bluuebunny/crossref_metadata_2025 huggingface dataset:
The renal arterial resistance index: a marker of renal function with an independent and incremental role in predicting heart failure progression
Authors: Ciccone Marco Matteo , Iacoviello Massimo , Gesualdo Loreto , Puzzovivo Agata , Antoncecchi Valeria , Doronzo Annalisa , Monitillo Francesco , Citarelli Gaetano , Paradies Valeria , Favale Stefano
Published: February 2014

Aims

The renal arterial resistance index (RRI) is a measure of renal blood flow obtained by Doppler ultrasonography, which has been demonstrated to reflect both vascular and parenchymal renal abnormalities. The aim of the study was to evaluate clinical correlates and the prognostic relevance of RRI in a group of patients affected by chronic heart failure (CHF).

Methods and results

We enrolled 250 CHF outpatients in a stable clinical condition and receiving conventional therapy. Peak systolic velocity and end‐diastolic velocity of a segmental renal artery were obtained by pulsed Doppler flow. Then the RRI was calculated. Standard renal function assessment was obtained by the measurement of creatinine serum levels and the estimation of the glomerular filtration rate (GFR). During follow‐up (21.4 ± 11.3 months), 41 patients experienced heart failure progression (hospitalization and/or heart transplantation and/or death due to worsening heart failure). Considered as a continuous variable, RRI was associated with events at univariate [hazard ratio (HR) 1.14; 95% confidence interval (CI) 1.09–1.19; P < 0.001] as well as at multivariate Cox regression analysis (HR 1.08; 95% CI 1.02–1.13; P = 0.004) after correction for independent predictors of the reference model. When the RRI was added to the reference model including GFR, a significant improvement of reclassification according to both category‐free net reclassification improvement (NRI, 47%; 95% CI 13–80%; P = 0.006) and integrated discrimination improvement (IDI, 0.034; 95% CI 0.006–0.061; P = 0.016) was observed.

Conclusions

Quantification of arterial renal perfusion provides a new parameter that independently predicts CHF patient outcome, thus strengthening its possible role in current clinical practice in order to better characterize renal function and stratify patients' prognosis.
The kidney in congestive heart failure: ‘are natriuresis, sodium, and diuretics really the good, the bad and the ugly?’
Authors: Verbrugge Frederik H. , Dupont Matthias , Steels Paul , Grieten Lars , Swennen Quirine , Tang W.H. Wilson , Mullens Wilfried
Published: February 2014

This review discusses renal sodium handling in heart failure. Increased sodium avidity and tendency to extracellular volume overload, i.e. congestion, are hallmark features of the heart failure syndrome. Particularly in the case of concomitant renal dysfunction, the kidneys often fail to elicit potent natriuresis. Yet, assessment of renal function is generally performed by measuring serum creatinine, which has inherent limitations as a biomarker for the glomerular filtration rate (GFR). Moreover, glomerular filtration only represents part of the nephron's function. Alterations in the fractional reabsorptive rate of sodium are at least equally important in emerging therapy‐refractory congestion. Indeed, renal blood flow decreases before the GFR is affected in congestive heart failure. The resulting increased filtration fraction changes Starling forces in peritubular capillaries, which drive sodium reabsorption in the proximal tubules. Congestion further stimulates this process by augmenting renal lymph flow. Consequently, fractional sodium reabsorption in the proximal tubules is significantly increased, limiting sodium delivery to the distal nephron. Orthosympathetic activation probably plays a pivotal role in those deranged intrarenal haemodynamics, which ultimately enhance diuretic resistance, stimulate neurohumoral activation with aldosterone breakthrough, and compromise the counter‐regulatory function of natriuretic peptides. Recent evidence even suggests that intrinsic renal derangements might impair natriuresis early on, before clinical congestion or neurohumoral activation are evident. This represents a paradigm shift in heart failure pathophysiology, as it suggests that renal dysfunction—although not by conventional GFR measurements—is driving disease progression. In this respect, a better understanding of renal sodium handling in congestive heart failure is crucial to achieve more tailored decongestive therapy, while preserving renal function.
The effect of thyroid function on clinical outcome in patients with heart failure
Authors: Chen Shmuel , Shauer Ayelet , Zwas Donna R. , Lotan Chaim , Keren Andre , Gotsman Israel
Published: February 2014

Aims

Thyroid dysfunction is known to effect cardiac function and is a risk factor for developing heart failure (HF). Data regarding the clinical significance of thyroid‐stimulating hormone (TSH) levels alone as a predictor of outcome in patients with HF is sparse. We evaluated the significance of TSH on clinical outcome in a large cohort of patients with chronic HF.

Methods and results

Patients with a diagnosis of HF at a Health Maintenance Organization (n = 5599) were followed for cardiac‐related hospitalizations and death. Median TSH levels were 2.2 mIU/L (interquartile range 1.4–3.5). We divided patients into quartiles based on TSH levels. Median follow‐up time was 434 days and the overall mortality rate was 13.2%. Both a high and a low TSH level was associated with an increased mortality rate. Cox regression analysis after adjustment for other significant predictors demonstrated that the highest TSH quartile was associated with increased mortality compared with those with the lowest mortality [second quartile: TSH 1.4–2.2 mIU/L, hazard ratio (HR) 1.36, 95% confidence interval (CI) 1.08–1.71, P = 0.01]. TSH was also an independent predictor of death and cardiac‐related hospitalization. Analysis of patients not on levothyroxine treatment (78%) demonstrated that TSH was an even stronger predictor of mortality (HR 1.54, 95% CI 1.17–2.03, P = 0.002). Additional analysis based on accepted clinical cut‐offs of TSH demonstrated that increasing TSH levels above normal were independently associated with increased mortality and cardiac‐related hospitalizations.

Conclusions

Increased TSH levels are associated with worse clinical outcome in patients with HF. Thyroid imbalance confers significant risk in HF and warrants attention.
Base‐Catalyzed Hydrolysis of a RuII–Chloro–dmso Complex and Its Reactivity towards L‐Methionine
Authors: Brindell Małgorzata , Dyduch Karol , Adamowicz Agnieszka , Urbanowicz Elżbieta , Oszajca Maria , Michalak Artur , Stochel Grażyna , van Eldik Rudi
Published: February 2014

The ruthenium(II) complex cis‐[RuCl2(dmso)4] is known for its antiproliferative properties. This has stimulated the discovery of a wide group of new ruthenium complexes considered as potential anticancer drugs. The stability of these ruthenium complexes under physiological conditions and their interaction with protein amino acid residues are particularly important because of their intravenous administration. The studies presented here are devoted to the stability of cis‐[RuCl2(dmso)4] under physiological pH conditions and its reactivity towards L‐methionine. Immediate dissociation of one dmso ligand from the parent complex after dilution in water leads to the formation of fac‐[RuCl2(H2O)(dmso)3], which under basic conditions undergoes stepwise dissociation of chloride ions without further dmso release. The hydrolysis of fac‐[RuCl2(H2O)(dmso)3] at pH 7.4 and also base‐catalyzed hydrolysis were investigated in detail by application of kinetic and spectroscopic (UV/Vis, NMR) measurements. The combined experimental and theoretical study revealed that L‐methionine coordinates to fac‐[RuCl(OH)(H2O)(dmso)3] by substituting a water ligand with simultaneous dmso release. Detailed NMR characterization of the product indicated that methionine coordinates through the NH2 group rather than the thioether moiety. This conclusion was further supported by theoretical calculations with the application of ETS–NOCV analysis.
Quasi‐Planar Organic Synthon and S···X (X = S or H–C) Contacts in Flat Copper Coordination Chains: Syntheses, Structures and Conductive Behaviour
Authors: Zhu Hai‐Bin , Shan Ru‐Yu , Wu Yan‐Fang , Lou Yong‐Bing
Published: February 2014

A new organic building block, TEPB, has been synthesized that comprises three 2‐ethylthio‐substituted pyrimidine groups coupled to one central phenyl ring at the 1‐, 3‐ and 5‐positions. TEPB exhibits a quasi‐planar conformation due to its intramolecular C–H···N hydrogen bonds. The assembly of TEPB with CuI and CuCl2 produced two flat coordination chains 1 and 2, both exhibiting similar assembly hierarchies from chain through 2D layer to 3D architecture. It was found that extensive S···S and C–H···S contacts exist in the 2D layers of 1 and 2, respectively. Between the 2D layers of 2, there are O–H···Cl hydrogen‐bonding interactions between water molecules and coordinated Cl atoms that provide a proton‐transfer network. Complex 2 exhibits a smaller optical band gap (1.11 eV) than 1 (1.93 eV), which has been attributed to d‐electron transition in the copper(II) ion. The d.c. conductivities of 1 and 2 at room temperature were measured to be 2.84 × 10–12 and 2.42 × 10–10 S cm–1, respectively. The a.c. conductivity of 2 obtained at room temperature by the complex impedance technique is about 5.90 × 10–9 S cm–1, which can be attributed largely to proton conduction. Moreover, the a.c. conductivity of 2 decreases almost linearly with increasing temperature, presumably as a result of its temperature‐sensitive O–H···Cl hydrogen‐bonding network that allows for proton conduction.
Photo‐Oxidation of Water under Ambient Conditions – The Search for Effective Oxygen‐Evolving Catalysts
Authors: Harriman Anthony
Published: February 2014

This essay is based on research leading to the identification of catalysts capable of the selective oxidation of water to molecular oxygen. The real need for such materials relates to the large‐scale photochemical dissociation of water into its constituent elements, as opposed, for example, to the electrochemical decomposition of water at macroscopic electrodes. Combining the catalyst with the essential components needed for efficacious photochemistry brings special challenges, as does the ultimate need to scale up the system by a massive amount. Nature has developed a highly successful process for O2 evolution under ambient illumination that makes use of a cubane tetramanganese cluster having a closely associated calcium cation in attendance. This catalyst is surprisingly delicate and it is debatable as to whether we could adapt such a system for use with artificial photosystems. Historically the latter have used colloidal metal oxides, and consideration is given here as to which materials might offer the most promising catalytic performance. Moving towards heterogeneous systems has more practical meaning, but the same materials come to mind. Recent attention to cobalt‐based catalysts is highlighted as a possible breakthrough that might lead to interesting electrochemical systems when combined with wind turbines. Molecular catalysts provide interesting opportunities for photochemical O2 evolution but suffer from problems of scale‐up. This field has witnessed the most important progress over the past decade or so but still needs urgent attention if advanced materials are to be identified in a timely manner. Finally, consideration is given to the actual status of the field in specific terms of developing an effective artificial photosynthetic apparatus. Moving progressively from using sacrificial redox agents as a simple means to isolate the oxidative photochemical cycle towards full water cleavage will stimulate the development of demonstration models suitable for public display. The reward should be increased investment.
N‐Heterocyclic Dicarbene Iridium(III) Catalysts Enabling Water Oxidation under Visible Light Irradiation
Authors: Volpe Andrea , Sartorel Andrea , Tubaro Cristina , Meneghini Laura , Di Valentin Marilena , Graiff Claudia , Bonchio Marcella
Published: February 2014

Invited for the for the front cover of the Cluster Issue on Water Oxidation Chemistry is the Helios group at the University of Padova, fostering a new research impetus on solar fuels by a collaborative synergy among catalysis, organometallic, mechanistic, and materials science experts. The cover image shows the novel dicarbene iridium(III) complex and oxygen evolution as a result of its catalytic action under visible light irradiation. This is one key goal of the HELIOS strategic project, targeting new molecules and nanomaterials for solar energy schemes, as represented by the fullerene sunflower logo. Dr. Rami Al‐Oweini (ITM‐CNR Postdoctoral Fellow) is acknowledged for his creative design and for putting together the cover illustration.
Cu‐Catalyzed Carbenoid Functionalization of Indoles by Methyl 3,3,3‐Trifluoro‐2‐diazopropionate
Authors: Tsyshchuk Irina E. , Vorobyeva Daria V. , Peregudov Alexander S. , Osipov Sergey N.
Published: February 2014

An efficient protocol for the direct CH‐functionalization of indole and its derivatives has been developed by using Cu(F3‐acac)2‐catalyzed insertion of CF3‐carbene derived from methyl 3,3,3‐trifluoro‐2‐diazopropionate. The reaction proceeds with high regioselectivity within a few minutes under low catalyst loading and allows the introduction of CF3 and carboxylate functions simultaneously into the 3‐ or 2‐position of the indole core. This method can be successfully applied for the synthesis of trifluoromethyl‐containing paullones, which are new members of the known family of potent inhibitors of cyclin‐dependent kinases.
Synthesis of Regioisomeric Pyrido[c]azocanones from Azaindanone Derivatives
Authors: Penning Miriam , Christoffers Jens
Published: February 2014

A ring enlargement reaction with methylamine gave new pyrido[2,3‐c]‐, pyrido[3,4‐c]‐ and pyrido[3,2‐c]azocanone derivatives from cyclic β‐oxo esters with a cyclopentapyridine skeleton and a 1,4‐diketone moiety. The starting materials for this ring transformation were either prepared from halogenopyridine carboxylates by Heck reaction and subsequent hydrogenation, or (halogenomethyl)pyridine carboxylates were submitted to SN reaction with diethyl malonate. Both routes were completed by Dieckmann condensation to build the cyclic β‐oxo ester structure and alkylation with phenacylbromide to install the 1,4‐diketone motif.
Cathodic Stripping Determination of Water in Organic Solvents
Authors: Xiao Changlong , Weremfo Alexander , Wan Chenyang , Zhao Chuan
Published: February 2014

A cathodic stripping voltammetry (CSV) method has been developed to determine water content in organic solvents based on electrooxidation of a gold electrode in the presence of water to form gold oxides upon anodic polarizations. Following cathodic potential scan, a sharp reductive stripping peak of gold oxides is generated and the magnitude of the peak current is related to the water content in the organic solvents. The method has been applied for determination of water in four commonly used water miscible organic solvents, acetonitrile, tetrahydrofuran, acetone and glacial acetic acid, with limits of detection of 60, 10, 40 and 10 ppm, respectively.
A study on NO reduction by biomass tar‐using phenol as a model compound of tar from updraft biomass gasification
Authors: Liu Chun‐yuan , Zhang Chang‐shun , Yin Ren‐hao
Published: February 2014

The character of biomass tar to reduce nitric oxide (NO) under conditions relevant for the reburning process is investigated experimentally. Flow reactor experiments on reduction of NO by phenol, a model compound of tar from updraft biomass gasification, are conducted from fuel lean to rich conditions, covering temperatures of 1173–1573 K and equivalence ratio of 0.34–1.73. Under the oxygen rich conditions, with the temperature increased, the efficiency of NO reduction was first increased which may be caused by the increasing quantity of hydrocarbon and non‐hydrocarbon radicals produced by cracking of phenol. With a further increase in temperature, the thermal crack of phenol was enhanced and less oxygen is needed. The crack products were consumed mostly through reacting with the rich oxygen, and inhibit the NO reduction reactions. Under the fuel rich conditions, the efficiency of NO reduction increased continuously with the temperature because the increased temperature promotes phenol decomposition as well as the reactions of NO reduction by the crack products. NO reduction efficiency decline with the decrease of phenol concentration. The different cracking and polymerization action by phenol and benzene presented the different NO reduction characters of tar. And comparing with other fuels shed light on the effect of tar on NO reduction. © 2014 American Institute of Chemical Engineers Environ Prog, 34: 47–53, 2015
Economic efficiency of different light wavelengths and intensities using LEDs for the cultivation of green microalga Botryococcus braunii (NIES‐836) for biofuel production
Authors: Okumura Chikako , Saffreena Noor , Rahman M. Azizur , Hasegawa Hiroshi , Miki Osamu , Takimoto Akira
Published: February 2014

Microalgae have been regarded as potential and alternative next‐generation renewable energy sources because of high lipid content in their cell. An efficient light source is pre‐requisite for rapid production of microalgae biomass in photobioreactor in order to produce biofuel, and light emitting diodes (LEDs) have recently been identified as effective and low‐cost energy sources for microalgae cultivation. Green microalga Botryococcus braunii has relatively higher lipid content than other microalgae. In the present study, we investigated the effects of various LEDs with different light wavelengths and illumination intensities on the growth of B. braunii (strain NIES‐836) for the first time. High intensity blue LED was found to be the most effective light source for the growth of the microalga. Monochromatic blue and mixed red‐green‐blue LEDs produced the highest biomass (0.22 and 0.39 mg d wt mL−1, respectively) and relative growth rates (9.20 ± 2.16 and 9.47 ± 2.67 μg d wt mL−1 d−1, respectively) of the microalga. The growth efficiency, in terms of biomass production and energy consumption (mg d wt mL−1 w−1), of the microalga was the highest with blue‐green LED (5.07) followed by red‐green‐blue (4.00) and blue (3.91) LEDs. The highest economic efficiency in terms of power cost and biomass production (mg d wt mL−1 $−1) was obtained with blue‐green LED (182.54) followed by red‐green‐blue (144.74), blue (132.00), and blue‐red (125.83) LEDs indicating that these LEDs would be more cost‐effective than other LEDs for large‐scale cultivation of this microalga. © 2014 American Institute of Chemical Engineers Environ Prog, 34: 269–275, 2015
Homonuclear Decoupling of 1H Dipolar Interactions in Solids by means of Heteronuclear Recoupling
Authors: Olsen Gregory L. , Lupulescu Adonis , Dumez Jean‐Nicolas , Emsley Lyndon , Frydman Lucio
Published: February 2014

Line narrowing has been traditionally achieved in solid‐state 1H NMR spectroscopy by applying pulse sequences that combine multiple‐pulse operations with magic‐angle spinning (MAS), to effectively average out the dipoledipole homonuclear Hamiltonian. The present study explores a new alternative that departs from the usual concept of directly acting on the strongly coupled spins with radiofrequency pulses; instead, we seek to achieve a net homonuclear dipolar decoupling in solids by exploring the reintroduction of MAS‐averaged heteronuclear dipolar couplings between the 1H nuclei and directly bonded 13C or 15N nuclei. This recouplinganti‐recoupling (RaR) scheme thus relies on the recoupling of the dipolar interaction with heteronuclear spins, which, under fast MAS, will exceed the strength and will not commute with the homonuclear 1H1H coupling one is intending to average out. Subsequent removal (“antiRecoupling”) of these heteronuclear interactions can lead to narrowed 1H resonances, without ever pulsing on the aforementioned channel. The line‐narrowing properties of RaR are illustrated with numerical simulations and with experiments on model organic solids.
An electronic order set for acute myocardial infarction is associated with improved patient outcomes through better adherence to clinical practice guidelines
Authors: Ballesca Manuel A. , LaGuardia Juan Carlos , Lee Philip C. , Hwang Andrew M. , Park David K. , Gardner Marla N. , Turk Benjamin J. , Kipnis Patricia , Escobar Gabriel J.
Published: February 2014

BACKGROUND

Adherence to evidence‐based recommendations for acute myocardial infarction (AMI) remains unsatisfactory.

OBJECTIVE

Quantifying association between using an electronic AMI order set (AMI‐OS) and hospital processes and outcomes.

DESIGN

Retrospective cohort study.

SETTING

Twenty‐one community hospitals.

PATIENTS

A total of 5879 AMI patients were hospitalized between September 28, 2008 and December 31, 2010.

MEASUREMENTS

We ascertained whether patients were treated using the AMI‐OS or individual orders (a la carte). Dependent process variables were use of evidence‐based care; outcome variables were mortality and rehospitalization.

RESULTS

Use of individual and combined therapies improved outcomes (eg, 50% lower odds of 30‐day mortality for patients with ≥3 therapies). The 3531 patients treated using the AMI‐OS were more likely to receive evidence‐based therapies (eg, 50% received 5 different therapies vs 36% a la carte). These patients had lower 30‐day mortality (5.7% vs 8.5%) than the 2348 treated using a la carte orders. Although AMI‐OS patients' predicted mortality risk was lower (3.2%) than that of a la carte patients (4.8%), the association of improved processes and outcomes with the use of the AMI‐OS persisted after risk adjustment. For example, after inverse probability weighting, the relative risk for inpatient mortality in the AMI‐OS group was 0.67 (95% confidence interval: 0.52‐0.86). Inclusion of use of recommended therapies in risk adjustment eliminated the benefit of the AMI‐OS, highlighting its mediating effect on adherence to evidence‐based treatment.

CONCLUSIONS

Use of an electronic order set is associated with increased adherence to evidence‐based care and better AMI outcomes. Journal of Hospital Medicine 2014;9:155–161. © 2014 Society of Hospital Medicine
Specialties performing paracentesis procedures at university hospitals: Implications for training and certification
Authors: Barsuk Jeffrey H. , Feinglass Joe , Kozmic Sarah E. , Hohmann Samuel F. , Ganger Daniel , Wayne Diane B.
Published: February 2014

BACKGROUND

Paracentesis procedure competency is not required for internal medicine or family medicine board certification, and national data show these procedures are increasingly referred to interventional radiology (IR). However, practice patterns at university hospitals are less clear.

OBJECTIVE

To evaluate which specialties perform paracentesis procedures at university hospitals, compare characteristics of patients within each specialty, and evaluate length of stay (LOS) and hospital costs.

DESIGN, SETTING, PATIENTS

Observational administrative database review of patients with liver disease who underwent paracentesis procedures in hospitals participating in the University HealthSystem Consortium (UHC) Database from January 2010 through December 2012. UHC is an alliance of 120 academic medical centers and their 290 affiliated hospitals.

EXPOSURE

Patients with liver disease who underwent inpatient paracentesis procedures.

MEASUREMENTS

We compared characteristics of patients who underwent paracentesis procedures by physician specialty, modeling the effects of patient characteristics on the likelihood of IR referral. We also analyzed LOS and hospital costs among patients with a >20% predicted probability of IR referral.

RESULTS

There were 97,577 paracentesis procedures performed during 70,862 hospital stays in 204 hospitals. IR performed 29% of paracenteses versus 49% by medicine and medicine subspecialties including gastroenterology/hepatology. Patients who were female, obese, and those with lower severity of illness were more likely to be referred to IR. Patients with a medicine or gastroenterology/hepatology paracentesis had a similar LOS compared to IR. Hospital costs were an estimated as $1308 less for medicine and $803 less for gastroenterology/hepatology compared to admissions with IR procedures (both P = 0.0001).

CONCLUSIONS

Internal medicine‐ and family medicine‐trained clinicians frequently perform paracentesis procedures on complex inpatients but are not currently required to be competent in the procedure. Increasing bedside paracentesis procedures may reduce healthcare costs. Journal of Hospital Medicine 2014;9:162–168. © 2014 Society of Hospital Medicine
Patient, hospital, and geographic disparities associated with comanagement during hospitalization for colorectal cancer surgery
Authors: de Vries Simone , Jeffe Donna B. , Pruitt Sandi L. , Davidson Nicholas O. , Schootman Mario
Published: February 2014

BACKGROUND

Comanagement of surgical patients has increased, but information regarding detailed characteristics of patients receiving comanagement during hospitalization for colorectal cancer (CRC) surgery is lacking.

OBJECTIVE

To examine the use of and characteristics associated with comanagement of patients hospitalized for CRC surgery.

DESIGN

This study used a population‐based cross‐sectional design.

SETTING

We used the linked 2000 to 2005 Surveillance, Epidemiology, and End Results and Medicare claims data.

PATIENTS

We included 37,065 patients aged 66 years or older, hospitalized for definitive CRC surgery following stage I to III diagnosis.

MEASUREMENTS

The outcome of interest was comanagement during hospitalization for CRC surgery, and we examined the association between several patient and hospital characteristics. Comanagement was defined as having a relevant physician (ie, internal medicine hospitalist/generalist) submit a claim for evaluation and management services on 70% or more of the days of hospitalization of the patient.

RESULTS

During hospitalization for CRC surgery, 27.6% of patients were comanaged, but this percentage varied widely across hospitals (from 1.9% to 83.2%). Several patient and hospital characteristics were associated with the use of comanaged care, of which important characteristics included older age at diagnosis, presence of comorbidity, emergency surgery, and hospital volume.

CONCLUSIONS

Extensive variability existed in comanagement use across patients and hospitals, likely reflecting the lack of evidence for its clinical effectiveness. Journal of Hospital Medicine 2014;9:226–231. © 2014 Society of Hospital Medicine
Internal medicine rounding practices and the accreditation council for graduate medical education core competencies
Authors: Shoeb Marwa , Khanna Raman , Fang Margaret , Sharpe Brad , Finn Kathleen , Ranji Sumant , Monash Brad
Published: February 2014

BACKGROUND

The Accreditation Council for Graduate Medical Education (ACGME) has established the requirement for residency programs to assess trainees' competencies in 6 core domains (patient care, medical knowledge, practice‐based learning, interpersonal skills, professionalism, and systems‐based practice). As attending rounds serve as a primary means for educating trainees at academic medical centers, our study aimed to identify current rounding practices and attending physician perceived capacity of different rounding models to promote teaching within the ACGME core competencies.

METHODS

We disseminated a 24‐question survey electronically using educational and hospital medicine leadership mailing lists. We assessed attending physician demographics and the frequency with which they used various rounding models, as defined by the location of the discussion of the patient and care plan: bedside rounds (BR), hallway rounds (HR), and card‐flipping rounds (CFR). Using the ACGME framework, we assessed the perceived educational value of each model.

RESULTS

We received 153 completed surveys from attending physicians representing 34 institutions. HR was used most frequently for both new and established patients (61% and 43%), followed by CFR for established patients (36%) and BR for new patients (22%). Most attending physicians indicated that BR and HR were superior to CFR in promoting the following ACGME competencies: patient care, systems‐based practice, professionalism, and interpersonal skills.

CONCLUSIONS

HR is the most commonly employed rounding model. BR and HR are perceived to be valuable for teaching patient care, systems‐based practice, professionalism, and interpersonal skills. CFR remains prevalent despite its perceived inferiority in promoting teaching across most of the ACGME core competencies. Journal of Hospital Medicine 2014;9:239–243. © 2014 Society of Hospital Medicine
Characterization of multiple fragmentation pathways initiated by collision‐induced dissociation of multifunctional anions formed by deprotonation of 2‐nitrobenzenesulfonylglycine
Authors: Tovstiga Tara E. , Gillis Elizabeth A. L. , Grossert J. Stuart , White Robert L.
Published: February 2014

The correlation of anion structure with the fragmentation behavior of deprotonated nitrobenzenesulfonylamino acids was investigated using tandem mass spectrometry, isotopic labeling and computational methods. Four distinct fragmentation pathways resulting from the collision‐induced dissociation (CID) of deprotonated 2‐nitrobenzenesulfonylglycine (NsGly) were characterized. The unusual loss of the aryl nitro substituent as HONO was the lowest energy process. Subsequent successive losses of CO, HCN and SO2 indicated that an ortho cyclization reaction had accompanied loss of HONO. Other pathways involving rearrangement of the ionized sulfonamide group, dual bond cleavage and intramolecular nucleophilic displacement were proposed to account for the formation of phenoxide, arylsulfinate and arylsulfonamide product ions at higher collision energies. The four distinct fragmentation pathways were consistent with precursor–product relationships established by CID experiments, isotopic labeling results and the formation of analogous product ions from 2,4‐dinitrobenzenesulfonylglycine and the Ns derivatives of alanine and 2‐aminoisobutyric acid. The computations confirmed a low barrier for ortho cyclization with loss of HONO and feasible energetics for each reaction step in the four pathways. Computations also indicated that three of the fragmentation pathways started from NsGly ionized at the carboxyl group. Overall, the pathways identified for the fragmentation of the NsGly anion differed from processes reported for anions containing a single functional group, demonstrating the importance of functional group interactions in the fragmentation pathways of multifunctional anions. Copyright © 2014 John Wiley & Sons, Ltd.
A comprehensive library‐based, automated screening procedure for 46 synthetic cannabinoids in serum employing liquid chromatography‐quadrupole ion trap mass spectrometry with high‐temperature electrospray ionization
Authors: Huppertz Laura M. , Kneisel Stefan , Auwärter Volker , Kempf Jürgen
Published: February 2014

Considering the vast variety of synthetic cannabinoids and herbal mixtures – commonly known as ‘Spice’ or ‘K2’ – on the market and the resulting increase of severe intoxications related to their consumption, there is a need in clinical and forensic toxicology for comprehensive up‐to‐date screening methods. The focus of this project aimed at developing and implementing an automated screening procedure for the detection of synthetic cannabinoids in serum using a liquid chromatography‐ion trap‐MS (LC‐MSn) system and a spectra library‐based approach, currently including 46 synthetic cannabinoids and 8 isotope labelled analogues. In the process of method development, a high‐temperature ESI source (IonBoosterTM, Bruker Daltonik) and its effects on the ionization efficiency of the investigated synthetic cannabinoids were evaluated and compared to a conventional ESI source. Despite their structural diversity, all investigated synthetic cannabinoids benefitted from high‐temperature ionization by showing remarkably higher MS intensities compared to conventional ESI. The employed search algorithm matches retention time, MS and MS2/MS3 spectra. With the utilization of the ionBooster source, limits for the automated detection comparable to cut‐off values of routine MRM methods were achieved for the majority of analytes. Even compounds not identified when using a conventional ESI source were detected using the ionBooster‐source. LODs in serum range from 0.1 ng/ml to 0.5 ng/ml. The use of parent compounds as analytical targets offers the possibility of instantly adding new emerging compounds to the library and immediately applying the updated method to serum samples, allowing the rapid adaptation of the screening method to ongoing forensic or clinical requirements. The presented approach can also be applied to other specimens, such as oral fluid or hair, and herbal mixtures and was successfully applied to authentic serum samples. Quantitative MRM results of samples with analyte concentrations above the determined LOD were confirmed as positive findings by the presented method. Copyright © 2014 John Wiley & Sons, Ltd.
Resonant Raman scattering of graphite intercalation compounds KC8, KC24, and KC36
Authors: Wang Yu , Puech Pascal , Gerber Iann , Pénicaud Alain
Published: February 2014

Graphite intercalation compounds, due to charge transfer between layers of graphite and intercalants, have a strongly shifted Fermi level. Potassium is known to give its electron leading to a large charge transfer fc close to for stage 1 (KC8) and for stage 2 (KC24). The question is more subtle in stage 3 (KC36) for which the graphene layers are not equivalent. For stage 3, two Raman G bands are clearly visible, corresponding to the interior layer and the boundary layers, respectively. By varying the excitation energy from UV to infrared, we observe that the intensity of the boundary layers G band versus that of the interior layer is maximum at 2.5 eV, leading to a sharp resonance profile at room temperature. Using first‐principle calculation, we associate this transition to π → π∗ of the bounding layers. Copyright © 2014 John Wiley & Sons, Ltd.
Conversion from twice daily tacrolimus capsules to once daily extended-release tacrolimus (LCP-Tacro): Phase 2 trial of stable liver transplant recipients
Authors: Alloway Rita R. , Eckhoff Devin E. , Washburn Kenneth W. , Teperman Lewis W.
Published: February 2014

LCP-Tacro is an extended-release formulation of tacrolimus designed for once-daily dosing. Studies in renal transplantation demonstrate greater bioavailability with similar safety and efficacy vs. twice-daily tacrolimus capsules. In this phase 2 study, adult stable liver transplant patients on tacrolimus capsules (Prograf) twice-daily were converted to tacrolimus tablets (LCP-Tacro) once-daily; patients continued on LCP-Tacro once-daily for days 8–21; target trough levels were 5–15 ng/mL; 24-hour pharmacokinetic (PK) assessments were done on days 7 (baseline pre-switch), 14, and 21. A 6 month extension study phase evaluated PK and safety following a total of 52 weeks of LCP-Tacro. Fifty-seven patients completed LCP-Tacro dosing in the core study; 43 completed the extension phase. The mean conversion ratio was 0.71 (Prograf:LCP-Tacro). PK data demonstrated consistent exposure (AUC) at the lower conversion dose. Cmax, Cmax/Cmin ratio, percent fluctuation and swing were significantly (P<0.001) lower and Tmax significantly (P<0.001) longer for LCP-Tacro vs. Prograf. AUC24 and Cmin correlation coefficients after 7 and 14 days of therapy were ≥0.93. There were no significant differences in PK parameters at week 26 vs. 14. One patient experienced an unrelated serious adverse event (SAE) during the core study and discontinued. There were six unrelated SAEs in the extension and 1 possibly related (rejection) that resolved; there were 3 discontinuations due to AEs during the extension. In this study, patients were safely converted from Prograf twice-daily to LCP-Tacro. The greater bioavailability of LCP-Tacro allowed for once-daily dosing and similar (AUC) exposure at a dose approximately 30% less than the total daily dose of Prograf. LCP-Tacro displayed significantly lower peak and peak-trough fluctuations. LCP-Tacro administered over one year was well tolerated with no new safety concerns. Liver Transpl 20:564–575, 2014. © 2014 AASLD.
Impact of pretransplant rifaximin therapy on early post–liver transplant infections
Authors: Esfeh Jamak Modaresi , Hanouneh Ibrahim A. , Koval Christine E. , Kovacs Christopher , Dalal Deepan S. , Ansari-Gilani Kianoush , Confer Bradley D. , Eghtesad Bijan , Zein Nizar N. , Menon Narayanan K. V.
Published: February 2014

Bacterial and fungal infections are major causes of morbidity and mortality after liver transplantation (LT). The role of intestinal decontamination in the prevention of post-LT infections is controversial. Rifaximin is widely used for the treatment of hepatic encephalopathy. The effect of rifaximin on post-LT infections is unknown. The aim of our study was to determine the effect of rifaximin therapy in the pretransplant period on early bacterial infections (EBIs) and fungal infections within the first 30 days after LT. All adult patients who underwent LT at our institution (January 2009 to July 2011) were included in this retrospective cohort study. Patients receiving antibiotics other than pretransplant protocol antibiotics were excluded. Patients were stratified into 2 groups based on the presence or absence of rifaximin therapy for at least 2 days before LT. Infections were defined by the isolation of any bacterial or fungal organisms within 30 days of LT. Multivariate regression analysis, Student t tests, and Pearson's chi-square tests were used to compare the 2 groups. Two hundred sixty-eight patients were included, and 71 of these patients (26.5%) were on rifaximin at the time of LT. The 2 groups were comparable with respect to age, sex, race, and Model for End-Stage Liver Disease score. There were no significant differences in the rates of EBIs (30% for the non-rifaximin group and 25% for the rifaximin group, P = 0.48) or fungal infections between the 2 groups. There was no increase in antimicrobial resistance among the infecting organisms. There was no difference in survival between the rifaximin and non-rifaximin groups (98% versus 97%, P = 0.36). In conclusion, the use of rifaximin in the pre-LT period was not associated with an increased risk of bacterial or fungal infections in the early post-LT period. Liver Transpl 20:544–551, 2014. © 2014 AASLD.
Bland embolization versus chemoembolization of hepatocellular carcinoma before transplantation
Authors: Kluger Michael D. , Halazun Karim J. , Barroso Ryan T. , Fox Alyson N. , Olsen Sonja K. , Madoff David C. , Siegel Abby B. , Weintraub Joshua L. , Sussman Jonathan , Brown Robert S. , Cherqui Daniel , Emond Jean C.
Published: February 2014

There is conflicting literature regarding the superiority of transarterial chemoembolization (TACE) versus bland transarterial embolization (TAE), and this has not been well studied before transplantation. Twenty-five TAE patients were matched in a 1:2 ratio with TACE patients by the initial radiographic tumor size and number in a retrospective, case-controlled study. The patients were otherwise treated according to the same protocols. The method of embolization was chosen on the basis of interventionalist practices at 2 sites within the program. Kaplan-Meier survival analyses at 1 and 3 years were the primary endpoints. There were no significant demographic differences between the groups. The mean adjusted Model for End-Stage Liver Disease scores at transplantation and waiting times were not significantly different between the TAE and TACE patients (MELD scores: 26 ± 3 versus 24 ± 3 points, P = 0.12; waiting times: 13 ± 8 versus 11 ± 10 months, P = 0.43). TAE patients (16%) were less likely than TACE patients (40%) to require 2 procedures (P = 0.04). Explant tumors were completely necrotic for 36% of the TAE patients and for 26% of the TACE patients. The 3-year overall survival rates were 78% for the TAE patients and 74% for the TACE patients (P = 0.66), and the 3-year recurrence-free survival rates were 72% for the TAE patients and 68% for the TACE patients (P = 0.67). On an intention-to-treat basis, there was no significant risk of wait-list dropout associated with TAE or TACE (P = 0.83). In conclusion, there were no significant differences in wait-list dropout or in overall or recurrence-free survival between HCC patients undergoing TAE and HCC patients undergoing TACE before transplantation. Liver Transpl 20:536–543, 2014. © 2014 AASLD.
Analysis of μM, D‐orthogonal exponentials for the planar four‐element digit sets
Authors: Li Jian‐Lin
Published: February 2014

The self‐affine measure is a unique probability measure satisfying the self‐affine identity with equal weight. It only depends upon an expanding matrix M and a finite digit set D. In this paper we study the question of when the ‐space has infinite families of orthogonal exponentials. Such research is necessary to further understanding the spectrality of . For a class of planar four‐element digit sets, we present several methods to deal with this question. The application of each method is also given, which extends the known results in a simple manner.
Pharmacophore Mapping, In Silico Screening and Molecular Docking to Identify Selective Trypanosoma brucei Pteridine Reductase Inhibitors
Authors: Dube Divya , Sharma Sujata , Singh Tej P. , Kaur Punit
Published: February 2014

Trypanosoma brucei Pteridine reductase (TbPTR1) is of vital importance and is an established drug target for dreaded Human African trypanosomiasis (HAT). Pharmacophore perception strategy has been employed to identify key chemical features responsible for the biological activity for TbPTR1. The findings suggest that three different pharmacophore features can be associated with T. brucei anti‐PTR1 activity namely: H‐bond donors (D), Hydrophobic aromatic (H) and Ring aromatic (R). The resulting hypothesis is able to predict the activity of other existing TbPTR1 inhibitors with a correlation coefficient (r) of 0.89. An in silico database screening, based on the best hypothesis, has been used to identify some potential nanomolar range TbPTR1 inhibitors. These compounds were then checked by molecular docking and subjected to ADMET analysis. Further, a detailed comparison of the pharmacophore behavior and differential analysis of binding pockets of T. brucei and L. major was made which revealed subtle differences in terms of their shape and charge properties. This investigation can form the basis for tweaking the specificity of compounds for generating new improved species specific inhibitor molecules for Pteridine reductase in these different parasitic protozoans.
Development of a New Decision Tree to Rapidly Screen Chemical Estrogenic Activities of Xenopus laevis
Authors: Wang Ting , Li Weiying , Zheng Xiaofeng , Lin Zhifen , Kong Deyang
Published: February 2014

During the last past decades, there is an increasing number of studies about estrogenic activities of the environmental pollutants on amphibians and many determination methods have been proposed. However, these determination methods are time‐consuming and expensive, and a rapid and simple method to screen and test the chemicals for estrogenic activities to amphibians is therefore imperative. Herein is proposed a new decision tree formulated not only with physicochemical parameters but also a biological parameter that was successfully used to screen estrogenic activities of the chemicals on amphibians. The biological parameter, CDOCKER interaction energy (Ebinding) between chemicals and the target proteins was calculated based on the method of molecular docking, and it was used to revise the decision tree formulated by Hong only with physicochemical parameters for screening estrogenic activity of chemicals in rat. According to the correlation between Ebinding of rat and Xenopus laevis, a new decision tree for estrogenic activities in Xenopus laevis is finally proposed. Then it was validated by using the randomly 8 chemicals which can be frequently exposed to Xenopus laevis, and the agreement between the results from the new decision tree and the ones from experiments is generally satisfactory. Consequently, the new decision tree can be used to screen the estrogenic activities of the chemicals, and combinational use of the Ebinding and classical physicochemical parameters can greatly improves Hong’s decision tree.
Scheduling twin robots on a line
Authors: Erdoğan Güneş , Battarra Maria , Laporte Gilbert
Published: February 2014

This article introduces the twin robots scheduling problem (TRSP), in which two robots positioned at the opposite ends of a rail are required to deliver items to positions along the rail, and the objective is to minimize the makespan. A proof of ‐hardness of the TRSP is presented, along with exact and heuristic algorithms. Computational results on challenging instances are provided.Copyright © 2014 Wiley Periodicals, Inc. Naval Research Logistics 61: 119–130, 2014
Assessing the availability of the teratogenic drug isotretinoin outside the pregnancy prevention programme: a survey of e‐pharmacies
Authors: Lagan Briege M. , Dolk Helen , White Bronagh , Uges Donald R. A. , Sinclair M.
Published: February 2014

Purpose

The increase in online purchasing of medications raises safety concerns regarding teratogenic drugs. The use of the teratogenic drug ‘isotretinoin’ for women of childbearing age requires strict adherence to the Pregnancy Prevention Programme (PPP), a risk minimisation measure imposed on prescribers and users. We sought to determine how readily consumers can purchase isotretinoin online and the associated safety procedures and information.

Methods

A descriptive cross‐sectional survey was conducted of 50 e‐pharmacies identified from commonly used search engines. E‐pharmacy characteristics and isotretinoin PPP specific criteria were evaluated. Purchases of isotretinoin from seven e‐pharmacies not bearing authentication logos and not requiring a prescription were assessed for PPP policy adherence, purchasing procedures and compound quality.

Results

Forty‐three (86%) of the e‐pharmacies did not have an authentication seal/logo. Isotretinoin could be purchased from 42 sites without a valid prescription. Information on isotretinoin causing birth defects was lacking in 25 of the 50 sites, on not taking isotretinoin in pregnancy in 24 sites and not taking isotretinoin if planning or at risk of a pregnancy in 33 sites. Of the eight attempted purchases, seven arrived, all without any patient information leaflet. All were verified as isotretinoin.

Conclusion

The Internet provides a loophole for purchasing of medications known to cause congenital abnormalities, which needs to be addressed by medicines regulatory agencies worldwide. The current PPP for isotretinoin may be failing to protect mothers and babies from preventable harm—clinicians need to be aware of this, and the public needs to be educated about the potential risks. © 2014 The Authors. Pharmacoepidemiology and Drug Safety published by John Wiley & Sons, Ltd.