bluuebunny/crossref_metadata_2025 huggingface dataset:
Characterization of Methyltransferase AlmCII in Chalcomycin Biosynthesis: The First TylF Family O‐Methyltransferase Works on a 4′‐Deoxysugar
Authors: Dai Ping , Wang Chuan‐Xi , Gao Hao , Wang Qiao‐Zhen , Tang Xiao‐Long , Chen Guo‐Dong , Hong Kui , Hu Dan , Yao Xin‐Sheng
Published: May 2017

Sugar O‐methylation is a ubiquitous modification in natural products and plays diverse roles. This realization has inspired many attempts to search for novel methyltransferases. Chalcomycins are a group of 16‐membered macrolides containing two methylated sugars that require three methyltransferases for their biosynthesis. Here, we identified that AlmCII, a sugar O‐methyltransferase belonging to the TylF family that was previously only known to methylate sugars with a 4′‐hydroxy group, can methylate a 4′,6′‐dideoxysugar during the biosynthesis of chalcomycins. An in vitro enzymatic assay revealed that AlmCII is divalent metal‐dependent with an optimal pH of 8.0 and optimal temperature of 42 °C. Moreover, the 3′‐O‐demethylated chalcomycins exhibit less than 6 % of the antibacterial activity of their parent compounds. This is the first report demonstrating that a TylF family O‐methyltransferase can use a 4′‐deoxy sugar as a substrate and highlighting the importance of this methylation for the antibacterial activity of chalcomycins.
Predicting Early Readmission Following PCI: A Work in Progress
Authors: Belardi Jorge A. , Albertal Mariano
Published: May 2017

Key Points

Early hospital readmissions after percutaneous coronary interventions (PCI) are common and costly.

From the NCDR CathPCI Registry and the Centers for Medicare and Medicaid Services, a risk prediction model was generated using 14 clinical variables, demonstrating modest discrimination.

Future research is needed to identify interventions aim to reduce early readmissions. The use of this risk model may help guide these interventions.
Large device for large atrial septal defects—the 40 mm Atrial Septal Occluder
Authors: Feldman Ted
Published: May 2017

Key Points

The 40 mm ASO device can be used with a high rate of successful implantation for ASD closure

The technique of implantation usually requires more than simple direct, device placement

Balloon‐assisted technique (BAT) can make use of this large occluder more predictable

Experience contributes significantly to procedure success

Important complications, such as device embolization will occur in a small number of cases

Thrombotic complications are infrequent, even with aspirin monotherapy
Revisiting Femoral vs. Radial access—do vascular closure devices level the playing field?
Authors: Pasala Tilak K. R. , Turi Zoltan G.
Published: May 2017

Key Points

Previous large randomized multicenter trials have shown superiority of radial to femoral access in reducing major bleeding, vascular complications, and in some cohorts, mortality

Vascular closure devices improve time to hemostasis and ambulation, as well as patient comfort, but have not been shown to reduce major complications or mortality consistently in the high level evidence base.

The combination of optimal femoral access and closure with a vascular closure device has the potential to narrow the gap between the radial and femoral approaches in high risk patients, but unfortunately this study was too limited to confirm either non‐inferiority or equivalence
Thin‐walled access sheath to hold a larger guide: New technology specifically for transradial access
Authors: Davies Rhian E. , Gilchrist Ian C.
Published: May 2017

Key Points

Vascular access sheaths are now available with thin walls specifically designed for transradial use.

A thin‐walled sheath with an outside diameter on the same order of size as a 6‐F traditional sheath can carry a 7‐F guiding catheter.

While the larger‐sized guides may increase the interventional options for the radial operator, a hazard from vascular damage due to the larger‐sized lumens may exist and points to a need for further improvement in radial specific equipment.
Improved equipment used by knowledgeable operators does reduce radiation
Authors: Balter Stephen
Published: May 2017

Key Points

Improvements in fluoroscopic equipment design and configuration facilitates radiation reduction.

Operators should exploit improved equipment and fully apply procedural radiation management techniques.

Less radiation did not impair the success rate of treating complex CTO lesions.
Preventing and treating coronary perforations: Lessons from disaster management
Authors: Sandoval Yader , Brilakis Emmanouil S.
Published: May 2017

Key Points

Coronary artery perforations (CAP) are rare in patients undergoing routine PCI with recent contemporary databases reporting an incidence ∼0.3%.

Older age, cardiomyopathy or left ventricular dysfunction, mechanical circulatory support prior to PCI, and CTO lesions have the strongest association with CAP.

Prevention, early detection, preparedness and familiarity with the equipment used to treat perforations (such as efficient use of covered stents, and fat or coil embolization) and regrouping to examine and educate about these experiences are key for improving our response to cath lab disasters.
End‐stage renal disease and severe aortic stenosis. Does valve replacement improve one‐year outcomes?
Authors: Alraies M. Chadi , Satler Lowell F.
Published: May 2017

Key Points

TAVR or SAVR has a 1‐year survival benefit over BAV alone in patients with severe symptomatic AS and ESRD on dialysis

More studies comparing SAVR vs. TAVR outcome in ESRD patients and severe AS are needed to understand further the patients that will benefit the most in terms of quality of life.

The heart team approach for treatment of patients with ESRD and severe AS remains extremely important to optimize patient's outcome.
Case report of myometrial window following fetoscopic treatment of twin‐twin transfusion syndrome: indications of underlying collagen vascular disease?
Authors: Zaretsky Michael V. , Manchester David K. , Galan Henry L. , Behrendt Nicholas J. , Marwan Ahmed I. , Liechty Kenneth W. , Crombleholme Timothy M.
Published: May 2017

Key Clinical Message

Intraperitoneal amniotic fluid leak is a known complication of fetoscopic procedures that usually resolves spontaneously with expectant management. Intraperitoneal amniotic fluid leak may persist after fetoscopic procedures due to a myometrial window as well as to persistent chorioamniotic membrane disruption, which may be amenable to surgical repair.
Identification of EPCAM mutation: clinical use of microarray
Authors: Tan Queenie K.‐G. , Cardona Diana M. , Rehder Catherine W. , McDonald Marie T.
Published: May 2017

Key Clinical Message

We report a case of an infant with congenital tufting enteropathy (CTE) who presented with severe failure to thrive despite multiple interventions. This study illustrates that CTE may be missed by endoscopy, and the use of chromosomal microarray and immunohistological analysis may be integral to diagnosis.
Prenatal identification of two discontinuous maternally inherited chromosome 7q36.3 microduplications totaling 507 kb including the sonic hedgehog gene in a fetus with multiple congenital anomalies
Authors: Micale Mark , Embrey Bedford , Hubbell Katie , Beaudry‐Rogers Kelly , Whitten Amy
Published: May 2017

Key Clinical Message

Duplications of the SHH gene, an important developmental gene, are rare. Disruption of this gene produces a variable phenotype in humans from major anomalies to isolated facial defects. This is the first reported case of a maternally inherited 507 kb discontinuous chromosome 7q36.3 microduplication resulting in duplication of SHH and nearby enhancer sequences.
Colchicine reduced pericardial effusion due to postcardiac injury syndrome following cardiac resynchronization therapy implantation
Authors: Hoshiyama Tadashi , Ashikaga Keiichi , Tsujita Kenichi , Shibata Yoshisato
Published: May 2017

Key Clinical Message

We present a case of postcardiac injury syndrome with pericardial effusion following cardiac resynchronization therapy implantation which was treated by only colchicine. Although treatment using colchicine is not as common as NSAIDs or steroids, colchicine seems to be an effective and safe treatment option for the syndrome.
Metastatic pulmonary artery sarcoma presented with tamponade: a case report
Authors: Hajsadeghi Shokoufeh , Kooranifar Siavash , Ansarinejad Nafise , Sadeghipour Alireza , Iranpour Aida , Aziz Ahari Alireza
Published: May 2017

Key Clinical Message

Pulmonary artery sarcoma is a rare tumor with varying presentations including pericardial effusion and pulmonary metastasis. Single‐nucleotide polymorphism array is a novel method that can be used to define tumor genome and be used as a guidance to choose the proper treatment regimen.
A pH‐Responsive DNAsome from the Self‐Assembly of DNA–Phenyleneethynylene Hybrid Amphiphile
Authors: Albert Shine K. , Golla Murali , Thelu Hari Veera Prasad , Krishnan Nithiyanandan , Varghese Reji
Published: May 2017

A pH‐responsive DNAsome derived from the amphiphilicity‐driven self‐assembly of DNA amphiphile containing C‐rich DNA sequence is reported. The acidification of DNAsome induces a structural change of C‐rich DNA from random coil to an i‐motif structure that triggers the disassembly of DNAsome and its subsequent morphological transformation into an open entangled network. The encapsulation of a hydrophobic guest into the membrane of DNAsome and its pH‐triggered release upon acidification of DNAsome is also demonstrated.
Organocatalytic Stereoconvergent Synthesis of α‐CF3 Amides: Triketopiperazines and Their Heterocyclic Metamorphosis
Authors: Foster Robert W. , Lenz Eva N. , Simpkins Nigel S. , Stead Darren
Published: May 2017

The highly enantioselective alkylation of α‐CF3 enolates, generated from triketopiperazines, has been accomplished through use of a bifunctional thiourea organocatalyst to facilitate 1,4‐addition to varied enone acceptors. On treatment with appropriate nitrogen nucleophiles, the chiral triketopiperazine products undergo a metamorphosis, to provide novel fused heterocyclic lactams such as extended pyrazolopyrimidines.
Bimetallic Cooperativity in Proton Reduction with an Amido‐Bridged Cobalt Catalyst
Authors: Kpogo Kenneth K. , Mazumder Shivnath , Wang Denan , Schlegel H. Bernhard , Fiedler Adam T. , Verani Cláudio N.
Published: May 2017

The bimetallic catalyst [CoII2(L1)(bpy)2]ClO4 (1), in which L1 is an [NN′2O2] fused ligand, efficiently reduced H+ to H2 in CH3CN in the presence of 100 equiv of HOAc with a turnover number of 18 and a Faradaic efficiency of 94 % after 3 h of bulk electrolysis at −1.6 V (vs. Ag/AgCl). This observation allowed the proposal that this bimetallic cooperativity is associated with distance, angle, and orbital alignment of the two Co centers, as promoted by the unique Co−Namido−Co environment offered by L1. Experimental results revealed that the parent [CoIICoII] complex undergoes two successive metal‐based 1 e− reductions to generate the catalytically active species [CoICoI], and DFT calculations suggested that addition of a proton to one CoI triggers a cooperative 1 e− transfer by each of these CoI centers. This 2 e− transfer is an alternative route to generate a more reactive [CoII(CoII−H−)] hydride, thus avoiding the CoIII−H− required in monometallic species. This [CoII(CoII−H−)] species then accepts another H+ to release H2.
Synthesis of Substituted Naphtho‐Ferrocenes via a Gold(I)‐Catalyzed Intramolecular 6‐endo‐Dig Cyclization
Authors: Zhang Pei‐Chao , Wang Yidong , Qian Deyun , Li Wenbo , Zhang Junliang
Published: May 2017

A novel series of naphtho‐ferrocene derivatives were synthesized in high yields by an efficient gold‐catalyzed intramolecular 6‐endo‐dig cyclization strategy. The salient features of this reaction include easy operation, broad substrate scope, high yields, mild conditions and it works well in wet solvent under air at room temperature.
Outcomes for patients with locally advanced pancreatic adenocarcinoma treated with stereotactic body radiation therapy versus conventionally fractionated radiation
Authors: Zhong Jim , Patel Kirtesh , Switchenko Jeffrey , Cassidy Richard J. , Hall William A. , Gillespie Theresa , Patel Pretesh R. , Kooby David , Landry Jerome
Published: May 2017

BACKGROUND

As systemic therapy has improved for locally advanced pancreatic cancer (LAPC), efforts to improve local control with optimal radiotherapy may be critical. Although conventionally fractionated radiation therapy (CFRT) has more recently shown a limited role in LAPC, stereotactic body radiation therapy (SBRT) is an emerging approach with promising results. With no studies to date comparing SBRT with CFRT for LAPC, this study used the National Cancer Data Base (NCDB) to evaluate these 2 modalities.

METHODS

With the NCDB, patients with American Joint Committee on Cancer cT2‐4/N0‐1/M0 adenocarcinoma of the pancreas diagnosed from 2004 to 2013 were analyzed. Radiation therapy delivered at ≤2 Gy was deemed CFRT, and radiation therapy delivered at ≥4 Gy per fraction was considered SBRT. Kaplan‐Meier analysis, log‐rank testing, and multivariate Cox proportional hazards regression were performed with overall survival (OS) as the primary outcome. Propensity score matching was used.

RESULTS

Among 8450 patients, 7819 (92.5%) were treated with CFRT, and 631 (7.5%) underwent SBRT. Receipt of SBRT was associated with superior OS in the multivariate analysis (hazard ratio, 0.84; 95% confidence interval, 0.75‐0.93; P < .001). With propensity score matching, 988 patients in all were matched, with 494 patients in each cohort. Within the propensity‐matched cohorts, the median OS (13.9 vs 11.6 months) and the 2‐year OS rate (21.7% vs 16.5%) were significantly higher with SBRT versus CFRT (P = .0014).

CONCLUSIONS

In this retrospective review using a large national database, SBRT was associated with superior OS in comparison with CFRT for LAPC, and these findings remained significant in a propensity‐matched analysis. Further prospective studies investigating these hypothesis‐generating results are warranted. Cancer 2017;123:3486‐93. © 2017 American Cancer Society.
Soft tissue sarcoma nomograms and their incorporation into practice
Authors: Callegaro Dario , Miceli Rosalba , Mariani Luigi , Raut Chandrajit P. , Gronchi Alessandro
Published: May 2017

The accurate prediction of prognosis in patients with soft tissue sarcoma (STS) is a challenging issue. Extreme variability in the clinical and pathological characteristics of this family of tumors hinders the simple stratification of patients into meaningful prognostic cohorts. Precision medicine tools for the prediction of prognosis, such as nomograms, enable personalized computation of outcome based on clinical and pathological characteristics of both patient and tumor. The eighth edition of the American Joint Committee on Cancer staging manual moved from a “population‐based” to a “personalized” approach endorsing high‐quality nomograms to improve clinician prediction ability in definite patient subgroups. The first nomogram for STS was published in 2002, and this was followed by several prognostic predictors offered to clinicians. Focusing on a specific STS subgroup or site, nomograms can take into consideration highly specific factors relevant only in that particular scenario, thereby maximizing prognostic ability. The objective of this review was to critically evaluate available nomograms for patients with STS to provide clinicians and researchers with a choice of the most optimal tool for each specific patient. Cancer 2017;123:2802–20. © 2017 American Cancer Society.
Hepatitis B virus screening and reactivation and management of patients with nasopharyngeal carcinoma: A large‐scale, big‐data intelligence platform–based analysis from an endemic area
Authors: Lv Jia‐Wei , Chen Yu‐Pei , Huang Xiao‐Dan , Zhou Guan‐Qun , Chen Lei , Li Wen‐Fei , Tang Ling‐Long , Mao Yan‐Ping , Guo Ying , Xu Rui‐Hua , Ma Jun , Sun Ying
Published: May 2017

BACKGROUND

Chemotherapy, target therapy, and immunotherapy are increasingly being used in the systematic treatment of nasopharyngeal carcinoma (NPC), during which the occurrence of hepatitis B virus (HBV) reactivation might increase. However, data regarding HBV screening and reactivation and the clinical management of NPC patients with HBV infections are lacking. This study was aimed at clarifying the risk of reactivation for NPC patients on different regimens while providing evidence concerning HBV screening and management in an endemic area.

METHODS

With the NPC database from an established big‐data intelligence platform at Sun Yat‐Sen University Cancer Center in China, NPC patients who were diagnosed between 2008 and 2016 and underwent HBV screening and regular monitoring of liver enzymes and HBV deoxyribonucleic acid (DNA) were analyzed.

RESULTS

Among the 46,919 patients identified, the HBV screening rate was 24.8% (11,616 of 46,919). Among the screened patients with an HBV infection, regular monitoring of liver enzymes and HBV DNA occurred for 563 patients. The incidence of HBV reactivation and HBV‐related hepatitis was 9.1% (51 of 563) and 2.5% (14 of 563), respectively. The reactivation risk varied for different treatments and regimens and ranged from 0.0% to 21.4%. Detectable baseline HBV DNA (odds ratio [OR], 2.93; P < .01), the presence of liver metastasis at diagnosis (OR, 7.19; P < .01), and antiviral prophylaxis (OR, 0.29; P < .01) were significantly associated with reactivation.

CONCLUSIONS

In NPC patients with chronic HBV infections on high‐risk regimens, the reactivation risk is similar to or exceeds the risk associated with other immunosuppressive therapies for which screening and prophylaxis are recommended. Our findings, therefore, support HBV screening and prophylaxis for these patients, whereas regular monitoring might be appropriate for patients with resolved HBV infections or those receiving low‐risk regimens. Cancer 2017;123:3540‐9. © 2017 American Cancer Society.
Integrated Computational Protocol for the Analysis of Quadrupolar Splittings from Natural‐Abundance Deuterium NMR Spectra in (Chiral) Oriented Media
Authors: Navarro‐Vázquez Armando , Berdagué Philippe , Lesot Philippe
Published: May 2017

The front cover artwork is provided by Dr. Armando Navarro‐Vázquez from the department of fundamental chemistry of the Universidade Federal de Pernambuco (Brazil) as well as Dr. Philippe Berdagué and Dr. Philippe Lesot (DR CNRS), both from the Institut de Chimie Moléculaire et des Matériaux d'Orsay of the Université de Paris‐Sud/Paris‐Saclay (France). Graphically inspired by the famous word game «Scrabble», the image illustrates, through selected keywords, the analytical potential of a hyphenated computational protocol for investigating (achiral, prochiral or chiral) organic molecules by combining deuterium NMR spectroscopy at natural abundance level and chiral oriented systems, as described in their article. Read the full text of the article at 10.1002/cphc.201601423.
Attribute‐based online/offline signcryption scheme
Authors: Rao Y. Sreenivasa
Published: May 2017

The efficiency of computation is one of the prime concerns in public key cryptography. The notion of online/offline framework speeds up the process of encryption and signing. In this paper, we propose the firstattribute‐based online/offline signcryption scheme that is able to provide fine‐grained data access control with confidentiality, authenticity, signer anonymity, and public verifiability. The scheme supports large attribute universe and monotone Boolean function predicates. The size of the system public parameters in our scheme is constant, and the selective security of the scheme is realized in random oracle model. Note that, to the best of our knowledge, there is no normal attribute‐based signcryption scheme satisfying all the aforementioned functionality.
Mild, moderate, meaningful? Examining the psychological and functioning correlates of DSM‐5 eating disorder severity specifiers
Authors: Gianini Loren , Roberto Christina A. , Attia Evelyn , Walsh B. Timothy , Thomas Jennifer J. , Eddy Kamryn T. , Grilo Carlos M. , Weigel Thomas , Sysko Robyn
Published: May 2017

Objective

This study evaluated the DSM‐5 severity specifiers for treatment‐seeking groups of participants with anorexia nervosa (AN), the purging form of bulimia nervosa (BN), and binge‐eating disorder (BED).

Method

Hundred and sixty‐two participants with AN, 93 participants with BN, and 343 participants with BED were diagnosed using semi‐structured interviews, sub‐categorized using DSM‐5 severity specifiers and compared on demographic and cross‐sectional clinical measures.

Results

In AN, the number of previous hospitalizations and the duration of illness increased with severity, but there was no difference across severity groups on measures of eating pathology, depression, or measures of self‐reported physical or emotional functioning. In BN, the level of eating concerns increased across the severity groups, but the groups did not differ on measures of depression, self‐esteem, and most eating pathology variables. In BN, support was also found for an alternative severity classification scheme based upon number of methods of purging. In BED, levels of several measures of eating pathology and self‐reported physical and emotional functioning increased across the severity groups. For BED, however, support was also found for an alternative severity classification scheme based upon overvaluation of shape and weight. Preliminary evidence was also found for a transdiagnostic severity index based upon overvaluation of shape and weight.

Discussion

Overall, these data show limited support for the DSM‐5 severity specifiers for BN and modest support for the DSM‐5 severity specifiers for AN and BED.
Historical demography and genetic differentiation of the giant freshwater prawn Macrobrachium rosenbergii in Bangladesh based on mitochondrial and ddRAD sequence variation
Authors: Alam M. M. Mahbub , Westfall Kristen M. , Pálsson Snæbjörn
Published: May 2017

Macrobrachium rosenbergii, the giant freshwater prawn, is an important source of high quality protein and occurs naturally in rivers as well as commercial farms in South and South‐East Asia, including Bangladesh. This study investigated the genetic variation and population structure of M. rosenbergii sampled from four rivers in Bangladesh (sample size ranged from 19 to 20), assessing sequence variation, both in the mitochondrial cytochrome oxidase subunit 1 (CO1) gene and in 106 single nucleotide polymorphisms (SNPs) sampled randomly from the genome with double digest RAD sequencing (ddRADseq). The mitochondrial variation presented a shallow genealogy with high haplotype diversity (h = 0.95), reflecting an expansion in population size for the last ~82 kyr. Based on the CO1 variation the current effective population size (Ne) was 9.7 × 106 (CI: 1.33 × 106 – 35.84 × 106) individuals. A significant population differentiation was observed with the mitochondrial CO1 sequence variation and based on the ddRADseq variation, which could be traced to the divergence of the population in the Naf River in the South‐East border with Myanmar from the other populations. A differentiation in mtDNA haplotype frequencies was also observed between the Biskhali River and the Karnaphuli Rivers in eastern Bangladesh. This study demonstrated the use of high‐throughput genotyping based on the ddRADseq method to reveal population structure at a small geographical scale for an important freshwater prawn. The information from this study can be utilized for management and conservation of this species in Bangladesh.
B(C6F5)3‐Catalyzed Deoxygenation of Sulfoxides and Amine N‐Oxides with Hydrosilanes
Authors: Ding Fangwei , Jiang Yanqiu , Gan Shaoyan , Bao Robert Li‐Yuan , Lin Kaifeng , Shi Lei
Published: May 2017

An efficient strategy for the deoxygenation of sulfoxides and amine N‐oxides by using B(C6F5)3 and hydrosilanes was developed. This method provided the corresponding aromatic and aliphatic products in good to high yields and showed good functional‐group tolerance under mild conditions.
Palladium‐Catalyzed Selective Synthesis of Perfluoroalkylated Enynes from Perfluoroalkyl Iodides and Alkynes
Authors: Qi Xinxin , Ai Han‐Jun , Cai Chuang‐Xu , Peng Jin‐Bao , Zheng Feng , Wu Xiao‐Feng
Published: May 2017

An interesting palladium‐catalyzed procedure for the synthesis of perfluoroalkylated enynes from perfluoroalkyl iodides and alkynes was developed. The reaction proceeds through the addition of iodoperfluoroalkanes to terminal alkynes and subsequent Sonogashira coupling with the same alkynes. This transformation could be conducted under mild reaction conditions with high efficiency and selectivity. Good functional group compatibility was observed, and a variety of perfluoroalkylated enynes products were isolated in good to excellent yields.
Microwave‐Assisted Hydrothermal Synthesis of CuO–ZnO–ZrO2 as Catalyst for Direct Synthesis of Methanol by Carbon Dioxide Hydrogenation
Authors: Huang Chong , Mao Dongsen , Guo Xiaoming , Yu Jun
Published: May 2017

A series of CuO–ZnO–ZrO2 catalysts was prepared by a facile microwave‐assisted hydrothermal synthesis method and used for the direct synthesis of methanol by CO2 hydrogenation in a fixed‐bed reactor at 240 °C, 3.0 MPa, CO2/H2=1:3 (v/v), and space velocity of 2400 mL gcat−1 h−1. The effects of the hydrothermal synthesis temperature (80–150 °C) on the physicochemical properties and catalytic activity of the CuO–ZnO–ZrO2 catalysts were investigated by using several techniques, including XRD, N2 adsorption, reactive N2O adsorption, SEM with energy‐dispersive X‐ray spectroscopy, X‐ray photoelectron spectroscopy, temperature‐programmed reduction by H2, and the temperature‐programmed desorption of adsorbed CO2 and H2. The catalyst prepared at 120 °C possessed a high surface area, a high dispersion of Cu species, a high adsorption capacity for CO2 and H2, and thus exhibited a high CO2 conversion and methanol selectivity. The surface area of metallic Cu (SCu) is the critical factor in determining the activity of the CuO–ZnO–ZrO2 catalyst.
A distributed learning–based user association for heterogeneous networks
Authors: Hajijamali Arani Atefeh , Omidi Mohammad Javad , Mehbodniya Abolfazl , Adachi Fumiyuki
Published: May 2017

The coexistence of various base stations (BSs) in heterogeneous networks (HetNets) has emerged as a promising approach to meet the ever increasing network capacity. In these networks, one of the important issues is the problem of associating user equipments (UEs) to BSs. In this paper, we investigate the UE association (UEA) problem in heterogeneous networks and propose a load‐aware UEA mechanism based on the BSs' estimated load and signal‐to‐interference‐and‐noise ratio. The proposed mechanism can capture the trade‐off between UE's quality‐of‐service requirement and delay. We model this strategic UE‐BS association as a noncooperative game. To solve the game, we develop a fully distributed algorithm inspired by machine learning techniques, whereby the proposed UEA scheme corresponds to a Markov chain. In the proposed scheme, each UE senses its environment and decides which BS to select based on the satisfaction technique. Therefore, it achieves a high level of satisfaction for UEs. Furthermore, use of historical information helps UEs select BSs with better long‐term performance. Simulation results show that the proposed mechanism reduces fractional transfer time and the number of unsatisfied UEs, respectively, up to about 46% and 52.3% and improves BS throughput up to about 15.4% compared to a benchmark algorithm that is based on the received signal strength and the BS's estimated load.
Flow resistance equation for rills
Authors: Di Stefano Costanza , Ferro Vito , Palmeri Vincenzo , Pampalone Vincenzo
Published: May 2017

In this paper, a new flow resistance equation for rill flow was deduced applying dimensional analysis and self‐similarity theory. At first, the incomplete self‐similarity hypothesis was used for establishing the flow velocity distribution whose integration gives the theoretical expression of the Darcy–Weisbach friction factor. Then the deduced theoretical resistance equation was tested by some measurements of flow velocity, water depth, cross section area, wetted perimeter, and bed slope carried out in 106 reaches of some rills shaped on an experimental plot. A relationship between the velocity profile, the channel slope, and the flow Froude number was also established. The analysis showed that the Darcy–Weisbach friction factor can be accurately estimated by the proposed theoretical approach based on a power–velocity profile.
Dysregulated Metabolism of the Amyloid‐β Protein and Therapeutic Approaches in Alzheimer Disease
Authors: Kikuchi Kazunori , Kidana Kiwami , Tatebe Takuya , Tomita Taisuke
Published: May 2017

Amyloid‐β protein (Aβ) is the main component of senile plaques in the brains of Alzheimer disease (AD) patients. Aβ is proteolytically derived from amyloid‐β precursor protein by β‐ and γ‐secretases. Secreted Aβ is then eliminated from the central nervous system by multiple clearance mechanisms, including phagocytosis, immune responses, and proteolytic degradation. These dynamic metabolic processes, which are referred to as Aβ economy, regulate steady‐state brain Aβ levels. Familial AD‐linked genetic mutations augment the production and aggregation of Aβ. In contrast, rare genetic variants that reduce Aβ production were protective against AD. Moreover, decreased Aβ clearance has been demonstrated in sporadic AD patients, suggesting that dysregulation of Aβ economy contributes to the development of AD. Thus, several approaches to inhibit the production as well as to enhance the clearance of Aβ have been investigated as potential therapeutics against AD. In this manuscript, we introduce the molecules and cellular mechanisms involved in the regulation of Aβ economy and discuss the current understanding of these processes in the development of therapeutics against AD. J. Cell. Biochem. 118: 4183–4190, 2017. © 2017 Wiley Periodicals, Inc.
Theoretical insights into the nature of PtSn bond: Reevaluating the bonding/back‐bonding properties of trichlorostannate with comparison to the cyano ligand
Authors: Papp Tamara , Kollár László , Kégl Tamás
Published: May 2017

The coordinating properties of the trichlorostannate ligand in hydrido platinum trichlorostannato and platinum bis‐trichlorostannato complexes, containing various phosphine ligands, have been elucidated by means of charge decomposition analysis, the Ziegler‐Rauk Energy Decomposition with the Natural Orbitals for Chemical Valence, Domain‐Averaged Fermi Hole, and natural bond orbital methods. Trichlorostannate has been found to be a strong σ‐donor and a weak π‐acceptor ligand with coordination properties not far from those of the cyano ligand. For back‐bonding, the tin‐chlorineorbitals are mostly responsible. In contrast to previous assumptions, the 5d orbitals of tin play no role at all in the interaction with the platinum center. QTAIM calculations suggest, that the platinum‐tin interaction should be interpreted as donor–acceptor, rather than covalent type. Trichlorostannate has been found to have weaker trans influence in comparison to the cyano ligand. © 2017 Wiley Periodicals, Inc.
Four faces of the interaction between ions and aromatic rings
Authors: Papp Dóra , Rovó Petra , Jákli Imre , Császár Attila G. , Perczel András
Published: May 2017

Non‐covalent interactions between ions and aromatic rings play an important role in the stabilization of macromolecular complexes; of particular interest are peptides and proteins containing aromatic side chains (Phe, Trp, and Tyr) interacting with negatively (Asp and Glu) and positively (Arg and Lys) charged amino acid residues. The structures of the ion–aromatic‐ring complexes are the result of an interaction between the large quadrupole moment of the ring and the charge of the ion. Four attractive interaction types are proposed to be distinguished based on the position of the ion with respect to the plane of the ring: perpendicular cation–π (CP⊥), co‐planar cation–π (CP∥), perpendicular anion–π (AP⊥), and co‐planar anion–π (AP∥). To understand more than the basic features of these four interaction types, a systematic, high‐level quantum chemical study is performed, using the X– + C6H6, M+ + C6H6, X– + C6F6, and M+ + C6F6 model systems with X− = H−, F−, Cl−, HCOO−, CH3COO− and M+ = H+, Li+, Na+,
, CH3
, whereby C6H6 and C6F6 represent an electron‐rich and an electron‐deficient π system, respectively. Benchmark‐quality interaction energies with small uncertainties, obtained via the so‐called focal‐point analysis (FPA) technique, are reported for the four interaction types. The computations reveal that the interactions lead to significant stabilization, and that the interaction energy order, given in kcal mol−1 in parentheses, is CP⊥ (23–37) > AP⊥ (14–21) > CP∥ (9–22) > AP∥ (6–16). A natural bond orbital analysis performed leads to a deeper qualitative understanding of the four interaction types. To facilitate the future quantum chemical characterization of ion–aromatic‐ring interactions in large biomolecules, the performance of three density functional theory methods, B3LYP, BHandHLYP, and M06‐2X, is tested against the FPA benchmarks, with the result that the M06‐2X functional performs best. © 2017 Wiley Periodicals, Inc.
An alternative to the “Star Path” enhancement of the ADMA linear scaling method for protein modeling
Authors: Mezey Paul G. , Antal Zoltan
Published: May 2017

With the aim of improving the performance of macromolecular quantum chemistry conformation analysis and reaction path following methods, the Adjustable Density Matrix Assembler (ADMA) method has already been combined with some faster although less accurate density matrix extrapolation methods, such as the Löwdin‐Inverse‐Löwdin (LIL) extrapolation along a potential energy surface, and a strategically arranged back‐and‐forth switching between these methods has been proven to be advantageous. Here, an alternative approach is proposed and investigated, based on several actual test calculations, where the “inexpensive” LIL density matrix extrapolation steps are replaced by only somewhat more expensive, but still ADMA‐based calculations, where in the “rough‐search stage,” only interactions of shorter distances within the macromolecule are considered. It is shown that this approach is viable, as an alternative to the “Star Path” method including both ADMA and LIL steps. © 2017 Wiley Periodicals, Inc.
Producing DFT/MM enzyme reaction trajectories from SCC‐DFTB/MM driving forces to probe the underlying electronics of a glycosyltransferase reaction
Authors: Rogers Ian L. , Naidoo Kevin J.
Published: May 2017

The SCC‐DFTB/MIO/CHARMM free energy surface for a glycosyltransferase, TcTS, is benchmarked against a DFT/MM reaction trajectory using the same CHARMM MM force field ported to the NWChem package. The popular B3LYP functional, against which the MIO parameter set was parameterized is used to optimize TS structures and run DFT reaction dynamics. A novel approach was used to generate reaction forces from a SCC‐DFTB/MIO/CHARMM reaction surface to drive B3LYP/6‐31G/MM and B3LYP/6‐31G(d)/MM reaction trajectories. Although TS structures compare favorably, differences stemming primarily from a minimal basis set approximation prevented a successful 6‐31G(d) FEARCF reaction dynamics trajectory. None the less, the dynamic evolution of the B3LYP/6‐31G/MM‐computed electron density provided an opportunity to perform NBO analysis along the reaction trajectory. Here, we illustrate that a successful ab initio reaction trajectory is computationally accessible when the underlying potential energy function of the semi‐empirical method used to produce driving forces is sufficiently close to the ab initio potential. © 2017 Wiley Periodicals, Inc.
Mild mitochondrial uncoupling induces HSL/ATGL‐independent lipolysis relying on a form of autophagy in 3T3‐L1 adipocytes
Authors: Demine Stéphane , Tejerina Silvia , Bihin Benoît , Thiry Marc , Reddy Nagabushana , Renard Patricia , Raes Martine , Jadot Michel , Arnould Thierry
Published: May 2017

Obesity is characterized by an excessive triacylglycerol accumulation in white adipocytes. Various mechanisms allowing the tight regulation of triacylglycerol storage and mobilization by lipid droplet‐associated proteins as well as lipolytic enzymes have been identified. Increasing energy expenditure by inducing a mild uncoupling of mitochondria in adipocytes might represent a putative interesting anti‐obesity strategy as it reduces the adipose tissue triacylglycerol content (limiting alterations caused by cell hypertrophy) by stimulating lipolysis through yet unknown mechanisms, limiting the adverse effects of adipocyte hypertrophy. Herein, the molecular mechanisms involved in lipolysis induced by a mild uncoupling of mitochondria in white 3T3‐L1 adipocytes were characterized. Mitochondrial uncoupling‐induced lipolysis was found to be independent from canonical pathways that involve lipolytic enzymes such as HSL and ATGL. Finally, enhanced lipolysis in response to mitochondrial uncoupling relies on a form of autophagy as lipid droplets are captured by endolysosomal vesicles. This new mechanism of triacylglycerol breakdown in adipocytes exposed to mild uncoupling provides new insights on the biology of adipocytes dealing with mitochondria forced to dissipate energy.
Isotropic three‐dimensional T2 mapping of knee cartilage: Development and validation
Authors: Colotti Roberto , Omoumi Patrick , Bonanno Gabriele , Ledoux Jean‐Baptiste , van Heeswijk Ruud B.
Published: May 2017

Purpose

1) To implement a higher‐resolution isotropic 3D T2 mapping technique that uses sequential T2‐prepared segmented gradient‐recalled echo (Iso3DGRE) images for knee cartilage evaluation, and 2) to validate it both in vitro and in vivo in healthy volunteers and patients with knee osteoarthritis.

Materials and Methods

The Iso3DGRE sequence with an isotropic 0.6 mm spatial resolution was developed on a clinical 3T MR scanner. Numerical simulations were performed to optimize the pulse sequence parameters. A phantom study was performed to validate the T2 estimation accuracy. The repeatability of the sequence was assessed in healthy volunteers (n = 7). T2 values were compared with those from a clinical standard 2D multislice multiecho (MSME) T2 mapping sequence in knees of healthy volunteers (n = 13) and in patients with knee osteoarthritis (OA, n = 5).

Results

The numerical simulations resulted in 100 excitations per segment and an optimal radiofrequency (RF) excitation angle of 15°. The phantom study demonstrated a good correlation of the technique with the reference standard (slope 0.9 ± 0.05, intercept 0.2 ± 1.7 msec, R2 ≥ 0.99). Repeated measurements of cartilage T2 values in healthy volunteers showed a coefficient of variation of 5.6%. Both Iso3DGRE and MSME techniques found significantly higher cartilage T2 values (P < 0.03) in OA patients. Iso3DGRE precision was equal to that of the MSME T2 mapping in healthy volunteers, and significantly higher in OA (P = 0.01).

Conclusion

This study successfully demonstrated that high‐resolution isotropic 3D T2 mapping for knee cartilage characterization is feasible, accurate, repeatable, and precise. The technique allows for multiplanar reformatting and thus T2 quantification in any plane of interest.

Level of Evidence: 1

Technical Efficacy: Stage 2

J. Magn. Reson. Imaging 2018;47:362–371.
Use of LC–HRMS in full scan‐XIC mode for multi‐analyte urine drug testing – a step towards a ‘black‐box’ solution?
Authors: Stephanson N. N. , Signell P. , Helander A. , Beck O.
Published: May 2017

The influx of new psychoactive substances (NPS) has created a need for improved methods for drug testing in toxicology laboratories. The aim of this work was to design, validate and apply a multi‐analyte liquid chromatography–high‐resolution mass spectrometry (LC–HRMS) method for screening of 148 target analytes belonging to the NPS class, plant alkaloids and new psychoactive therapeutic drugs. The analytical method used a fivefold dilution of urine with nine deuterated internal standards and injection of 2 μl. The LC system involved a 2.0 μm 100 × 2.0 mm YMC‐UltraHT Hydrosphere‐C18 column and gradient elution with a flow rate of 0.5 ml/min and a total analysis time of 6.0 min. Solvent A consisted of 10 mmol/l ammonium formate and 0.005% formic acid, pH 4.8, and Solvent B was methanol with 10 mmol/l ammonium formate and 0.005% formic acid. The HRMS (Q Exactive, Thermo Scientific) used a heated electrospray interface and was operated in positive mode with 70 000 resolution. The scan range was 100–650 Da, and data for extracted ion chromatograms used ± 10 ppm tolerance. Product ion monitoring was applied for confirmation analysis and for some selected analytes also for screening. Method validation demonstrated limited influence from urine matrix, linear response within the measuring range (typically 0.1–1.0 μg/ml) and acceptable imprecision in quantification (CV <15%). A few analytes were found to be unstable in urine upon storage. The method was successfully applied for routine drug testing of 17 936 unknown samples, of which 2715 (15%) contained 52 of the 148 analytes. It is concluded that the method design based on simple dilution of urine and using LC–HRMS in extracted ion chromatogram mode may offer an analytical system for urine drug testing that fulfils the requirement of a ‘black box’ solution and can replace immunochemical screening applied on autoanalyzers. Copyright © 2017 John Wiley & Sons, Ltd.
Micro‐Raman analysis on the combined use of ammonium oxalate and ammonium phosphate for the consolidation and protection of carbonate stone artifacts
Authors: Osticioli Iacopo , Botticelli Guido , Matteini Paolo , Siano Salvatore , Pini Roberto , Matteini Mauro
Published: May 2017

Ammonium oxalate ((NH4)2C2O4, AmOx) and more recently di‐ammonium phosphate ((NH4)2HPO4, DAP) are used as inorganic agents in the conservation of cultural heritage for protection and consolidation of carbonate stone artifacts. In this work, we carry out a Raman investigation on the extent of penetration provided by a combined use of them. In particular, AmOx followed by DAP, DAP followed by AmOx, and a DAP + AmOx mixture are applied on tablets of pure CaCO3as well as on degraded marble samples. Then, cross‐sections of samples are analyzed in depth from surface to bulk. Characteristic differences in penetration depth of these agents and distribution of their products of interaction with the substrate are detected and discussed. A homogeneous distribution of whewellite inside the substrates down to a depth of ~1 mm was detected, which became larger in highly degraded regions of marble substrate. Ca‐phosphates in the form of hydroxyapatite were detected at greater depth (down to 2.5 mm), confirming better consolidating properties of DAP with respect of AmOx. Among the application methods tested in our investigation, the DAP followed by AmOx treatment appears the most effective. The discussion of results takes into consideration several aspects including solubility and interaction dynamics between reaction products as well as the peculiar morphological features of the artifact, which are evidenced to play a significant role in treatment choice. Copyright © 2017 John Wiley & Sons, Ltd.
Vibrational investigation of pressure‐ and temperature‐induced phase transitions in metal formates templated by ethylammonium ions
Authors: Ciupa Aneta , Ptak Maciej , Mączka Mirosław , da Silva Filho José Gadelha , Freire Paulo Tarso Cavalcante
Published: May 2017

We report for the first time phonon properties of [CH3CH2NH3][Mg(HCOO)3] (EtAMg). The studied compound undergoes two structural temperature‐induced phase transitions and temperature‐dependent Raman and infrared studies let us to obtain insight into mechanism of these transitions. In particular, very large broadening of infrared and Raman bands, attributed to vibrations of the NH3 groups, revealed highly dynamic nature of these groups in the both high‐temperature phases. This result indicates that the phase transitions at 374 and 426 K are associated with disordering of the template cations. Raman and infrared data also show that both phase transitions are accompanied by significant distortion of the anionic framework. We also present the pressure‐dependent Raman data of EtAMn framework up to 7.1 GPa. These data revealed presence of two pressure‐induced phase transitions, one between 3.7 and 4.0 GPa and second between 5.6 and 6.0 GPa. We discuss mechanisms of these transitions. Copyright © 2017 John Wiley & Sons, Ltd.
Liquid Crystal Elastomer Actuators from Anisotropic Porous Polymer Template
Authors: Wang Qian , Yu Li , Yu Meina , Zhao Dongyu , Song Ping , Chi Hun , Guo Lin , Yang Huai
Published: May 2017

Controlling self‐assembly behaviors of liquid crystals is a fundamental issue for designing them as intelligent actuators. Here, anisotropic porous polyvinylidene fluoride film is utilized as a template to induce homogeneous alignment of liquid crystals. The mechanism of liquid crystal alignment induced by anisotropic porous polyvinylidene fluoride film is illustrated based on the relationship between the alignment behavior of liquid crystals and surface microstructure of anisotropic polyvinylidene fluoride film. Liquid crystal elastomer actuators with fast responsiveness, large strain change, and reversible actuation behaviors are achieved by the photopolymerization of liquid crystal monomer in liquid crystal cells coated with anisotropic porous films.

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A proteomic‐based investigation of potential copper‐responsive biomarkers: Proteins, conceptual networks, and metabolic pathways featuring Penicillium janthinellum from a heavy metal‐polluted ecological niche
Authors: Feng Xin , Xu Jian , Liang Yu , Chen Guo‐Li , Fan Xian‐Wei , Li You‐Zhi
Published: May 2017

Filamentous fungi‐copper (Cu) interactions are very important in the formation of natural ecosystems and the bioremediation of heavy metal pollution. However, important issues at the proteome level remain unclear. We compared six proteomes from Cu‐resistant wild‐type (WT) Penicillium janthinellum strain GXCR and a Cu‐sensitive mutant (EC‐6) under 0, 0.5, and 3 mmol/L Cu treatments using iTRAQ. A total of 495 known proteins were identified, and the following conclusions were drawn from the results: Cu tolerance depends on ATP generation and supply, which is relevant to glycolysis pathway activity; oxidative phosphorylation, the TCA cycle, gluconeogenesis, fatty acid synthesis, and metabolism are also affected by Cu; high Cu sensitivity is primarily due to an ATP energy deficit; among ATP generation pathways, Cu‐sensitive and Cu‐insensitive metabolic steps exist; gluconeogenesis pathway is crucial to the survival of fungi in Cu‐containing and sugar‐scarce environments; fungi change their proteomes via two routes (from ATP, ATP‐dependent RNA helicases (ADRHs), and ribosome biogenesis to proteasomes and from ATP, ADRHs to spliceosomes and/or stress‐adapted RNA degradosomes) to cope with changes in Cu concentrations; and unique routes exist through which fungi respond to high environmental Cu. Further, a general diagram of Cu‐responsive paths and a model theory of high Cu are proposed at the proteome level. Our work not only provides the potential protein biomarkers that indicate Cu pollution and targets metabolic steps for engineering Cu‐tolerant fungi during bioremediation but also presents clues for further insight into the heavy metal tolerance mechanisms of other eukaryotes.