authors: Brookes Stephen
Published: May 2011

The paper argues that the public sector context in the UK is characterized by a reform that focuses on ‘delivery’ with an unprecedented obsession with measurement. It examines whether the time is right to move from new public management (NPM) to new public leadership (NPL) and supports its argument by reference to literature and a content analysis of the Economic and Social Research Council (ESRC) seminar series papers and the subsequent edited volume ( The New Public Leadership Challenge [NPLC]) that set a public leadership challenge. The paper endorses the view that the focus on NPM has resulted in a culture of ‘counting what can be counted rather than what counts’ (McKee, 2004) and proposes a frame of reference that has potential for supporting the development and evaluation of new public leadership.
Methodological crises and contextual solutions: An ethnomethodologically informed approach to understanding leadership
Authors: Iszatt-White Marian
Published: May 2011

The view of context as something which restricts the range of research but is not an integral part of that which is being researched is implicit in many traditional approaches to leadership theory development. Some recent approaches have sought to address this by taking a more directly situated approach to the understanding of leadership, and by paying close attention to the practical accomplishment of leadership work within a given context. It is the premise of this paper, however, that there is still much work to be done in this important aspect of leadership research, and that considering this from a specifically methodological perspective may have a contribution to make. In support of this argument, the paper adopts the ethnomethodological notion of ‘mutual elaboration’ to explore leadership practices as irreducibly events in a social order. By placing context centre stage, and explicating the practice of leadership as an inherently contextual performance, it offers a relatively untapped approach to the understanding of leadership work and suggests the value of this approach in providing a rich resource of data for the development of innovative theory.
Imagining Alternative Visions of Justice: An Exploration of the Controversy Surrounding Stirling Lee’s Depictions of Justitia in Nineteenth-Century Liverpool
Authors: Mulcahy Linda
Published: May 2011

In recent years there has been a burgeoning interest in the relationship between law, art and politics. New work in the field encourages us to explore the ways in which art can pose a threat to the supposed rationality of modern law by appealing to imagination and emotion. This article explores these general themes with reference to a specific controversy about a series of bas relief sculptures depicting Justitia which were placed on the side of what was arguably the most spectacular law court to be built in England in the nineteenth century. Although this episode has been explored by art historians, hardly any attention has been drawn to what the episode reveals about the political work that art was, and is, expected to undertake on behalf of the elite and legal establishment. This article attempts to bridge that gap by exploring the extent to which the creator of public artwork, so often a handmaiden of the State when helping us to imagine justice, is also capable of presenting us with subversive images of our Goddess which can, and should, disturb us.
Justice at Trial: Dramatic Ironies of the Postracial State
Authors: Sanders Rachel
Published: May 2011

This article challenges the celebration of Sonia Sotomayor’s confirmation to the Supreme Court as the realization of the American dream and Court diversity in a colorblind era. It analyzes the epistemological compromises Sotomayor had to make in order to comply with what I call the prevailing legal metanarrative of postracial impartiality. Prime among these compromises was Sotomayor’s retraction of her prior critique of the disembodied and de-raced perspective this legal metanarrative presumes. I read the confirmation hearing and its aftermath as a performative ritual in which both her interrogators and Sotomayor herself restore the normative hegemony of the ideal of colorblind objectivity. I argue that this ideal functions ideologically to maintain both normative and material white and masculine privilege, precisely as state decisionmaking institutions become increasingly sexually and ethnically diverse. I draw out the dramatic ironies of the participants’ strategic disavowals – Sotomayor’s denial of the roles personal experience and empathy play in judgment, and state officials’ denial of the persistent material relevance of race in the contemporary United States. I show that trading in these rhetorics has pernicious, and paradoxical, repercussions for the national racial order.
Novel associations between activating killer-cell immunoglobulin-like receptor genes and childhood leukemia
Authors: Almalte Zaema , Samarani Suzanne , Iannello Alexandre , Debbeche Olfa , Duval Michel , Infante-Rivard Claire , Amre Devendra K. , Sinnett Daniel , Ahmad Ali
Published: May 2011

Acute lymphoblastic leukemia of pre-B cells (pre-B ALL) is the most frequent form of leukemia affecting children in Western countries. Evidence is accumulating that genetic factors play an important role in conferring susceptibility/resistance to leukemia in children. In this regard, activating killer-cell immunoglobulin-like receptor (KIR) genes are of particular interest. Humans may inherit different numbers of the 6 distinct activating KIR genes. Little is known about the impact of this genetic variation on the innate susceptibility or resistance of humans to the development of B-ALL. We addressed this issue by performing a case-control study in Canadian children of white origin. Our results show that harboring activating KIR genes is associated with reduced risk for developing B-ALL in these children. Of the 6 activating KIR genes, KIR2DS2 was maximally associated with decreased risk for the disease (P = 1.14 × 10−7). Furthermore, our results showed that inheritance of a higher number of activating KIR genes was associated with significant reductions in risk for ALL in children. These results were also consistent across different ALL phenotypes, which included children with pre-T cell ALL. Our study provides novel insights concerning the pathogenesis of childhood leukemia in white children and has implications for the development of new immunotherapies for this cancer.
Musashi 2 is a regulator of the HSC compartment identified by a retroviral insertion screen and knockout mice
Authors: de Andrés-Aguayo Luisa , Varas Florencio , Kallin Eric M. , Infante José F. , Wurst Wolfgang , Floss Thomas , Graf Thomas
Published: May 2011

We used a retroviral integration screen to search for novel genes that regulate HSC function. One of the genes that conferred HSC dominance when overexpressed due to an adjacent retroviral insertion was Musashi 2 (Msi2), an RNA-binding protein that can act as a translational inhibitor. A gene-trap mouse model that inactivates the gene shows that Msi2 is more highly expressed in long-term (LT) and short-term (ST) HSCs, as well as in lymphoid myeloid primed progenitors (LMPPs), but much less in intermediate progenitors and mature cells. Mice lacking Msi2 are fully viable for up to a year or more, but exhibit severe defects in primitive precursors, most significantly a reduction in the number of ST-HSCs and LMPPs and a decrease in leukocyte numbers, effects that are exacerbated with age. Cell-cycle and gene-expression analyses suggest that the main hematopoietic defect in Msi2-defective mice is the decreased proliferation capacity of ST-HSCs and LMPPs. In addition, HSCs lacking Msi2 are severely impaired in competitive repopulation experiments, being overgrown by wild-type cells even when mutant cells were provided in excess. Our data indicate that Msi2 maintains the stem cell compartment mainly by regulating the proliferation of primitive progenitors downstream of LT-HSCs.
The only proposed T-cell epitope derived from the TEL-AML1 translocation is not naturally processed
Authors: Popović Jelena , Li Liang-Ping , Kloetzel Peter Michael , Leisegang Matthias , Uckert Wolfgang , Blankenstein Thomas
Published: May 2011

Adoptive therapy with T-cell receptor (TCR)–engineered T cells is a promising approach in cancer treatment. While usage of T cells specific for tumor-associated antigens (TAAs) can lead to serious side effects because of autoimmunity, targeting true tumor-specific mutations, such as the products of translocations in leukemias, should reduce such a risk. A potentially ideal target might be the chimeric protein TEL-AML1, which results from the chromosomal translocation 12;21 and represents the most common fusion gene in childhood B-cell precursor acute lymphoblastic leukemia (BCP-ALL). Within the fusion region of TEL-AML1, a single epitope has been described by reverse immunology as immunogenic in HLA-A*0201 restriction settings. As a potential source of TCRs specific for this TEL-AML1 epitope, we have used mice expressing a human TCR-αβ repertoire and human MHC class I. Surprisingly, we have found that, although a specific functional CD8+ T-cell response against this peptide could be evoked, the described epitope was in fact not endogenously processed. Analyses done with a potent antigen-presenting cell line, as well as with purified human proteasomes, support the conclusion that this peptide cannot be proposed as a potential target in immunotherapy of ALL in HLA-A*0201-restricted fashion.
Missense mutations in PML-RARA are critical for the lack of responsiveness to arsenic trioxide treatment
Authors: Goto Emi , Tomita Akihiro , Hayakawa Fumihiko , Atsumi Akihide , Kiyoi Hitoshi , Naoe Tomoki
Published: May 2011

Arsenic trioxide (As2O3) is a highly effective treatment for patients with refractory/relapsed acute promyelocytic leukemia (APL), but resistance to As2O3 has recently been seen. In the present study, we report the findings that 2 of 15 patients with refractory/relapsed APL treated with As2O3 were clinically As2O3 resistant. Leukemia cells from these 2 patients harbored missense mutations in promyelocytic leukemia gene–retinoic acid receptor-α gene (PML-RARA) transcripts, resulting in amino acid substitutions of A216V and L218P in the PML B2 domain. When wild-type or mutated PML-RARA (PR-WT and PR-B/L-mut, respectively) were overexpressed in HeLa cells, immunoblotting showed SUMOylated and/or oligomerized protein bands in PR-WT but not in PR-B/L-mut after As2O3 treatment. Protein-localization analysis indicated that PR-WT in the soluble fraction was transferred to the insoluble fraction after treatment with As2O3, but PR-B/L-mut was stably detected in fractions both with and without As2O3. Immunofluorescent microscopy analysis showed PR-WT localization as a microgranular pattern in the cytoplasm without As2O3 and as a macrogranular pattern with As2O3. PR-B/L-mut was diffusely observed in the cytoplasm with and without As2O3. Nearly identical localization patterns were observed in patients' primary cells. Therefore, B2 domain mutations may play an important role in aberrant molecular responses to As2O3 and may be critical for As2O3 resistance in APL.
High success rate of hematopoietic cell transplantation regardless of donor source in children with very high-risk leukemia
Authors: Leung Wing , Campana Dario , Yang Jie , Pei Deqing , Coustan-Smith Elaine , Gan Kwan , Rubnitz Jeffrey E. , Sandlund John T. , Ribeiro Raul C. , Srinivasan Ashok , Hartford Christine , Triplett Brandon M. , Dallas Mari , Pillai Asha , Handgretinger Rupert , Laver Joseph H. , Pui Ching-Hon
Published: May 2011

We evaluated 190 children with very high-risk leukemia, who underwent allogeneic hematopoietic cell transplantation in 2 sequential treatment eras, to determine whether those treated with contemporary protocols had a high risk of relapse or toxic death, and whether non–HLA-identical transplantations yielded poor outcomes. For the recent cohorts, the 5-year overall survival rates were 65% for the 37 patients with acute lymphoblastic leukemia and 74% for the 46 with acute myeloid leukemia; these rates compared favorably with those of earlier cohorts (28%, n = 57; and 34%, n = 50, respectively). Improvement in the recent cohorts was observed regardless of donor type (sibling, 70% vs 24%; unrelated, 61% vs 37%; and haploidentical, 88% vs 19%), attributable to less infection (hazard ratio [HR] = 0.12; P = .005), regimen-related toxicity (HR = 0.25; P = .002), and leukemia-related death (HR = 0.40; P = .01). Survival probability was dependent on leukemia status (first remission vs more advanced disease; HR = 0.63; P = .03) or minimal residual disease (positive vs negative; HR = 2.10; P = .01) at the time of transplantation. We concluded that transplantation has improved over time and should be considered for all children with very high-risk leukemia, regardless of matched donor availability.
Anti-CD45 pretargeted radioimmunotherapy using bismuth-213: high rates of complete remission and long-term survival in a mouse myeloid leukemia xenograft model
Authors: Pagel John M. , Kenoyer Aimee L. , Bäck Tom , Hamlin Donald K. , Wilbur D. Scott , Fisher Darrell R. , Park Steven I. , Frayo Shani , Axtman Amanda , Orgun Nural , Orozco Johnnie , Shenoi Jaideep , Lin Yukang , Gopal Ajay K. , Green Damian J. , Appelbaum Frederick R. , Press Oliver W.
Published: May 2011

Pretargeted radioimmunotherapy (PRIT) using an anti-CD45 antibody (Ab)–streptavidin (SA) conjugate and DOTA-biotin labeled with β-emitting radionuclides has been explored as a strategy to decrease relapse and toxicity. α-emitting radionuclides exhibit high cytotoxicity coupled with a short path length, potentially increasing the therapeutic index and making them an attractive alternative to β-emitting radionuclides for patients with acute myeloid leukemia. Accordingly, we have used 213Bi in mice with human leukemia xenografts. Results demonstrated excellent localization of 213Bi-DOTA-biotin to tumors with minimal uptake into normal organs. After 10 minutes, 4.5% ± 1.1% of the injected dose of 213Bi was delivered per gram of tumor. α-imaging demonstrated uniform radionuclide distribution within tumor tissue 45 minutes after 213Bi-DOTA-biotin injection. Radiation absorbed doses were similar to those observed using a β-emitting radionuclide (90Y) in the same model. We conducted therapy experiments in a xenograft model using a single-dose of 213Bi-DOTA-biotin given 24 hours after anti-CD45 Ab-SA conjugate. Among mice treated with anti-CD45 Ab-SA conjugate followed by 800 μCi of 213Bi- or 90Y-DOTA-biotin, 80% and 20%, respectively, survived leukemia-free for more than 100 days with minimal toxicity. These data suggest that anti-CD45 PRIT using an α-emitting radionuclide may be highly effective and minimally toxic for treatment of acute myeloid leukemia.
Characterization of the expression, promoter activity and molecular architecture of fibin
Authors: Lakner Johannes , Seyer Christian , Hermsdorf Thomas , Schöneberg Torsten
Published: May 2011

Background

Fibin was initially discovered as a secreted signal molecule essential for pectoral fin bud initiation in zebrafish. Currently, there is little information about the molecular architecture and biological relevance of fibin in humans and other mammals.

Results

Fibin is expressed in cerebellum, skeletal muscle and many other embryonic and adult mouse tissues suggesting not only a role during embryonic development but also in adult functions. A 2.5-kbp genomic sequence fragment upstream of the coding sequence is sufficient to drive and regulate fibin expression through stimulation by glucocorticoids, activators of the protein kinase C signalling pathways and manganese ions. Fibin is an evolutionarily conserved protein, carries a cleavable signal peptide (amino acids 1-18) and is glycosylated at Asn30. The two conserved cysteines participate in intermolecular disulfide bond and multimer formation. Although fibin displays all features of a secretory protein, it is mostly retained in the endoplasmic reticulum when heterologously expressed.

Conclusion

Fibin is functionally relevant during embryogenesis and adult life. Its expression is regulated by a number of cellular signalling pathways and the protein is routed via the secretory pathway. However, proper secretion presumably requires an unknown covalently-linked or associated co-factor.
Protein coalitions in a core mammalian biochemical network linked by rapidly evolving proteins
Authors: Ainali Chrysanthi , Simon Michelle , Freilich Shiri , Espinosa Octavio , Hazelwood Lee , Tsoka Sophia , Ouzounis Christos A , Hancock John M
Published: May 2011

Background

Cellular ATP levels are generated by glucose-stimulated mitochondrial metabolism and determine metabolic responses, such as glucose-stimulated insulin secretion (GSIS) from the β-cells of pancreatic islets. We describe an analysis of the evolutionary processes affecting the core enzymes involved in glucose-stimulated insulin secretion in mammals. The proteins involved in this system belong to ancient enzymatic pathways: glycolysis, the TCA cycle and oxidative phosphorylation.

Results

We identify two sets of proteins, or protein coalitions, in this group of 77 enzymes with distinct evolutionary patterns. Members of the glycolysis, TCA cycle, metabolite transport, pyruvate and NADH shuttles have low rates of protein sequence evolution, as inferred from a human-mouse comparison, and relatively high rates of evolutionary gene duplication. Respiratory chain and glutathione pathway proteins evolve faster, exhibiting lower rates of gene duplication. A small number of proteins in the system evolve significantly faster than co-pathway members and may serve as rapidly evolving adapters, linking groups of co-evolving genes.

Conclusions

Our results provide insights into the evolution of the involved proteins. We find evidence for two coalitions of proteins and the role of co-adaptation in protein evolution is identified and could be used in future research within a functional context.
Analysis of common bean expressed sequence tags identifies sulfur metabolic pathways active in seed and sulfur-rich proteins highly expressed in the absence of phaseolin and major lectins
Authors: Yin Fuqiang , Pajak Agnieszka , Chapman Ralph , Sharpe Andrew , Huang Shangzhi , Marsolais Frédéric
Published: May 2011

Background

A deficiency in phaseolin and phytohemagglutinin is associated with a near doubling of sulfur amino acid content in genetically related lines of common bean (Phaseolus vulgaris), particularly cysteine, elevated by 70%, and methionine, elevated by 10%. This mostly takes place at the expense of an abundant non-protein amino acid, S-methyl-cysteine. The deficiency in phaseolin and phytohemagglutinin is mainly compensated by increased levels of the 11S globulin legumin and residual lectins. Legumin, albumin-2, defensin and albumin-1 were previously identified as contributing to the increased sulfur amino acid content in the mutant line, on the basis of similarity to proteins from other legumes.

Results

Profiling of free amino acid in developing seeds of the BAT93 reference genotype revealed a biphasic accumulation of gamma-glutamyl-S-methyl-cysteine, the main soluble form of S-methyl-cysteine, with a lag phase occurring during storage protein accumulation. A collection of 30,147 expressed sequence tags (ESTs) was generated from four developmental stages, corresponding to distinct phases of gamma-glutamyl-S-methyl-cysteine accumulation, and covering the transitions to reserve accumulation and dessication. Analysis of gene ontology categories indicated the occurrence of multiple sulfur metabolic pathways, including all enzymatic activities responsible for sulfate assimilation, de novo cysteine and methionine biosynthesis. Integration of genomic and proteomic data enabled the identification and isolation of cDNAs coding for legumin, albumin-2, defensin D1 and albumin-1A and -B induced in the absence of phaseolin and phytohemagglutinin. Their deduced amino acid sequences have a higher content of cysteine than methionine, providing an explanation for the preferential increase of cysteine in the mutant line.

Conclusion

The EST collection provides a foundation to further investigate sulfur metabolism and the differential accumulation of sulfur amino acids in seed of common bean. Identification of sulfur-rich proteins whose levels are elevated in seed lacking phaseolin and phytohemagglutinin and sulfur metabolic genes may assist the improvement of protein quality.
The crystal structure of alanine racemase from Streptococcus pneumoniae, a target for structure-based drug design
Authors: Im Hookang , Sharpe Miriam L , Strych Ulrich , Davlieva Milya , Krause Kurt L
Published: May 2011

Background

Streptococcus pneumoniae is a globally important pathogen. The Gram-positive diplococcus is a leading cause of pneumonia, otitis media, bacteremia, and meningitis, and antibiotic resistant strains have become increasingly common over recent years.Alanine racemase is a ubiquitous enzyme among bacteria and provides the essential cell wall precursor, D-alanine. Since it is absent in humans, this enzyme is an attractive target for the development of drugs against S. pneumoniae and other bacterial pathogens.

Results

Here we report the crystal structure of alanine racemase from S. pneumoniae (AlrSP). Crystals diffracted to a resolution of 2.0 Å and belong to the space group P3121 with the unit cell parameters a = b = 119.97 Å, c = 118.10 Å, α = β = 90° and γ = 120°. Structural comparisons show that AlrSP shares both an overall fold and key active site residues with other bacterial alanine racemases. The active site cavity is similar to other Gram positive alanine racemases, featuring a restricted but conserved entryway.

Conclusions

We have solved the structure of AlrSP, an essential step towards the development of an accurate pharmacophore model of the enzyme, and an important contribution towards our on-going alanine racemase structure-based drug design project. We have identified three regions on the enzyme that could be targeted for inhibitor design, the active site, the dimer interface, and the active site entryway.
Dexamethasone inhibits the Nox-dependent ROS production via suppression of MKP-1-dependent MAPK pathways in activated microglia
Authors: Huo Yingqian , Rangarajan Parakalan , Ling Eng-Ang , Dheen S Thameem
Published: May 2011

Background

Nox-2 (also known as gp91phox), a subunit component of NADPH oxidases, generates reactive oxygen species (ROS). Nox-dependent ROS generation and nitric oxide (NO) release by microglia have been implicated in a variety of diseases in the central nervous system. Dexamethasone (Dex) has been shown to suppress the ROS production, NO release and inflammatory reaction of activated microglial cells. However, the underlying mechanisms remain unclear.

Results

The present study showed that the increased ROS production and NO release in activated BV-2 microglial cells by LPS were associated with increased expression of Nox-2 and iNOS. Dex suppressed the upregulation of Nox-2 and iNOS, as well as the subsequent ROS production and NO synthesis in activated BV-2 cells. This inhibition caused by Dex appeared to be mediated by upregulation of MAPK phosphatase-1 (MKP-1), which antagonizes the activity of mitogen-activated protein kinases (MAPKs). Dex induced-suppression of Nox-2 and -upregulation of MKP-1 was also evident in the activated microglia from corpus callosum of postnatal rat brains. The overexpression of MKP-1 or inhibition of MAPKs (by specific inhibitors of JNK and p38 MAPKs), were found to downregulate the expression of Nox-2 and iNOS and thereby inhibit the synthesis of ROS and NO in activated BV-2 cells. Moreover, Dex was unable to suppress the LPS-induced synthesis of ROS and NO in BV-2 cells transfected with MKP-1 siRNA. On the other hand, knockdown of Nox-2 in BV-2 cells suppressed the LPS-induced ROS production and NO release.

Conclusion

In conclusion, it is suggested that downregulation of Nox-2 and overexpression of MKP-1 that regulate ROS and NO may form the potential therapeutic strategy for the treatment of neuroinflammation in neurodegenerative diseases.
Characterization and analysis of the cotton cyclopropane fatty acid synthase family and their contribution to cyclopropane fatty acid synthesis
Authors: Yu Xiao-Hong , Rawat Richa , Shanklin John
Published: May 2011

Background

Cyclopropane fatty acids (CPA) have been found in certain gymnosperms, Malvales, Litchi and other Sapindales. The presence of their unique strained ring structures confers physical and chemical properties characteristic of unsaturated fatty acids with the oxidative stability displayed by saturated fatty acids making them of considerable industrial interest. While cyclopropenoid fatty acids (CPE) are well-known inhibitors of fatty acid desaturation in animals, CPE can also inhibit the stearoyl-CoA desaturase and interfere with the maturation and reproduction of some insect species suggesting that in addition to their traditional role as storage lipids, CPE can contribute to the protection of plants from herbivory.

Results

Three genes encoding cyclopropane synthase homologues GhCPS1, GhCPS2 and GhCPS3 were identified in cotton. Determination of gene transcript abundance revealed differences among the expression of GhCPS1, 2 and 3 showing high, intermediate and low levels, respectively, of transcripts in roots and stems; whereas GhCPS1 and 2 are both expressed at low levels in seeds. Analyses of fatty acid composition in different tissues indicate that the expression patterns of GhCPS1 and 2 correlate with cyclic fatty acid (CFA) distribution. Deletion of the N-terminal oxidase domain lowered GhCPS's ability to produce cyclopropane fatty acid by approximately 70%. GhCPS1 and 2, but not 3 resulted in the production of cyclopropane fatty acids upon heterologous expression in yeast, tobacco BY2 cell and Arabidopsis seed.

Conclusions

In cotton GhCPS1 and 2 gene expression correlates with the total CFA content in roots, stems and seeds. That GhCPS1 and 2 are expressed at a similar level in seed suggests both of them can be considered potential targets for gene silencing to reduce undesirable seed CPE accumulation. Because GhCPS1 is more active in yeast than the published Sterculia CPS and shows similar activity when expressed in model plant systems, it represents a strong candidate gene for CFA accumulation via heterologous expression in production plants.
Introduction of an electronic monitoring system for monitoring compliance with Moments 1 and 4 of the WHO "My 5 Moments for Hand Hygiene" methodology
Authors: Cheng Vincent CC , Tai Josepha WM , Ho Sara KY , Chan Jasper FW , Hung Kwan Ngai , Ho Pak Leung , Yuen Kwok Yung
Published: May 2011

Background

MedSense is an electronic hand hygiene compliance monitoring system that provides Infection Control Practitioners with continuous access to hand hygiene compliance information by monitoring Moments 1 and 4 of the WHO "My 5 Moments for Hand Hygiene" guidelines. Unlike previous electronic monitoring systems, MedSense operates in open cubicles with multiple beds and does not disrupt existing workflows.

Methods

This study was conducted in a 6-bed neurosurgical intensive care unit with technical development and evaluation phases. Healthcare workers (HCWs) wore an electronic device in the style of an identity badge to detect hand hygiene opportunities and compliance. We compared the compliance determined by the system and an infection control nurse. At the same time, the system assessed compliance by time of day, day of week, work shift, professional category of HCWs, and individual subject, while the workload of HCWs was monitored by measuring the amount of time they spent in patient zones.

Results

During the three-month evaluation phase, the system identified 13,694 hand hygiene opportunities from 17 nurses, 3 physiotherapists, and 1 healthcare assistant, resulting in an overall compliance of 35.1% for the unit. The per-indication compliance for Moment 1, 4, and simultaneous 1 and 4 were 21.3% (95%CI: 19.0, 23.6), 39.6% (95%CI: 37.3, 41.9), and 49.2% (95%CI: 46.6, 51.8), respectively, and were all statistically significantly different (p < 0.001). In the four 20-minute sessions when hand hygiene was monitored concurrently by the system and infection control nurse, the compliance were 88.9% and 95.6% respectively (p = 0.34), and the activity indices were 11.1 and 12.9 opportunities per hour, respectively. The hours from 12:00 to 14:00 had a notably lower compliance (21.3%, 95%CI: 17.2, 25.3) than nearly three quarters of the other periods of the day (p < 0.001). Nurses who used shared badges had significantly (p < 0.01) lower compliance (23.7%, 95%CI: 17.8, 29.6) than both the registered nurses (36.1%, 95%CI: 34.2, 37.9) and nursing officers (34.0%, 95%CI: 31.1, 36.9) who used named badges.

Conclusion

MedSense provides an unobtrusive and objective measurement of hand hygiene compliance. The information is important for staff training by the infection control team and allocation of manpower by hospital administration.
Genetic polymorphisms in folate pathway enzymes, DRD4 and GSTM1 are related to temporomandibular disorder
Authors: Aneiros-Guerrero Angel , Lendinez Ana M , Palomares Arturo R , Perez-Nevot Beatriz , Aguado Lidia , Mayor-Olea Alvaro , Ruiz-Galdon Maximiliano , Reyes-Engel Armando
Published: May 2011

Background

Temporomandibular disorder (TMD) is a multifactorial syndrome related to a critical period of human life. TMD has been associated with psychological dysfunctions, oxidative state and sexual dimorphism with coincidental occurrence along the pubertal development. In this work we study the association between TMD and genetic polymorphisms of folate metabolism, neurotransmission, oxidative and hormonal metabolism. Folate metabolism, which depends on genes variations and diet, is directly involved in genetic and epigenetic variations that can influence the changes of last growing period of development in human and the appearance of the TMD.

Methods

A case-control study was designed to evaluate the impact of genetic polymorphisms above described on TMD. A total of 229 individuals (69% women) were included at the study; 86 were patients with TMD and 143 were healthy control subjects. Subjects underwent to a clinical examination following the guidelines by the Research Diagnostic Criteria for Temporomandibular Disorders (RDC/TMD). Genotyping of 20 Single Nucleotide Polymorphisms (SNPs), divided in two groups, was performed by multiplex minisequencing preceded by multiplex PCR. Other seven genetic polymorphisms different from SNPs (deletions, insertions, tandem repeat, null genotype) were achieved by a multiplex-PCR. A chi-square test was performed to determine the differences in genotype and allelic frequencies between TMD patients and healthy subjects. To estimate TMD risk, in those polymorphisms that shown significant differences, odds ratio (OR) with a 95% of confidence interval were calculated.

Results

Six of the polymorphisms showed statistical associations with TMD. Four of them are related to enzymes of folates metabolism: Allele G of Serine Hydoxymethyltransferase 1 (SHMT1) rs1979277 (OR = 3.99; 95%CI 1.72, 9.25; p = 0.002), allele G of SHMT1 rs638416 (OR = 2.80; 95%CI 1.51, 5.21; p = 0.013), allele T of Methylentetrahydrofolate Dehydrogenase (MTHFD) rs2236225 (OR = 3.09; 95%CI 1.27, 7.50; p = 0.016) and allele A of Methionine Synthase Reductase (MTRR) rs1801394 (OR = 2.35; 95CI 1.10, 5.00; p = 0.037). An inflammatory oxidative stress enzyme, Gluthatione S-Tranferase Mu-1(GSTM1), null allele (OR = 2.21; 95%CI 1.24, 4.36; p = 0.030) and a neurotransmission receptor, Dopamine Receptor D4 (DRD4), long allele of 48 bp-repeat (OR = 3.62; 95%CI 0.76, 17.26; p = 0.161).

Conclusions

Some genetic polymorphisms related to folates metabolism, inflammatory oxidative stress, and neurotransmission responses to pain, has been significantly associated to TMD syndrome
Selected AGXT gene mutations analysis provides a genetic diagnosis in 28% of Tunisian patients with primary hyperoxaluria
Authors: Mbarek Ibtihel Benhaj , Abroug Saoussen , Omezzine Asma , Zellama Dorsaf , Achour Abdellatif , Harbi Abdelaziz , Bouslama Ali
Published: May 2011

Background

Primary hyperoxaluria type I (PH1) is a rare genetic disorder characterized by allelic and clinical heterogeneity. Four mutations (G170R, 33_34insC, I244T and F152I) account for more than 50% of PH1 alleles and form the basis for diagnostic genetic screening for PH1. We aimed to analyze the prevalence of these specific mutations causing PH1, and to provide an accurate tool for diagnosis of presymptomatic patients as well as for prenatal diagnosis in the affected families.

Methods

Polymerase chain reaction/Restriction Fragment Length Polymorphism, were used to detect the four mutations in the AGXT gene in DNA samples from 57 patients belonging to 40 families.

Results

Two mutations causing PH1 were detected in 24 patients (42.1%), with a predominance of the I244T mutation (68% of patients) and 33_34insC (in the remaining 32%). In 92% of cases, mutated alleles were in homozygous state.

The presented clinical features were similar for the two mutations. The age of onset was heterogeneous with a higher frequency of the pediatric age. In 58.3% of cases, the presentation corresponded to advanced renal disease which occurred early (< 5 years) in the two mutations. In adolescents, only the I244T mutation was detected (41.1%). I244T and 33_34insC mutations were observed in adult patients, with 17.6% and 12.5% respectively.

Conclusion

Limited mutation analysis can provide a useful first line investigation for PH1. I244T and 33_34insC presented 28.2% of identified mutations causing disease in our cohort. This identification could provide an accurate tool for prenatal diagnosis in the affected families, for genetic counselling and for detection of presymptomatic individuals.
Overexpression of eIF-5A2 in mice causes accelerated organismal aging by increasing chromosome instability
Authors: Chen Muhan , Huang Jian-Dong , Deng Hong Kui , Dong Suisui , Deng Wen , Tsang Sze Lan , Huen Michael SY , Chen Leilei , Zan Tong , Zhu Gui-Xia , Guan Xin-Yuan
Published: May 2011

Background

Amplification of 3q26 is one of the most frequent genetic alterations in many human malignancies. Recently, we isolated a novel oncogene eIF-5A2 within the 3q26 region. Functional study has demonstrated the oncogenic role of eIF-5A2 in the initiation and progression of human cancers. In the present study, we aim to investigate the physiological and pathological effect of eIF-5A2 in an eIF-5A2 transgenic mouse model.

Methods

An eIF-5A2 transgenic mouse model was generated using human eIF-5A2 cDNA. The eIF-5A2 transgenic mice were characterized by histological and immunohistochemistry analyses. The aging phenotypes were further characterized by wound healing, bone X-ray imaging and calcification analysis. Mouse embryo fibroblasts (MEF) were isolated to further investigate molecular mechanism of eIF-5A2 in aging.

Results

Instead of resulting in spontaneous tumor formation, overexpression of eIF-5A2 accelerated the aging process in adult transgenic mice. This included decreased growth rate and body weight, shortened life span, kyphosis, osteoporosis, delay of wound healing and ossification. Investigation of the correlation between cellular senescence and aging showed that cellular senescence is not required for the aging phenotypes in eIF-5A2 mice. Interestingly, we found that activation of eIF-5A2 repressed p19 level and therefore destabilized p53 in transgenic mouse embryo fibroblast (MEF) cells. This subsequently allowed for the accumulation of chromosomal instability, such as errors in cell dividing during metaphase and anaphase. Additionally, a significantly increase in number of aneuploidy cells (p < 0.05) resulted from an increase in the incidences of misaligned and lagging chromosomal materials, anaphase bridges, and micronuclei in the transgenic mice.

Conclusion

These observations suggest that eIF-5A2 mouse models could accelerate organismal aging by increasing chromosome instability.