bluuebunny/crossref_metadata_2025 huggingface dataset:
The Microstructural Response of Articular Cartilage at Peak Internal Pore Pressure: A Comparison Between Normal and Degenerate Matrices
Authors: Fick James M. , Thambyah Ashvin , Broom Neil D.
Published: March 2014

This study was aimed at investigating the relationship between the microstructural responses of healthy (normal) versus mildly osteoarthritic articular cartilage and their associated peak internal pore pressures, when subjected to direct compression.
Biphasic Viscoelastic Properties of Human TMJ Disc
Authors: Kuo Jonathan Y. , Bacro Thierry , Yao Hai
Published: March 2014

The temporomandibular joint (TMJ) is a load-bearing joint consisting of the condyle of the mandibular bone, the fossa eminence of the temporal bone, and a fibrocartilaginous disc wedged in between the bone surfaces (Figure 1A). The TMJ disc serves to distribute stress, lubricate movement, and protect the articular surfaces of the joint. The TMJ disc is a viscoelastic material consisting of two principle phases: a solid matrix composed mainly of collagen and proteoglycan, and a fluid phase primarily comprised of interstitial fluid.
In Vitro Simulation of Deep Knee Flexion Using Static and Dynamic Machines
Authors: Maletsky Lorin P. , Clary Chadd W. , Guess Trent M. , Mane Amit M. , Reeve Amber N.
Published: March 2014

Experimental testing with cadaveric tissue allows the application of controlled loads and/or motions while still maintaining the inherent variability in the anatomy and soft tissue of the specimens. Multi-axial dynamic loading of tissue allows for experiments to be conducted that simulate conditions approaching physiological. Knee simulators have been used to generate physiological loading on the human knee to study kinematics, soft tissue loading, and joint contact pressure. These machines have been used to investigate injury, surgical outcomes, and prosthetic design. While there are a number of different geometries for knee loading devices, most are based on the Oxford rig design [1] with a vertical orientation of the leg where the hip is able to translate up and down while allowing flexion at the hip, knee, and ankle. The foot or ankle can have a variety of constraints and degrees of freedom. One of the recent areas of interest in knee biomechanics is the role different structures of the knee play during deep knee flexion activities. This is of particular interest to the orthopedic industry because of the common complaint regarding a feeling of a loss of stability during high flexion activities for post-TKR patients and the prevalence of high-flexion activities in emerging worldwide markets. The objective of this abstract is to describe two knee loading devices that have been used to study knee biomechanics, and most recently high flexion motion, and present some representative data from these tools.
Towards Anhydrous Preservation: Osmotic Analysis of Cell Drying
Authors: Chakraborty Nilay , Elliott Gloria
Published: March 2014

Dry preservation involves removing water from a sample so that molecular mobility is decreased and degradative biochemical processes are slowed. Recently this approach has been explored as an energy-efficient alternative to cryopreservation of mammalian cells. Hurdles to the successful dry preservation of cells include quantification problems associated with non-uniform dehydration processes and the high sensitivity of mammalian cells to osmotic stress.
Effects of Endplate and Mechanical Loading on Solute Transport in Intervertebral Disc
Authors: Wu Yongren , Glaser John , Yao Hai
Published: March 2014

The intervertebral disc (IVD) is the largest cartilaginous structure in human body that contributes to flexibility and load support in the spine. To accomplish these functions, the disc has a unique architecture consisting of a centrally-located nucleus pulposus (NP) surrounded superiorly and inferiorly by cartilage endplates (CEP) and peripherally by the annulus fibrosus (AF). Disc degeneration is strongly linked to low back pain. Poor nutrient supply has been suggested as a potential mechanism for disc degeneration. Previous theoretical studies have shown that the distributions of nutrients and metabolites (e.g., oxygen, glucose, and lactate) within the IVD depended on tissue diffusivities, nutrient supply, and cellular metabolic rates [1, 2]. Based on a multiphasic mechano-electrochemical finite element model of human IVD [3], our recent theoretical study suggested that the mechanical loading has little effect on small solute transport (e.g., glucose), but significantly affects large solute transport (e.g., growth factor). The objective of this study was to further develop the multiphasic finite element model of IVD by including the cartilage endplate and considering the nutrient consumption of disc cells. Using this model, the effects of endplate and mechanical loading on solute transport in IVD were examined.
Effect of Sidegroup on Mechanical Properties of Acrylate Networks for Biomedical Applications
Authors: Safranski David , Gall Ken
Published: March 2014

The purpose of this study was to understand how the side group dictates thermo-mechanical properties of shape-memory acrylate networks, specifically strain to failure and toughness. A useful parameter in assessing shape memory polymers is the strain to failure because it is critical to know how much recovery strain the material can experience. To understand how the structure is related to mechanical properties, such as strain to failure, materials of differing chain stiffness ratio, C∞, were compared at varying percentages of crosslinker. While the chemical and thermal properties of acrylate networks have been discussed in much detail, methods of toughening networks by the precise choice of certain acrylates have not been thoroughly examined. In order for these networks to be of practical use as biomedical devices, such as minimally invasive shape memory polymer stents, detailed structure-property relationships must be established.
Identification of Possibly Unsafe RF Exposure Thresholds for Humans Using Porcine Models
Authors: Shrivastava Devashish , Kulesa Jeramy , DelaBarre Lance , Snyder Carl , Hanson Timothy , Vaughan J. Thomas
Published: March 2014

Thresholds for safe radio-frequency (RF) power exposure are unknown in humans. Identification of safe RF power dose thresholds is important for human safety since humans are exposed to RF environment in multiple applications. (1–5) To identify possible unsafe RF energy deposition limits in humans, in vivo temperature responses were measured in the scalp and brain of eight human-sized porcine models.
Porohyperelastic Simulation of Abdominal Aortic Aneurysms
Authors: Ayyalasomayajula Avinash , Simon Bruce R. , Vande Geest Jonathan P.
Published: March 2014

Abdominal aortic aneurysm (AAA) is a progressive dilation of the infrarenal aorta and results in a significant alteration in local hemodynamic environment [1]. While an aneurysmal diameter of 5.5cm is typically classified as being of high risk, recent studies have demonstrated that maximum wall stress could be a better indicator of an AAA rupture than maximum diameter [2]. The wall stress is greatly influenced by the blood pressure, aneurysm diameter, shape, wall thickness and the presence of thrombus. The work done by Finol et al. suggested that hemodynamic pressure variations have an insignificant effect on AAA wall stress and that primarily the shape of the aneurysm determines the stress distribution. They noted that for peak wall stress studies the static pressure conditions would suffice as the in vivo conditions. Wang et al have developed an isotropic hyperelastic constitutive model for the intraluminal thrombus (ILT). Such models have been used to study the stress distributions in patient specific AAAs [3, 4].
Implementation of a Real-Time Telerobotic System for Generating an Assistive Force Feedback for Rehabilitation Applications
Authors: Veras Eduardo , Khokar Karan , De Laurentis Kathryn , Dubey Rajiv
Published: March 2014

In this paper we describe the implementation of a system that gives assistive force feedback to the remote user in a teleoperation based environment. The force feedback would help the user in trajectory following exercises for stroke rehabilitation. Exercises in virtual environments on a PC as well as real world exercises with a remote robotic arm, that would follow a trajectory in real-time as the user moves the master device, could be performed. Such real world exercises augmented with real-time force feedback can make the exercises more effective as the user gets force assistance along the desired path. Moreover, the system can find its application in remote therapy, where the therapist is away from the user, as it can be teleoperated and has internet based protocols. The assistive force feedback has been implemented using simple sensors such as the camera and the laser and a PC-based real-time multithreaded control system. The real-time force feedback from the remote robot to the master device has been possible using effective multithreading programming strategies in the control system design and novel sensor integration. The system also has the capabilities of autonomous as well as supervisory control of the remote robot and is modular as far as integration of different master devices for stroke rehabilitation exercises is concerned.
Motion Analysis of Transradial Prosthesis While Lifting a Box for Development of a Biomechanical Model
Authors: Carey Stephanie L. , Highsmith M. Jason , Dubey Rajiv V.
Published: March 2014

In order to design a prosthetic device, it is essential to analyze the movements of the limb that it is replacing. For improvement of prosthetic design, it is important to understand the limitations of current designs. The main purpose of this study was to evaluate the kinematic and the kinetics of transradial prosthesis users while bliaterally lifting a box, for experimental input of a biomechanical model. Creating a model for the movements of a transradial prosthesis can lead to its design improvement, selection criteria and virtual reality training.
Adaptation of a Knee Joint Testing System to Testing of the Spine
Authors: Bach Joel M. , Baldini Todd H.
Published: March 2014

The first generation of the knee load application system was developed at the University of California, Davis under the direction of Professor Maury Hull. This apparatus has been described in several abstracts and was published in 1995 [1]. This original system continues to be used by Dr. Hull and associates.
The Effect of Fiber Microstructure on the Observed Poisson’s Ratio of Tendon and Ligament Tissue
Authors: Reese Shawn P. , Maas Steve A. , Henninger Heath A. , Weiss Jeffrey A.
Published: March 2014

During tensile testing along the predominant collagen fiber direction, ligament and tendon tissue exhibit large Poisson’s ratios ranging from 1.3 in capsular ligament to 2.98 in flexor tendon [1][2]. Although the microstructure of these tissues (especially fiber crimp) has been characterized, the relationship between microstructure and Poisson’s ratio is relatively unexplored. There has been debate regarding the exact nature of the characteristic crimp within tendon fibers, however the two views most present in the literature are that of planar crimp and helical crimp. The aim of this study was to perform a finite element analysis on prototypical models of fibril bundles for both forms of crimp under tensile loading conditions. It was hypothesized that planar crimp alone would be insufficient for generating large Poisson’s ratios, and that some other microstructure (such as a helix) would be required.
Dynamic Joint Force Simulator
Authors: Farmer Ryan N. , Hendricks Kelly , McIff Terence E.
Published: March 2014

The majority of component testing machines available today are multiple axial wear simulators that focus on the interaction between two articular surfaces [1, 2, 3]. The stability of the implant in the bone, another factor in joint replacement survival is usually tested using unvarying biaxial fatigue loading [4]. These loading protocols do not replicate physiological loading conditions. We designed the Dynamic Joint Force Simulator (DJFS) to have the capability to apply physiological loads through an articular surface for the purpose of studying implant stability.
Mechanics and Cytocompatibility of Genipin Crosslinked Type I Collagen Nanofibrous Scaffolds
Authors: Gee Albert O. , Baker Brendon M. , Mauck Robert L.
Published: March 2014

Collagen is a principal constituent of the extracellular matrix (ECM) and as such, defines the microenvironmental milieu in which cells reside. In fiber-reinforced musculoskeletal tissues, collagen fibers are highly organized and generate the direction-dependent mechanical properties critical to the function of these structures. Given its primary role, collagen is particularly attractive for tissue engineering (TE) applications where scaffolds are coupled with cells to repair or regenerate damaged tissues. One method for producing collagen-based scaffolds is through electrospinning. This technique yields nano- to micron-scale fibers similar in diameter to those of the native ECM. Towards engineering orthopaedic tissues, methods have been devised to electrospin fibers into aligned arrays that can recapitulate the anisotropy of fiber-reinforced tissues [1]. While a number of polymers have been electrospun, collagen-based scaffolds are especially promising as they provide a biomimetic interface for cell attachment [2]. Numerous investigators have electrospun collagen [3], one major drawback is their inherent instability in aqueous environments. To address this, various crosslinking agents including glutaraldehyde (GA), 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide hydrochloride, and N-hydroxysuccinimide chemistries have been used, but these chemicals often prove cytotoxic or excessively laborious in application [4]. Even with crosslinking, dry as-formed nanofibrous collagen scaffolds with moduli greater than 50MPa diminish by 100-fold with rehydration [5].
Determining the Mechanical Properties of Coronary Sinus for Percutaneous Mitral Valve Repair
Authors: Pham Thuy M. , Nguyen Xuan H. , DeHerrera Milton , Sun Wei
Published: March 2014

Mitral valve regurgitation, the leakage of blood back to the left atrium during systole, is a significant cause of morbidity and mortality. The current treatment options for symptomatic mitral regurgitation are mitral valve replacement and mitral valve repair. However, the operative mortality for both of these treatments remains substantial[1]. Furthermore, these treatments are often not referred for elderly patients with comorbidities. Thus, there is a pressing need for less invasive, non-surgical treatments of mitral regurgitation.
Inhibitory Effect of Mechanical Load on IL-1 Induced Cartilage Degradation Is Mediated by Interferon-Gamma and IL-1 Receptor 1
Authors: Chen C. T. , Park S. , Bhargava M. , Torzilli P. A.
Published: March 2014

Matrix remodeling in articular cartilage is regulated by the elevation and activation of aggrecanases (ADAMTS-4 and ADAMTS-5) and matrix metalloproteinases (MMPs) [2–4, 7–9, 10]. Several recent studies from our and other groups have shown that mechanical loading can counteract interleukin 1 (IL-1) induced pro-inflammatory and catabolic events by down-regulating aggrecanases, MMPs, and pro-inflammatory genes [1, 3, 5, 6], but the molecular mechanism is not clear. Many previous studies have shown that the regulation of pro-inflammatory effect of IL-1 come from several aspects: anti-inflammatory cytokines (TGF-β, IL-10, IL-6 and interferon γ), IL-1 receptor related proteins (IL-1R1, IL-1R2, and IL-1Ra) as well as a family of intracellular inhibitory protein called Suppressor Of Cytokine Signaling (SOCS.) SOCS1 and SOCS3 are especially important, since they can inhibit both MAPK and NF-κB pathways induced by IL-1 [12]. The objective of this study was to determine whether mechanical load affected anti-inflammatory mediators along with anti-catabolic events.
Boundary Mode Frictional Properties of Meniscal Repair Tissue
Authors: Galley Natalie K. , Gleghorn Jason P. , Wright Timothy , Doty Stephen , Maher Suzanne , Bonassar Lawrence J.
Published: March 2014

More than 1 million procedures for the total or partial removal of the meniscus are performed in the United States and Europe each year. However, it has been found that the knee can lose functionality when even small parts of the meniscus are removed, leading to degenerative changes in the joint. Healing of the medial meniscus in particular is problematic since blood vessels are present in only the outer 10–25% of the meniscus, making it desirable to preserve as much of the meniscus as possible.
Numerical Experiment of MR-Measurement-Integrated Simulation of Steady Blood Flow in a Cerebral Aneurysm
Authors: Funamoto Kenichi , Suzuki Yoshitsugu , Hayase Toshiyuki , Kosugi Takashi , Isoda Haruo
Published: March 2014

Much research has been conducted to obtain detailed and accurate information of blood flow field for clarification and advanced diagnosis of circulatory diseases. In order to reproduce complicated real flow field, we have proposed the concept of integration of measurement and computation, and developed the ultrasonic-measurement-integrated (UMI) simulation [1, 2]. In this study, we propose MR-measurement-integrated (MR-MI) simulation by applying the methodology to the MR (Magnetic Resonance) measurement. In the MR-MI simulation, the difference between the computational result and the PC MRI (Phase-Contrast Magnetic Resonance Imaging) measurement data of the three-dimensional velocity vector field is fed back to the numerical simulation (see Fig. 1). The objective in this study is to investigate the characteristics of MR-MI simulation by numerical experiment dealing with a model steady blood flow field in a cerebral aneurysm.
Extreme Elongation of Vesicles Under DC Electric Fields
Authors: Sadik Mohamed M. , Shan Jerry , Shreiber David , Lin Hao
Published: March 2014

Motive . The motivation of the current study is to investigate the response of vesicles to applied electric fields, with potential applications in electroporation-mediated molecular delivery [3]. In this technique, an applied field transiently permeabilizes the cell membrane to gain access to the cytoplasm, and deliver active agents such as genes, RNA, proteins into the cell. Although widely applied in classical and emerging areas such as drug delivery and stem cell research, current electroporation techniques suffer from low efficiency and high cell death [4]. The present work is a step towards understanding the complex fundamental processes involved in electroporation, and possibly improving it via parametric optimization. For this purpose we use vesicular cellular mimics as our model to provide good controllability, and to focus on the dynamics of the lipid membrane. Our preliminary results show extreme elongation of the vesicles under high-strength, short-duration DC pulses. Such deformation may significantly affect electroporation, and hence the efficiency of molecular delivery.
The Influence of Realistic Arteriovenous (AV) Fistula Wall Shear Stress (WSS) on Endothelial Cell (EC) Gene Expression: A Correlation to Intimal Hyperplasia Development
Authors: Carroll Gráinne T. , Devereux Paul D. , Callanan Anthony , McGloughlin Tim M. , Walsh Michael T.
Published: March 2014

The low patency rates of Arteriovenous (AV) fistulae are well documented in the literature [1]. Up to 90% of AV fistula morbidity is caused by stenotic lesion formation and the subsequent development of thrombosis in the Vascular Access (VA) junction [1]. The underlying pathology of these stenotic lesions is intimal hyperplasia (IH) which has been characterized by the degradation of the extra cellular matrix (ECM), migration and proliferation of smooth muscle cells (SMCs) and the infiltration of leukocytes and monocytes into the intima. IH primarily occurs in a number of key locations within the VA junction of AV fistulae which include the suture line of the anastomosis, on the floor of the vein opposite the VA junction and downstream of the anastomosis within the venous conduit of the AV fistula [2].
Identification and Stability Analysis of the Postural Control System During Small Magnitude Perturbations
Authors: Davidson Bradley S. , Madigan Michael L. , Southward Steve C. , Nussbaum Maury A.
Published: March 2014

Age-related increases in postural sway during quiet standing are well-documented [1]. These increases could result from age-related degradation of sensory information from the somatosensory [2] and vestibular [3] systems, or may result from inaccurate or imprecise muscle forces resulting from excitation-contraction uncoupling [4].
Evaluation of Analytic Estimates of Ventricular Wall Stress Using the Finite Element Method
Authors: Ingrassia Christopher M. , Jani Shantanu Y. , Costa Kevin D.
Published: March 2014

The importance of ventricular wall stress to cardiac function has been well-documented [1, 2], although accurate quantification remains a challenge. In this study, three popular analytic formulas for estimating circumferential wall stress were comprehensively evaluated to identify the conditions for which their use may be appropriate. In particular, the equations of Laplace [3], Mirsky [4], and Janz [5] are commonly used in the fields of cardiology and echocardiography; despite the inaccuracy of key theoretical assumptions, they have been attractive for their simplicity. For validation, we employed specialized finite element methods, developed specifically for cardiac mechanics applications [6], to compute regional wall stress in a series of model chambers having systematically varying geometric and material complexity. We limited our analysis to circumferential stress for consistency with the theoretical equations, and because of its relevance to cardiac mechanics.
Free-Standing Single-Atom-Thick Iron Membranes Suspended in Graphene Pores
Authors: Zhao Jiong , Deng Qingming , Bachmatiuk Alicja , Sandeep Gorantla , Popov Alexey , Eckert Jürgen , Rümmeli Mark H.
Published: March 2014

Iron in Graphene

Carbon or other covalently bonded materials, like boron nitride, can form two-dimensional sheets because of the strong bonding between the atoms. In contrast, metals share electrons in a three-dimensional delocalized way, and this could preclude the formation of thin stable sheets. Nevertheless,

Zhao
et al.

(p.
1228
) observed pure iron membranes suspended across the pores in a graphene sheet. This phenomenon was discovered when an iron chloride solution, used to process the graphene, decomposed to form pure iron films across the pores.
Vertebrate Limb Bud Formation Is Initiated by Localized Epithelial-to-Mesenchymal Transition
Authors: Gros Jerome , Tabin Clifford J.
Published: March 2014

Where Do You Want Your Leg?

Initiation of limb formation is the key to understanding limb-cell specification and patterning during development.
Gros and Tabin
(p.
1253
) show that a localized epithelial-to-mesenchymal transition triggers the formation of the limb. Finding that limbs initiate through cell-state change, and not through differential proliferation, redefines questions such as how limb buds are placed on the body plan.
Internal mRNA Methylation Finally Finds Functions
Authors: Nilsen Timothy W.
Published: March 2014

Methylation of internal adenosine residues in messenger RNA (mRNA) modulates mRNA metabolism in both the nucleus and cytoplasm.
Opening Doors to Engineering
Girls Coming to Tech!
A History of American Engineering Education for Women

by Amy Sue Bix

MIT Press, Cambridge, MA, 2014. 372 pp. $34, £23.95. ISBN 9780262019545. Engineering Studies.
Authors: Klawe Maria
Published: March 2014

Bix uses the examples of Georgia Tech, CalTech, and MIT to explore how women gained entrance to the traditionally male field of engineering.
Identification and Differentiation of Candida parapsilosis Complex Species by Use of Exon-Primed Intron-Crossing PCR
Authors: Feng Xiaobo , Wu Zengbin , Ling Bo , Pan Shuming , Liao Wanqing , Pan Weihua , Yao Zhirong
Published: March 2014

The
Candida parapsilosis
complex is composed of
Candida parapsilosis
sensu stricto
,
Candida orthopsilosis
,
Candida metapsilosis
, and the closely related species
Lodderomyces elongisporus
. An exon-primed intron-crossing PCR assay was developed here to distinguish the members of the species complex on the basis of the distinct sizes of amplicons, and
Candida orthopsilosis
and
Candida metapsilosis
were further discriminated by restriction enzyme analysis.
Loop-Mediated Isothermal Amplification Test for Detection of Neisseria gonorrhoeae in Urine Samples and Tolerance of the Assay to the Presence of Urea
Authors: Edwards Thomas , Burke Patricia A. , Smalley Helen B. , Gillies Liz , Hobbs Glyn
Published: March 2014

A loop-mediated isothermal amplification (LAMP) assay for open reading frame 1 (ORF1) of the glutamine synthetase gene of
Neisseria gonorrhoeae
was able to tolerate urea concentrations of ≤1.8 M, compared with a PCR assay that was functional at concentrations of <100 mM. The LAMP assay was as sensitive as the PCR assay while being faster and simpler to perform.
Improved Detection of Bacterial Central Nervous System Infections by Use of a Broad-Range PCR Assay
Authors: Meyer T. , Franke G. , Polywka S. K. A. , Lütgehetmann M. , Gbadamosi J. , Magnus T. , Aepfelbacher M.
Published: March 2014

A universal PCR assay for bacteria and fungi detected meningitis pathogens in 65% of 20 cerebrospinal fluid (CSF) samples from patients with suspected central nervous system (CNS) infections compared to a 35% detection rate by culture and/or microscopy methods. Thus, the PCR assay can improve the diagnosis rate of infective meningitis when standard methods provide a negative result.
Multilocus Sequence Typing of Mycoplasma hyorhinis Strains Identified by a Real-Time TaqMan PCR Assay
Authors: Tocqueville Véronique , Ferré Séverine , Nguyen Ngoc Hong Phuc , Kempf Isabelle , Marois-Créhan Corinne
Published: March 2014

A real-time TaqMan PCR assay based on the gene encoding the protein p37 was developed to detectMycoplasma hyorhinis. Its specificity was validated with 29 epidemiologically unrelatedM. hyorhinisstrains (28 field strains and one reference strain) and other mycoplasma species or with other microorganisms commonly found in pigs. The estimated detection limit of this qPCR assay was 125 microorganism equivalents/μl. The same 29 epidemiologically unrelatedM. hyorhinisstrains and four previously fully sequenced strains were typed by two portable typing methods, the sequencing of the p37 gene and a multilocus sequence typing (MLST) scheme. The first method revealed 18 distinct nucleotide sequences and insufficient discriminatory power (0.934). The MLST scheme was developed with the sequenced genomes of theM. hyorhinisstrains HUB-1, GDL-1, MCLD, and SK76 and based on the genesdnaA,rpoB,gyrB,gltX,adk, andgmk. In total, 2,304 bp of sequence was analyzed for each strain. MLST was capable of subdividing the 33 strains into 29 distinct sequence types. The discriminatory power of the method was >0.95, which is the threshold value for interpreting typing results with confidence (D= 0.989). Population analysis showed that recombination inM. hyorhinisoccurs and that strains are diverse but with a certain clonality (one unique clonal complex was identified). The new qPCR assay and the robust MLST scheme are available for the acquisition of new knowledge onM. hyorhinisepidemiology. A web-accessible database has been set up for theM. hyorhinisMLST scheme athttp://pubmlst.org/mhyorhinis/.
Reinitiation after Translation of Two Upstream Open Reading Frames (ORF) Governs Expression of the ORF35-37 Kaposi's Sarcoma-Associated Herpesvirus Polycistronic mRNA
Authors: Kronstad Lisa M. , Brulois Kevin F. , Jung Jae U. , Glaunsinger Britt A.
Published: March 2014

The Kaposi's sarcoma-associated herpesvirus (KSHV) ORF36 protein kinase is translated as a downstream gene from the ORF35-37 polycistronic mRNA via a unique mechanism involving short upstream open reading frames (uORFs) located in the 5′ untranslated region. Here, we confirm that ORF35-37 is functionally dicistronic during infection and demonstrate that mutation of the dominant uORF restricts KSHV replication. Leaky scanning past the uORFs facilitates ORF35 expression, while a reinitiation mechanism after translation of the uORFs enables ORF36 expression.
Kinetic and Structural Analysis of Coxsackievirus B3 Receptor Interactions and Formation of the A-Particle
Authors: Organtini Lindsey J. , Makhov Alexander M. , Conway James F. , Hafenstein Susan , Carson Steven D.
Published: March 2014

The coxsackievirus and adenovirus receptor (CAR) has been identified as the cellular receptor for group B coxsackieviruses, including serotype 3 (CVB3). CAR mediates infection by binding to CVB3 and catalyzing conformational changes in the virus that result in formation of the altered, noninfectious A-particle. Kinetic analyses show that the apparent first-order rate constant for the inactivation of CVB3 by soluble CAR (sCAR) at physiological temperatures varies nonlinearly with sCAR concentration. Cryo-electron microscopy (cryo-EM) reconstruction of the CVB3-CAR complex resulted in a 9.0-Å resolution map that was interpreted with the four available crystal structures of CAR, providing a consensus footprint for the receptor binding site. The analysis of the cryo-EM structure identifies important virus-receptor interactions that are conserved across picornavirus species. These conserved interactions map to variable antigenic sites or structurally conserved regions, suggesting a combination of evolutionary mechanisms for receptor site preservation. The CAR-catalyzed A-particle structure was solved to a 6.6-Å resolution and shows significant rearrangement of internal features and symmetric interactions with the RNA genome.

IMPORTANCE
This report presents new information about receptor use by picornaviruses and highlights the importance of attaining at least an ∼9-Å resolution for the interpretation of cryo-EM complex maps. The analysis of receptor binding elucidates two complementary mechanisms for preservation of the low-affinity (initial) interaction of the receptor and defines the kinetics of receptor-catalyzed conformational change to the A-particle.
The C-Terminal Repeat Domains of nsP3 from the Old World Alphaviruses Bind Directly to G3BP
Authors: Panas Marc D. , Ahola Tero , McInerney Gerald M.
Published: March 2014

The Old World alphaviruses block stress granule assembly by sequestration of RasGAP SH3-domain binding protein (G3BP). Here, we show that the proline-rich sequences in the hypervariable domain of nonstructural protein 3 (nsP3) of both Semliki Forest virus and Chikungunya virus were dispensable for binding to G3BP. nsP3 variants with or without this domain colocalized with G3BP. Furthermore, we show that the C-terminal repeat motifs of nsP3 were sufficient for G3BP binding.
Pseudorabies Virus pUL46 Induces Activation of ERK1/2 and Regulates Herpesvirus-Induced Nuclear Envelope Breakdown
Authors: Schulz Katharina S. , Liu XueQiao , Klupp Barbara G. , Granzow Harald , Cohen Jeffrey I. , Mettenleiter Thomas C.
Published: March 2014

Herpesvirus capsid morphogenesis occurs in the nucleus, while final maturation takes place in the cytosol, requiring translocation of capsids through the nuclear envelope. The nuclear egress complex, consisting of homologs of herpes simplex virus pUL31 and pUL34, is required for efficient nuclear egress via primary envelopment and de-envelopment. Recently, we described an alternative mode of nuclear escape by fragmentation of the nuclear envelope induced by replication-competent pUL31 and pUL34 deletion mutants of the alphaherpesvirus pseudorabies virus (PrV), which had been selected by serial passaging in cell culture. Both passaged viruses carry congruent mutations in seven genes, including
UL46
, which encodes one of the major tegument proteins. Herpesvirus pUL46 homologs have recently been shown to activate the PI3K-Akt and ERK1/2 signaling pathways, which are involved in regulation of mitosis and apoptosis. Since in uninfected cells fragmentation of the nuclear envelope occurs during mitosis and apoptosis, we analyzed whether pUL46 of PrV is involved in signaling events impairing the integrity of the nuclear envelope. We show here that PrV pUL46 is able to induce phosphorylation of ERK1/2 and, thus, expression of ERK1/2 target genes but fails to activate the PI3K-Akt pathway. Deletion of UL46 from PrV-ΔUL34Pass and PrV-ΔUL31Pass or replacement by wild-type UL46 resulted in enhanced nuclear envelope breakdown, indicating that the mutations in pUL46 may limit the extent of NEBD. Thus, although pUL46 induces ERK1/2 phosphorylation, controlling the integrity of the nuclear envelope is independent of the ERK1/2 signaling pathway.

IMPORTANCE
Herpesvirus nucleocapsids can leave the nucleus by regulated, vesicle-mediated transport through the nuclear envelope, designated nuclear egress, or by inducing nuclear envelope breakdown (NEBD). The viral proteins involved in NEBD are unknown. We show here that the pseudorabies virus tegument protein pUL46 induces the ERK1/2 signaling pathway and modulates NEBD. However, these two processes are independent and ERK1/2 signaling induced by pUL46 is not involved in herpesvirus-induced NEBD.
Mucosal Immunization with a Candidate Universal Influenza Vaccine Reduces Virus Transmission in a Mouse Model
Authors: Price Graeme E. , Lo Chia-Yun , Misplon Julia A. , Epstein Suzanne L.
Published: March 2014

Pandemic influenza is a major public health concern, but conventional strain-matched vaccines are unavailable early in a pandemic. Candidate “universal” vaccines targeting the viral antigens nucleoprotein (NP) and matrix 2 (M2), which are conserved among all influenza A virus strains and subtypes, could be manufactured in advance for use at the onset of a pandemic. These vaccines do not prevent infection but can reduce disease severity, deaths, and virus titers in the respiratory tract. We hypothesized that such immunization may reduce virus transmission from vaccinated, infected animals. To investigate this hypothesis, we studied mouse models for direct-contact and airborne transmission of H1N1 and H3N2 influenza viruses. We established conditions under which virus transmission occurs and showed that transmission efficiency is determined in part at the level of host susceptibility to infection. Our findings indicate that virus transmission between mice has both airborne and direct-contact components. Finally, we demonstrated that immunization with recombinant adenovirus vectors expressing NP and M2 significantly reduced the transmission of virus to cohoused, unimmunized mice in comparison to controls. These findings have broad implications for the impact of conserved-antigen vaccines, not only in protecting the vaccinated individual but also in protecting others by limiting influenza virus transmission and potentially reducing the size of epidemics.

IMPORTANCE
Using a mouse model of influenza A virus transmission, we demonstrate that a candidate “universal” influenza vaccine both protects vaccinated animals from lethal infection and reduces the transmission of virus from vaccinated to nonvaccinated mice. This vaccine induces immunity against proteins conserved among all known influenza A virus strains and subtypes, so it could be used early in a pandemic before conventional strain-matched vaccines are available and could potentially reduce the spread of infection in the community.
An Important Role for Mitochondrial Antiviral Signaling Protein in the Kaposi's Sarcoma-Associated Herpesvirus Life Cycle
Authors: West John A. , Wicks Megan , Gregory Sean M. , Chugh Pauline , Jacobs Sarah R. , Zhang Zhigang , Host Kurtis M. , Dittmer Dirk P. , Damania Blossom
Published: March 2014

Kaposi's sarcoma-associated herpesvirus (KSHV) has been shown to be recognized by two families of pattern recognition receptors (PRRs), Toll-like receptors (TLRs) and NOD-like receptors (NLRs). Here we show that MAVS and RIG-I (retinoic acid-inducible gene 1), an RLR family member, also have a role in suppressing KSHV replication and production. In the context of primary infection, we show that in cells with depleted levels of MAVS or RIG-I, KSHV transcription is increased, while beta interferon (IFN-β) induction is attenuated. We also observed that MAVS and RIG-I are critical during the process of reactivation. Depletion of MAVS and RIG-I prior to reactivation led to increased viral load and production of infectious virus. Finally, MAVS depletion in latent KSHV-infected B cells leads to increased viral gene transcription. Overall, this study suggests a role for MAVS and RIG-I signaling during different stages of the KSHV life cycle.

IMPORTANCE
We show that RIG-I and its adaptor protein, MAVS, can sense KSHV infection and that these proteins can suppress KSHV replication following primary infection and/or viral reactivation.
An Immature Retroviral RNA Genome Resembles a Kinetically Trapped Intermediate State
Authors: Grohman Jacob K. , Gorelick Robert J. , Kottegoda Sumith , Allbritton Nancy L. , Rein Alan , Weeks Kevin M.
Published: March 2014

Retroviral virions initially assemble in an immature form that differs from that of the mature infectious particle. The RNA genomes in both immature and infectious particles are dimers, and interactions between the RNA dimer and the viral Gag protein ensure selective packaging into nascent immature virions. We used high-sensitivity selective 2′-hydroxyl acylation analyzed by primer extension (SHAPE) to obtain nucleotide-resolution structural information from scarce, femtomole quantities of Moloney murine leukemia virus (MuLV) RNA inside authentic virions and from viral RNA extracted from immature (protease-minus) virions. Our secondary structure model of the dimerization and packaging domain indicated that a stable intermolecular duplex known as PAL2, previously shown to be present in mature infectious MuLV particles, was sequestered in an alternate stem-loop structure inside immature virions. The intermediate state corresponded closely to a late-folding intermediate that we detected in time-resolved studies of the free MuLV RNA, suggesting that the immature RNA structure reflects trapping of the intermediate folding state by interactions in the immature virion. We propose models for the RNA-protein interactions that trap the RNA in the immature state and for the conformational rearrangement that occurs during maturation of virion particles.

IMPORTANCE
The structure of the RNA genome in mature retroviruses has been studied extensively, whereas very little was known about the RNA structure in immature virions. The immature RNA structure is important because it is the form initially selected for packaging in new virions and may have other roles. This lack of information was due to the difficulty of isolating sufficient viral RNA for study. In this work, we apply a high-sensitivity and nucleotide-resolution approach to examine the structure of the dimerization and packaging domain of Moloney murine leukemia virus. We find that the genomic RNA is packaged in a high-energy state, suggesting that interactions within the virion hold or capture the RNA before it reaches its most stable state. This new structural information makes it possible to propose models for the conformational changes in the RNA genome that accompany retroviral maturation.
Cell Surface Vimentin Is an Attachment Receptor for Enterovirus 71
Authors: Du Ning , Cong Haolong , Tian Hongchao , Zhang Hua , Zhang Wenliang , Song Lei , Tien Po
Published: March 2014

Enterovirus 71 (EV71) is a highly transmissible pathogenic agent that causes severe central nervous system diseases in infected infants and young children. Here, we reported that EV71 VP1 protein could bind to vimentin intermediate filaments expressed on the host cell surface. Soluble vimentin or an antibody against vimentin could inhibit the binding of EV71 to host cells. Accompanied with the reduction of vimentin expression on the cell surface, the binding of EV71 to cells was remarkably decreased. Further evidence showed that the N terminus of vimentin is responsible for the interaction between EV71 and vimentin. These results indicated that vimentin on the host cell surface may serve as an attachment site that mediated the initial binding and subsequently increased the infectivity of EV71.

IMPORTANCEThis study delivers important findings on the roles of vimentin filaments in relation to EV71 infection and provides information that not only improves our understanding of EV71 pathogenesis but also presents us with potentially new strategies for the treatment of diseases caused by EV71 infections.
Neisseria meningitidisas a cause of facial cellulitis
Authors: Ozaki Brent , Kittai Adam , Chang Suzanne
Published: March 2014

A 68-year-old man presented with facial cellulitis and found to haveNeisseria meningitidisbacteraemia with no evidence of infection outside of the facial soft tissue. He was treated with a course of intravenous ceftriaxone and transitioned to oral amoxicillin on discharge with significant improvement of his symptoms.N meningitidisis best recognised as a causal agent of bacterial meningitis. To our knowledgeN meningitidiscellulitis has only been described in 12 other cases. In this case series we describe and summarise our case, along with the 12 cases already reported in the literature. We report this case series to highlight the importance of recognisingN meningitidisin the differential in patients presenting with acute skin and soft tissue infections especially involving the periorbital, head and neck regions.
An exploratory trial implementing a community-based child oral health promotion intervention for Australian families from refugee and migrant backgrounds: a protocol paper for Teeth Tales
Authors: Gibbs Lisa , Waters Elizabeth , de Silva Andrea , Riggs Elisha , Moore Laurence , Armit Christine , Johnson Britt , Morris Michal , Calache Hanny , Gussy Mark , Young Dana , Tadic Maryanne , Christian Bradley , Gondal Iqbal , Watt Richard , Pradel Veronika , Truong Mandy , Gold Lisa
Published: March 2014

Introduction

Inequalities are evident in early childhood caries rates with the socially disadvantaged experiencing greater burden of disease. This study builds on formative qualitative research, conducted in the Moreland/Hume local government areas of Melbourne, Victoria 2006–2009, in response to community concerns for oral health of children from refugee and migrant backgrounds. Development of the community-based intervention described here extends the partnership approach to cogeneration of contemporary evidence with continued and meaningful involvement of investigators, community, cultural and government partners. This trial aims to establish a model for child oral health promotion for culturally diverse communities in Australia.

Methods and analysis

This is an exploratory trial implementing a community-based child oral health promotion intervention for Australian families from refugee and migrant backgrounds. Families from an Iraqi, Lebanese or Pakistani background with children aged 1–4 years, residing in metropolitan Melbourne, were invited to participate in the trial by peer educators from their respective communities using snowball and purposive sampling techniques. Target sample size was 600. Moreland, a culturally diverse, inner-urban metropolitan area of Melbourne, was chosen as the intervention site. The intervention comprised peer educator led community oral health education sessions and reorienting of dental health and family services through cultural Competency Organisational Review (CORe).

Ethics and dissemination

Ethics approval for this trial was granted by the University of Melbourne Human Research Ethics Committee and the Department of Education and Early Childhood Development Research Committee. Study progress and output will be disseminated via periodic newsletters, peer-reviewed research papers, reports, community seminars and at National and International conferences.

Trial registration number

Australian New Zealand Clinical Trials Registry (ACTRN12611000532909).
Using physician-linked mailed invitations in an organised colorectal cancer screening programme: effectiveness and factors associated with response
Authors: Tinmouth Jill , Baxter Nancy N , Paszat Lawrence F , Rabeneck Linda , Sutradhar Rinku , Yun Lingsong
Published: March 2014

Objectives

A central tenet of organised cancer screening is that all persons in a target population are invited. The aims of this study were to identify participant and physician factors associated with response to mailed physician-linked invitations (study 1) and to evaluate their effectiveness in an organised colorectal cancer (CRC) screening programme (study 2).

Design and setting

2 studies (study 1—cohort design and study 2—matched cohort design, comprising study 1 participants and a matched control group) were conducted in the context of Ontario's organised province-wide CRC screening programme.

Participants

102 family physicians and 11 302 associated eligible patients from a technical evaluation (‘the Pilot’) of large-scale mailed invitations for CRC screening were included. Matched controls were randomly selected using propensity scores from among eligible patients associated with family physicians in similar practice types as the Pilot physicians.

Intervention

Physician-linked mailed invitation to have CRC screening.

Outcomes

Uptake of faecal occult blood test (FOBT) within 6 months of mailed invitation (primary) and uptake of FOBT or colonoscopy within 6 months of mailed invitation (secondary).

Results

Factors significantly associated with uptake of FOBT included prior FOBT use, older participant age, greater participant comorbidity and having a female physician. In the matched analysis, Pilot participants were more likely to complete an FOBT (22% vs 8%, p<0.0001) or an FOBT or colonoscopy (25% vs 11%, p<0.0001) within 6 months of mailed invitation than matched controls. The number needed to invite to screen one additional person was 7.

Conclusions

Centralised large-scale mailing of physician-linked invitations is feasible and effective in the context of organised CRC screening.
Evaluation of corneal anaesthesia after the application of topical 2 per cent lidocaine, 0.5 per cent bupivacaine and 1 per cent ropivacaine in dogs
Authors: Costa D. , Peña M. T. , Ríos J. , Leiva M.
Published: March 2014

The objective of this study was to describe and compare the efficacy and duration of topical anaesthesia induced by 2 per cent lidocaine (L), 0.5 per cent bupivacaine (B) and 1 per cent ropivacaine (R) in the dog using 24 clinically healthy beagles with normal ocular examination. Dogs were randomly divided into three groups: 2 per cent lidocaine (n=8), 0.5 per cent bupivacaine (n=8) and 1 per cent ropivacaine (n=8). The baseline corneal touch threshold (CTT) was measured using a Cochet‐Bonnet aesthesiometer. Following baseline CTT measurement, a single drop of the assigned anaesthetic was applied to each eye and the CTT was measured bilaterally within one minute after administration and every five minutes until the basal CTT value was restored. Data were analysed with non‐parametric analysis of variance models and Dunnet's test for post hoc analysis. One per cent ropivacaine was the most effective drug (LCTTmax =3 cm, BCTTmax =2 cm, RCTTmax =0 cm; P<0.001), and had the shortest latency (LLatency =5 minutes, BLatency =5 minutes, RLatency =1 minute; P<0.001) and the smallest AUC (LAUC =80 cm×minute, BAUC =68.25 cm×minute, RAUC =36.88 cm×minute; P<0.001). There was no statistical difference in the duration of corneal anaesthesia between the groups (P=0.09) and all topical anaesthetics tested reduced corneal sensitivity, although 1 per cent ropivacaine had the maximal and quickest anaesthetic effect. This drug could be used for specific diagnostic procedures where quick and short, but effective, corneal anaesthesia is needed.