bluuebunny/crossref_metadata_2025_split huggingface dataset:
Feasibility of Dynamic Contrast-Enhanced Magnetic Resonance Imaging Using Low-Dose Gadolinium
Authors: He Dianning , Chatterjee Aritrick , Fan Xiaobing , Wang Shiyang , Eggener Scott , Yousuf Ambereen , Antic Tatjana , Oto Aytekin , Karczmar Gregory S. 
Published: April 2018

Objectives
This study investigates whether administration of low doses of gadolinium-based contrast agent (GBCA) for dynamic contrast-enhanced (DCE) magnetic resonance imaging (MRI) can be as effective as a standard dose in distinguishing prostate cancer (PCa) from benign tissue. In addition, we evaluated the combination of kinetic parameters from the low- and high-dose injection as a new diagnostic marker.

Materials and Methods
Patients (n = 17) with histologically confirmed PCa underwent preoperative 3 T MRI. Dynamic contrast-enhanced MRI images were acquired at 8.3-second temporal resolution with a low dose (0.015 mmol/kg) and close to the standard dose (0.085 mmol/kg) of gadobentate dimeglumine bolus injections. Low-dose images were acquired for 3.5 minutes, followed by a 5-minute gap before acquiring standard dose images for 8.3 minutes. The data were analyzed qualitatively to investigate whether lesions could be detected based on early focal enhancement and quantitatively by fitting signal intensity as a function of time with an empirical mathematical model to obtain a maximum enhancement projection (MEP) and signal enhancement rate (α).

Results
Both low- and standard-dose DCE-MRI showed similar sensitivity (13/26 = 50%) and lesion conspicuity score (4.0 ± 1.0 vs 4.2 ± 0.9; P = 0.317) for PCa diagnosis on qualitative analysis. Prostate cancer showed significantly increased α compared with benign tissue for low (9.98 ± 5.84 vs 5.12 ± 2.95 s−1) but not for standard (4.27 ± 2.20 vs 3.35 ± 1.48 s−1) dose. The ratio of low-dose α to standard-dose α was significantly greater (P = 0.02) for PCa (2.8 ± 2.3) than for normal prostate (1.6 ± 0.9), suggesting changes in water exchange and T2* effects associated with cancer. In addition, decreases in the percentage change in T1 relaxation rate as a function of increasing contrast media concentration (ie, the “saturation effect”) can also contribute to the observed differences in high-dose and low-dose α. Area under the receiver operating characteristic curve for differentiating PCa from benign tissue using α was higher for low dose (0.769) compared with standard dose (0.625). There were no significant differences between MEP calculated for PCa and normal tissue at the low and standard doses. Moderate significant Pearson correlation for DCE parameters, MEP (r = 0.53) and α (r = 0.58), was found between low and standard doses of GBCA.

Conclusions
These preliminary results suggest that DCE-MRI with a low GBCA dose distinguishes PCa from benign prostate tissue more effectively than does the standard GBCA dose, based on signal enhancement rate. Diagnostic accuracy is similar on qualitative assessment. Prostate cancer diagnosis may be feasible with DCE-MRI with low-dose GBCA. In addition, comparison of enhancement kinetics after low and high doses of contrast media may provide diagnostically useful information.
Does an Aerobic Exercise Improve Outcomes in Older Sedentary Nonspecific Low Back Pain Subjects? A Randomized Controlled Study
Authors: Barni Luca , Calabretta Lucrezia , Lepori Luca , Pasquetti Pietro , Gulisano Massimo , Freddolini Marco 
Published: April 2018

Purpose:
To demonstrate that a tailored, supervised aerobic exercise after a general back-school rehabilitation program will improve outcomes for older patients with low back pain more than the general back-school program alone.

Method:
Twenty-two older patients with chronic nonspecific low back pain were recruited for this study, and they were randomly assigned to a control or an interventional group. Both groups received a standard back-school program, while subjects in the intervention group received an additional 15 minutes of the aerobic training program. The numerical pain rating scale (NPRS) and the Roland-Morris Questionnaire (RMQ) were used to assess pain intensity and disability before and after the 5-week treatment in both the participants' groups.

Results:
Reduction percentage was found significantly increased in the interventional group when compared with the control group for both the NPRS and the RMQ index (P < .05).

Conclusion:
An adapted aerobic exercise, together with a standard back-school program, was effective in reducing pain symptoms and disability in low back pain subjects rather than the back-school program alone. This should be used as an advice to practitioners while managing low back pain.
The Effects of Ridged Perimeter Insoles on Gait Parameters in Older Adults
Authors: Evans Kimeran W. , Mancinelli Corrie 
Published: April 2018

Investigated:
The effects of prolonged ridged perimeter insole use on gait parameters in older adults.

Methods:
Twenty-two older adults were tested at baseline and after 6 weeks of insole wear using an instrumented walkway to determine the effects of insole wear on double limb support and gait velocity.

Conclusions:
Ridged perimeter insoles have a positive effect on gait characteristics when ambulating on level surface terrain. A statistically significant difference in double limb support time (P = .0297) was found. Gait velocity was not found to be statistically significant (P = .0947) but did demonstrate a mean increase of 0.06 m/s from baseline to 6 weeks.
Cyclophosphamide for Refractory Acute Cellular Rejection After Lung Transplantation
Authors: Naik Chetan , Moore Cody , Pipeling Matthew , D’Cunha Jonathan , Ruppert Kristine , Ensor Christopher , Morrell Matthew 
Published: April 2018

Background
Acute cellular rejection (ACR) is a major risk factor for chronic lung allograft dysfunction after lung transplantation. Acute cellular rejection can persist or recur despite augmentation of immunosuppression by conventional methods. There are limited therapeutic options in treating these recurrent and refractory ACRs. We describe our experience with cyclophosphamide therapy for recurrent and refractory ACR in lung transplant recipients.

Methods
Six consecutive patients who were treated with cyclophosphamide for recurrent or refractory ACR were included in the series. The primary outcome measures were improvement in ACR score and forced expiratory volume at 1 second. Secondary outcome measures included adverse drug events including bone marrow suppression, gastrointestinal side effects, and infections.

Results
Five of the 6 patients treated demonstrated complete resolution of ACR on follow-up biopsies. Acute cellular rejection score improved after cyclophosphamide treatment (P = 0.03). None of the patients had high grade (≥A3) ACR in the 3 months after cyclophosphamide administration. Cyclophosphamide had no effect on forced expiratory volume at 1 second trend or bronchiolitis obliterans score. All patients tolerated cyclophosphamide with minor gastrointestinal side effects, mild bone marrow suppression, and nonfatal infections that were amenable to treatment.

Conclusions
Cyclophosphamide therapy is an option in treating recurrent and refractory ACR in patients who have failed conventional treatments. Cyclophosphamide is tolerated well without serious adverse drug events (ADE).
A decay effect of the bacterial growth rate associated with genome reduction
Authors: Tsuchiya Kouhei , Cao Yang-Yang , Kurokawa Masaomi , Ashino Kazuha , Yomo Tetsuya , Ying Bei-Wen 
Published: April 2018

AbstractBacterial growth is an important topic in microbiology and of crucial importance to better understand living cells. Bacterial growth dynamics are quantitatively examined using various methods to determine the physical, chemical or biological features of growing populations. Due to methodological differences, the exponential growth rate, which is a parameter that is representative of growth dynamics, should be differentiated. This study experimentally verified the differentiation in growth rates attributed to different methodologies, and demonstrated that the most popular method, optical turbidity, led to the determination of a lower growth rate in comparison to the methods based on colony formation and ATP abundance, due to a decay effect of reading OD600 during a population increase. Accordingly, the logistic model, which is often applied to growth data reading the OD600, was revised by introducing a new parameter: the decay rate, to compensate for the lowered estimation in growth rates. The modified logistic model not only presented an improved goodness of fit in comparison to the original model but also led to an intriguing finding of a correlation between genome reduction and the decay rate. The decay effect seemed to be partially attributed to the decrease in cell size accompanied by a population increase and was medium dependent. In summary, the present study provides not only a better theoretical tool for the high-throughput studies on bacterial growth dynamics linking with experimental data using optical turbidity to the theoretical analysis with biological importance, but also a valuable insight for understanding the genome evolution and fitness increase in microbial life.
Experimental increases in glucocorticoids alter function of the HPA axis in wild red squirrels without negatively impacting survival and reproduction
Authors: van Kesteren Freya , Delehanty Brendan , Westrick Sarah E. , Palme Rupert , Boonstra Rudy , Lane Jeffrey E. , Boutin Stan , McAdam Andrew G. , Dantzer Ben 
Published: April 2018

AbstractHormones such as glucocorticoids (colloquially referred to as “stress hormones”) have important effects on animal behavior and life history traits, yet most of this understanding has come through correlative studies. While experimental studies offer the ability to assign causality, there are important methodological concerns that are often not considered when manipulating hormones, including glucocorticoids, in wild animals. In this study, we examined how experimental elevations of cortisol concentrations in wild North American red squirrels (Tamiasciurus hudsonicus) affected their hypothalamic–pituitary–adrenal (HPA) axis reactivity, and life history traits including body mass, litter survival, and adult survival. The effects of exogenous cortisol on plasma cortisol concentrations depended on the time between treatment consumption and blood sampling. In the first nine hours after consumption of exogenous cortisol, individuals had significantly higher true baseline plasma cortisol concentrations, but adrenal gland function was impaired as indicated by their dampened response to capture and handling and to injections of adrenocorticotropic hormone compared to controls. Approximately 24 hours after consumption of exogenous cortisol, individuals had much lower plasma cortisol concentrations than controls, but adrenal function was restored. Corticosteroid binding globulin (CBG) concentrations were also significantly reduced in squirrels treated with cortisol. Despite these profound shifts in the functionality of the HPA axis, squirrel body mass, offspring survival, and adult survival were unaffected by experimental increases in cortisol concentrations. Our results highlight that even short-term experimental increases in glucocorticoids can affect adrenal gland functioning and CBG concentrations but without other side-effects.
Ataxin-7 and Non-stop coordinate SCAR protein levels, subcellular localization, and actin cytoskeleton organization
Authors: Cloud Veronica , Thapa Ada , Morales-Sosa Pedro , Miller Tayla , Miller Sara , Holsapple Daniel , Gerhart Paige , Momtahan Elaheh , Jack Jarrid L. , Leiva Edgardo , Rapp Sarah , Shelton Lauren G. , Pierce Richard A , Martin-Brown Skylar , Florens Laurence , Washburn Michael P , Mohan Ryan D. 
Published: April 2018

AbstractAtaxin-7 (Atxn7), a subunit of the SAGA chromatin remodeling complex, is subject to polyglutamine expansion at the amino terminus, causing spinocerebellar ataxia type 7 (SCA7), a progressive retinal and neurodegenerative disease. Within SAGA, the amino terminus of Atxn7 anchors the Non-stop deubiquitinase to the complex. To understand the consequences of Atxn7-dependent regulation of Non-stop, we sought substrates for Non-stop and discovered the deubiquitinase, dissociated from SAGA, interacts with Arp2/3 and WAVE regulatory complexes (WRC). Protein levels of WRC subunitsuppressor of extracellularcAMPreceptor (cAR) (SCAR) are regulated by a constant ubiquitination/proteasomal degradation mechanism. Loss of Atxn7 frees Non-stop from SAGA, leading to increased Non-stop interaction with SCAR and also increased SCAR protein levels. A Non-stop enzymatic pocket mutation that increases binding to ubiquitin increased interaction with SCAR, while an enzymatic pocket mutation reducing binding to ubiquitin also reduced binding to SCAR. Loss of Non-stop increased polyubiquitination of SCAR and reduced SCAR protein levels although SCAR protein levels were rescued by protease inhibition. Dependent on conservedWRC interactingreceptorsequences (WIRS), Non-stop overexpression increased SCAR protein levels and directed subcellular localization of SCAR, leading to decreased cell area and decreased number of protrusions.In vivo, heterozygous mutation of Atxn7 rescued haploinsufficiency of SCAR to produce F actin, but heterozygous mutation of SCAR did not significantly rescue retinal axon mistargeting upon knockdown of Atxn7.SummarySAGA subunits Ataxin-7 and Non-stop regulate stability and subcellular localization of WRC subunit SCAR. Loss of Ataxin-7 increases, while loss of Non-stop decreases, SCAR protein levels and F-actin network assembly.
Broad-spectrum adaptive antibiotic resistance associated with Pseudomonas aeruginosa mucin-dependent surfing motility
Authors: Sun Evelyn , Gill Erin E. , Falsafi Reza , Yeung Amy , Liu Sijie , Hancock Robert E.W. 
Published: April 2018

AbstractSurfing motility is a novel form of surface adaptation exhibited by the nosocomial pathogen, Pseudomonas aeruginosa, in the presence of the glycoprotein mucin that is found in high abundance at mucosal surfaces especially the lungs of cystic fibrosis and bronchiectasis patients. Here we investigated the adaptive antibiotic resistance of P. aeruginosa under conditions in which surfing occurs compared to cells undergoing swimming. P. aeruginosa surfing cells were significantly more resistant to several classes of antibiotics including aminoglycosides, carbapenems, polymyxins, and fluroquinolones. This was confirmed by incorporation of antibiotics into growth medium, which revealed a concentration-dependent inhibition of surfing motility that occurred at concentrations much higher than those needed to inhibit swimming. To investigate the basis of resistance, RNA-Seq was performed and revealed that surfing influenced the expression of numerous genes. Included amongst genes dysregulated under surfing conditions were multiple genes from the Pseudomonas resistome, which are known to affect antibiotic resistance when mutated. Screening transposon mutants in these surfing-dysregulated resistome genes revealed that several of these mutants exhibited changes in susceptibility to one or more antibiotics under surfing conditions, consistent with a contribution to the observed adaptive resistance. In particular, several mutants in resistome genes, including armR, recG, atpB, clpS, nuoB, and certain hypothetical genes such as PA5130, PA3576 and PA4292, showed contributions to broad-spectrum resistance under surfing conditions and could be complemented by their respective cloned genes. Therefore, we propose that surfing adaption led to extensive multidrug adaptive resistance as a result of the collective dysregulation of diverse genes.
Construction of a novel phagemid to produce custom DNA origami scaffolds
Authors: Nafisi Parsa M. , Aksel Tural , Douglas Shawn M. 
Published: April 2018

AbstractDNA origami, a method for constructing nanoscale objects, relies on a long single strand of DNA to act as the “scaffold” to template assembly of numerous short DNA oligonucleotide “staples”. The ability to generate custom scaffold sequences can greatly benefit DNA origami design processes. Custom scaffold sequences can provide better control of the overall size of the final object and better control of low-level structural details, such as locations of specific base pairs within an object. Filamentous bacteriophages and related phagemids can work well as sources of custom scaffold DNA. However, scaffolds derived from phages require inclusion of multi-kilobase DNA sequences in order to grow in host bacteria, and thus cannot be altered or removed. These fixed-sequence regions constrain the design possibilities of DNA origami. Here we report the construction of a novel phagemid, pScaf, to produce scaffolds that have a custom sequence with a much smaller fixed region of only 381 bases. We used pScaf to generate new scaffolds ranging in size from 1,512 to 10,080 bases and demonstrated their use in various DNA origami shapes and assemblies. We anticipate our pScaf phagemid will enhance development of the DNA origami method and its future applications.
The histone chaperone FACT modulates nucleosome structure by tethering its components
Authors: Wang Tao , Liu Yang , Edwards Garrett , Krzizike Daniel , Scherman Hataichanok , Luger Karolin 
Published: April 2018

AbstractHuman FACT (hFACT) is a conserved histone chaperone that was originally described as a transcription elongation factor with potential nucleosome assembly functions. Here we show that FACT facilitates tetrasome assembly and H2A-H2B deposition to form hexasomes and nucleosomes. In the process, FACT tethers components of the nucleosome through interactions with H2A-H2B, resulting in a defined intermediate complex comprised of FACT, a histone hexamer and DNA. Free DNA extending from the tetrasome then competes FACT off H2A-H2B, thereby promoting hexasome and nucleosome formation. Our studies provide mechanistic insight into how FACT may stabilize partial nucleosome structures during transcription or nucleosome assembly, seemingly facilitating nucleosome disassembly and nucleosome assembly.
A Hierarchical Clustering Algorithm Based on Silhouette Index for Cancer Subtype Discovery from Omics Data
Authors: Nidheesh N. , Abdul Nazeer K.A. , Ameer P.M. 
Published: April 2018

AbstractCancer subtype discovery fromomicsdata requires techniques to estimate the number of natural clusters in the data. Automatically estimating the number of clusters has been a challenging problem in Machine Learning. Using clustering algorithms together with internal cluster validity indexes have been a popular method of estimating the number of clusters in biomolecular data. We propose a Hierarchical Agglomerative Clustering algorithm, namedSilHAC, which can automatically estimate the number of natural clusters and can find the associated clustering solution.SilHACis parameterless. We also present two hybrids ofSilHACwithSpectral ClusteringandK-Meansrespectively as components.SilHACand the hybrids could find reasonable estimates for the number of clusters and the associated clustering solution when applied to a collection of cancer gene expression datasets. The proposed methods are better alternatives to the ‘clustering algorithm - internal cluster validity index’ pipelines for estimating the number of natural clusters.
Linkages between tourism and agriculture for inclusive development in Tanzania
Authors: Anderson Wineaster 
Published: April 2018

Purpose
The purpose of this paper is to examine how local agricultural communities are integrated into the tourism value chains and provide insights into how this can contribute to poverty reduction.

Design/methodology/approach
The study employed the value chain approach to gain an understanding of the linkages between tourism and agriculture. Interviews involving local suppliers of agricultural products and tourism businesses (n=195) were conducted in Lushoto, Tanzania. The livelihood portfolios (range of activities – farming, employment, tourism, etc.) were analyzed in terms of the resources (economic, natural, human, physical and social assets) available to individuals and households and how these are optimally used to achieve inclusive growth.

Findings
The findings show that the form of tourism business ownership and the presence of specific social networks between tourism businesses and local suppliers dictate the mode of buying and the strength of supply chains. Community-based tourism is dominant in the area, allowing tourists to interact with agrarian rural communities. However, the optimal local linkages have been hampered by the quantitative and qualitative mismatch between locally supplied products and the tourism sector’s requirements. The failure of many initiatives aimed at addressing the mismatch creates a need for empowering local communities to enable them to take the opportunities that tourism provides.

Practical implications
Least developed countries need to build on the lessons learned from the development of tourism in their local settings, and pursue strategies which bring hope, confidence and real benefits to the majority of the struggling population. This study gives an insight on how inter-sectoral linkages could be embraced among the strategies or means of reducing rampant poverty.

Originality/value
Linking local agricultural production to tourism has long been seen as a promising way to make tourism more economically inclusive. However, the use of value chain approach in studying the tourism-agriculture linkages for inclusive development, especially in the developing economies is not common. While employing Porter’s value chains analysis, this study provides insights into how local farmers can be incorporated in tourism food supply chains in an ethical and beneficial way.
A stress distribution modelization of a neat fit pin-loaded hub
Authors: Marouani Haykel , Hassine Tarek 
Published: April 2018

PurposePin-loaded hubs with fitted bush are used in industrial connector-type elements. They are subjected to varying radial forces leading to variable stress distribution. The literature provides various pressure distribution expressions adapted essentially for symmetric geometries and fixed load condition (circular hubs, half-infinite geometries, axial load, tangential load, etc.). This study aims to take into account the geometrical conditions of industrial connector-type elements and presents a model for pressure distribution based only on geometric parameters, maximal pressure and contact angle value for the case of fit pin-loaded hub.Design/methodology/approachThe finite element computation for the contact problem shows that the pressure distribution of the pin-loaded hub under various inclined forces (from 0° to 180°) is a parabolic distribution. This distribution can be defined by three parameters which areθA,θBandPmax. The study assumes that the distribution is symmetric and thatPmaxcan be modeled using forceF, hub radiusR, hub thicknessband the half contact angle areθA.FindingsThe new proposal pressure distribution parameters are easy to identify. Even for the non-symmetric pressure distribution, the study denotes that the errors on evaluatingθAandθBkeep the analytical model still in good agreement with finite element computations.Research limitations/implicationsOnly the neat fit case was studied.Practical/implicationsPin-loaded joints are connector-type elements used in mechanical assemblies to connect any structural components and linkage mechanisms such as connecting rod ends of automotive or shear joints for aircraft structure.Originality/valueThe good correlation between finite element computations and model results shows the validity of the assumptions adopted here. Analytical fatigue models, based on this stress distribution, could be derived in view of a fatigue lifetime calculation on connecting hub. Friction, pin deformation and local plastic effects under pin-loading are the main phenomena to take into account to further enrich this model.