bluuebunny/crossref_metadata_2025 huggingface dataset:
Centromeric chromatin and its dynamics in plants
Authors: Lermontova Inna , Sandmann Michael , Mascher Martin , Schmit Anne‐Catherine , Chabouté Marie‐Edith
Published: May 2015

Centromeres are chromatin structures that are required for proper separation of chromosomes during mitosis and meiosis. The centromere is composed of centromeric DNA, often enriched in satellite repeats, and kinetochore complex proteins. To date, over 100 kinetochore components have been identified in various eukaryotes. Kinetochore assembly begins with incorporation of centromeric histone H3 variant CENH3 into centromeric nucleosomes. Protein components of the kinetochore are either present at centromeres throughout the cell cycle or localize to centromeres transiently, prior to attachment of microtubules to each kinetochore in prometaphase of mitotic cells. This is the case for the spindle assembly checkpoint (SAC) proteins in animal cells. The SAC complex ensures equal separation of chromosomes between daughter nuclei by preventing anaphase onset before metaphase is complete, i.e. the sister kinetochores of all chromosomes are attached to spindle fibers from opposite poles. In this review, we focus on the organization of centromeric DNA and the kinetochore assembly in plants. We summarize recent advances regarding loading of CENH3 into the centromere, and the subcellular localization and protein–protein interactions of Arabidopsis thaliana proteins involved in kinetochore assembly and function. We describe the transcriptional activity of corresponding genes based on in silico analysis of their promoters and cell cycle‐dependent expression. Additionally, barley homologs of all selected A. thaliana proteins have been identified in silico, and their sequences and domain structures are presented.
Preoperative anaemia and newly diagnosed cancer 1 year after elective total hip and knee arthroplasty
Authors: Jørgensen C. C. , Jans Ø. , Kehlet H. ,   the Lundbeck Foundation Centre for Fast‐track Hip and Knee Replacement Collaborative Group
Published: May 2015

Background

Preoperative anaemia is a well‐established risk factor for use of blood transfusions and postoperative morbidity. Consequently, focus on preoperative evaluation of haemoglobin levels is increasing. In this context, iron deficiency anaemia may be a symptom of undiscovered gastrointestinal (GI) cancer requiring further investigation. However, the association between preoperative anaemia and cancer 1 year after elective total hip (THA) and total knee arthroplasty (TKA) is unknown. We evaluated 1‐year cancer diagnoses, particularly GI cancers, in anaemic and non‐anaemic THA and TKA patients.

Study Design and Methods

A prospective database on preoperative patient characteristics from six Danish orthopaedic centres was cross‐referenced with the Danish Cancer Registry for information on diagnoses of new cancers 1 year after surgery. Crude cancer risk estimates were calculated using chi‐square and Fisher's exact test in the total study cohort. Adjusted risk estimates were obtained using propensity scores and the Mantel–Haenzel statistic.

Results

Of 5400 procedures, 731 (13·5%) were in anaemic patients. These were older and had more comorbidity than non‐anaemic patients. There were 17 (2·3%) and 79 (1·6%) new cancers in anaemic and non‐anaemic patients, respectively (OR: 1·38; 95% CI: 0·81–2·35, P = 0·228). After propensity matching of 661 anaemic and 1305 non‐anaemic patients, we found no association between preoperative anaemia and cancer (OR: 0·94; 95% CI: 0·51–1·73, P = 0·837) or with GI cancers specifically (OR: 0·80; 95% CI: 0·25‐2·56, P = 0·707).

Conclusion

Preoperative anaemia per se may not be related to being diagnosed with cancer 1 year after THA and TKA. The optimal criteria for preoperative referral of anaemic patients to gastroenterologist in elective THA and TKA need further investigation.
The grammatical features of English in a Chinese Internet discussion forum
Authors: AI HAIYANG , YOU XIAOYE
Published: May 2015

Recent research in world Englishes shows that the lexis‐grammar interface, or lexicogrammar, constitutes an important area for investigating structural nativisation of local varieties of English (Schilk). While most studies of lexicogrammar have focused on Inner Circle and Outer Circle varieties, the study presented in this paper focuses on an Expanding Circle variety, China English, and explores some of its patterns of structural nativisation. Utilising large‐scale corpus data collected from an online discussion forum, this study examines several locally emergent linguistic patterns in China English, including new ditransitive verbs, verb‐complementation, and collocation. The results suggest that there exist certain associations between specific lexical items and grammatical constructions in this local variety.
Analysing China's English‐language media
Authors: ALVARO JOSEPH JAMES
Published: May 2015

This paper is a sociolinguistic view of China's English language media and its attempted penetration of the global language community. Using Kachru's Caliban dynamic as a metaphor, I examine how China attempts to send an ideologically loaded, Sinocentric English back to the ‘colonisers’. The careful construction of language (linguistic engineering) for political purposes is discussed in its various forms of officialese and fixed formulations as peculiar to the Chinese political tradition. The paper concludes by suggesting that due to its limited interest to global society in general, and other reasons, the language of China's politicised English outreach (i.e. Zhonglish, Xinhua English, New China Newspeak) will continue to retain only a marginal global media presence until ideological divides can be bridged.
Elementary School Students’ Self-Determination in Physical Education and Attitudes Toward Physical Activity
Authors: Chen Weiyun , Hypnar Andrew J.
Published: May 2015

Motivations for and positive attitudes toward physical activity (PA) developed during childhood are likely to be carried over to adulthood. The purpose of this study was to examine the relationship between three psychological needs satisfaction, motivational regulations in physical education (PE), and attitudes toward participation in leisure-time PA among upper elementary school students. One thousand and seventy-three students in grades 3-5 anonymously and voluntarily completed three measures, including Psychological Needs Satisfaction, Motivational Regulations, and Attitudes, which were modified from previous works and judged by a panel of experts to ensure the wording of each item was understandable for upper elementary school students. The data were analyzed with descriptive statistics, composite reliability coefficient, and multilevel confirmatory factor analysis methods. The results indicated that the composite reliability coefficients of the measures were above .60, ranging from .62 to .79. The results of structural equation model indicated that satisfactions of autonomy, competence, and relatedness were significantly instrumental to the enhancement of autonomous motivation in PE settings and attitudes toward PA participation. Elementary school students’ having fun, obtaining benefits, and being with friends were all major motivational factors contributing to positive attitudes toward PA outside of school.
Novice Physical Education Teachers Learning to Teach
Authors: Banville Dominique
Published: May 2015

Support, or lack thereof, is often cited as the main reason for teachers to leave the profession early on (Ingersoll, 2003). Feiman-Nemser (2001) identifies five Central Tasks associated with Learning to Teach (CTLT) that could focus the support novice teachers need during their induction years: learning the teaching context (TC), designing responsive instructional program (IP), creating a classroom learning community (CC), enacting a beginning repertoire (BR) and developing their professional identity (PI). The purpose of the study is to examine the CTLT that novice physical education teachers use in their first and second years of their teaching career. Twenty-one physical education teachers accepted the study parameters to be observed and interviewed during their first year of teaching, and 15 teachers continued the data collection into their second year. Interviews revealed that these teachers focused mainly on BR and TC. Little focus was given to IP, CC, and PI. Results indicate the need for effective mentoring and continuous support through their induction years on BR and TC, but also expand novice teachers’ focus to address the additional categories.
Success as a Springboard for Novice Physical Education Teachers in Their Efforts to Develop a Professional Career
Authors: Zach Sima , Stein Hanan , Sivan Tamar , Harari Israel , Nabel-Heller Noa
Published: May 2015

This article explored how 45 novice physical education teachers perceived success, and how success affected their motivation to continue teaching. Self-determination theory (SDT) was used to interpret the teachers’ written reports, and focus group discussions were held concerning their success. Satisfaction with the competence, relatedness, and autonomy of the teachers’ needs were related to the teachers’ perception of success. Based on the findings, we contend that SDT can have strong implications for both school life and professional development facilitators. We suggest that strengthening certain aspects of success from the very beginning of the teaching experience may lead to a better adjustment to teaching.
“Whatever Is Comfortable:” Secondary Physical Educators’ Curricular Decision Making: Issues of Knowledge and Gendered Performativity
Authors: Ferry Matthew , McCaughtry Nate
Published: May 2015

Throughout history there have been debates as to what content knowledge (CK) is of most value for physical education (PE). Much recent conversation has circulated around the hope that time spent in PE supports students’ regular participation in physical activity (PA). Researchers’ use of the term PA, however, often stresses the similarities while ignoring important differences. Utilizing teacher knowledge theory, feminist poststructural scholarship, and interpretive methodologies we attempted to better understand how teachers selected curricular content by examining their CK. We found that the teachers’ PA biographies led them to develop deeply embodied and gendered knowledge and competencies, or ±comfort,“ when it came to teaching particular PAs, and this was a major factor in how they selected curricular content. Implications of the study highlight the socially constructed nature of teacher CK and issues associated with secondary PE curricula and wider physical activity culture(s).
Critical Pedagogies in PETE: An Antipodean Perspective
Authors: Philpot Rod
Published: May 2015

In the 1990s, New Zealand and Australia rolled out new school physical education curriculums (Ministry of Education, 1999, 2007; Queensland School Curriculum Council, 1999) signaling a significant change in the purpose of physical education in both countries. These uniquely Antipodean1 curriculum documents were underpinned by a socially critical perspective and physical education teacher education (PETE) programs in both countries needed to adapt to prepare teachers who are capable of engaging PE from a socially critical perspective. One way they attempted to do this was to adopt what has variously been labeled critical pedagogy. Critical pedagogies as a label is something of ‘big tent’ (Lather, 1998) and this paper reports on the published attempts to operationalize critical pedagogy and its reported success or otherwise in preparing teachers for the expectations of the socially critical oriented HPE curriculum in both Australian and New Zealand.
Quantum dynamics of an electromagnetic mode that cannot contain
N
photons
Authors: Bretheau L. , Campagne-Ibarcq P. , Flurin E. , Mallet F. , Huard B.
Published: May 2015

Tailoring the quantum dynamics of light

The energy levels of a quantum system are determined by the laws of quantum mechanics and the specifics of the physical setting. Light confined to a cavity has energy levels neatly arranged in a “ladder” of equidistant rungs, each rung corresponding to a fixed number of photons. Bretheau
et al.
devised a way to limit the dynamics to only the lowest few rungs by coupling the system to a qubit, which shifted the energy of one of the higher rungs. When they then drove the system at a frequency corresponding to the distance between the rungs, only the states lower in energy than the shifted state could participate.

Science
, this issue p.
776
Newborn screening collides with privacy fears
Authors: Couzin-Frankel Jennifer
Published: May 2015

Informed consent requirement may change decades-old program.
Rules of the name
Authors: Kupferschmidt Kai
Published: May 2015

To avoid offense, WHO says no people, places, food, or animals in new disease names.
Graying Cuba strains socialist safety net
Authors: Stone Richard
Published: May 2015

Cuba's biotech success helped give rise to a rapidly aging population; now, its scientists are hoping to ease the disease burden in the golden years.
Cuba's coral Eden
Authors: Pennisi Elizabeth
Published: May 2015

Scientists rush to study what may be some of the last healthy corals in the Caribbean.
Comment on “Morality in everyday life”
Authors: Voelkle Manuel C.
Published: May 2015

In examining morality in everyday life, Hofmann
et al
. (Reports, 12 September 2014, p. 1340) conclude that being the target of (im)moral deeds impacts happiness, whereas committing them primarily affects one’s sense of purpose. I point to shortcomings in the analyses and interpretations and caution that, based on the methodological approach, conclusions about everyday life relationships between morality and happiness/purpose are premature.
Quasar quartet embedded in giant nebula reveals rare massive structure in distant universe
Authors: Hennawi Joseph F. , Prochaska J. Xavier , Cantalupo Sebastiano , Arrigoni-Battaia Fabrizio
Published: May 2015

In a cluster of protogalaxies far, far away

Astronomers constantly scour the sky for astronomical objects that can provide insight and constrain their models and simulations of galaxy evolution. Hennawi
et al.
surveyed the ancient sky at an epoch when the universe was half its age for nebulae: large clouds of ionized hydrogen. They stumbled across a system containing four active galactic nuclei, or quasars; objects that are thought to be the progenitors of galaxies. Finding a nebula with a rare quadruple quasar system embedded within it allows detailed spectroscopic and motional studies that may help to refine current models of galaxy and galaxy cluster formation.

Science
, this issue p.
779
Adventures in the Amazon
Naturalists in Paradise Wallace, Bates and Spruce in the Amazon
John Hemming
Thames and Hudson, 2015. 368 pp.
Authors: Knapp Sandra
Published: May 2015

For three intrepid Victorian naturalists, exploration and entrepreneurship went hand in hand.
Neo approaches to cancer vaccines
Authors: Delamarre Lélia , Mellman Ira , Yadav Mahesh
Published: May 2015

A neoantigen-based vaccine elicits T cell responses in cancer patients

[Also see Report by

Carreno
et al.

]
Evaluation of the HISCL Anti-Treponema pallidum Assay as a Screening Test for Syphilis
Authors: An Jingna , Chen Qixia , Liu Qianqian , Rao Chenli , Li Dongdong , Wang Tingting , Tao Chuanmin , Wang Lanlan
Published: May 2015

The resurgence of syphilis in recent years has become a serious threat to public health worldwide, and the serological detection of specific antibodies against
Treponema pallidum
remains the most reliable method for laboratory diagnosis of syphilis. This study examined the performance of the recently launched HISCL anti-
Treponema pallidum
(anti-TP) assay as a screening test for syphilis in a high-volume laboratory. The HISCL anti-TP assay was tested in 300 preselected syphilis-positive samples, 704 fresh syphilis-negative samples, 48 preselected potentially interfering samples, and 30 “borderline” samples and was compared head to head with the commercially available Lumipulse G TP-N. In this study, the HISCL anti-TP assay was in perfect agreement with the applied testing algorithms with an overall agreement of 100%, comparable to that of Lumipulse G TP-N (99.63%). The sensitivity and specificity of the HISCL anti-TP assay were 100% (95% confidence interval [CI], 98.42% to 100%) and 100% (95% CI, 99.37% to 100%), respectively. Considering the excellent ease of use and automation, high throughput, and its favorable sensitivity and specificity, the HISCL anti-TP assay may represent a new choice for syphilis screening in high-volume laboratories.
Vaccination with theospA- andospB-Negative Borrelia burgdorferi Strain 50772 Provides Significant Protection against Canine Lyme Disease
Authors: LaFleur Rhonda L. , Callister Steven M. , Dant Jennifer C. , Wasmoen Terri L. , Jobe Dean A. , Lovrich Steven D.
Published: May 2015

Beagles received placebo orospA- andospB-negativeBorrelia burgdorferibefore a tick challenge. A total of 28 (41%) ticks and skin biopsy specimens from each control dog (n= 10) containedB. burgdorferi. In contrast, 12 (19%) ticks recovered from the vaccine recipients (n= 10) were infected (P= 0.0077), and 5 dogs yielded spirochetes from the skin biopsy specimens (P= 0.0325). In addition, 9 (90%) placebo recipients and 4 (40%) vaccine recipients developed joint abnormalities (P= 0.0573). Therefore, vaccination with theospA- andospB-negative spirochete provided significant protection against Lyme disease.
Multicenter Clinical Evaluation of the Novel Alere i Strep A Isothermal Nucleic Acid Amplification Test
Authors: Cohen Daniel M. , Russo Michael E. , Jaggi Preeti , Kline Jennifer , Gluckman William , Parekh Amisha
Published: May 2015

Rapid detection of group A beta-hemolytic streptococcus (GAS) is used routinely to help diagnose and treat pharyngitis. However, available rapid antigen detection tests for GAS have relatively low sensitivity, and backup testing is recommended in children. Newer assays are more sensitive yet require excessive time for practical point-of-care use as well as laboratory personnel. The Alere i strep A test is an isothermal nucleic acid amplification test designed to offer highly sensitive results at the point of care within 8 min when performed by nonlaboratory personnel. The performance of the Alere i strep A test was evaluated in a multicenter prospective trial in a Clinical Laboratory Improvement Amendments (CLIA)-waived setting in comparison to bacterial culture in 481 children and adults. Compared to culture, the Aleri i strep A test had 96.0% sensitivity and 94.6% specificity. Discrepant results were adjudicated by PCR and found the Alere i strep A test to have 98.7% sensitivity and 98.5% specificity. Overall, the Alere i strep A test could provide a one-step, rapid, point-of-care testing method for GAS pharyngitis and obviate backup testing on negative results.
Use of the FilmArray System for Detection of Zaire ebolavirus in a Small Hospital in Bo, Sierra Leone
Authors: Leski Tomasz A. , Ansumana Rashid , Taitt Chris R. , Lamin Joseph M. , Bangura Umaru , Lahai Joseph , Mbayo George , Kanneh Mohamed B. , Bawo Ben , Bockarie Alfred S. , Scullion Matt , Phillips Cynthia L. , Horner Cynthia P. , Jacobsen Kathryn H. , Stenger David A.
Published: May 2015

Laboratories associated with small hospitals often have limited expertise, personnel, and equipment to rapidly identify rare and emerging infectious diseases. We describe the successful use of the FilmArray system for rapid detection of Ebola virus directly from clinical samples in 6 out of 83 tested subjects in a small health care center in Sierra Leone.
Epizootiological Investigation of Getah Virus Infection among Racehorses in Japan in 2014
Authors: Bannai Hiroshi , Nemoto Manabu , Ochi Akihiro , Kikuchi Takuya , Kobayashi Minoru , Tsujimura Koji , Yamanaka Takashi , Kondo Takashi
Published: May 2015

To clarify the factors causing an outbreak in 2014 of Getah virus infection among racehorses at the Miho training center, Japan, we isolated virus strains and performed an epizootiological investigation of affected horses and related horse populations. Three Getah virus isolates were recovered from clinical samples, and one of them (14-I-605) was used in a virus-neutralizing test. Of the affected horses (
n
= 33), 20 (60.6%) were 2-year-olds. We investigated the histories of Getah virus vaccination of the affected horses and the whole population at the Miho training center. Among the 2-year-old population, the prevalence of the disease in horses that had been vaccinated once was 14.1%. This was significantly higher than that in horses that had been vaccinated twice or more (1.3%;
P
< 0.01). Among horses that had entered the training center from farms in Ibaraki Prefecture surrounding the training center and from neighboring Chiba Prefecture, the rate of seropositivity for Getah virus was 13.0% in September 2014 and 42.9% in October 2014; that in the corresponding periods in 2010 and 2013 was 0%. In conclusion, we identified two possible causes of the outbreak of Getah virus infection in the training center in 2014: (i) the existence of susceptible horses that had received only one dose of vaccination before the outbreak and (ii) increased risk of exposure to the virus because of epizootic Getah virus infection among horses on surrounding farms in Ibaraki and Chiba prefectures.
Proton Nuclear Magnetic Resonance Spectroscopy as a Technique for Gentamicin Drug Susceptibility Studies with Escherichia coli ATCC 25922
Authors: García-Álvarez Lara , Busto Jesús H. , Avenoza Alberto , Sáenz Yolanda , Peregrina Jesús Manuel , Oteo José A.
Published: May 2015

Antimicrobial drug susceptibility tests involving multiple time-consuming steps are still used as reference methods. Today, there is a need for the development of new automated instruments that can provide faster results and reduce operating time, reagent costs, and labor requirements. Nuclear magnetic resonance (NMR) spectroscopy meets those requirements. The metabolism and antimicrobial susceptibility ofEscherichia coliATCC 25922 in the presence of gentamicin have been analyzed using NMR and compared with a reference method. Direct incubation of the bacteria (with and without gentamicin) into the NMR tube has also been performed, and differences in the NMR spectra were obtained. The MIC, determined by the reference method found in this study, would correspond with the termination of the bacterial metabolism observed with NMR. Experiments carried out directly into the NMR tube enabled the development of antimicrobial drug susceptibility tests to assess the effectiveness of the antibiotic. NMR is an objective and reproducible method for showing the effects of a drug on the subject bacterium and can emerge as an excellent tool for studying bacterial activity in the presence of different antibiotic concentrations.
Impact of Mucorales and Other Invasive Molds on Clinical Outcomes of Polymicrobial Traumatic Wound Infections
Authors: Warkentien Tyler E. , Shaikh Faraz , Weintrob Amy C. , Rodriguez Carlos J. , Murray Clinton K. , Lloyd Bradley A. , Ganesan Anuradha , Aggarwal Deepak , Carson M. Leigh , Tribble David R.
Published: May 2015

Combat trauma wounds with invasive fungal infections (IFIs) are often polymicrobial with fungal and bacterial growth, but the impact of the wound microbiology on clinical outcomes is uncertain. Our objectives were to compare the microbiological features between IFI and non-IFI wounds and evaluate whether clinical outcomes differed among IFI wounds based upon mold type. Data from U.S. military personnel injured in Afghanistan with IFI wounds were examined. Controls were matched by the pattern/severity of injury, including blood transfusion requirements. Wound closure timing was compared between IFI and non-IFI control wounds (with/without bacterial infections). IFI wound closure was also assessed according to mold species isolation. Eighty-two IFI wounds and 136 non-IFI wounds (63 with skin and soft tissue infections [SSTIs] and 73 without) were examined. The time to wound closure was longer for the IFI wounds (median, 16 days) than for the non-IFI controls with/without SSTIs (medians, 12 and 9 days, respectively;
P
< 0.001). The growth of multidrug-resistant Gram-negative rods was reported among 35% and 41% of the IFI and non-IFI wounds with SSTIs, respectively. Among the IFI wounds, times to wound closure were significantly longer for wounds with
Mucorales
growth than for wounds with non-
Mucorales
growth (median, 17 days versus 13 days;
P
< 0.01). When wounds with
Mucorales
and
Aspergillus
spp. growth were compared, there was no significant difference in wound closure timing. Trauma wounds with SSTIs were often polymicrobial, yet the presence of invasive molds (predominant types: order
Mucorales
,
Aspergillus
spp., and
Fusarium
spp.) significantly prolonged the time to wound closure. Overall, the times to wound closure were longest for the IFI wounds with
Mucorales
growth.
Respiratory Syncytial Virus Infection Upregulates NLRC5 and Major Histocompatibility Complex Class I Expression through RIG-I Induction in Airway Epithelial Cells
Authors: Guo Xuancheng , Liu Taixiang , Shi Hengfei , Wang Jingjing , Ji Ping , Wang Hongwei , Hou Yayi , Tan Ren Xiang , Li Erguang
Published: May 2015

Respiratory syncytial virus (RSV) is the leading cause of acute respiratory tract viral infection in infants, causing bronchiolitis and pneumonia. The host antiviral response to RSV acts via retinoic acid-inducible gene I (RIG-I). We show here that RSV infection upregulates major histocompatibility complex class I (MHC-I) expression through the induction of NLRC5, a NOD-like, CARD domain-containing intracellular protein that has recently been identified as a class I MHC transactivator (CITA). RSV infection of A549 cells promotes upregulation of NLRC5 via beta interferon (IFN-β) production, since the NLRC5-inducing activity in a conditioned medium from RSV-infected A549 cells was removed by antibody to IFN-β, but not by antibody to IFN-γ. RSV infection resulted in RIG-I upregulation and induction of NLRC5 and MHC-I. Suppression of RIG-I induction significantly blocked NLRC5, as well as MHC-I, upregulation and diminished IRF3 activation. Importantly, Vero cells deficient in interferon production still upregulated MHC-I following introduction of the RSV genome by infection or transfection, further supporting a key role for RIG-I. A model is therefore proposed in which the host upregulates MHC-I expression during RSV infection directly via the induction of RIG-I and NLRC5 expression. Since elevated expression of MHC-I molecules can sensitize host cells to T lymphocyte-mediated cytotoxicity or immunopathologic damage, the results have significant implications for the modification of immunity in RSV disease.

IMPORTANCEHuman respiratory syncytial virus (RSV) is the leading cause of bronchiolitis and pneumonia in infants and young children worldwide. Infection early in life is linked to persistent wheezing and allergic asthma in later life, possibly related to upregulation of major histocompatibility class I (MHC-I) on the cell surface, which facilitates cytotoxic T cell activation and antiviral immunity. Here, we show that RSV infection of lung epithelial cells induces expression of RIG-I, resulting in induction of a class I MHC transactivator, NLRC5, and subsequent upregulation of MHC-I. Suppression of RIG-I induction blocked RSV-induced NLRC5 expression and MHC-I upregulation. Increased MHC-I expression may exacerbate the RSV disease condition due to immunopathologic damage, linking the innate immune response to RSV disease.
A Single Point Mutation Creating a Furin Cleavage Site in the Spike Protein Renders Porcine Epidemic Diarrhea Coronavirus Trypsin Independent for Cell Entry and Fusion
Authors: Li Wentao , Wicht Oliver , van Kuppeveld Frank J. M. , He Qigai , Rottier Peter J. M. , Bosch Berend-Jan
Published: May 2015

The emerging porcine epidemic diarrhea virus (PEDV) requires trypsin supplementation to activate its S protein for membrane fusion and virus propagation in cell culture. By substitution of a single amino acid in the S protein, we created a recombinant PEDV with an artificial furin protease cleavage site N terminal of the putative fusion peptide (PEDV-S
FCS
). PEDV-S
FCS
exhibited trypsin-independent cell-cell fusion and was able to replicate in culture cells independently of trypsin, though to low titer.
Phage Therapy: a Step Forward in the Treatment of Pseudomonas aeruginosa Infections
Authors: Pires Diana P. , Vilas Boas Diana , Sillankorva Sanna , Azeredo Joana
Published: May 2015

Antimicrobial resistance constitutes one of the major worldwide public health concerns. Bacteria are becoming resistant to the vast majority of antibiotics, and nowadays, a common infection can be fatal. To address this situation, the use of phages for the treatment of bacterial infections has been extensively studied as an alternative therapeutic strategy. Since
Pseudomonas aeruginosa
is one of the most common causes of health care-associated infections, many studies have reported the
in vitro
and
in vivo
antibacterial efficacy of phage therapy against this bacterium. This review collects data of all the
P. aeruginosa
phages sequenced to date, providing a better understanding about their biodiversity. This review further addresses the
in vitro
and
in vivo
results obtained by using phages to treat or prevent
P. aeruginosa
infections as well as the major hurdles associated with this therapy.
High-Throughput Analysis of Human Cytomegalovirus Genome Diversity Highlights the Widespread Occurrence of Gene-Disrupting Mutations and Pervasive Recombination
Authors: Sijmons Steven , Thys Kim , Mbong Ngwese Mirabeau , Van Damme Ellen , Dvorak Jan , Van Loock Marnix , Li Guangdi , Tachezy Ruth , Busson Laurent , Aerssens Jeroen , Van Ranst Marc , Maes Piet
Published: May 2015

Human cytomegalovirus is a widespread pathogen of major medical importance. It causes significant morbidity and mortality in immunocompromised individuals, and congenital infections can result in severe disabilities or stillbirth. Development of a vaccine is prioritized, but no candidate is close to release. Although correlations of viral genetic variability with pathogenicity are suspected, knowledge about the strain diversity of the 235-kb genome is still limited. In this study, 96 full-length human cytomegalovirus genomes from clinical isolates were characterized, quadrupling the amount of information available for full-genome analysis. These data provide the first high-resolution map of human cytomegalovirus interhost diversity and evolution. We show that cytomegalovirus is significantly more divergent than all other human herpesviruses and highlight hot spots of diversity in the genome. Importantly, 75% of strains are not genetically intact but contain disruptive mutations in a diverse set of 26 genes, including the immunomodulatory genes UL40 and UL111A. These mutants are independent of culture passage artifacts and circulate in natural populations. Pervasive recombination, which is linked to the widespread occurrence of multiple infections, was found throughout the genome. The recombination density was significantly higher than those of other human herpesviruses and correlated with strain diversity. While the overall effects of strong purifying selection on virus evolution are apparent, evidence of diversifying selection was found in several genes encoding proteins that interact with the host immune system, including UL18, UL40, UL142, and UL147. These residues may present phylogenetic signatures of past and ongoing virus-host interactions.

IMPORTANCE
Human cytomegalovirus has the largest genome of all viruses that infect humans. Currently, there is a great interest in establishing associations between genetic variants and strain pathogenicity of this herpesvirus. Since the number of publicly available full-genome sequences is limited, knowledge about strain diversity is highly fragmented and biased toward a small set of loci. Combined with our previous work, we have now contributed 101 complete genome sequences. We have used these data to conduct the first high-resolution analysis of interhost genome diversity, providing an unbiased and comprehensive overview of cytomegalovirus variability. These data are of major value to the development of novel antivirals and a vaccine and to identify potential targets for genotype-phenotype experiments. Furthermore, these data have enabled a thorough study of the evolutionary processes that have shaped cytomegalovirus diversity.
Molecular Mechanism for LAMP1 Recognition by Lassa Virus
Authors: Cohen-Dvashi Hadas , Cohen Nadav , Israeli Hadar , Diskin Ron
Published: May 2015

Lassa virus is a notorious human pathogen that infects many thousands of people each year in West Africa, causing severe viral hemorrhagic fevers and significant mortality. The surface glycoprotein of Lassa virus mediates receptor recognition through its GP1 subunit. Here we report the crystal structure of GP1 from Lassa virus, which is the first representative GP1 structure for Old World arenaviruses. We identify a unique triad of histidines that forms a binding site for LAMP1, a known lysosomal protein recently discovered to be a critical receptor for internalized Lassa virus at acidic pH. We demonstrate that mutation of this histidine triad, which is highly conserved among Old World arenaviruses, impairs LAMP1 recognition. Our biochemical and structural data further suggest that GP1 from Lassa virus may undergo irreversible conformational changes that could serve as an immunological decoy mechanism. Together with a variable region that we identify on the surface of GP1, those could be two distinct mechanisms that Lassa virus utilizes to avoid antibody-based immune response.

IMPORTANCE
Structural data at atomic resolution for viral proteins is key for understanding their function at the molecular level and can facilitate novel avenues for combating viral infections. Here we used X-ray protein crystallography to decipher the crystal structure of the receptor-binding domain (GP1) from Lassa virus. This is a pathogenic virus that causes significant illness and mortality in West Africa. This structure reveals the overall architecture of GP1 domains from the group of viruses known as the Old World arenaviruses. Using this structural information, we elucidated the mechanisms for pH switch and binding of Lassa virus to LAMP1, a recently identified host receptor that is critical for successful infection. Lastly, our structural analysis suggests two novel immune evasion mechanisms that Lassa virus may utilize to escape antibody-based immune response.
Isolation and Analysis of Rare Norovirus Recombinants from Coinfected Mice Using Drop-Based Microfluidics
Authors: Zhang Huidan , Cockrell Shelley K. , Kolawole Abimbola O. , Rotem Assaf , Serohijos Adrian W. R. , Chang Connie B. , Tao Ye , Mehoke Thomas S. , Han Yulong , Lin Jeffrey S. , Giacobbi Nicholas S. , Feldman Andrew B. , Shakhnovich Eugene , Weitz David A. , Wobus Christiane E. , Pipas James M.
Published: May 2015

Human noroviruses (HuNoVs) are positive-sense RNA viruses that can cause severe, highly infectious gastroenteritis. HuNoV outbreaks are frequently associated with recombination between circulating strains. Strain genotyping and phylogenetic analyses show that noroviruses often recombine in a highly conserved region near the junction of the viral polyprotein (open reading frame 1 [ORF1]) and capsid (ORF2) genes and occasionally within the RNA-dependent RNA polymerase (RdRP) gene. Although genotyping methods are useful for tracking changes in circulating viral populations, they report only the dominant recombinant strains and do not elucidate the frequency or range of recombination events. Furthermore, the relatively low frequency of recombination in RNA viruses has limited studies to cell culture or
in vitro
systems, which do not reflect the complexities and selective pressures present in an infected organism. Using two murine norovirus (MNV) strains to model coinfection, we developed a microfluidic platform to amplify, detect, and recover individual recombinants following
in vitro
and
in vivo
coinfection. One-step reverse transcriptase PCR (RT-PCR) was performed in picoliter drops with primers that identified the wild-type and recombinant progenies and scanned for recombination breakpoints at ∼1-kb intervals. We detected recombination between MNV strains at multiple loci spanning the viral protease, RdRP, and capsid ORFs and isolated individual recombinant RNA genomes that were present at a frequency of 1/300,000 or higher. This study is the first to examine norovirus recombination following coinfection of an animal and suggests that the exchange of RNA among viral genomes in an infected host occurs in multiple locations and is an important driver of genetic diversity.

IMPORTANCE
RNA viruses increase diversity and escape host immune barriers by genomic recombination. Studies using a number of viral systems indicate that recombination occurs via template switching by the virus-encoded RNA-dependent RNA polymerase (RdRP). However, factors that govern the frequency and positions of recombination in an infected organism remain largely unknown. This work leverages advances in the applied physics of drop-based microfluidics to isolate and sequence rare recombinants arising from the coinfection of mice with two distinct strains of murine norovirus. This study is the first to detect and analyze norovirus recombination in an animal model.
Ability of the Encephalitic Arbovirus Semliki Forest Virus To Cross the Blood-Brain Barrier Is Determined by the Charge of the E2 Glycoprotein
Authors: Ferguson Mhairi C. , Saul Sirle , Fragkoudis Rennos , Weisheit Sabine , Cox Jonathan , Patabendige Adjanie , Sherwood Karen , Watson Mick , Merits Andres , Fazakerley John K.
Published: May 2015

Semliki Forest virus (SFV) provides a well-characterized model system to study the pathogenesis of virus encephalitis. Several studies have used virus derived from the molecular clone SFV4. SFV4 virus does not have the same phenotype as the closely related L10 or the prototype virus from which its molecular clone was derived. In mice, L10 generates a high-titer plasma viremia, is efficiently neuroinvasive, and produces a fatal panencephalitis, whereas low-dose SFV4 produces a low-titer viremia, rarely enters the brain, and generally is avirulent. To determine the genetic differences responsible, the consensus sequence of L10 was determined and compared to that of SFV4. Of the 12 nucleotide differences, six were nonsynonymous; these were engineered into a new molecular clone, termed SFV6. The derived virus, SFV6, generated a high-titer viremia and was efficiently neuroinvasive and virulent. The phenotypic difference mapped to a single amino acid residue at position 162 in the E2 envelope glycoprotein (lysine in SFV4, glutamic acid in SFV6). Analysis of the L10 virus showed it contained different plaque phenotypes which differed in virulence. A lysine at E2 247 conferred a small-plaque avirulent phenotype and glutamic acid a large-plaque virulent phenotype. Viruses with a positively charged lysine at E2 162 or 247 were more reliant on glycosaminoglycans (GAGs) to enter cells and were selected for by passage in BHK-21 cells. Interestingly, viruses with the greatest reliance on binding to GAGs replicated to higher titers in the brain and more efficiently crossed anin vitroblood-brain barrier (BBB).

IMPORTANCEVirus encephalitis is a major disease, and alphaviruses, as highlighted by the recent epidemic of chikungunya virus (CHIKV), are medically important pathogens. In addition, alphaviruses provide well-studied experimental systems with extensive literature, many tools, and easy genetic modification. In this study, we elucidate the genetic basis for the difference in phenotype between SFV4 and the virus stocks from which it was derived and correct this by engineering a new molecular clone. We then use this clone in one comprehensive study to demonstrate that positively charged amino acid residues on the surface of the E2 glycoprotein, mediated by binding to GAGs, determine selective advantage and plaque size in BHK-21 cells, level of viremia in mice, ability to cross an artificial BBB, efficiency of replication in the brain, and virulence. Together with studies on Sindbis virus (SINV), this study provides an important advance in understanding alphavirus, and probably other virus, encephalitis.
Mutations in the Borrelia burgdorferi Flagellar Type III Secretion System Genes
fliH
and
fliI
Profoundly Affect Spirochete Flagellar Assembly, Morphology, Motility, Structure, and Cell Division
Authors: Lin Tao , Gao Lihui , Zhao Xiaowei , Liu Jun , Norris Steven J.
Published: May 2015

The Lyme disease spirochete
Borrelia burgdorferi
migrates to distant sites in the tick vectors and mammalian hosts through robust motility and chemotaxis activities. FliH and FliI are two cytoplasmic proteins that play important roles in the type III secretion system (T3SS)-mediated export and assembly of flagellar structural proteins. However, detailed analyses of the roles of FliH and FliI in
B. burgdorferi
have not been reported. In this study,
fliH
and
fliI
transposon mutants were utilized to dissect the mechanism of the
Borrelia
type III secretion system. The
fliH
and
fliI
mutants exhibited rod-shaped or string-like morphology, greatly reduced motility, division defects (resulting in elongated organisms with incomplete division points), and noninfectivity in mice by needle inoculation. Mutants in
fliH
and
fliI
were incapable of translational motion in 1% methylcellulose or soft agar. Inactivation of either
fliH
or
fliI
resulted in the loss of the FliH-FliI complex from otherwise intact flagellar motors, as determined by cryo-electron tomography (cryo-ET). Flagellar assemblies were still present in the mutant cells, albeit in lower numbers than in wild-type cells and with truncated flagella. Genetic complementation of
fliH
and
fliI
mutants in
trans
restored their wild-type morphology, motility, and flagellar motor structure; however, full-length flagella and infectivity were not recovered in these complemented mutants. Based on these results, disruption of either
fliH
or
fliI
in
B. burgdorferi
results in a severe defect in flagellar structure and function and cell division but does not completely block the export and assembly of flagellar hook and filament proteins.

IMPORTANCE
Many bacteria are able to rapidly transport themselves through their surroundings using specialized organelles called flagella. In spiral-shaped organisms called spirochetes, flagella act like inboard motors and give the bacteria the ability to bore their way through dense materials (such as human tissue) in a corkscrew manner. In this article, we studied how two proteins, called FliH and FliI, are important for the production of full-length flagella in the Lyme disease spirochete
Borrelia burgdorferi
. Mutants with defective production of FliH and FliI have reduced flagellar length and motility; this deficiency in turn affects many aspects of
B. burgdorferi
's biology, including the ability to undergo cell division and cause disease in mammals. Using a microscopic computed tomography (CT) scan approach called cryo-electron tomography, the structure that contains FliH and FliI was defined in the context of the flagellar motor, providing clues regarding how this amazing nanomachine is assembled and functions.
Spontaneous Electrical Activities at Myofascial Trigger Points at Different Stages of Recovery from Injury in a Rat Model
Authors: Huang Qiang-Min , Lv Jiao-Jiao , Ruanshi Qiong-Mei , Liu Lin
Published: May 2015

Background

Spontaneous electrical activity (SEA) is a feature of myofascial trigger points (MTrPs), which can either be latent or active. However, SEA at different stages of recovery from MTrPs remains unclear.

Objective

To investigate the temporal changes in the nature of SEA after generation of MTrPs in a rat model.

Methods

32 rats were divided into four groups: 24 rats were assigned to experimental groups (EGs), which underwent the MTrP modelling intervention and 8 were allocated to a control group (CG). All EG rats received a blunt strike to the left vastus medialis combined with eccentric exercise for 8 weeks. After modelling, the EG rats were subdivided into three groups with total recovery times of 4, 8 and 12 weeks (EG-4w, EG-8w and EG-12w, respectively). Taut bands (TBs) with and without the presence of active MTrPs were identified in the left hind limb muscles of all rats, verified by SEA and further examined with electromyography recordings. Myoelectrical signals were also categorised into one of five types.

Results

CG rats had fewer TBs than EG rats and EGs showed variable frequencies of SEA. SEA frequencies were higher in EG-4w than in EG-8w and EG-12w groups (240.57±72.9 vs 168.14±64.5 and 151.63±65.4, respectively, p<0.05) and were significantly greater in all EGs than in the CG (55.75±21.9). Relative to CG rats, amplitudes and durations of electrical potentials in the EG were only increased in the EG-8w and EG-12w groups. Types IV and V myoelectrical signals were never seen in latent MTrPs and type V signals did not occur in EG-4w rats.

Conclusions

Increasing recovery periods following a MTrP modelling intervention in rats are characterised by different frequencies and amplitudes of SEA from TBs.

Trial Registration Number

2014012.
No medicine is sometimes the best medicine
Authors: Wallis Katharine Ann
Published: May 2015

A 76-year-old woman was admitted to hospital from the rheumatology outpatient clinic for investigation of fatigue, malaise, emotional lability, muscle weakness, productive cough and postural hypotension. She had been taking prednisone 60–40 mg daily for 6 weeks for suspected giant cell arteritis, along with six other regular medications, and had recently finished a course of antibiotics. During her admission she underwent many investigations (mostly negative) and treatments (largely harmful). When the diagnosis of adverse drug reaction was eventually reached, her medications were withdrawn and her symptoms gradually resolved. She was discharged home 1 month after admission, vowing never to return following her ‘stormy course’. Adverse drug reactions are a common cause of avoidable hospital admissions in the elderly, estimated to cost billions every year. The single greatest risk factor for adverse drug reactions is the number of medications a person takes. Deprescribing to reduce potentially inappropriate medication is a possible way forward.
Trans-radial approach for coronary angiography in an adult postoperative patient with tetralogy of Fallot with complex anatomy
Authors: Rahman Nasir , Gul Ibrahim , Ali Ashique
Published: May 2015

A 42-year-old, postoperative patient with tetralogy of Fallot (TOF) with right-sided aortic arch, presented with heart failure secondary to left ventricular dysfunction, severe valvular regurgitation and residual ventricular septal defect (VSD). After initial stabilisation, he underwent successful coronary angiography through a trans-radial approach followed by aortic valve replacement, pulmonary valve and VSD repair, and was discharged home in stable condition. This case report highlights the trans-radial approach as a feasible option for coronary angiography in postoperative patients with TOF with right-sided aortic arch.