bluuebunny/crossref_metadata_2025 huggingface dataset:
ChemInform Abstract: Flexible and Practical Synthesis of Anthracenes Through Gold‐Catalyzed Cyclization of o‐Alkynyldiarylmethanes.
Authors: Shu Chao , Chen Cheng‐Bin , Chen Wei‐Xi , Ye Long‐Wu
Published: February 2014

Notable features of this novel gold‐catalyzed hydroarylation process include tolerance of a wide range of functional groups, mild reaction conditions, simple procedure, and no need to avoid moisture or air.
ChemInform Abstract: Rhodium(III)‐Amine Dual Catalysis for the Oxidative Coupling of Aldehydes by Directed C—H Activation: Synthesis of Phthalides.
Authors: Tan Peng Wen , Juwaini Nur Asyikin Binte , Seayad Jayasree
Published: February 2014

The proposed reaction mechanism includes an initial ortho C—H activation followed by insertion and a final annulation step.
ChemInform Abstract: Asymmetric Synthesis of C2‐Symmetric Axially Chiral Biaryls Through Rhodium‐Catalyzed and Alkyne‐Controlled Diastereoselective Double [2 + 2 + 2] Cycloaddition.
Authors: Mori Ayaka , Araki Tatsuya , Miyauchi Yuta , Noguchi Keiichi , Tanaka Ken
Published: February 2014

Significant amounts (20‐45% NMR) of undesired regioisomers are also generated in some cases.
ChemInform Abstract: Recyclable Cinchona Alkaloid Catalyzed Asymmetric Michael Addition Reaction.
Authors: Huang Xin , Yi Wen‐Bin , Ahad Danash , Zhang Wei
Published: February 2014

The applied catalyst can be recovered by fluorous solid‐phase extraction and reused for at least two cycles.
ChemInform Abstract: Gold‐Catalyzed Intramolecular Cyclization of Alkynones with Pyridine Anhydrobases.
Authors: Pawar Lokesh , Pigge F. Christopher
Published: February 2014

Acylation of alkynone substrates followed by benzylic deprotonation produces anhydrobase intermediates which undergo endo‐dig cyclization to afford pyridyl substituted γ‐ and δ‐lactams.
ChemInform Abstract: Stereoselective Synthesis of 2,3‐Dihydropyrroles from Terminal Alkynes, Azides, and α,β‐Unsaturated Aldehydes via N‐Sulfonyl‐1,2,3‐triazoles.
Authors: Miura Tomoya , Tanaka Takamasa , Hiraga Kentaro , Stewart Scott G. , Murakami Masahiro
Published: February 2014

The N‐sulfonyl‐1,2,3‐triazoles [(I), (XI), and (XIII)] are prepared from terminal alkynes and azides by using a known procedure.
ChemInform Abstract: Asymmetric Organocatalytic Michael Addition of Pyrroles to Enones by Cinchona Alkaloid‐Derived Primary Amines.
Authors: Hack Daniel , Enders Dieter
Published: February 2014

A series of the title organocatalysts is screened for the enantioselective Michael addition of pyrroles to enones.
ChemInform Abstract: Transition‐Metal‐Catalyzed Regioselective Alkylation of Indoles with Alcohols.
Authors: Putra Anggi Eka , Takigawa Kei , Tanaka Hatsuki , Ito Yoshihiko , Oe Yohei , Ohta Tetsuo
Published: February 2014

Two sets of reaction conditions using Pd/C or RuCl2(PPh3)2/DPEphos as catalysts are developed for the C3‐alkylation of indoles with a variety of alcohols.
ChemInform Abstract: Nickel‐Catalyzed Decarbonylative Alkylidenation of Phthalimides with Trimethylsilyl‐Substituted Alkynes.
Authors: Shiba Takahiro , Kurahashi Takuya , Matsubara Seijiro
Published: February 2014

Both trimethylsilyl‐substituted alkynes and MAD are essential for the unusual transformation (decarbonylation/alkylidenation) with high selectivities.
ChemInform Abstract: Enantioselective Michael Addition of 1,3‐Diketones to Arenesulfonylalkylindoles: A Flexible Gateway to Optically Active 3‐sec‐Alkyl‐Substituted Indoles Containing a Pyrazole Skeleton.
Authors: Zuo Zongle , Zhang Shilu , Wang Rongming , He Wujun , Wu Song , Xie Xiaohua , Qin Dabin , Jing Linhai
Published: February 2014

Alkylidene indolenines generated in situ from substrates (I) undergo enantioselective Michael addition with 1,3‐diketones.
ChemInform Abstract: Copper(I) Acetate‐Catalyzed Cycloaddition Between Azomethine Imines and Propiolates under Additive‐Free Conditions.
Authors: Shao Changwei , Zhang Qun , Cheng Guolin , Cheng Chuanjie , Wang Xinyan , Hu Yuefei
Published: February 2014

A novel Cu(I)‐acetate catalyzed cycloaddition of azomethine imines (I) with activated terminal alkynes is described to give excellent yields of pyrazolo[1,2‐a]pyrazoles (III).
ChemInform Abstract: Facile Diastereoselective Synthesis of Functionally Enriched Hydantoins via Base‐Promoted Intramolecular Amidolysis of C‐3 Functionalized Azetidin‐2‐ones.
Authors: Mehra Vishu , Kumar Vipan
Published: February 2014

The reaction can also be conducted in the presence of DBU or KOtBu.
ChemInform Abstract: Unusual Mode of Reactivity of 2‐Alkylidene‐4‐oxothiazolidine S‐Oxides under the Pummerer Reaction Conditions.
Authors: Dzambaski Zdravko , Toljic Dorde , Bondzic Bojan , Markovic Rade , Baranac‐Stojanovic Marija
Published: February 2014

The reactivity of 2‐alkylidene‐4‐oxothiazolidine S‐oxides under Pummerer reaction conditions, using SOCl2, SOBr2, or Ac2O as initiators, is examined.
ChemInform Abstract: Ascorbic Acid Based Ionic Liquids: Recyclable and Efficient Catalytic Systems for the Huisgen Cycloaddition.
Authors: Koguchi Shinichi , Nakamura Kaori
Published: February 2014

The use of an ascorbic acid based ionic liquid as catalyst in combination with CuSO4 for the regioselective 1,3‐dipolar cycloaddition of organic azides to terminal alkynes is described.
ChemInform Abstract: A Green Approach for the Synthesis of Biologically Active Heterocyclic Compounds at the Platinum Electrode.
Authors: Kumar Sanjeev , Srivastava H. N.
Published: February 2014

All new 2‐aminooxadiazole derivatives (III) (13 examples) exhibit significant antibacterial and antifungal activities.
ChemInform Abstract: Eco‐Friendly Synthesis of Tetrahydrobenzo[c]xanthenes Catalyzed by Functional Ionic Liquid in Water.
Authors: Yang Jiaojiao , Yang Jinming , Zhu Ting , Wang Pingping , Fang Dong
Published: February 2014

A facile, environmentally benign synthesis of benzoxanthene derivatives (IV) and (VII) via a one‐pot multicomponent reaction of α‐naphthol, aromatic aldehydes and cyclic 1,3‐dicarbonyl compounds is developed.
ChemInform Abstract: Efficient, Stereodivergent Access to 3‐Piperidinols by Traceless P(OEt)3 Cyclodehydration.
Authors: Huy Peter H. , Koskinen Ari M. P.
Published: February 2014

Stereoselective routes towards both isomers of 2‐substituted 3‐piperidinols are developed, exploiting the I2/P(O—Et)3‐cyclodehydration for synthesis of cis‐piperidinols (II).
ChemInform Abstract: Enantioselective Synthesis of N‐Heterocycles via Intramolecular Pd(0)‐Catalyzed Allylic Amination.
Authors: Olszewska Beata , Kryczka Boguslaw , Zawisza Anna
Published: February 2014

The racemic and chiral synthesis of 2‐vinylpyrrolidines and 2‐vinylpiperidines under the employment of several chiral phosphorous ligands with moderate to good enantioselectivities is presented.
ChemInform Abstract: Pinacol Rearrangement of 3,4‐Dihydro‐3,4‐dihydroxyquinolin‐2(1H)‐ones: An Alternative Pathway to Viridicatin Alkaloids and Their Analogues.
Authors: Rudolf Ondrej , Rouchal Michal , Lycka Antonin , Klasek Antonin
Published: February 2014

cis‐3,4‐Dihydroxyquinolin‐2‐ones (II) are subjected to the pinacol rearrangement, resulting in 4‐substituted 3‐hydroxyquinolin‐2‐ones (III).
ChemInform Abstract: Aerobic Multicomponent Tandem Synthesis of 3‐Sulfenylimidazo[1,2‐a]pyridines from Ketones, 2‐Aminopyridines, and Disulfides.
Authors: Ge Wenlei , Zhu Xun , Wei Yunyang
Published: February 2014

This protocol is also amenable to the preparation of 3‐selenated imidazopyridines and works even without the presence of a disulfide or diselenide giving high flexibility of the substituent in 3‐position.
ChemInform Abstract: One‐Pot Synthesis of 4‐Substituted 1H‐[1,2,3]Triazolo[4,5‐c]quinolines Through CuO‐Promoted Tandem Cyclization Reactions of (E)‐3‐(2‐Bromoaryl)‐1‐arylprop‐2‐en‐1‐ones with Sodium Azide.
Authors: Li Kangning , Chen Jinying , Li Jihui , Chen Yongxin , Qu Jinpeng , Guo Xin , Chen Chunxia , Chen Baohua
Published: February 2014

Copper‐promoted tandem cyclization of 2‐bromoarylenones of type (I) with sodium azide offers a direct synthesis of triazoloquinolines (II).
ChemInform Abstract: Tandem Cyclization of a Bispyridinium Chloride: Facile Synthesis of Substituted Indolizines.
Authors: Costa Marta , Noro Jennifer , Brito Alexandra , Proenca Fernanda
Published: February 2014

The obtained title compounds can be easily further functionalized, e.g. via formylation or bromination.
ChemInform Abstract: An Efficient Ionic Liquid Mediated Synthesis of Substituted 5H[1,3]‐Thiazolo[2,3‐b]quinazoline‐3,5‐(2H)‐dione and 5H‐Thiazolo[2,3‐b]quinazolin‐5‐one.
Authors: Yadav Ashok K. , Dhakad Pankaj , Sharma Gopi Ram
Published: February 2014

The reaction is conducted under environmentally benign conditions.
ChemInform Abstract: A Convenient and Efficient Synthesis of Dipeptidyl Benzoxaboroles and Their Peptidomimetics.
Authors: Fu Zhengyan , He Jiangpeng , Tong Aiping , Xie Yongmei , Wei Yuquan
Published: February 2014

Peptide couplings of benzoxaborole are achieved with need for protecting groups to afford dipeptidyl benzoxaboroles (III).
ChemInform Abstract: Palladium‐Catalyzed Direct C‐3 Oxidative Alkenylation of Phosphachromones.
Authors: Kang Dongjin , Cho Jaeyoung , Lee Phil Ho
Published: February 2014

C‐3 alkenylated phosphachromones (III) are synthesized using a direct C‐3 alkenylation with activated and non‐activated alkenes (II) through C—H activation under aerobic conditions.
ChemInform Abstract: Synthesis and Reactions of the Optically Active Selenols Derived from Monoterpenes.
Authors: Scianowski Jacek , Rafalski Jaroslaw , Banach Anna , Czaplewska Justyna , Komoszynska Anna
Published: February 2014

Convenient procedures are described to synthesize optically active selenols derived from monoterpenes.
ChemInform Abstract: 2‐[(Acetyloxy)methyl]‐4‐(acetylsulfanyl)‐2‐(ethoxycarbonyl)‐3‐oxobutyl Group: A Thermolabile Protecting Group for Phosphodiesters.
Authors: Kiuru Emilia , Loennberg Harri , Ora Mikko
Published: February 2014

The potential of the protecting group in compound (IV) as an esterase‐ and thermolabile group is studied.
ChemInform Abstract: Two New Flavonoids from Ageratum conyzoides
Authors: Munikishore Rachakunta , Padmaja Adivireddy , Gunasekar Duvvuru , Blond Alain , Bodo Bernard
Published: February 2014

isolation and structure determination
ChemInform Abstract: Structures and Absolute Configurations of Penicillactones A—C from an Endophytic Microorganism, Penicillium dangeardii Pitt.
Authors: Yu Shishan , et al. et al.
Published: February 2014

Compounds II and III show inhibition of the release of β‐glucuronidase from polymorphonuclear leukocytes.
ChemInform Abstract: Sphenostylisins A—K: Bioactive Modified Isoflavonoid Constituents of the Root Bark of Sphenostylis marginata ssp. erecta.
Authors: Kinghorn A. Douglas , et al. et al.
Published: February 2014

Sphenostylisins A‐C (I), (II), and (III) are isolated from the title root bark together with eight additional new compounds (not shown).
ChemInform Abstract: Pushing Nanoionics to the Limits: Charge Carrier Chemistry in Extremely Small Systems
Authors: Maier Joachim
Published: February 2014

Review: 103 refs.
ChemInform Abstract: Strong‐Disorder Magnetic Quantum Phase Transitions: Status and New Developments
Authors: Vojta Thomas
Published: February 2014

Review: 52 refs.
ChemInform Abstract: Recent Advances in Catalytic Asymmetric Decarboxylative Addition Reactions
Authors: Wang Zu‐Li
Published: February 2014

Review: [43 refs.]
ChemInform Abstract: New Endeavors in Gold Catalysis—Size Matters
Authors: Gramage‐Doria Rafael , Reek Joost N. H.
Published: February 2014

Review: 36 refs.
ChemInform Abstract: Opening an Aladdin′s Cave: The Suzuki Coupling in a Room‐Temperature Ionic Liquid
Authors: Leadbeater Nicholas E.
Published: February 2014

Review: 30 refs.
ChemInform Abstract: New Lignans and Their Biological Activities
Authors: Zhang Jia , Chen Jiejun , Liang Zizhen , Zhao Changqi
Published: February 2014

Review: 144 refs.
ChemInform Abstract: Pillararene‐Based Assemblies: Design Principle, Preparation and Applications
Authors: Zhang Huacheng , Zhao Yanli
Published: February 2014

Review: 109 refs.
ChemInform Abstract: Copper(I)‐Catalyzed Boron Addition Reactions of Alkynes with Diboron Reagents
Authors: Yun Jaesook
Published: February 2014

Review: 26 refs.
ChemInform Abstract: Reactive Iron Carbonyl Reagents for Conversion of Alkynes to Cyclobutenediones, Cyclic Imides and Anhydrides via Double Carbonylation
Authors: Beesu Mallesh , Periasamy Mariappan
Published: February 2014

Review: 72 refs.
ChemInform Abstract: Continuous Process Technology: A Tool for Sustainable Production
Authors: Wiles Charlotte , Watts Paul
Published: February 2014

Review: 58 refs.
ChemInform Abstract: Oxime Ligation: A Chemoselective Click‐Type Reaction for Accessing Multifunctional Biomolecular Constructs
Authors: Ulrich Sebastien , Boturyn Didier , Marra Alberto , Renaudet Olivier , Dumy Pascal
Published: February 2014

Review: 73 refs.
ChemInform Abstract: A Review on Sources, Toxicity and Remediation Technologies for Removing Arsenic from Drinking Water
Authors: Basu Ankita , Saha Debabrata , Saha Rumpa , Ghosh Tuhin , Saha Bidyut
Published: February 2014

Review: 300 refs.
ChemInform Abstract: Low‐Temperature Gasification of Biomass and Lignite: Consideration of Key Thermochemical Phenomena, Rearrangement of Reactions, and Reactor Configuration
Authors: Hayashi Jun‐ichiro , Kudo Shinji , Kim Hyun‐Seok , Norinaga Koyo , Matsuoka Koichi , Hosokai Sou
Published: February 2014

Review: 179 refs.
ChemInform Abstract: Porous Inorganic Nanostructures with Colloidal Dimensions: Synthesis and Applications in Electrochemical Energy Devices
Authors: Tartaj Pedro , Amarilla Jose M.
Published: February 2014

Review: 119 refs.
ChemInform Abstract: New NMR Tools for Characterizing the Dynamic Conformations and Interactions of Oligosaccharides
Authors: Zhang Ying , Yamaguchi Takumi , Kato Koichi
Published: February 2014

Review: 36 refs.
Association between hypogonadism, symptom burden, and survival in male patients with advanced cancer
Authors: Dev Rony , Hui David , Del Fabbro Egidio , Delgado‐Guay Marvin O. , Sobti Nikhil , Dalal Shalini , Bruera Eduardo
Published: February 2014

BACKGROUND

A high frequency of hypogonadism has been reported in male patients with advanced cancer. The current study was performed to evaluate the association between low testosterone levels, symptom burden, and survival in male patients with cancer.

METHODS

Of 131 consecutive male patients with cancer, 119 (91%) had an endocrine evaluation of total (TT), free (FT), and bioavailable testosterone (BT); high‐sensitivity C‐reactive protein (CRP); vitamin B12; thyroid‐stimulating hormone; 25‐hydroxy vitamin D; and cortisol levels when presenting with symptoms of fatigue and/or anorexia‐cachexia. Symptoms were evaluated by the Edmonton Symptom Assessment Scale. The authors examined the correlation using the Spearman test and survival with the log‐rank test and Cox regression analysis.

RESULTS

The median age of the patients was 64 years; the majority of patients were white (85 patients; 71%). The median TT level was 209 ng/dL (normal: ≥ 200 ng/dL), the median FT was 4.4 ng/dL (normal: ≥ 9 ng/dL), and the median BT was 22.0 ng/dL (normal: ≥ 61 ng/dL). Low TT, FT, and BT values were all associated with worse fatigue (P ≤ .04), poor Eastern Cooperative Oncology Group performance status (P ≤ .05), weight loss (P ≤ .01), and opioid use (P ≤ .005). Low TT and FT were associated with increased anxiety (P ≤ .04), a decreased feeling of well‐being (P ≤ .04), and increased dyspnea (P ≤ .05), whereas low BT was only found to be associated with anorexia (P = .05). Decreased TT, FT, and BT values were all found to be significantly associated with elevated CRP and low albumin and hemoglobin. On multivariate analysis, decreased survival was associated with low TT (hazards ratio [HR], 1.66; P = .034), declining Eastern Cooperative Oncology Group performance status (HR, 1.55; P = .004), high CRP (HR, 3.28; P < .001), and decreased albumin (HR, 2.52; P < .001).

CONCLUSIONS

In male patients with cancer, low testosterone levels were associated with systemic inflammation, weight loss, increased symptom burden, and decreased survival.

A high frequency of hypogonadism has been reported in male patients with advanced cancer. In the current study, an increased symptom burden, systemic inflammation, weight loss, opioid use, and poor survival were found to be associated with decreased testosterone levels in male patients with cancer. Cancer 2014;120:1586–1593. © 2014 American Cancer Society.
Ipilimumab before BRAF inhibitor treatment may be more beneficial than vice versa for the majority of patients with advanced melanoma
Authors: Ascierto Paolo A. , Margolin Kim
Published: February 2014

The use of sequential therapy with ipilimumab and vemurafenib reported by Ackerman et al in this issue demonstrates that patients who failed BRAF inhibitor therapy appeared to have an inferior outcome than patients who received ipilimumab followed by BRAF inhibitor therapy. These results are in line with previous experience and provide additional evidence to support the use of ipilimumab before a BRAF inhibitor in the majority of patients with advanced melanoma who have an activating BRAF mutation and who are treated outside of a clinical trial.
Comparative analysis of 5 lung cancer natural history and screening models that reproduce outcomes of the NLST and PLCO trials
Authors: Meza Rafael , ten Haaf Kevin , Kong Chung Yin , Erdogan Ayca , Black William C. , Tammemagi Martin C. , Choi Sung Eun , Jeon Jihyoun , Han Summer S. , Munshi Vidit , van Rosmalen Joost , Pinsky Paul , McMahon Pamela M. , de Koning Harry J. , Feuer Eric J. , Hazelton William D. , Plevritis Sylvia K.
Published: February 2014

BACKGROUND

The National Lung Screening Trial (NLST) demonstrated that low‐dose computed tomography screening is an effective way of reducing lung cancer (LC) mortality. However, optimal screening strategies have not been determined to date and it is uncertain whether lighter smokers than those examined in the NLST may also benefit from screening. To address these questions, it is necessary to first develop LC natural history models that can reproduce NLST outcomes and simulate screening programs at the population level.

METHODS

Five independent LC screening models were developed using common inputs and calibration targets derived from the NLST and the Prostate, Lung, Colorectal and Ovarian Cancer Screening Trial (PLCO). Imputation of missing information regarding smoking, histology, and stage of disease for a small percentage of individuals and diagnosed LCs in both trials was performed. Models were calibrated to LC incidence, mortality, or both outcomes simultaneously.

RESULTS

Initially, all models were calibrated to the NLST and validated against PLCO. Models were found to validate well against individuals in PLCO who would have been eligible for the NLST. However, all models required further calibration to PLCO to adequately capture LC outcomes in PLCO never‐smokers and light smokers. Final versions of all models produced incidence and mortality outcomes in the presence and absence of screening that were consistent with both trials.

CONCLUSIONS

The authors developed 5 distinct LC screening simulation models based on the evidence in the NLST and PLCO. The results of their analyses demonstrated that the NLST and PLCO have produced consistent results. The resulting models can be important tools to generate additional evidence to determine the effectiveness of lung cancer screening strategies using low‐dose computed tomography. Cancer 2014;120:1713–1724. © 2014 American Cancer Society.
Cryptanalysis of smart‐card‐based password authenticated key agreement protocol for session initiation protocol of Zhang et al.
Authors: Jiang Qi , Ma Jianfeng , Tian Youliang
Published: February 2014

As the core signaling protocol for multimedia services, such as voice over internet protocol, the session initiation protocol (SIP) is receiving much attention and its security is becoming increasingly important. It is critical to develop a roust user authentication protocol for SIP. The original authentication protocol is not strong enough to provide acceptable security level, and a number of authentication protocols have been proposed to strengthen the security. Recently, Zhang et al. proposed an efficient and flexible smart‐card‐based password authenticated key agreement protocol for SIP. They claimed that the protocol enjoys many unique properties and can withstand various attacks. However, we demonstrate that the scheme by Zhang et al. is insecure against the malicious insider impersonation attack. Specifically, a malicious user can impersonate other users registered with the same server. We also proposed an effective fix to remedy the flaw, which remedies the security flaw without sacrificing the efficiency. The lesson learned is that the authenticators must be closely coupled with the identity, and we should prevent the identity from being separated from the authenticators in the future design of two‐factor authentication protocols. Copyright © 2014 John Wiley & Sons, Ltd.
Incident heart failure in relation to vascular disease: Insights from the Health, Aging, and Body Composition Study
Authors: Khan Hassan , Kalogeropoulos Andreas P. , Zannad Faiez , Marti Catherine N. , Wilson Peter W.F. , Georgiopoulou Vasiliki V. , Kanaya Alka M. , Newman Anne B. , Schelbert Erik , Harris Tamara B. , Kritchevsky Stephen , Yancy Clyde , Gheorghiade Mihai , Fonarow Gregg C. , Butler Javed ,   for the Health ABC Study
Published: February 2014

Aims

The contribution of heart failure (HF) unrelated to vascular disease to the overall HF burden in older adults is not well characterized. This was investigated in this study.

Methods and results

We assessed HF incidence and outcomes in 2895 participants of the Health ABC Study (age 74 ± 3 years, 48.4% men, 41.4% black) in relation to vascular disease (coronary, peripheral, or cerebrovascular disease) either present at baseline or developed prior to HF. During 11.4 years follow‐up, 493 participants developed HF; 134 (27.2%) in participants without any prior vascular disease and 177 (36.8%) without coronary disease. Both baseline [hazard ratio (HR) 2.4, 95% confidence interval (CI) 1.9–2.8] and incident vascular disease (HR 4.3, 95% CI 3.6–5.2) were associated with HF. During a median follow‐up of 2.1 years after HF onset, 67.5% participants died. Annual mortality after HF development was 21.3% in those with compared with 24.6% in those without vascular disease (HR 1.11, 95% CI 0.87–1.43; P = 0.399). There were 658 all‐cause (436.3/1000 person‐years) and 523 HF‐related (346.4/1000 person‐years) hospitalizations after HF development. There was no significant difference in hospitalizations between those with and without vascular disease [rate ratio (RR) 1.04, 95% CI 0.86–1.24 for all‐cause, and RR 0.84 95% CI 0.69–1.02 for HF hospitalization]. HF with preserved EF was more common in participants without vascular disease (67.0% vs. 55.0%, P = 0.040).

Conclusion

A significant proportion of HF in older adults develops without prior vascular disease. Outcomes for these patients are poor compared with those with preceding vascular disease. These data suggest the need for more targeted HF prediction and prevention efforts.
1,3,2‐Diselena‐ and 1,3,2‐Ditelluraphospholanes with an Annelated 1,2‐Dicarba‐closo‐dodecaborane(12) Unit
Authors: Wrackmeyer Bernd , Klimkina Elena V. , Milius Wolfgang
Published: February 2014

The exchange reactions of phosphorus dihalides RPX2[R =iPr, cyclohexyl (Cy),tBu, (3,5‐Me2‐C6H3)CH2, Ph; X = Cl, Br], EtOPCl2, Et2NPCl2, Cl2PCH2PCl2, and Cl2PCH2CH2PCl2with 2,2‐dimethyl‐4,5‐[1,2‐dicarba‐closo‐dodecaborano(12)]‐1,3‐diselena‐2‐silacyclopentane provide a straightforward route to 1,3,2‐diselenaphospholanes. Some tellurium analogues were prepared from the dilithium salt [1,2‐(LiTe)2‐1,2‐C2B10H10] and were more difficult to characterize. For the selenium compounds, some of the P‐organosubstituted five‐membered rings dimerize to give ten‐membered rings, most readily with the more bulky alkyl groups such astBu. This was not observed for the tellurium compounds. The conformations of the five‐membered rings were studied by NMR spectroscopy and DFT methods. Striking structural differences were clear for the 2‐phenyl‐1,3,2‐diselenaphospholane derivative in solution and in the solid state. All reactions were monitored by multinuclear magnetic resonance spectroscopy (1H,11B,13C,31P,77Se, and125Te NMR), and solution‐state structures could be proposed. Remarkably large secondary isotope effects as isotope‐induced chemical shifts2Δ12/13C(31P) exerted by the carborane carbon atoms were observed; this is apparently a special property of the five‐membered ring. The gas‐phase structures were optimized by DFT methods [B3LYP/6‐311+G(d,p) level of theory], and the NMR parameters were calculated. Two 1,3,2‐diselenaphospholanes and one dimer were characterized by X‐ray analysis.
Guanidinium‐Based Artificial Receptors for Binding Orthophosphate in Aqueous Solution
Authors: Kataev Evgeny A. , Müller Christoph , Kolesnikov Grigory V. , Khrustalev Victor N.
Published: February 2014

Receptors based on guanidinium‐ and pyrrole‐containing binding sites were designed and synthesized for selective recognition of orthophosphate in aqueous solution. Various analytical techniques were used to understand solution behavior and anion binding properties of the receptors in methanol and methanol/water mixtures. Binding studies revealed that the structure of pyrrole‐containing binding sites has great influence on selectivity of receptors for orthophosphate. The receptor with bulky substituents in the meso‐position of the dipyrrolylmethane core demonstrated the highest selectivity for orthophosphate over other inorganic anions.
N‐glycomic profiling of a glucosidase II mutant of Dictyostelium discoideum by ‘‘off‐line’’ liquid chromatography and mass spectrometry
Authors: Hykollari Alba , Dragosits Martin , Rendić Dubravko , Wilson Iain B. H. , Paschinger Katharina
Published: February 2014

In this study, we have performed the first mass spectrometric analysis of N‐glycans of the M31 mutant strain of the cellular slime mould Dictyostelium discoideum, previously shown to have a defect in glucosidase II. Together with glucosidase I, this enzyme mediates part of the initial processing of N‐glycans; defects in either glucosidase are associated with human diseases and result in an accumulation of incorrectly processed oligosaccharides which are not, or only poor, substrates for a range of downstream enzymes. To examine the effect of the glucosidase II mutation in Dictyostelium, we employed off‐line LC‐MALDI‐TOF MS in combination with chemical and enzymatic treatments and MS/MS to analyze the neutral and anionic N‐glycans of the mutant as compared to the wild type. The major neutral species were, as expected, of the composition Hex10–11HexNAc2–3 with one or two terminal glucose residues. Consistent with the block in processing of neutral N‐glycans caused by the absence of glucosidase II, fucose was apparently absent from the N‐glycans and bisecting N‐acetylglucosamine was rare. The major anionic oligosaccharides were sulfated and/or methylphosphorylated forms of Hex8–11HexNAc2–3, many of which surprisingly lacked glucose residues entirely. As anionic N‐glycans are considered to be mostly associated with lysosomal enzymes in Dictyostelium, we hypothesise that glycosidases present in the acidic compartments may act on the oligosaccharides attached to such slime mould proteins. Furthermore, our chosen analytical approach enabled us, via observation of diagnostic negative‐mode MS/MS fragments, to determine the fine structure of the methylphosphorylated and sulfated N‐glycans of the M31 glucosidase mutant in their native state.
Altered structural brain connectome in young adult fragile X premutation carriers
Authors: Leow Alex , Harvey Danielle , Goodrich‐Hunsaker Naomi J. , Gadelkarim Johnson , Kumar Anand , Zhan Liang , Rivera Susan M. , Simon Tony J.
Published: February 2014

Fragile X premutation carriers (fXPC) are characterized by 55–200 CGG trinucleotide repeats in the 5′ untranslated region on the Xq27.3 site of the X chromosome. Clinically, they are associated with the fragile X‐Associated Tremor/Ataxia Syndrome, a late‐onset neurodegenerative disorder with diffuse white matter neuropathology. Here, we conducted first‐ever graph theoretical network analyses in fXPCs using 30‐direction diffusion‐weighted magnetic resonance images acquired from 42 healthy controls aged 18–44 years (HC; 22 male and 20 female) and 46 fXPCs (16 male and 30 female). Globally, we found no differences between the fXPCs and HCs within each gender for all global graph theoretical measures. In male fXPCs, global efficiency was significantly negatively associated with the number of CGG repeats. For nodal measures, significant group differences were found between male fXPCs and male HCs in the right fusiform and the right ventral diencephalon (for nodal efficiency), and in the left hippocampus [for nodal clustering coefficient (CC)]. In female fXPCs, CC in the left superior parietal cortex correlated with counting performance in an enumeration task. Hum Brain Mapp 35:4518–4530, 2014. © 2014 Wiley Periodicals, Inc.
Peer Exclusion is Linked to Inhibition with Familiar but not Unfamiliar Peers at Two Years of Age
Authors: Gazelle Heidi , Faldowski Richard A.
Published: February 2014

This study examined the extent that inhibition among familiar peers was related to inhibition among unfamiliar peers versus exclusion by familiar peers at 2 years of age. Peer inhibition at 2 years of age was assessed by both mothers and teachers on versions of the Behavioral Inhibition Questionnaire and the Preschool Play Behavior Scale (N = 141 children, 53% girls) that were adapted such that each item was posed separately regarding familiar versus unfamiliar peers. A subset of participants (n = 82) were also observed during free‐play with familiar childcare classmates at 30 months using the Peer Interaction Observation System – Early Childhood. There was no significant relation between children exhibiting extreme levels of inhibition with familiar versus unfamiliar peers across informants. Substantial numbers of children demonstrated inhibition with familiar but not unfamiliar peers (18%), with unfamiliar but not familiar peers (10%), or with neither familiar nor familiar peers (69%). In contrast, few children exhibited inhibition with both familiar and unfamiliar peers (3%). Observed peer exclusion among familiar childcare peers was systematically positively correlated with the display of inhibition among familiar childcare peers but not unfamiliar peers across informants. These findings suggest that proximal relational learning processes may have more impact than inhibited temperament on inhibition among familiar peers at 2 years of age. However, the concurrent correlational nature of this study does not provide evidence about the direction of effect. Additionally, in the future, it will be important to conduct observations of children's interactions with both familiar and unfamiliar peers. Copyright © 2014 John Wiley & Sons, Ltd.
Brain Electrical Activity of Shy and Non‐Shy Preschool‐Aged Children During Executive Function Tasks
Authors: Wolfe Christy D. , Bell Martha Ann
Published: February 2014

Psychophysiological and cognitive performance differences exist between shy and non‐shy individuals. Neuroimaging studies have shown identifiable differences in task‐related cortical functioning between adults with and without sensitivity to social events. The current study compared baseline and task measures of EEG power (6–9 Hz) for 125 shy and non‐shy children between the ages of 41 and 55 months who differed in core executive function (EF) skills. Results indicated an increase in medial frontal EEG power from baseline‐to‐task for high EF performers (shy and non‐shy). Shy/low EF performers also demonstrated this increase, but the non‐shy/low EF group did not. For the medial parietal region, only the shy children (high and low EF performers) showed an increase in power from baseline‐to‐task; and for the shy/high EF group, left hemisphere power was greater than the right during baseline and task. This study is believed to be the first continuous‐recording EEG comparison between children who are shy and non‐shy in the context of an EF assessment. These findings highlight differences in medial frontal and medial parietal power for children who differ in shyness and EF skills. They also suggest the value of future research examining strong EF skills as protective and regulatory for shy children. Copyright © 2014 John Wiley & Sons, Ltd.
Catalysis and inactivation of tyrosinase in its action on hydroxyhydroquinone
Authors: del Mar Garcia‐Molina Maria , Muñoz‐Muñoz Jose Luis , Berna Jose , García‐Ruiz Pedro Antonio , Rodriguez‐Lopez Jose Neptuno , Garcia‐Canovas Francisco
Published: February 2014

Hydroxyhydroquinone (HHQ) was characterized kinetically as a tyrosinase substrate. A kinetic mechanism is proposed, in which HHQ is considered as a monophenol or as an o‐diphenol, depending on the part of the molecule that interacts with the enzyme. The kinetic parameters obtained from an analysis of the measurements of the initial steady state rate of 2‐hydroxy p‐benzoquinone formation were
= 229.0 ± 7.7 s−1 and
= 0.40 ± 0.05 mM. Furthermore, the action of tyrosinase on HHQ led to the enzyme's inactivation through a suicide inactivation mechanism. This suicide inactivation process was characterized kinetically by
(the apparent maximum inactivation constant) and r, the number of turnovers made by 1 mol of enzyme before being inactivated. The values of
and r were (8.2 ± 0.1) × 10−3 s−1 and 35,740 ± 2,548, respectively. © 2014 IUBMB Life, 66(2):122–127, 2014
Osteogenic differentiation on DLC‐PDMS‐h surface
Authors: Soininen Antti , Kaivosoja Emilia , Sillat Tarvo , Virtanen Sannakaisa , Konttinen Yrjö T. , Tiainen Veli‐Matti
Published: February 2014

The hypothesis was that anti‐fouling diamond‐like carbon polydimethylsiloxane hybrid (DLC‐PDMS‐h) surface impairs early and late cellular adhesion and matrix–cell interactions. The effect of hybrid surface on cellular adhesion and cytoskeletal organization, important for osteogenesis of human mesenchymal stromal cells (hMSC), where therefore compared with plain DLC and titanium (Ti). hMSCs were induced to osteogenesis and followed over time using scanning electron microscopy (SEM), time‐of‐flight secondary ion mass spectrometry (ToF‐SIMS), immunofluorescence staining, quantitative real‐time polymerase chain reaction (qRT‐PCR), and hydroxyapatite (HA) staining. SEM at 7.5 hours showed that initial adherence and spreading of hMSC was poor on DLC‐PDMS‐h. At 5 days some hMSC were undergoing condensation and apoptotic fragmentation, whereas cells on DLC and Ti grew well. DAPI–actin–vinculin triple staining disclosed dwarfed cells with poorly organized actin cytoskeleton‐focal complex/adhesion‐growth substrate attachments on hybrid coating, whereas spread cells, organized microfilament bundles, and focal adhesions were seen on DLC and in particular on Ti. Accordingly, at day one ToF‐SIMS mass peaks showed poor protein adhesion to DLC‐PDMS‐h compared with DLC and Ti. COL1A1, ALP, OP mRNA levels at days 0, 7, 14, 21, and/or 28 and lack of HA deposition at day 28 demonstrated delayed or failed osteogenesis on DLC‐PDMS‐h. Anti‐fouling DLC‐PDMS‐h is a poor cell adhesion substrate during the early protein adsorption‐dependent phase and extracellular matrix‐dependent late phase. Accordingly, some hMSCs underwent anoikis‐type apoptosis and failed to complete osteogenesis, due to few focal adhesions and poor cell‐to‐ECM contacts. DLC‐PDMS‐h seems to be a suitable coating for non‐integrating implants/devices designed for temporary use. © 2014 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 102B: 1462–1472, 2014.
2‐Distance Coloring of Sparse Graphs
Authors: Bonamy Marthe , Lévêque Benjamin , Pinlou Alexandre
Published: February 2014

For graphs of bounded maximum average degree, we consider the problem of 2‐distance coloring, that is, the problem of coloring the vertices while ensuring that two vertices that are adjacent or have a common neighbor receive different colors. We prove that graphs with maximum average degree less than and maximum degree Δ at least 4 are 2‐distance ‐colorable, which is optimal and improves previous results from Dolama and Sopena, and from Borodin et al. We also prove that graphs with maximum average degree less than (resp. , ) and maximum degree Δ at least 5 (resp. 6, 8) are list 2‐distance ‐colorable, which improves previous results from Borodin et al., and from Ivanova. We prove that any graph with maximum average degree m less than and with large enough maximum degree Δ (depending only on m) can be list 2‐distance ‐colored. There exist graphs with arbitrarily large maximum degree and maximum average degree less than 3 that cannot be 2‐distance ‐colored: the question of what happens between and 3 remains open. We prove also that any graph with maximum average degree can be list 2‐distance ‐colored (C depending only on m). It is optimal as there exist graphs with arbitrarily large maximum degree and maximum average degree less than 4 that cannot be 2‐distance colored with less than colors. Most of the above results can be transposed to injective list coloring with one color less.
Projected changes in hailstorms during the 21st century over the UK
Authors: Sanderson M. G. , Hand W. H. , Groenemeijer P. , Boorman P. M. , Webb J. D. C. , McColl L. J.
Published: February 2014

Hailstorms can pose a significant threat to society, by damaging property and disrupting livelihoods. An understanding of how hailstorm characteristics may change under a warming climate is therefore important for assessing the risk of hail damage for the insurance industry. A simple model of hailstone formation has been driven using meteorological data produced by a regional climate model (RCM) to project how hailstorm numbers and hailstone sizes could change during the 21st century in the UK. Evaluation of the modelled hailstone sizes, numbers and spatial distributions showed that they agreed reasonably well with observations. The effect of climate change on the numbers of damaging hailstorms in the UK (hailstones with diameters greater than 15 mm) was then investigated. A downward trend in the total number of damaging hailstorms during the 21st century was projected, with statistically significant trends for hailstones with diameters between 21 and 50 mm. Melting of hailstones made little contribution to the projected reductions. The results are subject to large uncertainties, some of which originate with the convective parameterization scheme used by the climate model.
The role of traditional varieties of tomato as sources of functional compounds
Authors: Cortés‐Olmos Carles , Leiva‐Brondo Miguel , Roselló José , Raigón María D , Cebolla‐Cornejo Jaime
Published: February 2014

BACKGROUND

Traditional varieties of tomato, usually associated with excellent organoleptic quality, are increasingly appreciated in European quality markets. A collection of 126 populations of 16 traditional varieties from the east of Spain (a secondary diversity center for tomato) have been evaluated over 2 years in order to determine their potential value as sources of functional compounds, including ascorbic acid, lycopene, β‐carotene and total phenolic content.

RESULTS

Population and population × year interaction significantly affected lycopene and ascorbic acid contents, while year effect was also significant for β‐carotene. Despite finding some global trends in certain varieties concerning their functional value, high levels of variation have been found at the intra‐varietal level. Populations with high levels of the compounds analysed have been found, as well as different levels of intra‐population and inter‐year variation. Maximum mean contents for both years have reached 308 mg kg−1 ascorbic acid, 130 mg kg−1 lycopene, 30 mg kg−1 β‐carotene and 89 mg caffeic acid 100 g−1 total phenolic contents, though it is difficult to identify accessions with joint high values of the three compounds.

CONCLUSION

These results open the possibility to promote traditional materials as sources of functional compounds, thus strengthening their quality niches and consolidating their price premium. Additionally, these materials could also be used in breeding programs for quality. © 2014 Society of Chemical Industry
Esterification of fatty acids by Penicillium crustosum lipase in a membrane reactor
Authors: Possebom Gessica , Nyari Nádia LD , Zeni Jamile , Steffens Juliana , Rigo Elisandra , Di Luccio Marco
Published: February 2014

BACKGROUND

This study investigated the performance of a membrane reactor system for esterification of oleic acid and butyric acid with ethanol by Penicillium crustosum lipase using polyethersulfone membranes with molecular weight cut‐offs of 30, 60 and 100 kDa at pressures up to 200 kPa.

RESULTS

The confinement of lipase with 60 and 100 kDa membranes showed the best results. The esterification of butyric acid in the membrane reactor and with free lipase showed higher conversions than those obtained with oleic acid, since the system operated with oleic acid was more subject to fouling and thus could not be run for repeated cycles.

CONCLUSION

The confinement of lipase from P. crustosum in a membrane reactor was possible, resulting in the satisfactory conversion of butyric acid to ethyl butyrate with the possibility of reuse of the immobilized enzyme. © 2014 Society of Chemical Industry
Concept of double salt fortification; a tool to curtail micronutrient deficiencies and improve human health status
Authors: Sultan Saira , Anjum Faqir Muhammad , Butt Masood Sadiq , Huma Nuzhat , Suleria Hafiz Ansar Rasul
Published: February 2014

Fortification of food with micronutrients such as vitamins and minerals is one of the main strategies used to combat micronutrient deficiencies. Fortification in common salt is a fruitful strategy because of the daily consumption of 5–12 g salt per person globally. Therefore double fortification of salt with iodine and iron could be a reasonable approach to prevent both iodine and iron deficiencies. It is reckoned that about two billion people are iodine‐deficient worldwide. Iodine deficiency during pregnancy may affect the health status of both mother and fetus and increase infant mortality. Deficiencies of both these micronutrients during childhood affect somatic growth and cognitive and neurological function. Thyroid metabolism is negatively affected by iron deficiency and reduced effectiveness of iodine prophylaxis in areas of endemic goiter. High prevalence of iron deficiency among children may be reduced by the application of effective iodized salt programs. However, ensuring the stability and bioavailability of both iron and iodine as double‐fortified salt is difficult. Iodine present in iodide or iodate form in dual‐fortified salt is oxidized to free iodine in the presence of ferrous ions and oxygen and consequently loses its characteristics. Moreover, ferrous iron is more bioavailable but is readily oxidized to the less bioavailable ferric form. However, both forms of iron may lead to discoloration of the final product, which can be reduced by providing a physical barrier around the iron. Salt encapsulation is one of the best tools to provide a physical barrier for undesirable reactions and interactions during storage. In this review the concept of dual salt fortification, the impact of fortification on curing various life‐threatening maladies, latest assessments of mineral deficiencies and the choice of fortificants are discussed. © 2014 Society of Chemical Industry
Facile Production of Polypyrrole Nanofibers Using a Freeze‐Drying Method
Authors: Lee Doyun , Zhang Chengyi , Gao Haifeng
Published: February 2014

Conjugated polymer nanofibers with lengths of tens of micrometers and diameters of hundreds of nanometers are prepared via the assembly of polypyrrole (PPy) nanoparticles in water using a freeze‐drying method. The structure and uniformity of the PPy nanofibers are critically affected by the processing conditions, such as the freezing temperature and the concentration of the latex dispersion. These nanofibers are subsequently applied as vapor sensors for efficient detection of organic explosive chemicals.

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Alpha‐synuclein repeat variants and survival in Parkinson's disease
Authors: Chung Sun Ju , Biernacka Joanna M. , Armasu Sebastian M. , Anderson Kari , Frigerio Roberta , Aasly Jan O. , Annesi Grazia , Bentivoglio Anna Rita , Brighina Laura , Chartier‐Harlin Marie‐Christine , Goldwurm Stefano , Hadjigeorgiou Georgios , Jasinska‐Myga Barbara , Jeon Beom Seok , Kim Yun Joong , Krüger Rejko , Lesage Suzanne , Markopoulou Katerina , Mellick George , Morrison Karen E. , Puschmann Andreas , Tan Eng‐King , Crosiers David , Theuns Jessie , Van Broeckhoven Christine , Wirdefeldt Karin , Wszolek Zbigniew K. , Elbaz Alexis , Maraganore Demetrius M. ,   on behalf of the Genetic Epidemiology of Parkinson's Disease Consortium
Published: February 2014

Objectives

To determine whether α‐synuclein dinucleotide repeat (REP1) genotypes are associated with survival in Parkinson's disease (PD).

Methods

Investigators from the Genetic Epidemiology of Parkinson's Disease Consortium provided REP1 genotypes and baseline and follow‐up clinical data for cases. The primary outcome was time to death. Cox proportional hazards regression models were used to assess the association of REP1 genotypes with survival.

Results

Twenty‐one sites contributed data for 6,154 cases. There was no significant association between α‐synuclein REP1 genotypes and survival in PD. However, there was a significant association between REP1 genotypes and age at onset of PD (hazard ratio: 1.06; 95% confidence interval: 1.01‐1.10; P value = 0.01).

Conclusions

In our large consortium study, α‐synuclein REP1 genotypes were not associated with survival in PD. Further studies of α‐synuclein's role in disease progression and long‐term outcomes are needed. © 2014 International Parkinson and Movement Disorder Society
Scars of Parturition? Influences Beyond Parity
Authors: Maass P. , Friedling L. J.
Published: February 2014

In the 40 years since the phrase ‘scars of parturition’ was coined, studies have attempted to show the relationship between scars on the bony pelvis and parity history. Despite numerous studies, the relationship of parity and scarring remains unclear. The challenge facing these studies is the rarity of skeletal collections of known parity. The alternative study approach is examining relationships between scars and factors other than pregnancy‐related strains that may affect their manifestation.

Skeletal remains of 312 individuals were examined for scarring at the dorsal pubic surface, pubic tubercle, preauricular sulcus, interosseous groove and iliac tuberosity. Pelvic and femoral measurements were also taken. Features were compared according to sex and age. Principal components analysis was performed to assess the influence of body and pelvic size on scar manifestation.

Scars occurred in both sexes, although they were more common and more severe in females. Scar severity remained unchanged or increased with age in both sexes. Females had smaller bodies but larger pelves than males. The interspinous and transverse inlet diameters and the femur measurements increased with age. Principal components analysis showed that body and pelvic sizes represented the majority of the observed variation, with scars occurring more commonly in small‐bodied individuals with large pelves, most of which were females. Both sexes also show a difference in the magnitude of scarring at the pubis and ilium.

These results suggest that weight‐bearing and pelvic stability may be a better explanation for scarring than parturition‐related strain. Female pelves are more flexible and require more ligamentous stabilization, causing increased scar formation. The weight‐bearing strain on male pelves may sometimes also be sufficiently large to cause similar scars.

Future studies may be able to test this theory on samples of known parity history. Copyright © 2014 John Wiley & Sons, Ltd.