bluuebunny/crossref_metadata_2025_split huggingface dataset:
Maternal overweight and obesity and the risk of neural tube defects: A case–control study in China
Authors: Gao Li‐Jie , Wang Zhi‐Ping , Lu Qing‐Bin , Gong Rui , Sun Xi‐Hong , Zhao Zhong‐Tang 
Published: March 2013

AbstractBACKGROUNDStudies have suggested that being obese before pregnancy is a risk factor for neural tube defects (NTDs), while results of many studies are controversial. This study aims to explore the association between maternal overweight and obesity before pregnancy and risk of NTDs.METHODSA 1:1 matched case–control study was conducted. Cases were 459 women who delivered infants or conceived fetuses with NTDs in two provinces of China and controls were 459 women with live‐born infants, without an apparent congenital malformation, matched with cases by region, delivery hospital, and year of childbirth.RESULTSCompared with normal body weight, maternal obesity (body mass index, BMI ≥ 28 kg/m2) before pregnancy had a significant increased risk for NTDs as a group after adjusting for age, occupation, educational level, family income, parity, and use of folic acid (odds ratio, OR = 2.45; p < 0.05). No significant increase in NTD risk was found for maternal underweight (BMI < 18.5 kg/m2) and overweight (BMI from 24 to 28 kg/m2). For three subtypes of NTDs, anencephaly, spina bifida, and encephalocele, no significant increase in risk was found with maternal underweight, overweight, or obesity (all, p > 0.05).CONCLUSIONMaternal obesity before pregnancy is associated with risk of NTDs and should be considered in maternal reproductive health care. Birth Defects Research (Part A), 2013. © 2013 Wiley Periodicals, Inc.
Neurotoxicity Assessment of Artemether in Juvenile Rats
Authors: Beckman David A. , Youreneff Maureen , Butt Mark T. 
Published: March 2013

BACKGROUNDOral administration of artemether in combination with lumefantrine is approved for the treatment of malaria in adults and children. In adult animals, artemether can produce neurotoxicity with intramuscular, but not oral, administration. Herein, the potential of orally administered artemether to produce neurotoxicity in juvenile rats was investigated.METHODSIn the first study, the toxicity of artemether was evaluated in juvenile rats dosed with 0, 10, 30, and 100mg/kg/day on postpartum days (ppds) 7 to 21. In‐life, clinical pathology, anatomic pathology, behavioral, and toxicokinetics evaluations were performed. The second study focused on neurotoxicity during different dosing intervals, with doses of 0, 30, and 80mg/kg/day on ppds 7 to 13, and doses of 0, 30, and 120mg/kg/day on ppds 14 to 21, 22 to 28, and 29 to 36. For each dosing interval, in‐life, extensive histology, toxicokinetics, and behavioral evaluations were performed. In the third study, toxicokinetics evaluations in the adult were conducted at 20 and 200mg/kg/day.RESULTSThe first study demonstrated increased mortality, renal necrosis, and brain hemorrhage at ≥30mg/kg/day with no persistent effects in surviving animals. In the second study, increased mortality, body weight effects, and a trend toward increased exposure were observed in the ppd 14 and younger animals. Neither specific neurotoxicity nor persistent effects were seen. The toxicokinetic study in adults revealed lower exposures as compared to those in the younger juvenile rats.CONCLUSIONSAs in the adult rat, oral administration of artemether in the juvenile rat is not associated with the neurotoxicity produced by intramuscular administration.
Pharmacokinetics, protein binding and metabolism of a quinoxaline urea analog as an NF‐κB inhibitor in mice and rats by LC‐MS/MS
Authors: Gautam Nagsen , Bathena Sai Praneeth R. , Chen Qianyi , Natarajan Amarnath , Alnouti Yazen 
Published: March 2013

ABSTRACT13–197 is a novel NF‐κB inhibitor that shows promising in vitro efficacy data against pancreatic cancer. In this study, we characterized the pharmacokinetics, tissue distribution, protein binding and metabolism of 13–197 in mice and rats. A valid, sensitive and selective LC‐MS/MS method was developed. This method was validated for the quantification of 13–197, in the range of 0.1 or 0.2‐500 ng/mL in mouse plasma, liver, kidney, lung, heart, spleen, brain, urine and feces. 13–197 has low bioavailability of 3 and 16% in mice and rats, respectively. It has faster absorption in mice with 12‐fold shorter Tmax than in rats. Tissue concentrations were 1.3–69.2‐fold higher in mice than in rats at 72 h after intravenous administration. 13–197 is well distributed to the peripheral tissues and has relatively high tissue–plasma concentration ratios, ranging from 1.8 to 3634, in both mice and rats. It also demonstrated more than 99% binding to plasma proteins in both mice and rats. Finally, <1% of 13–197 is excreted unchanged in urine and feces, and metabolite profiling studies detected more than 20 metabolites in mouse and rat plasma, urine and feces, which indicates that 13–197 is extensively metabolized and primarily eliminated by metabolism rather than by excretion. Copyright © 2013 John Wiley & Sons, Ltd.
Comparative pharmacokinetic studies of andrographolide and its metabolite of 14‐deoxy‐12‐hydroxy‐andrographolide in rat by ultra‐performance liquid chromatography–mass spectrometry
Authors: Yang Tao , Xu Chong , Wang Zheng Tao , Wang Chang Hong 
Published: March 2013

ABSTRACTAndrographolide (AND), one of the major diterpenoids from Andrographis paniculata (Burm. f.) Nees, can be metabolized as a phase two metabolite of 14‐deoxy‐12‐hydroxy‐andrographolide‐19‐O‐β‐d‐glucuronide in human. The aim of this study is to characterize and synthesize the phase one metabolite of 14‐deoxy‐12‐hydroxy‐andrographolide (DEO‐AND) after gavage feeding of AND in rats, and to compare the pharmacokinetics of AND and DEO‐AND after intravenous administration. DEO‐AND was first discovered existing in rat serum by HPLC‐MSn after administration of AND. Furthermore, the target metabolite was synthesized and elucidated by NMR. In addition, a rapid, selective and sensitive UPLC‐ESI/MS method was developed for the first time to determine the content of AND and DEO‐AND in rats serum. The method was successfully applied to a pharmacokinetic study in rats after a single intravenous dose of 5 mg/kg AND and DEO‐AND, respectively. In comparison, the pharmacokinetic parameters of metabolite DEO‐AND, including distribution rate constant, elimination rate constant, half‐life and mean residence time, were significantly less than those of AND (p < 0.05). However, the AUC0→720 min value after intravenous administration of DEO‐AND was 781.59 ± 81.46 µg min/mL, which was 17.71 times higher than that of AND (44.13 ± 10.45 µg min/mL; p < 0.05). These results show the pharmacokinetic profile of AND to be significantly different from that of DEO‐AND by intravenous administration. Copyright © 2013 John Wiley & Sons, Ltd.
Bioactivity‐integrated ultra‐performance liquid chromatography/quadrupole time‐of‐flight mass spectrometry for the identification of nuclear factor‐κB inhibitors and β2 adrenergic receptor agonists in Chinese medicinal preparation Chuanbeipipa dropping pills
Authors: Dong Linyi , Luo Yi , Cheng Binfeng , Zhang Yaoshu , Zhang Ning , Hou Yuanyuan , Jiang Min , Luo Guoan , Bai Gang 
Published: March 2013

ABSTRACTA simple and dual‐target method based on ultra‐performance liquid chromatography/quadrupole time‐of‐flight mass spectrometry combined with dual‐bioactive [nuclear factor‐κB (NF‐κB) and β2‐adrenergic receptor] luciferase reporter assay systems was developed to rapidly characterize the chemical structure of various bioactive compounds of TCM preparations. Chuanbeipipa dropping pills, a traditional Chinese medicine preparation used for the clinical therapy of chronic obstructive lung disease and cough caused by bronchial catarrh, was analyzed with this method. Potential anti‐inflammatory and spasmolytic constituents were screened using NF‐κB and β2‐adrenergic receptor activity luciferase reporter assay systems and simultaneously identified according to the time‐of‐flight mass spectrometry data. One β2‐adrenergic receptor agonist (ephedrine) and two structural types of NF‐κB inhibitors (platycosides derivatives and ursolic acid derivatives) were characterized. Platycodin D3 and E were considered new NF‐κB inhibitors. Further cytokine and chemokine detection confirmed the anti‐inflammatory effects of the potential NF‐κB inhibitors. Compared with conventional fingerprints, activity‐integrated fingerprints that contain both chemical and bioactive details offer a more comprehensive understanding of the chemical makeup of plant materials. This strategy clearly demonstrated that multiple bioactivity‐integrated fingerprinting is a powerful tool for the improved screening and identification of potential multi‐target lead compounds in complex herbal medicines. Copyright © 2013 John Wiley & Sons, Ltd.
Fischer–Tropsch Synthesis Over Cobalt Supported On Silica‐Incorporated Mesoporous Carbon
Authors: Karandikar Prashant R. , Park Jo‐Yong , Lee Yun‐Jo , Jun Ki‐Won , Ha Kyoung‐Su , Kwak Geun Jae , Park Hae‐Gu , Cheon Joo Yeong 
Published: March 2013

AbstractThe influence of carbon–silica hybrid supports on cobalt catalysts in Fischer–Tropsch synthesishas been investigated. Mesoporous carbon–silica hybrid supports were synthesized through a hydrogen‐bonding‐assisted self‐assembly route by loading different amounts of silica (0 to 45 %) as a framework composition with mesoporous carbon. These carbon and hybrid supports were then impregnated with 15 wt. % cobalt and the resulting catalysts were characterized by various physicochemical, gravimetric, and spectroscopic methods. The dispersion of silica in the framework of mesoporous carbon modified the surface chemistry and enhanced the wetting properties of the support. Hence, the dispersion and reducibility of cobalt over the hybrid supports increased compared to those of the carbon‐supported catalyst. However, above the optimum silica incorporation of 34 %, the possibility of phase separation and structural transformation of silica at the high carbonization temperature decreased the dispersion and reducibility of the supported Co catalysts. The carbon‐supported catalyst showed a quick drop in the activity during the initial stages of the reaction due to the migration of cobalt particles over the hydrophobic and inert support surface. On the contrary, carbon–silica hybrid supports inhibited the mobility of cobalt particles and produced a higher density of active Co0 sites, leading to a higher initial activity. Carbon–silica‐supported catalysts with a silica content of up to 34 % were found to exhibit excellent steady state Fischer–Tropsch synthesis activity and C5+ selectivity compared to only carbon and carbon–silica‐supported catalyst with >34 % silica incorporation.
A Remarkable cis‐ and trans‐Spanning Dibenzylidene Acetone Diphosphine Chelating Ligand (dbaphos)
Authors: Jarvis Amanda G. , Sehnal Petr E. , Bajwa Somia E. , Whitwood Adrian C. , Zhang Xiangbiao , Cheung Man Sing , Lin Zhenyang , Fairlamb Ian J. S. 
Published: March 2013

AbstractA multidentate and flexible diolefin–diphosphine ligand, based on the dibenzylidene acetone core, namely dbaphos (1), is reported herein. The ligand adopts an array of different geometries at Pt, Pd and Rh. At PtII the dbaphos ligand forms cis‐ and trans‐diphosphine complexes and can be defined as a wide‐angle spanning ligand. 1H NMR spectroscopic analysis shows that the β‐hydrogen of one olefin moiety interacts with the PtII centre (an anagostic interaction), which is supported by DFT calculations. At Pd0 and RhI, the dbaphos ligand exhibits both olefin and phosphine interactions with the metal centres. The Pd0 complex of dbaphos is dinuclear, with bridging diphosphines. The complex exhibits the coordination of one olefin moiety, which is in dynamic exchange (intramolecular) with the other “free” olefin. The Pd0 complex of dbaphos reacts with iodobenzene to afford trans‐[PdII(dbaphos)I(Ph)]. In the case of RhI, dbaphos coordinates to form a structure in which the phosphine and olefin moieties occupy both axial and equatorial sites, which stands in contrast to a related bidentate olefin, phosphine ligand (“Lei” ligand), in which the olefins occupy the equatorial sites and phosphines the axial sites, exclusively.
Versatile Supramolecular Cross‐Linker: A Rotaxane Cross‐Linker That Directly Endows Vinyl Polymers with Movable Cross‐Links
Authors: Arai Takayuki , Jang Keumhee , Koyama Yasuhito , Asai Shigeo , Takata Toshikazu 
Published: March 2013

AbstractA supramolecular cross‐linked cross‐linker, capable of introducing rotaxane cross‐links to vinyl polymers, has been developed for the rational synthesis of polyrotaxane networks. The experimental results reveal that the combination of an oligocyclodextrin (OCD) and a terminal bulky group‐tethering macromonomer (TBM) forms a polymer‐network structure having polymerizable moieties through supramolecular cross‐linking. Radical polymerization of a variety of typical vinyl monomers in the presence of the vinylic supramolecular cross‐linker (VSC) afforded the corresponding vinyl polymers cross‐linked through the rotaxane cross‐links (RCP) as transparent stable films in high yields under both photoinitiated and thermal polymerization conditions. A poly(N,N‐dimethylacrylamide)‐based hydrogel synthesized by using VSC, RCPDMAAm, displayed a unique mechanical property. The small‐angle X‐ray scattering (SAXS) results, indicating patterns characteristic of a polyrotaxane network, clearly suggested the presence and role of the rotaxane cross‐links. The confirmation of the introduction of rotaxane‐cross‐links into vinyl polymers strongly reveals the significant usefulness of VSC.
Sedimentary Records of Evolution of Heavy Metals in Songhua Lake, Northeast China
Authors: Hao Libo , Sun Liji , Zhao Yuyan , Lu Jilong 
Published: March 2013

AbstractIn this paper, the vertical variations of heavy metal elements (including Cd, Cr, Cu, Hg, Mn, Ni, Pb, and Zn) in the sediments of Songhua Lake are analyzed using sediment cores. A 70‐year evolutionary history of these heavy metal elements in Songhua Lake is described and the sources of the heavy metals in the sediments are investigated by evaluating the pollution characteristics of the metals in terms of their enrichment coefficients and geoaccumulation indexes. The results indicate that Cr, Cu, Mn, Ni, Pb, and Zn in the sediments originated mainly from basin erosion and were transported to the lake by rivers. Cd and Hg in the sediments also originated from basin erosion that occurred prior to the mid‐1990s, and these sediments have since been overlaid by artificial pollution. The distribution of heavy metals in the sediments of Songhua Lake is influenced by many factors, including sediment composition, the relative importance of fluvial input, and artificial pollution.
Simultaneous Determination of 11 Sulfonamides by HPLC–UV and Application for Fast Screening of Their Aerobic Elimination and Biodegradation in a Simple Test
Authors: Mahmoud Waleed M. M. , Khaleel Nareman D. H. , Hadad Ghada M. , Abdel‐Salam Randa A. , Haiß Annette , Kümmerer Klaus 
Published: March 2013

AbstractSulfonamides (SAs) are one of the most frequently used antibiotics. SAs have been found in various environmental compartments. If SAs are not degraded in the environment, they can affect bacteria by their antibiotic properties and contribute to bacterial antibiotic resistance. Therefore, the biodegradability of 11 SAs (sulfanilamide, sulfaguanidine monohydrate, sulfadiazine, sulfathiazole, sulfapyridine, sulfamerazine, sulfamethoxypyridazine, sulfachloropyridazine, sulfamethazine, sulfamethoxazole, and sulfadimethoxine) was studied. For this purpose, the Closed Bottle Test (CBT, OECD 301D) was performed, which includes a toxicity control. In order to monitor the environmental fate of the parent compound and to check for transformation products, a simple, efficient, and reliable HPLC–UV method for the simultaneous determination of these SAs has been developed. Acetonitrile and water (with 0.1% formic acid) were used as mobile phase solvents for gradient elution. The method was validated in terms of precision, detection and quantitation limits, selectivity, and analytical solution stability. In the CBT, none of these SAs was readily biodegradable. The HPLC–UV analysis confirmed that no degradation of any SA took place. In the toxicity control, these SAs showed no toxic effect in the used concentration of environmental bacteria applied in the test.
Aspirin is associated with lower melanoma risk among postmenopausal Caucasian women
Authors: Gamba Christina A. , Swetter Susan M. , Stefanick Marcia L. , Kubo Jessica , Desai Manisha , Spaunhurst Katrina M. , Sinha Animesh A. , Asgari Maryam M. , Sturgeon Susan , Tang Jean Y. 
Published: March 2013

AbstractBACKGROUND:Nonsteroidal anti‐inflammatory drugs (NSAIDs) have been associated with decreased risk of gastric, colorectal, and breast cancer. However, the impact of NSAIDs on the risk of melanoma has been inconsistent. The authors evaluated the association between NSAID use and cutaneous melanoma risk in the Women's Health Initiative (WHI) Observational Study (OS).METHODS:At study entry, use of aspirin (acetylsalicylic acid [ASA]) and nonaspirin NSAIDs was assessed among 59,806 postmenopausal Caucasian women ages 50 to 79 years. Cox proportional hazards models were constructed after adjusting for participant skin type, sun exposure history, and medical indications for NSAID use among other confounders.RESULTS:During a median follow‐up of 12 years, 548 incident melanomas were confirmed by medical review. Women who used ASA had a 21% lower risk of melanoma (hazard ratio, 0.79; 95% confidence interval, 0.63‐0.98) relative to nonusers. Increased duration of ASA use (<1 year, 1‐4 years, and ≥5 years) was associated with an 11% lower risk of melanoma for each categorical increase (Ptrend = .01), and women with ≥5 years of use had a 30% lower melanoma risk (hazard ratio, 0.70; 95% confidence interval, 0.55‐0.94). In contrast, use of non‐ASA NSAIDs and acetaminophen were not associated with melanoma risk.CONCLUSIONS:Postmenopausal women who used ASA had a significantly lower risk of melanoma, and longer duration of ASA use was associated with greater protection. Although this study was limited by the observational design and self‐report of NSAID use, the findings suggest that ASA may have a chemopreventive effect against the development of melanoma and warrant further clinical investigation. Cancer 2013. © 2012 American Cancer Society.
Foldings and grazings of tori in current controlled interleaved boost converters
Authors: Giaouris Damian , Banerjee Soumitro , Stergiopoulos Fotis , Papadopoulou Simira , Voutetakis Spyros , Zahawi Bashar , Pickert Volker , Abusorrah Abdullah , Al Hindawi Mohammed , Al‐Turki Yusuf 
Published: March 2013

SUMMARYInterleaved boost converters (IBCs) are used when energy conversion is required at high current levels. Such converter systems may undergo various nonlinear phenomena which can affect their performance adversely. In this paper, we study an IBC and demonstrate the first instability through a Neimark–Sacker bifurcation, resulting in a torus. An analysis based on the calculation of the monodromy matrix reveals that the torus has a rather strange form as the complex Floquet multipliers that became unstable have a real value close to −1. We show that further variation in a parameter can result in novel nonlinear phenomena where the torus itself folds and grazes a switching manifold, resulting in a ‘wobbling’ of the closed loop that represents the torus in discrete time. Numerical and analytical results validate our work. Copyright © 2013 John Wiley & Sons, Ltd.
Analytical modelling and performance evaluation of realistic time‐controlled M2M scheduling over LTE cellular networks
Authors: Gotsis Antonis G. , Lioumpas Athanasios S. , Alexiou Angeliki 
Published: March 2013

ABSTRACTSupporting emerging machine‐to‐machine (M2M) communications over Long‐term Evolution (LTE)/LTE Advanced cellular networks in an efficient way will be beneficial for both telecommunication communities. The first step to migrate to an M2M‐enabled cellular standard is to provide these new services through the existing architectures and protocols, while maintaining seamless backward compatibility. To this end, we thoroughly examined a key LTE Medium Access Control entity, which is the packet scheduler, and proposed solutions based on the time‐controlled M2M feature, to deal with the diverse M2M traffic characteristics and quality‐of‐service requirements. Starting from the single M2M class case, we extended our study to more realistic scenarios, involving more M2M classes with diverse quality‐of‐service requirements. We defined analytical models for predicting the system performance on the basis of queueing theory concepts and considered the interaction between classes with different priorities. The proposed analytical models are validated through extensive system‐level simulations. On the basis of the insight obtained from our analytical approach, we modified an existing scheduling algorithm to improve the performance of low‐priority M2M device groups, and we demonstrated its superior performance both experimentally and analytically. Copyright © 2013 John Wiley & Sons, Ltd.
The rivers of Africa: witness of climate change and human impact on the environment
Authors: Mahe G. , Lienou G. , Descroix L. , Bamba F. , Paturel J. E. , Laraque A. , Meddi M. , Habaieb H. , Adeaga O. , Dieulin C. , Chahnez Kotti F. , Khomsi K. 
Published: March 2013

AbstractIn this paper, we study the impact of climate change on river regimes in several parts of Africa, and we look at the most probable causes of these changes either climatically or anthropogenically driven. We study time series of updated monthly and annual runoff of rivers of North Africa, West Africa (Sahelian and humid tropical regions) and Central Africa, including the largest river basins: Niger and Volta rivers in West Africa, and Congo and Ogooue rivers in Central Africa. The recent years are studied in the perspective of multi‐decadal variability. In West Africa and in a part of Central Africa, the climate has changed since 1970, and rainfall has not returned to previous annual amounts, except in Equatorial Africa. The consequences of the long‐lasting drought are, depending on the area concerned, the modification of seasonal regimes (Equatorial area), the groundwater table decrease (Tropical humid area) and the land cover degradation (Sahelian area). The increasing number of dams and of agricultural areas also plays a major role on the modification of river regimes. The population increase will continue to impact on the environment: land cover change, deforestation, agriculture and increasing number of dams will be associated with a reduction of water and sediment discharges to the sea, and major impacts on downstream ecosystems and coastal areas. It seems necessary to share with stakeholders a comprehensive approach of the water cycle from the basin to the sea, to prevent long‐lasting damages to ecosystems and infrastructures. Copyright © 2013 John Wiley & Sons, Ltd.
Book Reviews
Authors: HUTCHEON DUNCAN E. 
Published: March 2013

Book reviewed in this article:Cardiac Rehabilitation. Lenore R. Zohman and Jerome S. Tobis.Lewis's Pharmacology, 4th Edition. James Crossland.The Economics of Drug Innovation. Joseph D. Cooper, editor.New Aspects of Storage and Release Mechanisms of Catecholamines. H. J. Schumann and G. Kroneberg, editors.Ocular Anti‐Inflammatory Therapy. Herbert E. Kaufman, editor. Charles C ThomasDigitalis Intoxication. Edward K. Chung.