bluuebunny/crossref_metadata_2025 huggingface dataset:
Effects of gasoline–diesel and n-butanol–diesel blends on performance and emissions of an automotive direct-injection diesel engine
Authors: Valentino Gerardo , Corcione Felice E , Iannuzzi Stefano E
Published: May 2012

In the present paper, results of an experimental investigation carried out in a modern diesel engine running at different operating conditions and fuelled with blends of gasoline–diesel and n-butanol–diesel, are reported. The exploration strategy was focused on the management of injection pressure and timing to achieve a condition in which the whole amount of fuel was delivered before ignition. The aim of the paper is to evaluate the effects of fuel blends, which have low cetane number (CN) and are more resistant to auto-ignition than diesel fuel, on performance and engine-out emissions. Blends were mixed by the baseline diesel (D00) with 40% of commercial unleaded gasoline (G40) and 40% of n-butanol (B40). Fuel consumption and engine-out gaseous and smoke emissions from fuel blends were measured and compared to the neat diesel fuel. The investigation was performed on a turbocharged, water-cooled, direct-injection diesel engine, equipped with a common-rail injection system. The engine equipment included an exhaust gas recirculation system controlled by an external driver, a piezo-quartz pressure transducer to detect the in-cylinder pressure signal and a current probe to acquire the energizing current to the injectors. Engine tests were carried out at two engine operating conditions: 2000 r/min at 0.5 MPa and 2500 r/min at 0.8 MPa brake mean effective pressure, exploring the effect of start of injection, O2 concentration at intake and injection pressure on combustion behaviour and engine-out emissions.

Taking advantages of the higher resistance of G40 and B40 to auto-ignition, it was possible to extend the range in which a partial premixed combustion was achieved. The management of injection pressure, O2 concentration at intake and injection timing allowed partial premixed combustion to be obtained by extending the ignition delay, both for diesel fuel and blends. The longer ignition delay and the better mixing before combustion made more advanced injection timings, which reduced smoke and nitrogen oxide emissions, possible. The joint effect of higher resistance to auto-ignition and higher volatility of n-butanol and gasoline improved the emissions of the blends compared to the neat diesel fuel, with a low penalty on fuel consumption.
Implementing the early childhood development teacher training framework in Uganda: Gains and challenges
Authors: Ejuu Godfrey
Published: April 2012

Training of quality early childhood development (ECD) teachers is paramount in ensuring quality ECD service provision. This exploratory study focuses on the gains and challenges met in the implementation of the Uganda ECD teacher training framework. Data were obtained using questionnaires and interviews from principals and tutors of ECD teacher training institutions ( n = 106) who participated in a framework familiarization workshop. Results indicated some gains in use of the framework, while other areas still need more support for it to be effectively implemented. Major challenges were found in institutional management and administrative set ups, tutor competencies, and trainee assessment. The article concludes with specific recommendations for technical assistance to promote effective implementation of framework so as to produce better ECD teachers in Uganda.
The role of joint attention in social communication and play among infants
Authors: Shin Minsun
Published: April 2012

Joint attention enables infants to communicate with adults as well as with each other, sharing what is in their minds. Yet, communicative competence and joint attention between infant peers have received little attention in the literature. The purpose of this qualitative study was to explore how infants under the age of two within a childcare setting communicate with each other through joint attention and social understanding during daily interactions. Findings indicated that infants utilized various communicative means, intentional pointing, and joint attention in order to share their experience with each other, develop social understanding, and enjoy social joint play. This study also suggests that conflicts between infants can be a fundamental vehicle for developing social understanding and joint play activity.
Academic integrity in action research
Authors: Levin Morten
Published: May 2012

This article attends to how claims for rigor and relevance can be met in action research (AR). High degree of relevance emanates from the focus on solving pertinent problems. Academic integrity is introduced as the issue that is essential for shaping research of high rigor from AR, and it is conceptualized as the combination of formal (substantive and methodological) research skills, strategic political capacity, and the ethical and moral stature necessary to argue and act for seeking the best possible understanding (truth). The point of departure is a discussion of the critique that has been raised of AR, and the article suggests that through a discussion of what is the essence of social science research, the solution may be found in the formation process ‘Bildung’ of action researchers. The final sections of the article introduce four factors that would support high rigor in writing scientific texts for communicating research findings: research partnering; controlling biases; standardized methods; and alternative explanations. These factors would then secure trustworthy rigorous research and proper dissertations.
Technical Factors Affecting the Accuracy of Bedside IVC Filter Placement Using Intravascular Ultrasound
Authors: Hodgkiss-Harlow Kelley , Back Martin R. , Brumberg Robert , Armstrong Paul , Shames Murray , Johnson Brad , Bandyk Dennis F.
Published: April 2012

Purpose: To compare the accuracy of inferior vena cava (IVC) filter placement using a bedside technique guided by intravascular ultrasound (IVUS) with a concurrent experience of filter deployment with fluoroscopic venogram imaging. Methods: From November 2006 to December 2009, 195 consecutive IVC filters were placed to prevent pulmonary embolism in 120 high-risk patients without lower limb deep vein thrombosis (DVT) and 75 patients with DVT and anticoagulation contraindications. Filter insertion techniques included bedside IVUS-guided (n = 97) and fluoroscopic-guided (n = 98) procedures. Before mid-2008, 2 bedside IVUS-guided protocols were used evolving from a single-puncture, pullback technique (n = 48), in which the measured distance from the venous access site to the IVC landing zone then allowed a calibrated reinsertion of a 7F delivery sheath and filter deployment. After mid-2008, a single puncture 8F sheath technique (n = 48) using IVUS to position the delivery sheath tip within the IVC landing zone without catheter or sheath measurement or reinsertion was used. Venous access was via the right femoral (84 IVUS and 56 fluoroscopy), left femoral (10 IVUS and 16 fluoroscopy), or right internal jugular vein (3 IVUS and 26 fluoroscopy). The 3 filter insertion techniques were compared for “optimal” IVC placement defined as the filter positioning between L1 and L4 vertebrae with tilt <15° based on postprocedure abdominal x-rays or venography. Results: Filter malposition occurred with 6% (6 of 97) bedside IVUS-guided procedures with no malpositions during fluoroscopic imaging. Malposition was lower with the evolved sheath (4%, 2 of 48) compared with the earlier pullback (8%, 4 of 48) insertion technique ( P = .03). The incidence of the filter malposition during IVUS-guided deployment was highest using left femoral access (4 of 10) compared with right femoral (2 of 84) or internal jugular (0 of 3) vein access ( P < .01). Filter tilt occurred more after IVUS-guided procedure (10 of 97) than fluoroscopic procedure (3 of 98; P = .05) and was most frequent for left femoral access (5 of 10 IVUS and 1 of 16 fluoroscopy; P < .01) and was not related to filter type ( P = .13). Conclusion: Our current bedside IVUS-guided IVC filter technique using a single venous puncture and single sheath positioning has improved the placement accuracy. Left femoral venous access should be avoided to minimize the occurrence of filter malpositioning and tilt.
Long-Term Follow-Up of Intracranial Aneurysms Treated With Endovascular Coiling
Authors: Lindvall Peter , Borota Ljubisa , Birgander Richard , Jonasson Per , Ridderheim Per-Åke
Published: April 2012

Background: Our aim was to evaluate the long-term treatment results in patients with intracranial aneurysms treated with endovascular techniques. Methods: Forty-four patients treated due to intracranial aneurysms between 1996 and 2002 were investigated with a time-of-flight sequence magnetic resonance angiography (TOF MRA). Results: Depending on the assessment, 47% to 51% of the treated aneurysms had a residual neck at the last digital subtraction angiography follow-up. There was filling of the aneurysm base (2%) in only 1 patient, whereas the remaining aneurysms were totally occluded. A TOF MRA performed 6 to 14 (mean 9.68) years after the last procedure showed a stable result in 93.9% of the treated aneurysms. There were no de novo aneurysms and previously untreated aneurysms were unchanged in size. Conclusion: Our long-term follow-up showed a stable result in previously coiled intracranial aneurysms.
Making a Space for Medical Expertise: Medical Knowledge of Sexual Assault and the Construction of Boundaries between Forensic Medicine and the Law in Late Nineteenth-century England
Authors: Crozier Ivan , Rees Gethin
Published: May 2012

This article looks at the boundary work performed by Victorian doctors in order to position themselves as beneficial to the court in helping to determine whether a woman had been raped. These doctors provided tangible physical evidence to support already widely-held beliefs about the nature of the rape victim. Such physical evidence could then be used to support, or undermine, the complainant’s allegation. The article concludes that the reliance upon forensic evidence, the result of such boundary construction, is one of the major factors maintaining the current international “justice gap” in rape cases.
Burn-in and the performance quality measures in continuous heterogeneous populations
Authors: Cha Ji Hwan , Finkelstein Maxim
Published: May 2012

Burn-in is a method used to eliminate initial failures in field use. To burn-in a component or system means to subject it to a period of use prior to the time when it is to actually be used. Under the assumption of decreasing or bathtub-shaped population failure rate functions, various problems of determining optimal burn-in have been intensively studied in the literature. In this paper, we assume that a population is composed of stochastically ordered subpopulations, described by their own performance quality measures and study optimal burn-in, which optimizes overall performance measures. It turns out that this setting can justify burn-in even when it is not necessary in the framework of conventional approaches. For instance, it could be reasonable to perform burn-in even when the failure rate function that describes a heterogeneous population of items increases and this is one of the main and important findings of the current study.
Triple-negative breast cancer: are we making headway at least?
Authors: Arnedos Monica , Bihan Celine , Delaloge Suzette , Andre Fabrice
Published: May 2012

The so-called triple-negative breast cancer, as defined by tumors that lack estrogen receptor, progesterone receptor and human epidermal growth factor receptor 2 (HER2) overexpression, has generated growing interest in recent years despite representing less than 20% of all breast cancers. These tumors constitute an important clinical challenge, as they do not respond to endocrine treatment and other targeted therapies. As a group they harbor an aggressive clinical phenotype with early development of visceral metastases and a poor long-term prognosis. While chemotherapy remains effective in triple-negative disease, research continues to further identify potential new targets based on phenotypical and molecular characteristics of these tumors. In this respect, the presence of a higher expression of different biomarkers including epidermal growth factor receptor, vascular endothelial growth factor receptor, fibroblast growth factor receptor and Akt activation has led to a proliferation of clinical trials assessing the role of inhibitors to these pathways in triple-negative tumors. Moreover, the described overlap between triple-negative and basal-like tumors, and the similarities with tumors arising in the BRCA1 mutation carriers has offered potential therapeutic avenues for patients with these cancers including poly (ADP-ribose) polymerase inhibitors and a focus on a higher sensitivity to alkylating chemotherapy agents. Results from these trials have shown some benefit in small subgroups of patients, even in single-agent therapy, which reflects the heterogeneity of triple-negative breast cancer and highlights the need for a further subclassification of these types of tumors for better prognosis identification and treatment individualization.
Perceived Stigmatization, Ingroup Pride, and Immune and Endocrine Activity
Authors: Ratner Kyle G. , Halim May Ling , Amodio David M.
Published: May 2012

Racial disparities are a major public health concern in the United States. The authors examined whether Black and Latina community members’ perceptions of stigmatization and personal feelings about their group relate to immune and endocrine markers associated with health risk, including the cytokine interleukin-6 (IL-6), which coordinates the immune response to infection, the anabolic hormone dehydroepiandrosterone (DHEA), which promotes cellular resilience, and the catabolic hormone cortisol, which releases metabolic stores in response to threat. Greater perceived stigmatization was associated with higher basal IL-6, whereas greater ingroup pride was related to elevated basal DHEA. These associations remained with adjustment for general perceived stress, experience with discrimination, age, and income. No significant perceived stigmatization or ingroup pride effects emerged for basal cortisol. These findings provide new evidence that perceived stigmatization and ingroup pride are linked to indicators of disease and resilience, respectively, highlighting mechanisms through which racial and ethnic stigmatization may contribute to health disparities.
Infusion of hemolyzed red blood cells within peripheral blood stem cell grafts in patients with and without sickle cell disease
Authors: Fitzhugh Courtney D. , Unno Hayato , Hathaway Vincent , Coles Wynona A. , Link Mary E. , Weitzel R. Patrick , Zhao Xiongce , Wright Elizabeth C. , Stroncek David F. , Kato Gregory J. , Hsieh Matthew M. , Tisdale John F.
Published: May 2012

Peripheral blood stem cell (PBSC) infusions are associated with complications such as elevated blood pressure and decreased creatinine clearance. Patients with sickle cell disease experience similar manifestations, and some have postulated release of plasma-free hemoglobin with subsequent nitric oxide consumption as causative. We sought to evaluate whether the infusion of PBSC grafts containing lysed red blood cells (RBCs) leads to the toxicity observed in transplant subjects. We report a prospective cohort study of 60 subjects divided into 4 groups based on whether their infusions contained dimethyl sulfoxide (DMSO) and lysed RBCs, no DMSO and fresh RBCs, DMSO and no RBCs, or saline. Our primary end point, change in maximum blood pressure compared with baseline, was not significantly different among groups. Tricuspid regurgitant velocity and creatinine levels also did not differ significantly among groups. Our data do not support free hemoglobin as a significant contributor to toxicity associated with PBSC infusions. This study was registered at clinicaltrials.gov (NCT00631787).
IKKα-mediated signaling circuitry regulates early B lymphopoiesis during hematopoiesis
Authors: Balkhi Mumtaz Yaseen , Willette-Brown Jami , Zhu Feng , Chen Zhisong , Liu Shuang , Guttridge Denis C. , Karin Michael , Hu Yinling
Published: April 2012

Multiple transcription factors regulate B-cell commitment, which is coordinated with myeloid-erythroid lineage differentiation. NF-κB has long been speculated to regulate early B-cell development; however, this issue remains controversial. IκB kinase-α (IKKα) is required for splenic B-cell maturation but not for BM B-cell development. In the present study, we unexpectedly found defective BM B-cell development and increased myeloid-erythroid lineages in kinase-dead IKKα (KA/KA) knock-in mice. Markedly increased cytosolic p100, an NF-κB2–inhibitory form, and reduced nuclear NF-κB p65, RelB, p50, and p52, and IKKα were observed in KA/KA splenic and BM B cells. Several B- and myeloid-erythroid–cell regulators, including Pax5, were deregulated in KA/KA BM B cells. Using fetal liver and BM congenic transplantations and deleting IKKα from early hematopoietic cells in mice, this defect was identified as being B cell–intrinsic and an early event during hematopoiesis. Reintroducing IKKα, Pax5, or combined NF-κB molecules promoted B-cell development but repressed myeloid-erythroid cell differentiation in KA/KA BM B cells. The results of the present study demonstrate that IKKα regulates B-lineage commitment via combined canonical and noncanonical NF-κB transcriptional activities to target Pax5 expression during hematopoiesis.
Predicting the outer membrane proteome of Pasteurella multocida based on consensus prediction enhanced by results integration and manual confirmation
Authors: E-komon Teerasak , Burchmore Richard , Herzyk Pawel , Davies Robert
Published: April 2012

Background

Outer membrane proteins (OMPs) of Pasteurella multocida have various functions related to virulence and pathogenesis and represent important targets for vaccine development. Various bioinformatic algorithms can predict outer membrane localization and discriminate OMPs by structure or function. The designation of a confident prediction framework by integrating different predictors followed by consensus prediction, results integration and manual confirmation will improve the prediction of the outer membrane proteome.

Results

In the present study, we used 10 different predictors classified into three groups (subcellular localization, transmembrane β-barrel protein and lipoprotein predictors) to identify putative OMPs from two available P. multocida genomes: those of avian strain Pm70 and porcine non-toxigenic strain 3480. Predicted proteins in each group were filtered by optimized criteria for consensus prediction: at least two positive predictions for the subcellular localization predictors, three for the transmembrane β-barrel protein predictors and one for the lipoprotein predictors. The consensus predicted proteins were integrated from each group into a single list of proteins. We further incorporated a manual confirmation step including a public database search against PubMed and sequence analyses, e.g. sequence and structural homology, conserved motifs/domains, functional prediction, and protein-protein interactions to enhance the confidence of prediction. As a result, we were able to confidently predict 98 putative OMPs from the avian strain genome and 107 OMPs from the porcine strain genome with 83% overlap between the two genomes.

Conclusions

The bioinformatic framework developed in this study has increased the number of putative OMPs identified in P. multocida and allowed these OMPs to be identified with a higher degree of confidence. Our approach can be applied to investigate the outer membrane proteomes of other Gram-negative bacteria.
Fitting hidden Markov models of protein domains to a target species: application to Plasmodium falciparum
Authors: Terrapon Nicolas , Gascuel Olivier , Maréchal Éric , Bréhélin Laurent
Published: May 2012

Background

Hidden Markov Models (HMMs) are a powerful tool for protein domain identification. The Pfam database notably provides a large collection of HMMs which are widely used for the annotation of proteins in new sequenced organisms. In Pfam, each domain family is represented by a curated multiple sequence alignment from which a profile HMM is built. In spite of their high specificity, HMMs may lack sensitivity when searching for domains in divergent organisms. This is particularly the case for species with a biased amino-acid composition, such asP. falciparum, the main causal agent of human malaria. In this context, fitting HMMs to the specificities of the target proteome can help identify additional domains.

Results

UsingP. falciparumas an example, we compare approaches that have been proposed for this problem, and present two alternative methods. Because previous attempts strongly rely on known domain occurrences in the target species or its close relatives, they mainly improve the detection of domains which belong to already identified families. Our methods learn global correction rules that adjust amino-acid distributions associated with the match states of HMMs. These rules are applied to all match states of the whole HMM library, thus enabling the detection of domains from previously absent families. Additionally, we propose a procedure to estimate the proportion of false positives among the newly discovered domains. Starting with the Pfam standard library, we build several new libraries with the different HMM-fitting approaches. These libraries are first used to detect new domain occurrences with low E-values. Second, by applying the Co-Occurrence Domain Discovery (CODD) procedure we have recently proposed, the libraries are further used to identify likely occurrences among potential domains with higher E-values.

Conclusion

We show that the new approaches allow identification of several domain families previously absent in theP. falciparumproteome and the Apicomplexa phylum, and identify many domains that are not detected by previous approaches. In terms of the number of new discovered domains, the new approaches outperform the previous ones when no close species are available or when they are used to identify likely occurrences among potential domains with high E-values. All predictions onP. falciparumhave been integrated into a dedicated website which pools all known/new annotations of protein domains and functions for this organism. A software implementing the two proposed approaches is available at the same address:http://www.lirmm.fr/~terrapon/HMMfit/
Accelerated maximum likelihood parameter estimation for stochastic biochemical systems
Authors: Daigle Bernie J , Roh Min K , Petzold Linda R , Niemi Jarad
Published: May 2012

Background

A prerequisite for the mechanistic simulation of a biochemical system is detailed knowledge of its kinetic parameters. Despite recent experimental advances, the estimation of unknown parameter values from observed data is still a bottleneck for obtaining accurate simulation results. Many methods exist for parameter estimation in deterministic biochemical systems; methods for discrete stochastic systems are less well developed. Given the probabilistic nature of stochastic biochemical models, a natural approach is to choose parameter values that maximize the probability of the observed data with respect to the unknown parameters, a.k.a. the maximum likelihood parameter estimates (MLEs). MLE computation for all but the simplest models requires the simulation of many system trajectories that are consistent with experimental data. For models with unknown parameters, this presents a computational challenge, as the generation of consistent trajectories can be an extremely rare occurrence.

Results

We have developed Monte Carlo Expectation-Maximization with Modified Cross-Entropy Method (MCEM2): an accelerated method for calculating MLEs that combines advances in rare event simulation with a computationally efficient version of the Monte Carlo expectation-maximization (MCEM) algorithm. Our method requires no prior knowledge regarding parameter values, and it automatically provides a multivariate parameter uncertainty estimate. We applied the method to five stochastic systems of increasing complexity, progressing from an analytically tractable pure-birth model to a computationally demanding model of yeast-polarization. Our results demonstrate that MCEM2substantially accelerates MLE computation on all tested models when compared to a stand-alone version of MCEM. Additionally, we show how our method identifies parameter values for certain classes of models more accurately than two recently proposed computationally efficient methods.

Conclusions

This work provides a novel, accelerated version of a likelihood-based parameter estimation method that can be readily applied to stochastic biochemical systems. In addition, our results suggest opportunities for added efficiency improvements that will further enhance our ability to mechanistically simulate biological processes.
Remobilization of Tol2 transposons in Xenopus tropicalis
Authors: Yergeau Donald A , Kelley Clair M , Kuliyev Emin , Zhu Haiqing , Sater Amy K , Wells Dan E , Mead Paul E
Published: May 2012

Background

The Class II DNA transposons are mobile genetic elements that move DNA sequence from one position in the genome to another. We have previously demonstrated that the naturally occurring Tol2 element from Oryzias latipes efficiently integrates its corresponding non-autonomous transposable element into the genome of the diploid frog, Xenopus tropicalis. Tol2 transposons are stable in the frog genome and are transmitted to the offspring at the expected Mendelian frequency.

Results

To test whether Tol2 transposons integrated in the Xenopus tropicalis genome are substrates for remobilization, we injected in vitro transcribed Tol2 mRNA into one-cell embryos harbouring a single copy of a Tol2 transposon. Integration site analysis of injected embryos from two founder lines showed at least one somatic remobilization event per embryo. We also demonstrate that the remobilized transposons are transmitted through the germline and re-integration can result in the generation of novel GFP expression patterns in the developing tadpole. Although the parental line contained a single Tol2 transposon, the resulting remobilized tadpoles frequently inherit multiple copies of the transposon. This is likely to be due to the Tol2 transposase acting in discrete blastomeres of the developing injected embryo during the cell cycle after DNA synthesis but prior to mitosis.

Conclusions

In this study, we demonstrate that single copy Tol2 transposons integrated into the Xenopus tropicalis genome are effective substrates for excision and random re-integration and that the remobilized transposons are transmitted through the germline. This is an important step in the development of 'transposon hopping' strategies for insertional mutagenesis, gene trap and enhancer trap screens in this highly tractable developmental model organism.
Knockout of the folate transporter folt-1 causes germline and somatic defects in C. elegans
Authors: Austin Misa U , Liau Wei-Siang , Balamurugan Krishnaswamy , Ashokkumar Balasubramaniem , Said Hamid M , LaMunyon Craig W
Published: May 2012

Background

The C. elegans gene folt-1 is an ortholog of the human reduced folate carrier gene. The FOLT-1 protein has been shown to transport folate and to be involved in uptake of exogenous folate by worms. A knockout mutation of the gene, folt-1(ok1460), was shown to cause sterility, and here we investigate the source of the sterility and the effect of the folt-1 knockout on somatic function.

Results

Our results show that folt-1(ok1460) knockout hermaphrodites have a substantially reduced germline, generate a small number of functional sperm, and only rarely produce a functional oocyte. We found no evidence of increased apoptosis in the germline of folt-1 knockout mutants, suggesting that germline proliferation is defective. While folt-1 knockout males are fertile, their rate of spermatogenesis was severely diminished, and the males were very poor maters. The mating defect is likely due to compromised metabolism and/or other somatic functions, as folt-1 knockout hermaphrodites displayed a shortened lifespan and elongated defecation intervals.

Conclusions

The FOLT-1 protein function affects both the soma and the germline. folt-1(ok1460) hermaphrodites suffer severely diminished lifespan and germline defects that result in sterility. Germline defects associated with folate deficiency appear widespread in animals, being found in humans, mice, fruit flies, and here, nematodes.
Comprehensive survey of human brain microRNA by deep sequencing
Authors: Shao Ning-Yi , Hu Hai Yang , Yan Zheng , Xu Ying , Hu Hao , Menzel Corinna , Li Na , Chen Wei , Khaitovich Philipp
Published: May 2012

Background

MicroRNA (miRNA) play an important role in gene expression regulation. At present, the number of annotated miRNA continues to grow rapidly, in part due to advances of high-throughput sequencing techniques. Here, we use deep sequencing to characterize a population of small RNA expressed in human and rhesus macaques brain cortex.

Results

Based on a total of more than 150 million sequence reads we identify 197 putative novel miRNA, in humans and rhesus macaques, that are highly conserved among mammals. These putative miRNA have significant excess of conserved target sites in genes' 3'UTRs, supporting their functional role in gene regulation. Additionally, in humans and rhesus macaques respectively, we identify 41 and 22 conserved putative miRNA originating from non-coding RNA (ncRNA) transcripts. While some of these molecules might function as conventional miRNA, others might be harmful and result in target avoidance.

Conclusions

Here, we further extend the repertoire of conserved human and rhesus macaque miRNA. Even though our study is based on a single tissue, the coverage depth of our study allows identification of functional miRNA present in brain tissue at background expression levels. Therefore, our study might cover large proportion of the yet unannotated conserved miRNA present in the human genome.
Clonal complexes and virulence factors of Staphylococcus aureus from several cities in India
Authors: Shambat Srikanth , Nadig Savitha , Prabhakara Sushma , Bes Michele , Etienne Jerome , Arakere Gayathri
Published: May 2012

Background

Diseases fromStaphylococcus aureusare a major problem in Indian hospitals and recent studies point to infiltration of community associated methicillin resistantS. aureus(CA-MRSA) into hospitals. Although CA-MRSA are genetically different from nosocomial MRSA, the distinction between the two groups is blurring as CA-MRSA are showing multidrug resistance and are endemic in many hospitals. Our survey of samples collected from Indian hospitals between 2004 and 2006 had shown mainly hospital associated methicillin resistantStaphylococcus aureus(HA-MRSA) carrying staphylococcal cassette chromosomemec(SCCmec) type III and IIIA. ButS. aureusisolates collected from 2007 onwards from community and hospital settings in India have shown SCCmectype IV and V cassettes while several variations of type IV SCCmeccassettes from IVa to IVj have been found in other parts of the world. In the present study, we have collected nasal swabs from rural and urban healthy carriers and pus, blood etc from in patients from hospitals to study the distribution of SCCmecelements and sequence types (STs) in the community and hospital environment. We performed molecular characterization of all the isolates to determine their lineage and microarray of select isolates from each sequence type to analyze their toxins, virulence and immune-evasion factors.

Results

Molecular analyses of 68 S. aureusisolates from in and around Bengaluru and three other Indian cities have been carried out. The chosen isolates fall into fifteen STs with all major clonal complexes (CC) present along with some minor ones. The dominant MRSA clones are ST22 and ST772 among healthy carriers and patients. We are reporting three novel clones, two methicillin sensitiveS. aureus(MSSA) isolates belonging to ST291 (related to ST398 which is live stock associated), and two MRSA clones, ST1208 (CC8), and ST672 as emerging clones in this study for the first time. Sixty nine percent of isolates carry Panton- Valentine Leucocidin genes (PVL) along with many other toxins. There is more diversity of STs among methicillin sensitiveS. aureusthan resistant ones. Microarray analysis of isolates belonging to different STs gives an insight into major toxins, virulence factors, adhesion and immune evasion factors present among the isolates in various parts of India.

Conclusions

S. aureusisolates reported in this study belong to a highly diverse group of STs and CC and we are reporting several new STs which have not been reported earlier along with factors influencing virulence and host pathogen interactions.
The mechanism of pollination drop withdrawal in Ginkgo biloba L.
Authors: Jin Biao , Zhang Lei , Lu Yan , Wang Di , Jiang Xiao X , Zhang Min , Wang Li
Published: May 2012

Background

The pollination drop (PD) is a characteristic feature of many wind-pollinated gymnosperms. Although accumulating evidence shows that the PD plays a critical role in the pollination process, the mechanism of PD withdrawal is still unclear. Here, we carefully observed the PD withdrawal process and investigated the underlying mechanism of PD withdrawal, which will aid the understanding of wind-pollination efficiency in gymnosperms.

Results

In Ginkgo biloba, PDs were secreted on the micropyle during the pollination period and persisted for about 240 h when not pollinated under laboratory conditions. The withdrawal of an isolated PD required only 1 h for evaporation, much less than a PD on the living ovule, which required 100 h. When pollinated with viable pollen, PDs withdrew rapidly within 4 h. In contrast, nonviable pollen and acetone-treated pollen did not cause PD withdrawal. Although 100% relative humidity significantly inhibited PD withdrawal, pollinated PDs still could withdraw completely within 48 h. Pollen grains of Cycas revoluta, which are similar to those of G. biloba, could induce PD withdrawal more rapidly than those of two distantly related gymnosperms (Pinus thunbergii and Abies firma) or two angiosperms (Paeonia suffruticosa and Orychophragmus violaceus). Furthermore, pollen of G. biloba and C. revoluta submerged immediately when encountering the PD, then sank to the bottom and entered the micropyle. The saccate pollen of P. thunbergii and A. firma submerged into the PD, but remained floating at the top and finally accumulated on the micropyle after PD withdrawal. In contrast, pollen of the angiosperms P. suffruticosa, Salix babylonica, and O. violaceus did not submerge, instead remaining clustered at the edge without entering the PD.

Conclusions

We conclude that PD withdrawal is primarily determined by the dynamic balance between evaporation and ovule secretion, of which pollen is a critical stimulator. When conspecific pollen grains were submerged in the PD, ovule secretion was subsequently terminated and active absorption occurred. These processes cooperated to influence PD withdrawal. In addition, pollen grain behavior within PDs varied dramatically among taxa, and PDs played a role in distinguishing and transporting pollen in G. biloba.
Microwave absorption properties of Ni/(C, silicides) nanocapsules
Authors: Jiang Jingjing , Wang Han , Guo Huaihong , Yang Teng , Tang Wen-Shu , Li Da , Ma Song , Geng Dianyu , Liu Wei , Zhang Zhidong
Published: May 2012

The microwave absorption properties of Ni/(C, silicides) nanocapsules prepared by an arc discharge method have been studied. The composition and the microstructure of the Ni/(C, silicides) nanocapsules were determined by means of X-ray diffraction, X-ray photoelectric spectroscopy, and transmission electron microscope observations. Silicides, in the forms of SiOx and SiC, mainly exist in the shells of the nanocapsules and result in a large amount of defects at the ‘core/shell’ interfaces as well as in the shells. The complex permittivity and microwave absorption properties of the Ni/(C, silicides) nanocapsules are improved by the doped silicides. Compared with those of Ni/C nanocapsules, the positions of maximum absorption peaks of the Ni/(C, silicides) nanocapsules exhibit large red shifts. An electric dipole model is proposed to explain this red shift phenomenon.
UK Dermatology Clinical Trials Network’s STOP GAP trial (a multicentre trial of prednisolone versus ciclosporin for pyoderma gangrenosum): protocol for a randomised controlled trial
Authors: Craig Fiona F , Thomas Kim S , Mitchell Eleanor J , Williams Hywel C , Norrie John , Mason James M , Ormerod Anthony D
Published: April 2012

Background

Pyoderma gangrenosum (PG) is a rare inflammatory skin disorder characterised by painful and rapidly progressing skin ulceration. PG can be extremely difficult to treat and patients often require systemic immunosuppression. Recurrent lesions of PG are common, but the relative rarity of this condition means that there is a lack of published evidence regarding its treatment. A systematic review published in 2005 found no randomised controlled trials (RCTs) relating to the treatment of PG. Since this time, one small RCT has been published comparing infliximab to placebo, but none of the commonly used systemic treatments for PG have been formally assessed. The UK Dermatology Clinical Trials Network’s STOP GAP Trial has been designed to address this lack of trial evidence.

Methods

The objective is to assess whether oral ciclosporin is more effective than oral prednisolone for the treatment of PG. The trial design is a two-arm, observer-blind, parallel-group, randomised controlled trial comparing ciclosporin (4 mg/kg/day) to prednisolone (0.75 mg/kg/day). A total of 140 participants are to be recruited over a period of 4 years, from up to 50 hospitals in the UK and Eire. Primary outcome of velocity of healing at 6 weeks is assessed blinded to treatment allocation (using digital images of the ulcers). Secondary outcomes include: (i) time to healing; (ii) global assessment of improvement; (iii) PG inflammation assessment scale score; (iv) self-reported pain; (v) health-related quality of life; (vi) time to recurrence; (vii) treatment failures; (viii) adverse reactions to study medications; and (ix) cost effectiveness/utility. Patients with a clinical diagnosis of PG (excluding granulomatous PG); measurable ulceration (that is, not pustular PG); and patients aged over 18 years old who are able to give informed consent are included in the trial. Randomisation is by computer generated code using permuted blocks of randomly varying size, stratified by lesion size, and presence or absence of underlying systemic disease (for example, rheumatoid arthritis).

Patients who require topical therapy are asked to enter a parallel observational study (case series). If topical therapy fails and systemic therapy is required, participants are then considered for inclusion in the randomised trial.

Trial registration

Current controlled trials: ISRCTN35898459. Eudract No.2008-008291-14.
The nature of personality disorder
Authors: Adshead Gwen , Sarkar Jaydip
Published: May 2012

The lack of a medically grounded approach to personality disorder and its management has led to its comparative neglect as a topic by many clinicians in the UK. In this article we present evidence that personality disorders are, like other mental disorders, the social manifestations of a pathological process. This process presents with characteristic clinical features that are developmental in nature. These cause disturbances in arousal, affect and reality testing that have an impact on interpersonal social functioning. Personality disorder may therefore be conceived of primarily as a socioemotional disability, not dissimilar to Axis I conditions.
Psychiatric and psychological aspects of fraud offending
Authors: Wallang Paul , Taylor Richard
Published: May 2012

There has been little research into the interaction between fraud offences and mental health. Fraud is perpetrated on a massive scale and a number of offenders will have psychiatric pathology either as a primary driver of the offence or as an associated phenomenon that will require psychiatric care and treatment. This article reviews the broad range of psychiatric conditions that have been associated with fraud offending, comments on management and discusses methods of psychiatric assessment in fraud offences.
From the gambler within: Dostoyevsky's The Gambler
Authors: George Sanju
Published: May 2012

Fyodor Dostoyevsky is widely regarded as the greatest 19th-century Russian writer and a giant in world literature. He is familiar to literary-inclined psychiatrists for his rich and accurate portrayal of mental illness in several of his works. But his own chronic addiction to gambling and its consequent perils are less well-known. This article discusses The Gambler, one of Dostoyevsky's early (1866) semi-autobiographical novellas, inspired by his own addiction to roulette, focusing on its depiction of gambling. To better understand Dostoyevsky the gambler, the article also presents brief excerpts from letters that he wrote to his wife in 1867, when his gambling addiction appears to have been at its worst. Finally, the relevance of the central theme of this work, gambling addiction, to the present-day psychiatrist is discussed.
A reflection on continuing professional development
Authors: O'Loughlin Kieran , Guerandel Allys , Malone Kevin
Published: May 2012

The enactment of Part II of the Medical Practitioners Act 2007 in Ireland heralds a move from voluntary to statutory provision of professional competence and marks an important advance in medical professionalism in the country. This formalises consultant psychiatrists' existing commitment to updating their knowledge and skills and compels basic and higher specialist trainees to actively engage in the process. The relevance of reflective practice for professional and personal development of trainee psychiatrists is discussed and the role of existing trainee learning activities in the process of lifelong learning is explored in this context.
Long-Term Analysis of the IFM 99 Trials for Myeloma: Cytogenetic Abnormalities [t(4;14), del(17p), 1q gains] Play a Major Role in Defining Long-Term Survival
Authors: Avet-Loiseau Hervé , Attal Michel , Campion Loic , Caillot Denis , Hulin Cyrille , Marit Gerald , Stoppa Anne-Marie , Voillat Laurent , Wetterwald Marc , Pegourie Brigitte , Voog Eric , Tiab Mourad , Banos Anne , Jaubert Jerome , Bouscary Didier , Macro Margaret , Kolb Brigitte , Traulle Catherine , Mathiot Claire , Magrangeas Florence , Minvielle Stephane , Facon Thierry , Moreau Philippe
Published: May 2012

Purpose

In multiple myeloma, many prognostic parameters have been proposed. However, all of these predict shorter survival. To identify patients with a longer life expectancy, we updated the data of patients treated in the IFM (Intergroupe Francophone du Myelome) 99-02 and 99-04 trials.

Patients and Methods

A series of 520 patients was analyzed. Median follow-up was 90.5 months. To perform a comprehensive analysis of the major prognostic factors, we reanalyzed all patients for 1q gains [in addition to updating del(13), t(4;14), and del(17p) analyses].

Results

It was possible to identify a subgroup of patients (representing 20% of total patients) with an 8-year survival of 75%. These patients were defined by the absence of t(4;14), del(17p), and 1q gain and β2-microglobulin less than 5.5 mg/L.

Conclusion

We propose that all patients with newly diagnosed multiple myeloma be evaluated for these three chromosomal changes, not only to define high-risk patients but also to identify those with a longer life expectancy.
Panobinostat in Patients With Relapsed/Refractory Hodgkin's Lymphoma After Autologous Stem-Cell Transplantation: Results of a Phase II Study
Authors: Younes Anas , Sureda Anna , Ben-Yehuda Dina , Zinzani Pier Luigi , Ong Tee-Chuan , Prince H. Miles , Harrison Simon J. , Kirschbaum Mark , Johnston Patrick , Gallagher Jennifer , Le Corre Christophe , Shen Angela , Engert Andreas
Published: May 2012

Purpose

Hodgkin's lymphoma (HL) has no standard of care for patients who are relapsed or refractory to autologous stem-cell transplantation (ASCT). This phase II study examined safety and activity of panobinostat in this population.

Patients and Methods

Panobinostat 40 mg was administered orally three times per week. The primary end point was objective response rate (ORR) based on investigator assessment of radiologic imaging. Secondary end points included ORR by independent central review, time to response (TTR), duration of response (DOR), progression-free survival (PFS), overall survival, and safety. Exploratory biomarker analyses were performed.

Results

The 129 treated patients (median age, 32 years; range, 18 to 75 years) were heavily pretreated with a median of four (range, two to seven) prior systemic regimens, and 41% did not respond to the regimen immediately preceding panobinostat. Tumor reductions occurred in 96 patients (74%). Objective response was achieved by 35 patients (27%), including 30 (23%) partial responses and five (4%) complete responses. The median TTR was 2.3 months, median DOR was 6.9 months, and median PFS was 6.1 months. The estimated 1-year overall survival rate was 78%. Common nonhematologic adverse events (AEs)—diarrhea, nausea, vomiting, and fatigue—were generally grade 1 and 2. Most common grade 3 and 4 hematologic AEs—thrombocytopenia, anemia, and neutropenia—were manageable. Early reductions in thymus and activation-regulated chemokine were observed in patients achieving complete or partial response.

Conclusion

In the largest, prospective, multicenter, international trial conducted in heavily pretreated patients with HL who relapsed or were refractory to ASCT, panobinostat monotherapy demonstrated antitumor activity, resulting in durable responses.
The effect of settling velocity on the transport of mussel larvae in a cobble‐bed river: Water column and near‐bed turbulence
Authors: Schwalb Astrid Nadine , Morris Todd James , Ackerman Josef Daniel
Published: May 2012

Lay Abstract

Simple transport models predict that the distance small organisms such as larvae “drift” downstream in rivers is determined by their settling velocity, the release height, and the stream velocity. However, natural turbulent conditions in a river may also affect the downstream transport and dispersion (spread) of larvae. The main goal of this study was to examine how stream velocity and larval settling velocity (Mucket [Actinonaias ligamentina] and the Wavy‐rayed Lampmussel [Lampsilis fasciola] differ by 2.5 times) affect the transport of freshwater unionid mussel larvae in the Grand River, Ontario, Canada. Larvae were released and captured in a series of nets downstream. Larval spread in rivers appeared to be strongly affected by stream flow conditions. Larvae were spread more rapidly with increased stream velocity likely due to increased turbulence in the water. Overall there was a good agreement between measured downstream decrease in capture of larvae and predictions from a 3‐dimensional advection–diffusion model that considered the spread due to hydrodynamics. However, in contrast to the predictions of simple transport models, differences in settling velocity had no detectable effect on the transport of larvae. Future studies are necessary to further explore the role of settling velocity and other factors under different stream flow conditions, which may also be important for dispersal of other organisms and particles.