bluuebunny/crossref_metadata_2025 huggingface dataset:
Zinc Binding Activity of Human Metapneumovirus M2-1 Protein Is Indispensable for Viral Replication and Pathogenesis
In Vivo
Authors: Cai Hui , Zhang Yu , Ma Yuanmei , Sun Jing , Liang Xueya , Li Jianrong
Published: April 2015

Human metapneumovirus (hMPV) is a member of the
Pneumovirinae
subfamily in the
Paramyxoviridae
family that causes respiratory tract infections in humans. Unlike members of the
Paramyxovirinae
subfamily, the polymerase complex of pneumoviruses requires an additional cofactor, the M2-1 protein, which functions as a transcriptional antitermination factor. The M2-1 protein was found to incorporate zinc ions, although the specific role(s) of the zinc binding activity in viral replication and pathogenesis remains unknown. In this study, we found that the third cysteine (C21) and the last histidine (H25) in the zinc binding motif (CCCH) of hMPV M2-1 were essential for zinc binding activity, whereas the first two cysteines (C7 and C15) play only minor or redundant roles in zinc binding. In addition, the zinc binding motif is essential for the oligomerization of M2-1. Subsequently, recombinant hMPVs (rhMPVs) carrying mutations in the zinc binding motif were recovered. Interestingly, rhMPV-C21S and -H25L mutants, which lacked zinc binding activity, had delayed replication in cell culture and were highly attenuated in cotton rats. In contrast, rhMPV-C7S and -C15S strains, which retained 60% of the zinc binding activity, replicated as efficiently as rhMPV in cotton rats. Importantly, rhMPVs that lacked zinc binding activity triggered high levels of neutralizing antibody and provided complete protection against challenge with rhMPV. Taken together, these results demonstrate that zinc binding activity is indispensable for viral replication and pathogenesis
in vivo
. These results also suggest that inhibition of zinc binding activity may serve as a novel approach to rationally attenuate hMPV and perhaps other pneumoviruses for vaccine purposes.

IMPORTANCE
The pneumoviruses include many important human and animal pathogens, such as human respiratory syncytial virus (hRSV), hMPV, bovine RSV, and avian metapneumovirus (aMPV). Among these viruses, hRSV and hMPV are the leading causes of acute respiratory tract infection in infants and children. Despite major efforts, there is no antiviral or vaccine to combat these diseases. All known pneumoviruses encode a zinc binding protein, M2-1, which is a transcriptional antitermination factor. In this work, we found that the zinc binding activity of M2-1 is essential for virus replication and pathogenesis
in vivo
. Recombinant hMPVs that lacked zinc binding activity were not only defective in replication in the upper and lower respiratory tract but also triggered a strong protective immunity in cotton rats. Thus, inhibition of M2-1 zinc binding activity can lead to the development of novel, live attenuated vaccines, as well as antiviral drugs for pneumoviruses.
Autotransplantation for the management of ketamine ureteritis
Authors: Raison Nicholas Tobias Johannes , O'Brien Timothy , Game David , Olsburgh Jonathon
Published: April 2015

Ketamine-associated cystitis is a well-recognised syndrome; yet upper urinary tract involvement remains poorly understood. We present the case of a 33-year-old man who developed ketamine-associated cystitis and ureteritis. The patient's severe bladder symptoms required subtotal cystectomy and orthotopic reconstruction. However, the associated ureteritis led to bilateral ureteric obstruction and renal failure. Bilateral autotransplantation with pyelovesicostomy was performed. This first case of autotransplantation for ketamine uropathy helps to demonstrate the potentially devastating effects of ketamine on the urinary tract.
Severe thrombocytopenia and recurrent epistaxis associated with primary Epstein-Barr virus infection
Authors: Tilden William , Valliani Shahnawaz
Published: April 2015

Infectious mononucleosis, caused by the Epstein-Barr virus (EBV), generally follows a benign, yet protracted course, with the majority of symptoms being systemic somatic symptoms. Rarely, the clinical picture can be complicated by more acute severe haemotological sequelae of the disease, requiring hospitalisation and causing diagnostic uncertainty, particularly when distinguishing between a viral illness and a lymphoproliferative disorder. We describe the case of a young male patient who presented with headache, recurrent epistaxis and severe thrombocytopenia.
Granulomatous interstitial pneumonia induced by the intake of rice bran pickles: a rare subtype of pulmonary manifestation associated with food allergy
Authors: Kinoshita Yoshiaki , Sakamoto Atsuhiko , Aishima Shinichi , Hidaka Kouko
Published: April 2015

Pulmonary manifestations associated with food allergy are rich in variety. We report the first case of food-induced granulomatous interstitial pneumonia mimicking hypersensitivity pneumonitis (HP). A 77-year-old woman with respiratory symptoms was referred to our hospital. We performed a surgical lung biopsy, which showed the features of granulomatous interstitial pneumonia. Her clinical history resembled those observed in HP. However, avoidance of exposure to the causative antigens did not improve her symptoms. Moreover, the patient had some features inconsistent with HP, such as elevated serum IgE levels, blood eosinophilia, intrathoracic lymphadenopathies and pleural effusion. Therefore, we pursued another extrinsic non-inhaled antigen as the cause of pulmonary involvements. We noted that she had been eating homemade rice bran pickles, and pulmonary involvements were induced by an ingestion challenge test. We suggest that granulomatous interstitial pneumonia may be a rare subtype of the pulmonary manifestations associated with food allergy.
Delayed diagnosis of angiosarcoma of the spleen: clinically presenting as recurrent haemoperitoneum following embolisation
Authors: Kornmann Verena , van Rijn Philip , Mulder Dries , Reijnders Koen
Published: April 2015

Angiosarcoma is a highly aggressive and extremely rare neoplasm of the spleen, with a limited number of reported cases worldwide.

We report a case of a 69-year-old man who presented with progressive symptoms of fatigue, abdominal and back pain, anaemia and haemoperitoneum 1 year following embolisation of the spleen for splenic rupture. Additional imaging and colonoscopy with biopsy revealed intra-abdominal fluid and a colonic adenocarcinoma. Diagnostic laparoscopy demonstrated a haemoperitoneum and colon carcinoma, after which splenectomy via laparotomy was performed. Pathology report revealed an angiosarcoma of the spleen with peritoneal tumour deposits.

Rupturing of a spleen may be due to an underlying disease. Therefore, the differential diagnosis of splenic rupture should include the possibility of a splenic tumour. The definitive diagnosis and treatment of a splenic angiosarcoma may require splenectomy, although prognosis is poor.
Variability in the international normalised ratio (INR) in patients with antiphospholipid syndrome and positive lupus anticoagulant: should the INR targets be higher?
Authors: Baquero-Salamanca Marielena , Téllez-Arévalo Angélica María , Calderon-Ospina Carlos
Published: April 2015

We present the case of a 34-year-old woman with a history of antiphospholipid syndrome with triple positivity for antiphospholipid antibodies, who had multiple thrombotic events, predominantly pulmonary embolic events, despite treatment with enoxaparin. She is currently on warfarin, with which she has been adequately controlled most of the time, presenting with only one haemorrhagic event consisting of haematuria and prolonged international normalised ratio (INR) without bleeding. This kind of patient represents a challenge for clinicians, particularly due to INR therapeutic targets, which should be higher than recommended in other patients due to the lupus anticoagulant positivity.
Pituitary apoplexy presenting with anorexia and hyponatraemia
Authors: Sasaki Yosuke , Nakata Kenji , Suzuki Kenichi , Ando Yasuyo
Published: April 2015

Pituitary apoplexy, a syndrome caused by haemorrhage into the pituitary gland, typically manifests as sudden severe headache, visual symptoms and hypopituitarism, including adrenal insufficiency. We report a case of a 65-year-old man with adrenal insufficiency due to pituitary apoplexy presenting with anorexia following temporal headache and diagnosed through evaluation for hyponatraemia. MRI focusing on the pituitary gland helped to confirm the diagnosis. Our experience serves as a useful reminder of this atypical presentation of pituitary apoplexy, also known as ‘subclinical pituitary apoplexy,’ and underscores the importance of careful evaluation for hyponatraemia using serial urine osmolality, which is useful to distinguish hypovolaemic hyponatraemia from euvolaemic hyponatraemia. Clinicians should consider pituitary apoplexy as a differential diagnosis in cases of anorexia, loss of energy or hyponatraemia, following headache even when the patient is lacking classical symptoms such as severe headache or visual symptoms.
Pregnancy in a patient with Schwachman-Diamond syndrome
Authors: Cordell Victoria , Osoba Leke
Published: April 2015

We present the case of a 26-year-old Caucasian woman with Schwachman-Diamond syndrome with regard to her obstetric and gynaecology requirements, and in particular to her antenatal care across two pregnancies.
Clinical decision-making of cardiologists regarding admission and treatment of patients with suspected unstable angina or non-ST-elevation myocardial infarction: protocol of a clinical vignette study
Authors: Engel Josien , van der Wulp Ineke , Poldervaart Judith M , Reitsma Johannes B , de Bruijne Martine C , Wagner Cordula
Published: April 2015

Introduction

Cardiologists face the difficult task of rapidly distinguishing cardiac-related chest pain from other conditions, and to thoroughly consider whether invasive diagnostic procedures or treatments are indicated. The use of cardiac risk-scoring instruments has been recommended in international cardiac guidelines. However, it is unknown to what degree cardiac risk scores and other clinical information influence cardiologists’ decision-making. This paper describes the development of a binary choice experiment using realistic descriptions of clinical cases. The study aims to determine the importance cardiologists put on different types of clinical information, including cardiac risk scores, when deciding on the management of patients with suspected unstable angina or non-ST-elevation myocardial infarction.

Methods and analysis

Cardiologists were asked, in a nationwide survey, to weigh different clinical factors in decision-making regarding patient admission and treatment using realistic descriptions of patients in which specific characteristics are varied in a systematic way (eg, web-based clinical vignettes). These vignettes represent patients with suspected unstable angina or non-ST-elevation myocardial infarction. Associations between several clinical characteristics, with cardiologists’ management decisions, will be analysed using generalised linear mixed models.

Ethics and dissemination

The study has received ethics approval and informed consent will be obtained from all participating cardiologists. The results of the study will provide insight into the relative importance of cardiac risk scores and other clinical information in cardiac decision-making. Further, the results indicate cardiologists’ adherence to the European Society of Cardiology guideline recommendations. In addition, the detailed description of the method of vignette development applied in this study could assist other researchers or clinicians in creating future choice experiments.
Respondent-driven sampling to assess mental health outcomes, stigma and acceptance among women raising children born from sexual violence-related pregnancies in eastern Democratic Republic of Congo
Authors: Scott Jennifer , Rouhani Shada , Greiner Ashley , Albutt Katherine , Kuwert Philipp , Hacker Michele R , VanRooyen Michael , Bartels Susan
Published: April 2015

Objectives

Assess mental health outcomes among women raising children from sexual violence-related pregnancies (SVRPs) in eastern Democratic Republic of Congo and stigma toward and acceptance of women and their children.

Design

Participants were recruited using respondent-driven sampling.

Setting

Bukavu, Democratic Republic of Congo in 2012.

Participants

757 adult women raising children from SVRPs were interviewed. A woman aged 18 and older was eligible for the study if she self-identified as a sexual violence survivor since the start of the conflict (∼1996), conceived an SVRP, delivered a liveborn child and was currently raising the child. A woman was ineligible for the study if the SVRP ended with a spontaneous abortion or fetal demise or the child was not currently living or in the care of the biological mother.

Intervention

Trained female Congolese interviewers verbally administered a quantitative survey after obtaining verbal informed consent.

Outcome measures

Symptom criteria for major depressive disorder, post-traumatic stress disorder, anxiety and suicidality were assessed, as well as stigma toward the woman and her child. Acceptance of the woman and child from the spouse, family and community were analysed.

Results

48.6% met symptom criteria for major depressive disorder, 57.9% for post-traumatic stress disorder, 43.3% for anxiety and 34.2% reported suicidality. Women who reported stigma from the community (38.4%) or who reported stigma toward the child from the spouse (42.9%), family (31.8%) or community (38.1%) were significantly more likely to meet symptom criteria for most mental health disorders. Although not statistically significant, participants who reported acceptance and acceptance of their children from the spouse, family and community were less likely to meet symptom criteria.

Conclusions

Women raising children from SVRPs experience symptoms of mental health disorders. Programming addressing stigma and acceptance following sexual violence may improve mental health outcomes in this population.
A cost-benefit analysis of twice-daily consultant ward rounds and clinical input on investigation and pharmacy costs in a major teaching hospital in the UK
Authors: Ahmad Aftab , Weston Philip J , Ahmad Mahin , Sharma Dushyant , Purewal Tejpal
Published: April 2015

Objectives

Misuse of investigations, medications and hospital beds is costing the National Health Service (NHS) billions of pounds with little evidence that approaches centred on reducing overuse are sustainable. Our previous study demonstrated that twice-daily consultant ward rounds reduce inpatient length of stay and suggested a reduction in overuse of investigations and medications. This study aims to assess the impact of daily consultant ward rounds on the use of investigations and medications and estimate the potential cost benefit.

Settings

The study was performed on two medical wards in a major city university teaching hospital in Liverpool, UK, receiving acute admissions from medical assessment and emergency departments.

Participants and intervention

The total number of patients admitted, investigations performed and pharmacy costs incurred were collected for 2 years before and following a change in the working practice of consultants from twice-weekly to twice-daily consultant ward rounds on the two medical wards.

Outcome measures

We performed a cost-benefit analysis to assess the net amount of money saved by reducing inappropriate investigations and pharmacy drug use following the intervention.

Results

Despite a 70% increase in patient throughput (p<0.01) the investigations and pharmacy, costs per patient reduced by 50% over a 12-month period (p<0.01) and were sustained for the next 12 months. The reduction in investigations and medication use did not have any effect on the readmission or mortality rate (p=NS), whereas, the length of stay was almost halved (p<0.01). Daily senior clinician input resulted in a net cost saving of £336 528 per year following the intervention.

Conclusions

Daily consultant input has a significant impact on reducing the inappropriate use of investigations and pharmacy costs saving the NHS more than £650K on the two wards over a 2-year period.
CareTrack Kids—part 3. Adverse events in children's healthcare in Australia: study protocol for a retrospective medical record review
Authors: Hibbert Peter D , Hallahan Andrew R , Muething Stephen E , Lachman Peter , Hooper Tamara D , Wiles Louise K , Jaffe Adam , White Les , Wheaton Gavin R , Runciman William B , Dalton Sarah , Williams Helena M , Braithwaite Jeffrey
Published: April 2015

Introduction

A high-quality health system should deliver care that is free from harm. Few large-scale studies of adverse events have been undertaken in children's healthcare internationally, and none in Australia. The aim of this study is to measure the frequency and types of adverse events encountered in Australian paediatric care in a range of healthcare settings.

Methods and analysis

A form of retrospective medical record review, the Institute of Healthcare Improvement's Global Trigger Tool, will be modified to collect data. Records of children aged <16 years managed during 2012 and 2013 will be reviewed. We aim to review 6000–8000 records from a sample of healthcare practices (hospitals, general practices and specialists).

Ethics and dissemination

Human Research Ethics Committee approvals have been received from the Sydney Children's Hospital Network, Children's Health Queensland Hospital and Health Service, and the Women's and Children's Hospital Network in South Australia. An application is under review with the Royal Australian College of General Practitioners. The authors will submit the results of the study to relevant journals and undertake national and international oral presentations to researchers, clinicians and policymakers.
The PRONE score: an algorithm for predicting doctors’ risks of formal patient complaints using routinely collected administrative data
Authors: Spittal Matthew J , Bismark Marie M , Studdert David M
Published: April 2015

Background

Medicolegal agencies—such as malpractice insurers, medical boards and complaints bodies—are mostly passive regulators; they react to episodes of substandard care, rather than intervening to prevent them. At least part of the explanation for this reactive role lies in the widely recognised difficulty of making robust predictions about medicolegal risk at the individual clinician level. We aimed to develop a simple, reliable scoring system for predicting Australian doctors’ risks of becoming the subject of repeated patient complaints.

Methods

Using routinely collected administrative data, we constructed a national sample of 13 849 formal complaints against 8424 doctors. The complaints were lodged by patients with state health service commissions in Australia over a 12-year period. We used multivariate logistic regression analysis to identify predictors of subsequent complaints, defined as another complaint occurring within 2 years of an index complaint. Model estimates were then used to derive a simple predictive algorithm, designed for application at the doctor level.

Results

The PRONE (Predicted Risk Of New Event) score is a 22-point scoring system that indicates a doctor's future complaint risk based on four variables: a doctor's specialty and sex, the number of previous complaints and the time since the last complaint. The PRONE score performed well in predicting subsequent complaints, exhibiting strong validity and reliability and reasonable goodness of fit (c-statistic=0.70).

Conclusions

The PRONE score appears to be a valid method for assessing individual doctors’ risks of attracting recurrent complaints. Regulators could harness such information to target quality improvement interventions, and prevent substandard care and patient dissatisfaction. The approach we describe should be replicable in other agencies that handle large numbers of patient complaints or malpractice claims.
The role of biological markers of epithelial to mesenchymal transition in oesophageal adenocarcinoma, an immunohistochemical study
Authors: Prins M J D , Ruurda J P , Lolkema M P , Sitarz R , ten Kate F J W , van Hillegersberg R
Published: April 2015

Background

E-cadherin, β-catenin, epidermal growth factor receptor (EGFR), neuronal cadherin (N-cadherin) and Cyclin D1 are involved in epithelial to mesenchymal transition (EMT). However, the prognostic significance of EMT markers in oesophageal adenocarcinoma (OAC) is unknown. Aim of this study was to evaluate the prognostic value of, and the association between different EMT markers in OAC.

Methods

Tumour cores of 154 patients with OAC were included in a tissue microarray. Scoring criteria was based on immunohistochemical staining intensity.

Results

EMT-associated markers were expressed in OAC: reduced membranous E-cadherin and β-catenin were seen in 11.4% and 51.7%, nuclear β-catenin in 19.1% and EGFR and Cyclin D1 overexpression in 56.5% and 27.4% of tumours. Mesenchymal marker N-cadherin was not expressed in OAC. A positive correlation was seen between membranous β-catenin and E-cadherin expression (R=0.209, p=0.001) and between EGFR and Cyclin D1 (R=0.257, p=0.002). In univariate analysis, EGFR overexpression and membranous β-catenin staining were significantly associated with a poor survival (HR 2.145; 95% CI 1.429 to 3.218, p<0.001 and HR 1.665; 95% CI 1.114 to 2.488; p=0.013). However, Cyclin D1 (HR 1.092; 95% CI 0.702 to 1.698; p=0.697), nuclear β-catenin (HR 1.322; 95% CI 0.799 to 2.189; p=0.277) and E-cadherin (HR 1.012; 95% CI 0.554 to 1.851; p=0.968) were not associated with survival. In multivariate analysis, EGFR overexpression was an independent prognostic factor for poor survival (HR 1.678; 95% CI 1.055 to 2.668; p=0.029) together with T stage (HR 2.759; 95% CI 1.356 to 5.576; p=0.005).

Conclusions

This study supports the presence of EMT in OAC. Moreover, EGFR overexpression was independently associated with a poor survival.
Folic acid in pregnancy and mortality from cancer and cardiovascular disease: further follow-up of the Aberdeen folic acid supplementation trial
Authors: Taylor Caroline M , Atkinson Charlotte , Penfold Chris , Bhattacharya Sohinee , Campbell Doris , Davey Smith George , Leary Sam , Ness Andy
Published: April 2015

Background

Supplemental periconceptional folic acid is recommended to reduce the risk of fetal neural tube defects. A previous report indicated an elevated risk of breast cancer and all cancer deaths in later life among women randomised by alternate allocation to high-dose (5 mg/day) folic acid in pregnancy compared with placebo; however, findings were based on small numbers of cases. Our aim was to extend the previous analysis by including data from an additional 10 years of follow-up.

Methods

Records of participants in a large (n=2928) trial of folate supplementation (5 or 0.2 mg folic acid, or placebo) in pregnancy in the 1960s were linked to central registries in Scotland. Unadjusted and adjusted HRs were calculated for all-cause, cardiovascular, all cancer and breast cancer mortality, and all cancer and breast cancer morbidity. Analyses were done using (1) data from the time of the previous linkage (2002) to March 2013; and (2) data from 1980 to March 2013.

Results

There was no evidence to suggest an excess risk of morbidity or mortality in either supplementation group compared with placebo for 2002–2013 and no associations were seen for the full time period (1980–2013).

Conclusions

Findings from this extended follow-up do not support our previous observation of an elevated risk of mortality from breast cancer or all cancers in later life among women who had taken 5 mg folic acid/day during pregnancy. Furthermore, there were no associations with risk of mortality from all-causes, all cancers or cardiovascular disease.
Post-abortion initiation of long-acting reversible contraception in New Zealand
Authors: Rose Sally B , Garrett Susan M
Published: April 2015

Background

Post-abortion initiation of long-acting reversible contraception (LARC) reduces subsequent abortion rates within 24 months, but the prevalence of post-abortion LARC use in New Zealand is unknown.

Aim

To describe post-abortion initiation of intrauterine and implantable LARC methods in New Zealand between 2007 and 2012, and to determine what impact the introduction of government-funded (free) levonorgestrel (LNG) implants in August 2010 had on overall LARC use.

Design and setting

Retrospective observational study involving New Zealand abortion clinic data.

Methods

Nationally collated data on post-abortion LARC insertions were obtained for the period 2007–2012, and individual-level discharge data for patients attending a large urban hospital abortion clinic were analysed using descriptive statistics to describe annual uptake rates, and the demographic profile of LARC users during this period. Logistic regression analyses examined whether LARC use differed by parity and/or age over time.

Results

Post-abortion LARC use increased from 20.2% in 2007 to 45.6% in 2012. Intrauterine device use increased from 20.2% to 31.8% during this period, with implants contributing a further 14% to the overall use of LARC methods by 2012. Clinic data showed that LARC use increased among most demographic subgroups between 2009 and 2012, with the greatest increase among nulliparous under-20-year-olds (from 17.2% to 42.0%).

Conclusions

Post-abortion LARC use has been steadily increasing in New Zealand since 2007. Overall LARC use significantly increased following the introduction of government-funded implants, particularly among young and nulliparous women. Improving access to alternative methods of LARC may further increase uptake and reduce unwanted pregnancy rates.
The effects of adding single-joint exercises to a multi-joint exercise resistance training program on upper body muscle strength and size in trained men
Authors: de França Henrique Silvestre , Branco Paulo Alexandre Nordeste , Guedes Junior Dilmar Pinto , Gentil Paulo , Steele James , Teixeira Cauê Vazquez La Scala
Published: April 2015

The aim of this study was compare changes in upper body muscle strength and size in trained men performing resistance training (RT) programs involving multi-joint plus single-joint (MJ+SJ) or only multi-joint (MJ) exercises. Twenty young men with at least 2 years of experience in RT were randomized in 2 groups: MJ+SJ (n = 10; age, 27.7 ± 6.6 years) and MJ (n = 10; age, 29.4 ± 4.6 years). Both groups trained for 8 weeks following a linear periodization model. Measures of elbow flexors and extensors 1-repetition maximum (1RM), flexed arm circumference (FAC), and arm muscle circumference (AMC) were taken pre- and post-training period. Both groups significantly increased 1RM for elbow flexion (4.99% and 6.42% for MJ and MJ+SJ, respectively), extension (10.60% vs 9.79%, for MJ and MJ+SJ, respectively), FAC (1.72% vs 1.45%, for MJ and MJ+SJ, respectively), and AMC (1.33% vs 3.17% for MJ and MJ+SJ, respectively). Comparison between groups revealed no significant difference in any variable. In conclusion, 8 weeks of RT involving MJ or MJ+SJ resulted in similar alterations in muscle strength and size in trained participants. Therefore, the addition of SJ exercises to a RT program involving MJ exercises does not seem to promote additional benefits to trained men, suggesting MJ-only RT to be a time-efficient approach.
Linking the availability of cached food to climate change: an experimental test of the hoard-rot hypothesis
Authors: Sechley Talia H. , Strickland Dan , Norris D. Ryan
Published: April 2015

Understanding how long-term changes in climate influence populations requires knowledge of the mechanisms by which climate influences individual success and population abundance. We explored the implications of warmer falls and winters on a nonmigratory, food-caching bird, the Gray Jay (Perisoreus canadensis (L., 1766)), in Algonquin Park, Ontario, by experimentally examining the influence of temperature on the caloric content and mass of simulated cached food. Using three sites in, north of, and south of Algonquin, we examined the hypothesis that warmer temperatures would negatively influence the preservation of cached food by accelerating decay. Food cached at the highest latitude site retained the greatest mass and caloric content over 180 days of exposure, but there was no difference between the intermediate and the low latitude sites. We also show that Algonquin experienced a winter climate similar to our northernmost site as recently as 1990, and our results suggest that food availability in Algonquin has likely decreased since then, due to a warming climate. Interestingly, this coincides with a decline in territory occupancy by Gray Jays in Algonquin. Our results point to a unique mechanism by which climate warming may influence the persistence of a boreal species through its influence on winter food availability.
Diameter-dependent thermodynamic and elastic properties of metallic nanoparticles
Authors: Chandra Jeewan , Kholiya Kuldeep
Published: April 2015

A simple theoretical model has been proposed to study the diameter-dependent properties of metallic nanoparticles, i.e. Ag , Au , Al , Ni , Pb , Cu and Fe . The diameter-dependent thermodynamic properties includes melting temperature, Debye temperature, evaporation temperature, melting enthapy and melting entropy. The model is also extended to study the diameter-dependent elastic properties including bulk modulus, Young's modulus and thermal expansion coefficient. On comparison with available experimental findings and other theoretical approaches, the results obtained with the present formulation depict a close agreement and demonstrate the validity of the method proposed in the present paper.
Stochastic resonance in second-order and underdamped asymmetric bistable system
Authors: Guo Yong-Feng , Shen Ya-Jun , Tan Jian-Guo
Published: April 2015

The phenomenon of stochastic resonance (SR) in a second-order and underdamped asymmetric bistable system is investigated. The second-order asymmetric bistable system with Gauss white noise is stochastically equivalent to two-dimensional Markovian process, and the exact expression of the signal-to-noise ratio (SNR) of system response in the presence of weak periodic driving force is obtained under the adiabatic condition and the theory of two-state model intensities. The influences of the damping parameter, asymmetry constant r and the Gaussian white noises on the SNR are discussed. The present calculation results show that, the increase of static asymmetry r and damping parameter γ can restrain the SR phenomenon appears. However, the increase of signal amplitude A can enhance SR.
Rigidity of gradient Einstein shrinkers
Authors: Catino Giovanni , Mazzieri Lorenzo , Mongodi Samuele
Published: April 2015

In this paper, we consider a perturbation of the Ricci solitons equation proposed in [J.-P. Bourguignon, Ricci curvature and Einstein metrics, in Global Differential Geometry and Global Analysis, Lecture Notes in Mathematics, Vol. 838 (Springer, Berlin, 1981), pp. 42–63] and studied in [H.-D. Cao, Geometry of Ricci solitons, Chinese Ann. Math. Ser. B27(2) (2006) 121–142] and we classify noncompact gradient shrinkers with bounded non-negative sectional curvature.
On right McCoy rings and right McCoy rings relative to u.p.-monoids
Authors: Mazurek Ryszard , Ziembowski Michał
Published: April 2015

In this paper, we prove that all right duo rings are right McCoy relative to any u.p.-monoid. We also show that for any nontrivial u.p.-monoid M, the class of right McCoy rings relative to M is contained in the class of right McCoy rings, and we present an example of a u.p.-monoid M for which this containment is strict.
THE INFLUENCE OF SLOW RECOVERY INSOLE ON PLANTAR PRESSURE AND CONTACT AREA DURING WALKING
Authors: NAEMI ROOZBEH , LINYARD-TOUGH KIMBERLEY , HEALY AOIFE , CHOCKALINGAM NACHIAPPAN
Published: April 2015

Plantar pressure assessment is commonly used as a tool to assess the efficacy of insoles in reducing the risk of mechanical trauma to the plantar soft tissue during walking gait. The slow rebound (SR) Poron insole is intended to provide a custom fit to the foot and is believed to be superior in increasing the contact area and consequently reducing the contact pressure compared to a normal Poron (NP) insole. The aim of this study was to compare the effectiveness of SR or NP versus an ethylene vinyl acetate (EV) insole in increasing the contact area (CA), and in reducing the contact pressure (CP) at different regions of the foot during walking. Plantar pressure data was collected from nine healthy individuals during walking using commercially available in-shoe plantar pressure sensors. Although, the NP insole significantly increased the CA and decreased the CP on the entire foot compared to the EV, there was no significant change in CP or CA at any region of the foot in any of the tested insoles. CP showed a positive significant correlation with CA at heel, hallux and heel center in all three insoles. The expected significant negative correlation between regional CA and CP was not observed.
A NEWLY DEVELOPED TRI-LEAFLET POLYMERIC HEART VALVE PROSTHESIS
Authors: DE GAETANO FRANCESCO , BAGNOLI PAOLA , ZAFFORA ADRIANO , PANDOLFI ANNA , SERRANI MARTA , BRUBERT JACOB , STASIAK JOANNA , MOGGRIDGE GEOFF D. , COSTANTINO MARIA LAURA
Published: April 2015

The potential of polymeric heart valves (PHV) prostheses is to combine the hemodynamic performances of biological valves with the durability of mechanical valves. The aim of this work is to design and develop a new tri-leaflet prosthetic heart valve (HV) made from styrenic block copolymers. A computational finite element model was implemented to optimize the thickness of the leaflets, to improve PHV mechanical and hydrodynamic performances. Based on the model outcomes, 8 prototypes of the designed valve were produced and tested in vitro under continuous and pulsatile flow conditions, as prescribed by ISO 5840 Standard. A specially designed pulse duplicator allowed testing the PHVs at different flow rates and frequency conditions. All the PHVs met the requirements specified in ISO 5840 Standard in terms of both regurgitation and effective orifice area (EOA), demonstrating their potential as HV prostheses.
CARDIAC REGIONAL FUNCTION OF YOUNG SPORTSMEN WITH FALSE TENDONS IN THE LEFT VENTRICLE
Authors: MEKHDIEVA K. , TIMOKHINA V. , SOKOLOV S. YU. , BLYAKHMAN F. A.
Published: April 2015

The aim of the study is to evaluate cardiac regional function of young athletes with false tendons (FT) in the left ventricle (LV). The focus was on mechanical asynchrony in LV wall. Forty-seven young athletes (mean age 20.2 ± 2.9 years) with connective tissue dysplasia syndrome underwent transthoracic echocardiography. To formalize FT topology, the 3D-model of LV geometry was reconstructed based on three short-axis sections and one long-axis section of LV. On average, 4.0 ± 1.0 FT with different localization and orientation in LV were determined. Cardiac function was estimated in 12 regions at LV long-axis section in the course of complete heart cycle. RMS variations of the regional systolic function duration (dT) and the variation coefficient of regional ejection fraction (Cv r-EF) for 12 regions served as measures of the mechanical asynchrony. Wide variety of asynchrony parameters was obtained. The value of dT varied from 24.2 to 84.1 ms (40.4 ± 27.8 ms); Cv r-EF — from 8.0% to 42.0% (20.83 ± 8.35%). Significant correlations between total number of FT per heart and dT (r = 0.396; P < 0.01) and between median transverse FT (connect interventricular septum and lateral LV wall) and Cv r-EF (r = 0.301; P < 0.05) were found. Detailed analyses of FT morphology with respect of LV regional function peculiarities showed that higher extent of asynchrony associates with the transverse and oblique FT mainly located at basal and/or medial portions of LV chamber.
CARDIAC APEX ROTATION ASSESSED BY AN IMPLANTABLE GYRO SENSOR: CORRELATION WITH A LV PRESSURE-DERIVED MYOCARDIAL PERFORMANCE INDEX IN EXPERIMENTALLY INDUCED ISCHEMIA
Authors: CERCENELLI L. , MARCELLI E.
Published: April 2015

Despite many investigators have focused attention on cardiac apex rotation (CAR) as a sensitive marker of left ventricle (LV) function, no studies have been specifically aimed to evaluate the correlation of CAR with myocardial performance index (MPI), a well-known index of both systolic and diastolic performance. In four sheep, we measured CAR using a miniature gyro sensor epicardically positioned at LV apex and we evaluated the beat-to-beat correlation between CAR and a myocardial performance index calculated from LV-pressure (LVP) measurements (MPILVP). We also compared CAR with hemodynamic parameters (LVdP/dtMAX, LVdP/dtMIN). A strong negative correlation was observed between CAR and MPILVP during the experimental cardiac conditions (baseline, acute ischemia induced by coronary ligation and release of ligation). At 30 s after ligation a marked decrease of CAR was observed, while LVdP/dtMAX showed minor changes. CAR has good potential to reflect changes of global myocardial performance and to predict hemodynamic changes in acute impairment of cardiac function.
A COMPUTATIONAL STUDY TO INVESTIGATE DEBONDING IN COATED BIORESORBABLE STENTS
Authors: WU WEI , MERCURI MASSIMILIANO , PEDRONI CHIARA , MIGLIAVACCA FRANCESCO , PETRINI LORENZA
Published: April 2015

A new trend in the treatment of atherosclerosis foresees the exploitation of bioresorbable materials for stents. Magnesium alloys are good candidates since they are completely biocorrodible in human body. To overcome the limitation of very fast degradation, the bioresorbable scaffold can be coated with a polymer having lower degradation rate and taking advantages by coupling metal and polymer properties. However, the coating has a risk of debonding due to the high strain the stent undergoes during the expansion. In this paper two-dimensional (2D) finite element analyses are performed to provide a greater understanding of coating delamination and to show how computational analyses can be usefully employed in the design of coated bioresorbable stents.
REAL-TIME LUNG TUMOUR MOTION MODELING FOR ADAPTIVE RADIATION THERAPY USING LEGO MINDSTORMS
Authors: GUIDI G. , MAFFEI N. , CIARMATORI A. , MISTRETTA M. G. , GOTTARDI G. , COSTI T. , GUIDI G. , MAFFEI N. , VECCHI C. , BALDAZZI G. , BERTONI F.
Published: April 2015

An anthropomorphic phantom was built using LEGO Mindstorms® and programmed in LabVIEW® for Adaptive Radiation Therapy (ART) purpose, to simulate the processes of breathing in the lung district during treatments. A thoracic cavity is prototyped by means of an 8 ribs apparatus and 2 artificial tumor masses, driven by intelligent brick LINUX® OS CPU. An optical surface tracking system (VisionRT®) and a QUASAR™ phantom allow correlation between physiological, robotic motion and surrogated signal. Patient's breathing phases are acquired instantaneously by InfraRed/UltraSound sensors. Through 4DCT images, tumor center of mass are individuated and tracked during respiration, to link internal–external organs motion. To quantify the degree of divergences due to dynamics organs deformation, a 4D function was obtained and simulated by our phantom. Sinusoidal signals (6, 10, 12, 15 and 17 Breaths per Minute-BPM) were used for evaluating and commissioning, thereby obtained a correlation coefficient (0.90–0.94) between QUASAR and LEGO. Validated on ideal conditions, phantom was tested in clinical practice. Breaths and CT study of 12 patients were analyzed. Fitting of real breath sinograms returned a mean R value of 0.94 (0.83–0.98) with best model performance achieved in signals with respiratory frequency less than 20 BPM. By using LEGO it is possible to reproduce real patients conditions and simulate normal and even abnormal behavior during the course of therapy, allowing spatial motion estimation.
ANALYSIS OF ANATOMICAL REGIONS IN ALZHEIMER'S BRAIN MR IMAGES USING LEVEL SETS AND MINKOWSKI FUNCTIONALS
Authors: KAYALVIZHI M. , ANANDH K. R. , KAVITHA G. , SUJATHA C. M. , RAMAKRISHNAN S.
Published: April 2015

In this work, an attempt is made to analyze anatomical regions of Alzheimer's brain MR images using level set and Minkowski functionals (MFs). The T1 weighted sagittal view of normal and abnormal images considered in this work, are obtained from MIRIAD database. The ventricle along with the hippocampus is segmented using Reaction Diffusion (RD) level set method and is subjected to further analysis using MFs. The prominent feature derived from the segmented region which contains ventricle and hippocampus is correlated with the Mini-Mental State Examination (MMSE) score. Results show that RD method is able to delineate the exact boundary of the ventricle along with hippocampus. It is observed that the MF-area of segmented region provides better discrimination of normal and abnormal subjects (p < 0.001) compared to the MF-perimeter and MF-Euler number. The correlation of the MMSE with prominent MF-area for normal, mild, moderate and severe are found to be 0.71, 0.82, 0.84 and 0.89, respectively. This suggests that characterization of brain structures using MFs improve the discrimination capability of brain disorders. Hence MF-area feature could be used for the study of progression in Alzheimer's disease (AD) like neurodegenerative disorders.
A MATHEMATICAL AND COMPUTATIONAL MODEL OF BLOOD FLOW REGULATION IN MICROVESSELS: APPLICATION TO THE EYE RETINA CIRCULATION
Authors: CAUSIN PAOLA , MALGAROLI FRANCESCA
Published: April 2015

This paper presents a mathematical model and a computational framework for the resolution of large networks of distensible blood microvessels characterized by a hierarchy of different diameters. We analyze the contribution of different distensibility relations, representing both active and passive responses in the case of the microvascular network in the eye retina. Model predictions indicate that, depending on the geometrical (hierarchical) location in the network, distensibility effects may be significantly different and lead, over long times, to possible geometrically-driven remodeling processes.
INVESTIGATION ON THE EFFECTS INDUCED BY TKA FEATURES ON TIBIO-FEMORAL MECHANICS PART I: FEMORAL COMPONENT DESIGNS
Authors: INNOCENTI BERNARDO , YAGÜE HÉCTOR ROBLEDO , BERNABÉ RAQUEL ALARIO , PIANIGIANI SILVIA
Published: April 2015

The lack of awareness of the exact number of instantaneous centers of knee flexion/extension rotation leads to the presence in the market of total knee arthroplasty (TKA) femoral components designed under different hypotheses. Although single radius (SR) designs are thought to replicate the physiological behavior in a more realistic way, surgeons do not always agree about the veracity of their theoretical advantages with respect to the multiple radii components (J-curve (JC) design). Apart from clinical studies, up to now, any literature study biomechanically and exhaustively compares these two TKA solutions, thus a finite element analysis (FEA) has been carried out. In particular, two models were defined to analyze the performance of a SR design and a JC design with the same tibial component during gait cycle and squat motor task. Tibio-femoral kinematics and kinetics have been investigated comparing the resulting contact area between components, internal–external (IE) rotation, position and magnitude of the center of total forces due to contact pressure and polyethylene von Misses stresses. Results demonstrate that, for low demanding tasks, there are no significant differences between the two designs, however, during the squat motor task, some changes in contact force and increases in polyethylene stress were identified for the SR solution.
VARIATION OF THE ANKLE MOTION WITH THE PIVOT-POINT POSITION AS PREDICTED BY A SPHERICAL MODEL OF THE JOINT
Authors: SANCISI NICOLA , NARDINI FABRIZIO , PARENTI-CASTELLI VINCENZO , BELVEDERE CLAUDIO , LEARDINI ALBERTO
Published: April 2015

Recent studies proved that the ankle unloaded motion is nearly spherical and can be accurately modeled by one degree-of-freedom spatial spherical mechanisms. Starting from relevant experimental data measured on nine specimens, the global optimal pivot-point (PP) position, i.e., the center of this spherical motion, is obtained in this study and the effect on ankle motion of the changing position of this PP is analyzed.
Technological Innovation and Adopter Self-Construal
Authors: Fazel Hesham , Laplume André O. , Muralidharan Etayankara
Published: April 2015

In this paper, we theorize that individuals who value independence and distinctiveness identify more with social identities as a result of adopting sustaining technological innovations. Conversely, individuals who value interdependence may become more independent as a result of adopting disruptive technological innovations. We argue that successive adoptions of technological innovation may expand and contract the breadth of adopters' collective identities. We discuss the implications of this conceptual paper and suggest avenues for future research at the nexus of technological innovation and cultural change.
Functional characterization of the human facilitative glucose transporter 12 (GLUT12) by electrophysiological methods
Authors: Pujol-Giménez Jonai , Pérez Alejandra , Reyes Alejandro M. , Loo Donald D. F. , Lostao Maria Pilar
Published: April 2015

GLUT12 is a member of the facilitative family of glucose transporters. The goal of this study was to characterize the functional properties of GLUT12, expressed in Xenopus laevis oocytes, using radiotracer and electrophysiological methods. Our results showed that GLUT12 is a facilitative sugar transporter with substrate selectivity: d-glucose ≥ α-methyl-d-glucopyranoside (α-MG) > 2-deoxy-d-glucose(2-DOG) > d-fructose = d-galactose. α-MG is a characteristic substrate of the Na+/glucose (SGLT) family and has not been shown to be a substrate of any of the GLUTs. In the absence of sugar, 22Na+ was transported through GLUT12 at a higher rate (40%) than noninjected oocytes, indicating that there is a Na+ leak through GLUT12. Genistein, an inhibitor of GLUT1, also inhibited sugar uptake by GLUT12. Glucose uptake was increased by the PKA activator 8-bromoadenosine 3′,5′-cyclic monophosphate (8-Br-cAMP) but not by the PKC activator phorbol-12-myristate-13-acetate (PMA). In high K+ concentrations, glucose uptake was blocked. Addition of glucose to the external solution induced an inward current with a reversal potential of approximately −15 mV and was blocked by Cl− channel blockers, indicating the current was carried by Cl− ions. The sugar-activated Cl− currents were unaffected by genistein. In high external K+ concentrations, sugar-activated Cl− currents were also blocked, indicating that GLUT12 activity is voltage dependent. Furthermore, glucose-induced current was increased by the PKA activator 8-Br-cAMP but not by the PKC activator PMA. These new features of GLUT12 are very different from those described for other GLUTs, indicating that GLUT12 must have a specific physiological role within glucose homeostasis, still to be discovered.