bluuebunny/crossref_metadata_2025 huggingface dataset:
Pharmacogenomics of cancer chemopreventive isothiocyanate compound sulforaphane in the intestinal polyps of ApcMin/+ mice
Authors: Khor Tin Oo , Hu Rong , Shen Guoxiang , Jeong Woo‐Sik , Hebbar Vidya , Chen Chi , Xu Changjiang , Nair Sujit , Reddy Bandaru , Chada Kiran , Kong Ah‐Ng Tony
Published: September 2006

Sulforaphane (SFN) is an isothiocyanate that is present in widely consumed vegetables. Previous studies have shown that SFN is effective in preventing carcinogenesis induced by carcinogens in rodents. Recently it was found that SFN could also suppress the growth of intestinal polyps in the ApcMin/+ mouse. In the present study, the acute effect of SFN on the gene expression profile in small intestinal polyps of ApcMin/+ mice using Affymetrix microarray was performed. SFN is a strong inducer for phase II drug metabolizing enzymes, which is believed to contribute to its chemopreventive properties. However, the results show that genes involved in apoptosis, cell growth and maintenance rather than the predicted phase II genes were modulated. The proapoptotic genes including MBD4, TNFR‐7 and TNF (ligand)‐11 were up‐regulated while pro‐survival genes including cyclin‐D2, integrin‐β1 and Wnt‐9A were down‐regulated. Interestingly, two genes potentially involved in colorectal carcinogenesis, 15‐LOX and COX‐2 were found to be increased and decreased, respectively. In conclusion, the results show, for the first time, that chemopreventive agents such as SFN regulate different set of genes involving apoptosis, cell growth/maintenance and inflammation in the small intestinal polyps of ApcMin/+ mice, which could contribute to the overall chemopreventive pharmacological effects. Copyright © 2006 John Wiley & Sons, Ltd.
Maternal severe migraine and risk of congenital limb deficiencies
Authors: Bánhidy Ferenc , Ács Nándor , Horváth‐Puhó Erzsébet , Czeizel Andrew E.
Published: September 2006

BACKGROUND:

Migraines occurs frequently during pregnancy; however, there are no published data on their possible teratogenic potential in a controlled epidemiological study. Therefore, we examined the risk of congenital abnormalities in infants born to women who had migraines and other headaches during pregnancy.

METHODS:

Between 1980 and 1996, the Hungarian Case‐Control Surveillance of Congenital Abnormalities evaluated 22,843 cases (newborns or fetuses) with congenital abnormalities, 38,151 control newborn infants without any abnormalities, and 834 malformed controls with Down syndrome.

RESULTS:

Migraines anytime during pregnancy occurred in 565 (2.5%) mothers of the case group compared with 713 (1.9%) mothers in the control group (crude prevalence odds ratio [POR], 1.3; 95% confidence interval [CI], 1.2–1.5) and 24 (2.9%) pregnant women in the malformed control group (crude POR, 0.9; 95% CI, 0.6–1.3) The mothers of 247 cases, 533 controls, and 21 malformed controls had severe migraines during the second and/or third months of pregnancy. There was only 1 congenital abnormality group: limb deficiencies, which had a higher rate of maternal migraines during the second and third months of pregnancy both at the comparison of cases and matched controls (adjusted POR, 2.5; 95% CI, 1.1–5.8) and of cases and malformed controls (adjusted POR, 1.7; 95% CI, 1.3–3.0). There was no association between other headaches and different congenital abnormalities at the comparison of cases and controls.

CONCLUSIONS:

Our data showed that maternal severe migraines during the second and/or third months of pregnancy were associated with an increased risk of congenital limb deficiencies. A similar association was not detected between congenital anomalies and other headaches during pregnancy. Our study was not based on a prior hypothesis; therefore, these data can be considered only as a signal that needs confirmation by independent data sets. Birth Defects Research (Part A), 2006. © 2006 Wiley‐Liss, Inc.
Quality and content of abstracts in papers reporting about drug exposures during pregnancy
Authors: Einarson Thomas R. , Lee Crystal , Smith Ryan , Manley Jennifer , Perstin Julia , Loniewska Margaret , Zahedi Payam , Abu‐Ghazalah Rashid , Einarson Adrienne
Published: September 2006

BACKGROUND:

Most clinicians read only the abstract of papers in scientific journals. Therefore, it is very important that abstracts contain as much information as possible, to summarize the data succinctly. Our objectives were to evaluate the quality of information in abstracts reporting human fetal outcomes following drug exposure during pregnancy.

METHODS:

We developed quality criteria based on previous work, modifying them for use with pregnancy outcomes. Quality scores were calculated as present/absent for all of the equally weighted criteria, then expressed as percentages (present/[present + absent]). We examined a random sample of 100 abstracts obtained through searches of MEDLINE, EMBASE, and the Web of Science databases from 1990 to 2005. Average quality scores were compared across designs (cohort, case‐control, meta‐analysis, and mixed design) Using Kruskal‐Wallis ANOVA and structured/unstructured formats using Student's t test.

RESULTS:

the overall average quality was 59.2% ± 14% (median, 61.5%; range, 15.4–83.3%). Quality was not significantly different across designs (P = .16) or between structured and unstructured abstracts (P = .44). Quality scores increased over time (Rho = 0.23, P = .02). Most frequently absent were baseline risk (94%), drug dose (91%), nonsignificant P values (72%), confounders (69%), significant P values (57%), and risk difference (48%).

CONCLUSIONS:

Abstracts provide insufficient information, particularly baseline risk values, for readers to make evidence‐based decisions regarding drug use during pregnancy. Efforts need to be made to improve the quality of abstracts and include critical information such as baseline risk. Birth Defects Research (Part A), 2006. © 2006 Wiley‐Liss, Inc.
The pattern of down syndrome among children in Qatar: A population‐based study
Authors: Wahab Atqah Abdul , Bener Abdulbari , Sandridge Amy L. , Hoffmann Georg F.
Published: September 2006

BACKGROUND:

The objective of the present study was to determine the prevalence pattern of Down Syndrome (DS) in children <5 years of age in the State of Qatar. This is a retrospective descriptive study. The study was conducted in the Hamad General Hospital, Women's Hospital, and Rumailah Hospital (Hamad Medical Corporation). A total of 146 children were reported as having DS during the 6‐year period from 1 January 2000 to December 31, 2005.

METHODS:

The diagnostic classification of definitive DS was made in accordance with criteria based on the International Classification of Disease 10th Revision (ICD‐10). The data collected from the medical records included sociodemographic characteristics of the children, genetic and family history, pedigree analysis, and clinical genetic examination.

RESULTS:

A total of 146 children were diagnosed with DS during the last 6‐year period and the prevalence rate is 19.5 per 10,000 live births. Of these, 40.4% were Qataris and 59.6% were non‐Qataris. DS was slightly more common in boys (52.7%) than girls (47.3%). Infants <1 year old had the highest frequency of DS (40.4%), followed by children (1–2) years (26%). The most common abnormality was regular trisomy (98%). Also, one‐half of the studied children had congenital heart problems (51.7%). There is a significant relationship between DS and maternal age as reported by other studies in other countries.

CONCLUSION:

The identification of specific types of chromosomal abnormalities in DS children is important as it enables clinicians to accurately counsel the parent regarding the recurrence risk and available options. Birth Defects Research (Part A), 2006. © 2006 Wiley‐Liss, Inc.
Outcome of antegrade continence enema procedures for faecal incontinence in adults
Authors: Lefèvre J H , Parc Y , Giraudo G , Bell S , Parc R , Tiret E
Published: September 2006

Background

Faecal incontinence has major consequences. Colostomy has been the mainstay of therapy when other options fail. Operations such as the Malone procedure have been proposed as an alternative. The aim of this study was to evaluate the outcomes and quality of life of patients having a Malone procedure for the treatment of faecal incontinence.

Methods

Charts of patients who had had a Malone procedure or equivalent between 1998 and 2004 were reviewed. The patients completed a Short Form (SF) 36 quality of life questionnaire.

Results

The study included 25 patients (17 female; median age 47 years). In seven, the appendix was used; an ileoneoappendicostomy was performed in the other 18. Three patients were lost to follow-up; the remaining 22 were followed for a median (range) of 21 (1–61) months. Five patients had a cutaneous stenosis; another had the appendicostomy removed and replaced by a colostomy. Four patients no longer used the stoma for irrigation. All other patients were completely clean except one, who reported occasional night-time seepage. The mean SF-36 showed a good physical recovery (43·9) but persisting psychological distress (36·0).

Conclusion

The Malone procedure or equivalent achieves good results in the management of faecal incontinence, although psychological distress persists after surgery.
Surgery for hepatocellular carcinoma in patients with chronic liver disease
Authors: Cherqui D
Published: September 2006

Several options exist
Interpretive flexibility: why doesn't insight incite controversy in mental health law?
Authors: Diesfeld Kate , Sjöström Stefan
Published: September 2006

This research investigates how the term “insight” was employed in 25 decisions from mental health review proceedings in Victoria, Australia. The application of insight appears problematic in these decisions. First, there is little clarification of its meaning. Second, the logic applied when insight is related to compliance is often unclear. Third, there are frequent allusions to an implicit and undefined scale of insight, offering the appearance of objectivity. We have analysed insight as an ‘interpretive resource’, focusing on its various functions in the complex social context of commitment hearings and with a view to its therapeutic jurisprudence implications. The variable application of insight—its interpretive flexibility—appears useful in addressing complex problems faced by review boards. Hence, a key function of insight is to bridge between legal and clinical discourses. Insight is also a convenient means to avoid complicated debates regarding the person's credibility. By analysing insight in Victoria, we hope to contribute to better theoretical understanding of decision‐making patterns in mental health law in general. Copyright © 2006 John Wiley & Sons, Ltd.
The Molecular Mechanism of the Termination of Insect Diapause, Part 1: A Timer Protein, TIME‐EA4, in the Diapause Eggs of the Silkworm Bombyx mori is a Metallo‐Glycoprotein
Authors: Isobe Minoru , Kai Hidenori , Kurahashi Takuya , Suwan Sathorn , Pitchayawasin‐Thapphasaraphong Suthasinee , Franz Thomas , Tani Naoki , Higashi Kenichiro , Nishida Hideo
Published: September 2006

TIME‐EA4 is an ATPase that measures time intervals, functioning as a diapause duration clock in diapause eggs of the silkworm, Bombyx mori. Characterization of the primary and higher structures of the TIME‐EA4 would be desirable to clarify the mechanism by which the protein measures the time intervals. In our current studies, the whole sequence of TIME‐EA4 has been established as that of a metallo‐glycoprotein by combinational means involving peptide sequence analysis, nano‐HPLC–ESI‐Q‐TOF‐MS and MS/MS, and cDNA dictation. The amino acid sequence of TIME‐EA4 showed 46–55 % homology with the reported proteins of the Cu,Zn‐SOD (superoxide dismutase) family; in particular, the SOD active site (core domain) includes metal‐binding amino acid ligands and a disulfide bond, and these structures are completely identical in Bombyx SOD, bovine SOD, and TIME‐EA4 proteins. We found, however, that TIME‐EA4 contains one more copper ion than other SODs, as was proven under neutral nondenaturing conditions. ESI mass spectrometry revealed that the timer function was not in the SOD core domain. In addition, TIME‐EA4 has an attached sugar chain, which is indispensable to its functioning as a timer protein.
Silver‐Catalyzed Asymmetric Synthesis of 2,3‐Dihydrobenzofurans: A New Chiral Synthesis of Pterocarpans
Authors: Jiménez‐González Leticia , García‐Muñoz Sergio , Álvarez‐Corral Miriam , Muñoz‐Dorado Manuel , Rodríguez‐García Ignacio
Published: September 2006

2,3‐Dihydrobenzofurans can be diastereoselectively prepared by condensation of aromatic aldehydes with 2,3‐dihydrobenzoxasilepines under the catalysis of AgI complexes, and in the presence of a source of fluoride ion. The application of this strategy by using chiral catalysts leads to a new enantioselective total synthesis of natural cis‐pterocarpans and their trans isomers. Through this method, the first enantioselective total synthesis of the antifungal agent (−)‐pterocarpin was achieved. In addition, a new entry into the heteroaromatic system of 2,5‐dihydrobenzoxepine is also presented.
Energetic Bicyclic Azolium Salts
Authors: Gao Ye , Ye Chengfeng , Twamley Brendan , Shreeve Jean'ne M.
Published: September 2006

Bicyclic azoles, 2‐methyl‐5‐(imidazol‐1‐yl)‐2H‐tetrazole (1), 2‐methyl‐5‐(1,2,4‐triazol‐1‐yl)‐2H‐tetrazole (4), 1‐methyl‐5‐(imidazol‐1‐yl)‐1H‐tetrazole (7), 1‐methyl‐5‐(1,2,4‐triazol‐1‐yl)‐1H‐tetrazole (10), 1‐methyl‐4‐nitro‐2‐(imidazol‐1‐yl)‐1H‐imidazole (13), and 1‐methyl‐4‐nitro‐2‐(1,2,4‐triazol‐1‐yl)‐1H‐imidazole (16) were prepared. Their thermally stable azolium salts, 3, 6, 9, 12, 15, and 18–21, with densities ranging between 1.519–1.674 g cm−3, were synthesized by quaternization with nitric or perchloric acid or with iodomethane followed by metathesis reactions with silver nitrate and silver perchlorate. The structures of 12 b and 21 b were confirmed by single‐crystal X‐ray analysis. The standard enthalpies of formation for some of the new salts were calculated by using the computationally feasible DFT(B3LYP) and MP2 methods in conjunction with an empirical approach based on densities of salts. The calculated values range from Δ${H{{{\circ}\hfill \atop {\rm f}\hfill}}}$=209.9 (21 a) to 412.3 (12 b) kJ mol−1 in which the experimental densities are >1.515 g cm−3.
Coupling–Isomerization Synthesis of Chalcones
Authors: Braun Roland U. , Ansorge Markus , Müller Thomas J. J.
Published: September 2006

The Sonogashira coupling of electron‐deficient (hetero)aryl halides 1 and (hetero)aryl or alkenyl 1‐propargyl alcohols 2 does not terminate at the stage of the expected internal propargyl alcohols, but rather gives rise to the formation of α,β‐unsaturated ketones 3 with a variety of acceptor substituents. This new domino reaction, a coupling–isomerization reaction (CIR), can be rationalized as a sequence of rapid Pd/Cu‐catalyzed alkynylation followed by a slow amine‐base‐catalyzed propargyl alcohol–enone isomerization. Performing the CIR in deuterated protic solvents or with a selectively deuterated propargyl alcohol revealed that the base‐catalyzed isomerization step proceeds through a formal 1,3‐H shift with minimal H/D exchange with the surrounding solvent. Additionally, 19F NMR kinetic measurements on the isomerization step with the fluorinated propargyl alcohol 4 r support the mechanistic rationale.
Perylenophthalocyanines
Authors: Cammidge Andrew N. , Gopee Hemant
Published: September 2006

The first perylenophthalocyanines have been synthesised using a Diels–Alder reaction between dialkylperylenes and fumaronitrile as the key step towards the dinitrile precursors. As expected the octaalkylperylenophthalocyanines show red‐shifted absorption spectra. They are high melting solids that do not display mesophase behaviour at accessible temperatures. A 3:1 phthalocyanine/perylenophthalocyanine hybrid material, prepared by a mixed macrocyclisation reaction, presents an unusual board‐like molecular profile. Its absorption maxima lie between those observed for the parent phthalocyanines and the symmetrical perylenophthalocyanines. The spectrum shows a characteristic split Q‐band due to the reduced symmetry of the core. This material is non‐mesogenic but is sufficiently soluble to permit processing and characterisation. The 1H NMR spectrum indicates that at least two of the appended alkyl chains are displaced out of the macrocycle plane and lie in its shielding region—an arrangement that disfavours the face‐to‐face packing required for mesophase formation.
Terminally Coordinated AsS and PS Ligands
Authors: Balázs Gábor , Green Jennifer C. , Scheer Manfred
Published: September 2006

The terminal AsS and PS complexes [(N3N)W(ES)] (N3N=N(CH2CH2NSiMe3)3; E=P (3), As (4)) were synthesised by reaction of [(N3N)WAs] and [(N3N)WP], respectively, with cyclohexene sulfide. Both complexes present very short WE and ES bond lengths. The bonding was investigated by density functional theory (DFT) calculations using the fragment calculation method and natural bond orbital (NBO) analysis. According to the fragment analysis, in which the complexes were separated in an ES and a (N3N)W fragment, the bonding in complexes 3, 4 and [(N3N)W(SbS)] (5) is realised over a set of two σ (1σ and 2σ) and two degenerate π molecular orbitals (MOs) (1π and 2π). The 1σ MO is a bonding MO extended over the Nax‐W‐E‐S core, whereas the 2σ MO is localised mainly on the E–S fragment. The 1π set is a E–S localised bonding molecular orbital, whereas the 2π set is in phase with respect to W–E but in antiphase with respect to E–S. Both methods indicate bond orders around two for both the ES and the WE bonds. The polarity of the complexes was examined by Hirshfeld charge analysis. This shows that complexes 3 and 4 are only slightly polarised, whereas 5 is moderately polarised toward the sulphur. As suggested by the computational results, the π system in complexes 3–5 is best described by two three‐centre four‐electron bonds.
Aggregation of Dodecyl 1‐Pyrenylmethyl Ether and Its Application in Structure‐Polarity Relations of Aggregates†
Authors: Sang Da‐Yong , Tian Juan , Ji Guo‐Zhen
Published: September 2006

The aggregation behavior of dodecyl 1‐pyrenylmethyl ether was studied in dioxane‐water mixture solvents by fluorescence techniques. The labeled pyrenyl group was effective in monitoring the polarity change of its environment during aggregation processes. Based on the structural effects such as chain‐length effect, self‐coiling effect, and branch‐group effect on the polarity of the probe environment, the structure features of aggregates were discussed and have been used to interpret the effect of the structural features on the aggregates formed by three cholesteryl esters and three long chain alkanes.
Determination of Four Active Ingredients in Vc Yinqiao Tablets by Capillary Zone Electrophoresis with Amperometric Detection†
Authors: LÜ Jin , Wang Qing‐Jiang , Cheng Xi , Liu Hai‐Yan , He Pin‐Gang , Fang Yu‐Zhi
Published: September 2006

A simple, reliable and reproducible method, based on capillary zone electrophoresis with amperometric detection (CZE‐AD), has been developed for simultaneous determination of four active ingredients in Vc Yinqiao tablets including paracetamol, vitamin C, caffeic acid and chlorogenic acid. A carbon‐disk electrode was used as working electrode and 0.95 V (versus SCE) was selected as detection potential. The optimal conditions of CZE experiment were 30 mmol·L−1 borate solution (pH 9.5) as running buffer, 14 kV as separation voltage and 8 s (14 kV) as electro‐kinetic sampling time. Under the selected optimum conditions, paracetamol, vitamin C, caffeic acid and chlorogenic acid could be perfectly separated within 22 min, and their detection limits (S/N=3) ranged from 5×10−7 to1×10−6 mol·L−1. This proposed method demonstrated good reproducibility with relative standard deviations of less than 3% for both migration time and peak current (n=7). The utility of this method was demonstrated by monitoring a kind of compound medicine named Vc Yinqiao tablets and the assay results were satisfactory.
A New Pyrene‐Spacer‐Maleimide Dyad for Sensing Molecules with One or Two Thiol Groups†
Authors: Wang Zhuo , Zhang De‐Qing , Zhu Dao‐Ben
Published: September 2006

A new pyrene‐spacer‐maleimide dyad 1 was used to selectively detect cysteine in the presence of other amino acids, and sequentially react with dithiols to generate the molecule with two pyrene units showing typical excimer fluorescence. Accordingly, dyad 1 was able to differentiate molecules with one or two thiol groups.
A Novel Catenarian Cyano(triphenyl phosphite) Copper(I) Complex: Synthesis, Crystal Structure, Thermal, Voltammetric and Spectral Properties†
Authors: Qiao Yuan‐Biao , Wang Ke‐Fei , Hu Li‐Hong , Jian Fang‐Fang
Published: September 2006

Quantitative reaction between copper(I) cyanide and triphenyl phosphite forms copper(I) complex [(P(OPh)3)4Cu4(CN)4] (1). X‐Ray crystal structure shows a catenarian polymer of tandem interconnected copper cyanide, with C and N connecting to proximal Cu atoms. The Cu atoms adopt two different conformations:one exhibits linear construction, while the other exhibits distorted tetrahedral geometry through coordinating to two cyano groups and the P donors of triphenyl phosphite molecules. The feature of 1 is the propagation pattern of two‐ and four‐coordination along with the chain. IR and electronic absorption spectra also confirm the established single crystal structure. Thermal analysis indicates that 1 has a high thermal stability. 3‐D fluorescence result shows the middle absorption peaks with the maximum excitement and emission wavelength 342 and 350 nm, respectively. Cyclic voltammogram in DMSO, DMF and MeCN gives a midpoint voltage of −0.003, 0.061 and 0.137 V versus SCE, respectively, showing the different solvent virtue on reduction potential.
Synthesis, Characterization and Properties of Two Novel Complexes Based on 2‐Aminopyridine and Polyoxometalates†
Authors: Gong Yun , Li Yang‐Guang , Li Hui , Wang Yong‐Hui , Hu Chang‐Wen
Published: September 2006

Two novel complexes based on 2‐aminopyridine and polyoxometalates (POMs) formulated as (C5H7N2)6‐[PMo11VMoVIO40(VIVO)4]·H2O (1) and (C5H7N2)16[P2W18O61.5]2 (2) were hydrothermally synthesized and structurally characterized by elemental analysis, ICP, IR, UV‐Vis, TG, ESR and single crystal X‐ray diffraction methods. Complex 1 consists of a novel tetra‐capped Keggin POMs, [PMo11VMoVIO40(VIVO)4]6− in which four [VIVO5] square pyramids cap the equatorial positions of Keggin core [PMo11VMoVIO40]14−, linked together with six protonated 2‐aminopyridine via hydrogen bonding interactions. Dawson and lacunary Dawson POMs, [P2W18O62]6− and [P2W17O61]10− coexist in complex 2, they link together with sixteen protonated 2‐aminopyridine via hydrogen bonding interactions. Complex 2 exhibits photochromic property.
Synthesis ofC‐Aryl‐flavonoid Derivatives via Suzuki‐Miyaura Coupling Reaction†
Authors: Peng Wen‐Jie , Han Xiu‐Wen , Yu Biao
Published: September 2006

A variety of 4′‐ and 3‐C‐aryl‐quercetin derivatives were conveniently synthesized via Suzuki‐Miyaura coupling of the corresponding quercetin‐O‐triflates with aryl boronic acids or boronates.
Synthesis of Potential Inhibitiors for Stat‐3 Dimerization†
Authors: Cui Jia‐Rong , Jian Ya‐Jun , Wu Yi‐Kang , Xiao Qin
Published: September 2006

Nine bioactive ochromycinone analogues were synthesized through two different types of routes. Some unexpected products were obtained in the photo‐induced oxidation. The syntheses disclosed herein complement those in the literature and offer inexpensive access to many of the known intermediates involved, most of which were studied years ago in completely different contexts.
Synthesis of 3‐Trifluoro‐2‐hydroxy/amino‐1‐fluoropropylphosphonates†
Authors: Zheng Wei‐Hong , Yuan Cheng‐Ye
Published: September 2006

Reaction of diethyl 2,2‐difluoro‐3‐(α‐methylbenzyl)imino‐4,4,4‐trifluoropropanephosphonate (3) with triethyl‐ amine afforded a mixture of normal [1,3]‐proton shift reaction product 5 and its HF‐eliminated compound 6Z in 1:1 ratio. Upon hydrolysis, this reaction mixture gave solely 1,3,3,3‐tetrafluoro‐2‐dioxypropanephosphonate (9). Reaction of 3 with DBU provided only 6, in which the ratio of E/Z forms was dependent on the reaction conditions. Aqueous hydrolysis of 6 led to 9. Catalytic hydrogenation and hydrogenolysis of 6 gave geometric isomers of 11 as expected. The reaction mechanism involved was discussed.
N‐Unsubstituted and N‐Arylated Fulleropyrrolidines: New Useful Building Blocks for C60 Functionalization†
Authors: Tong Chen‐Hua , Wu Zong‐Quan , Hou Jun‐Li , Li Zhan‐Ting
Published: September 2006

Two series of stable and soluble fulleropyrrolidines have been prepared from the reactions of C60, glycine or its N‐arylated derivatives and aliphatic aldehydes or ketones in refluxing toluene or chlorobenzene. The new C60 derivatives represent new useful building blocks for further preparation of more funcionalized C60 derivatives.
Self‐assembly of Hydrazide‐based Heterodimers Driven by Hydrogen Bonding and Donor‐Acceptor Interaction†
Authors: Feng Dai‐Jun , Wang Peng , Li Xiao‐Qiang , Li Zhan‐Ting
Published: September 2006

A new series of hydrogen bonding‐driven heterodimers have been self‐assembled in chloroform from hydrazide‐based monomers. Additional intermolecular donor‐acceptor interaction between the electron‐rich bis(p‐phenylene)‐34‐crown‐10 unit and the electron‐deficient naphthalene diimide unit has been utilized to increase the stability of the dimmers, and pronounced cooperativity of the two discrete non‐covalent forces to stabilize the dimer has been revealed by the quantitative 1H (2D) NMR and UV‐Vis experiments.
Kinetic Evidence for the Solvent Intervention in the Solvolysis of Tertiary Benzylic Benzoates†
Authors: Liu Kwang‐Ting , Chang Lih‐Wei , Chin Chien‐Pu
Published: September 2006

Rates of solvolyses of 2‐(4‐methylphenyl)‐2‐propyl benzoate (2b), 2‐(4‐methylthiophenyl)‐2‐propyl benzoate (3b) and 2,2‐dimethyl‐1‐(4‐methoxyphenyl)‐1‐phenyl‐1‐propyl benzoate (4b) were measured, respectively, in ten or more different solvent systems. Additional YBnOPNB and YxBnOPNB values in binary trifluoroethanol‐water systems were determined. Grunwald‐Winstein type correlation analysis showed that YBnOPNB values were applicable to benzylic benzoates. The rate ratio, kOPNB/kOBz, was found to be solvent‐dependent in the range of 29 for 4 in ethanol to 4 for 2 in trifluoroethanol‐water. Non‐limiting mechanism, including both nucleophilic and electrophilic solvent assistance, in the solvolysis of 2b was discussed.
Synthesis, Structure, Thermal and Magnetic Properties of a New Open‐framework Borophosphate: NH4Mn(H2O)2BP2O8·H2O†
Authors: Shi Heng‐Zhen , Chang Jia‐Zhong , TANG‐BO He‐Jin , Ding Han‐Ming , Shan Yong‐Kui
Published: September 2006

Using new template agent, a new borophosphate compound, NH4Mn(H2O)2BP2O8·H2O was hydrothermally prepared and structurally characterized. It crystallizes in a hexagonal space group P6122 with lattice parameters a=0.9652(2) nm, c=1.5792(5) nm, V=1.2740(5) nm3 and Z=6. The structure has a three‐dimensional open‐frame work with borophosphate helical ribbons 1∞{[BP2O8]3− and MnO4(H2O)2 octahedra. The water molecules are positioned inside the helical channels. Very interestingly, the ammonium ions are located outside the loop of the free helical ribbons via the strong hydrogen bonds, which is different from the borophosphate analogue reported. The magnetization of the title compound is paramagnetic down to 5 K of the Curie‐Weiss type within the measured range of 5–300 K with ⊖=−7.3 K, indicative of very weak antiferromagnetic interactions. The thermal decomposition of the compound was also described.
Crystal Structure of an Octanuclear Sandwich Cluster of Silver(I) and 4,4′‐Bis(2,5‐dimethylstyryl)biphenyl†
Authors: Liu Shu‐Qin , Ning Gui‐Ling , Zhang Xiong‐Fu , Konaka Hisashi , Munakata Megumu
Published: September 2006

Reaction of the oligo(phenylenevinylene) 4,4′‐bis(2,5‐dimethylstyryl)biphenyl (bdb) with CF3CO2Ag in benzene gave a novel octanuclear sandwich cluster [Ag8(bdb)2(C6H6)2(CF3CO2)8]·2C6H6 (1). The clusters are packed on each other through strong π‐π interactions to form 1D ′brick′ chains, between which the solvated benzene molecules are located. TG analysis showed that cluster 1 could completely liberate the guest benzene molecules at 105 °C and the coordinated benzene molecules at 180 °C. In solid state, cluster 1 exhibits fluorescence, and the emission band is red‐shifted compared with that of free ligand bdb.
A Density Functional Study of the Hydrogenation of Ketones Catalysed by Neutral Rhodium‐Diphosphane Complexes
Authors: Agbossou‐Niedercorn Francine , Paul Jean‐François
Published: September 2006

The potential energy profile of RhI‐catalysed hydrogenation of ketones has been computed for the simple model system [Rh{H3POCH2CH2N(H)PH3}(Cl)] using DFT calculations. The general sequence of the catalytic cycle involves coordination of the carbonyl derivative to the neutral RhI complex followed by oxidative addition of molecular hydrogen providing rhodium dihydride intermediates. The latter are converted into alkoxy hydrides by a migratory insertion reaction. Reductive elimination of the alcohol and substitution of the latter by the incoming substrate completes the catalyticcycle. Intermediates and transition states of all catalyticsteps have been located. Two isomeric derivatives bearingthe model substrate have been found for the [Rh{H3POCH2CH2N(H)PH3}(Cl)(H2CO)] complex. Eight diastereomeric pathways have been followed for the cis addition of molecular hydrogen to [Rh{H3POCH2CH2N(H)PH3}(Cl)(H2CO)] leading to eight distinct isomeric dihydride intermediates. Four dihydride complexes can be considered as the more accessible compounds. The site preference for migratory insertion and transition states discriminates the main path of the catalytic reaction. Migratory insertion to form the alkoxy hydride constitute the turn over limiting step of the process. The potential energy profile has been found to be smooth without excessive activation barriers. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006)
Synthesis and Properties of Organometallic PtII and PtIV Complexes with Acyclic Selenoether and Telluroether Ligands and Selenoether Macrocycles
Authors: Levason William , Manning Joanna M. , Pawelzyk Paul , Reid Gillian
Published: September 2006

The first series of planar dimethyl(selenoether)PtII complexes, [PtMe2L] [L = MeSe(CH2)nSeMe (n = 2 or 3), o‐C6H4(CH2SeMe)2, [8]aneSe2 (1,5‐diselenacyclooctane), or [16]aneSe4 (1,5,9,13‐tetraselenacyclohexadecane)], have been obtained by treatment of [PtMe2(SMe2)2] with L in Et2O solution and characterised by VT 1H, 13C{1H}, 77Se{1H} and 195Pt{1H} NMR spectroscopy, electrospray MS and microanalysis. The corresponding dimethyl(telluroether)PtII complexes do not form under similar reaction conditions. The distorted octahedral [PtMe3I(L)] [L = o‐C6H4(CH2SeMe)2, [8]aneSe2, [16]aneSe4 or MeC(CH2SeMe)3] form as stable complexes in good yield from reaction of PtMe3I with L in refluxing CHCl3 and have been characterised similarly. These all show bidentate selenoether coordination, with fast pyramidal inversion occurring at room temperature. The distorted octahedral coordination environment at PtIV is also confirmed from a crystal structure of [PtMe3I{o‐C6H4(CH2SeMe)2}]. Rare examples of (telluroether)PtIV complexes, [PtMe3I{o‐C6H4(CH2TeMe)2}] and the dinuclear [Me3Pt(μ2‐I)2(μ2‐MeTeCH2TeMe)PtMe3], have also been prepared and characterised similarly (and also by 125Te{1H} NMR spectroscopy). The [8]aneSe2 and [16]aneSe4 species are the first examples of alkyl PtII or PtIV complexes with (macro)cyclic selenoether coordination. Halide abstraction (TlPF6) from [PtMe3I(κ2‐[16]aneSe4)] affords [PtMe3(κ3‐[16]aneSe4)]PF6; a rare example of a cationic PtIV selenoether. The (diselenoether)PtII complexes undergo oxidative addition of MeI to yield the corresponding PtIV species [PtMe3I(diselenoether)]. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006)
Click Chemistry with an Active Site Variant of Azurin
Authors: de Jongh Thyra E. , van Roon Anne‐Marie M. , Prudêncio Miguel , Ubbink Marcellus , Canters Gerard W.
Published: September 2006

The active site of the blue copper protein azurin (Azu) from Pseudomonas aeruginosa consists of a Cu ion immobilized by bonds to four amino acid side chains. The protein assists in electron transfer in vivo. Replacement of Cu‐ligand His117 by a Gly makes the Cu site accessible for exogenous ligands. Incubation of the H117G Azu with n‐alkane linkers carrying imidazole groups at opposite ends leads to the formation of noncovalently linked Azu dimers. The active site of H117G Azu is vulnerable to Cu‐catalyzed oxidative attack. Replacement of CuII by ZnII leads to stable dimers, whose structures have been determined by X‐ray diffraction. These structures are reported here. The similarity in the structure of the active site between the wild type (wt) Zn‐Azu and the dimer is remarkable in light of the different relation of the coordinating imidazole to the protein framework (covalently attached vs. exogenous origin, respectively). The part of the “ligand loop” running from amino acid 116 to 121 has acquired increased flexibility in the mutant. The connected subunits have adopted an unexpected orientation relative to each other.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006)
Synthetic Studies on Cyathin Terpenoids: Enantioselective Synthesis of the Tricyclic Core of Cyathin through Intramolecular Heck Cyclisation
Authors: Drège Emmanuelle , Tominiaux Cyrille , Morgant Georges , Desmaële Didier
Published: September 2006

An enantioselective synthesis of the tricyclic ketone (+)‐5, which displays the carbon core of NGF‐inducing cyathane diterpenes, has been completed according to a strategy in which the key step was the intramolecular Heck reaction of the AC subunit 49 establishing the crucial anti stereochemical relationship between the two angular substituents. The C‐9 quaternary centre was set up by taking advantage of the enantioselective Michael addition involving chiral imines providing keto ester (R)‐10 in 91 % ee. After incorporation of the isopropyl group and iododecarboxylation of the propionate side chain, the iodo ketone 39 was condensed with the lithium enolate of methyl dihydrobenzoate to give the AC subunit 43 which was further elaborated to triflate (–)‐22. While direct Heck cyclisation of 22 was ineffective, oxidation of the bis(allylic) position of the 1,4‐cyclohexadiene moiety enhanced the reactivity, allowing the stereoselective formation of the hexahydro‐cyclopenta[a]naphthalene (+)‐50a. A key element of the construction was the final C ring enlargement, involving trimethylaluminum‐promoted one‐carbon expansion of ketone 52 with trimethylsilyldiazomethane which provided the tricyclic ketone (+)‐5. Furthermore, epoxidation of trienone (+)‐50a was shown to occur exclusively on the β face, giving rise to the C‐14 functionalised advanced intermediate 51 which has considerable potential for the synthesis of natural cyathins and analogues.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006)
Superacidic Activation of Maleimide and Phthalimide and Their Reactions with Cyclohexane and Arenes
Authors: Koltunov Konstantin Yu. , Prakash G. K. Surya , Rasul Golam , Olah George A.
Published: September 2006

When activated in the CF3SO3H/SbF5 acid system maleimide (1) and phthalimide (2) undergo selective ionic hydrogenation with cyclohexane to give 1,5‐dihydropyrrol‐2‐one (3) and phthalimidine (11), respectively. When treated with aluminum halides, N‐phenylmaleimide (4) reacts with cyclohexane to give N‐phenylsuccinimide (5), whereas 2 still gives 11. Imide 1 also condenses with benzene in trifluoromethanesulfonic acid (CF3SO3H) to give 1,5‐dihydro‐5,5‐diphenylpyrrol‐2‐one (7) as the major product. However, in the presence of aluminum halides 1 reacts with benzene, toluene, and o‐dichlorobenzene to give 3‐arylsuccinimides 8–10, respectively. Imide 2 reacts with benzene under the influence of trifluoromethanesulfonic acid as well as aluminum halides to yield 3,3‐diphenylphthalimidine (12). The mechanism of these reactions, with potential involvement of superelectrophilic dicationic intermediates, is discussed. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006)
Rhodium‐Catalyzed Hydroboration Reactions with Sulfur and Nitrogen Analogues of Catecholborane
Authors: Hadebe Siphamandla W. , Robinson Ross S.
Published: September 2006

Rhodium‐catalyzed hydroboration of 1‐octene and trans‐4‐octene with sulfur‐ and nitrogen analogues of catecholborane are demonstrated with the use of in situ 11B NMR spectroscopy. Our study shows that the sulfur‐ and nitrogen analogues are significantly less prone to disproportionation than catechol, which results in enhanced yields of the desired compounds.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006)
Interactions between sediment delivery, channel change, climate change and flood risk in a temperate upland environment
Authors: Lane S. N. , Tayefi V. , Reid S. C. , Yu D. , Hardy R. J.
Published: September 2006

This paper uses numerical simulation of flood inundation based on a coupled one‐dimensional–two‐dimensional treatment to explore the impacts upon flood extent of both long‐term climate changes, predicted to the 2050s and 2080s, and short‐term river channel changes in response to sediment delivery, for a temperate upland gravel‐bed river. Results show that 16 months of measured in‐channel sedimentation in an upland gravel‐bed river cause about half of the increase in inundation extent that was simulated to arise from climate change. Consideration of the joint impacts of climate change and sedimentation emphasized the non‐linear nature of system response, and the possibly severe and synergistic effects that come from combined direct effects of climate change and sediment delivery. Such effects are likely to be exacerbated further as a result of the impacts of climate change upon coarse sediment delivery. In generic terms, these processes are commonly overlooked in flood risk mapping exercises and are likely to be important in any river system where there are high rates of sediment delivery and long‐term transfer of sediment to floodplain storage (i.e. alluviation involving active channel aggradation and migration). Similarly, attempts to reduce channel migration through river bank stabilization are likely to exacerbate this process as without bank erosion, channel capacity cannot be maintained. Finally, many flood risk mapping studies rely upon calibration based upon combining contemporary bed surveys with historical flood outlines, and this will lead to underestimation of the magnitude and frequency of floodplain inundation in an aggrading system for a flood of a given magnitude. Copyright © 2006 John Wiley & Sons, Ltd.
Are forecasters reluctant to revise their predictions? Some German evidence
Authors: Kirchgässner Gebhard , Müller Ulrich K.
Published: September 2006

People are reluctant to admit mistakes. This could also be true of economic forecasters. If revisions of past forecasts are costly, then it will become optimal for forecasters to only partially adjust a past forecast in the light of new information. The unwillingness to admit to the mistake in the old forecast generates a bias of the new forecast in the direction of the old forecast. We test this hypothesis for the joint predictions of the Association of German Economic Research Institutes over the last 35 years. We find some evidence for such a bias and compute the implied unwillingness to revise forecasts.  Copyright © 2006 John Wiley & Sons, Ltd.
A de novo MLH1 germ line mutation in a 31‐year‐old colorectal cancer patient
Authors: Plasilova Martina , Zhang Jian , Okhowat Roberta , Marra Giancarlo , Mettler Markus , Mueller Hansjakob , Heinimann Karl
Published: September 2006

Hereditary nonpolyposis colorectal cancer is an autosomal dominant cancer predisposition syndrome caused by inherited germ line mutations in DNA mismatch repair genes, predominantly MSH2 and MLH1. Here we report the first proven de novo germ line mutation in MLH1 (c.666dupA) identified in a 31‐year‐old colorectal cancer patient with the alteration being present in a heterozygous state in all three germ layers and homozygously in his colon cancer. The mutation was absent in both biological parents and all sibs available. Despite extensive polymorphic marker analysis, the parental origin of c.666dupA could not be conclusively determined, representing either a single mutational event in a parental germ cell or (maternal) gonadal mosaicism. Although rare, consequential application of the Bethesda guidelines for genetic testing should allow the clinician to readily identify colorectal cancer patients below age 50 years who carry de novo mismatch repair gene mutations. © 2006 Wiley‐Liss, Inc.
Detection in primary chronic myeloid leukaemia cells of p210BCR‐ABL1 in complexes with adaptor proteins CBL, CRKL, and GRB2
Authors: Patel Hetal , Marley Stephen B. , Gordon Myrtle Y.
Published: September 2006

Chronic myeloid leukemia (CML) arises as a consequence of the expression of a chimeric fusion protein, p210BCR‐ABL1, which is localized to the cytoplasm and has constitutive protein tyrosine kinase activity. Extensive publications report that p210BCR‐ABL1 complexed with multiple cytoplasmic proteins can modulate several cell signaling pathways. However, while altered signaling states can be demonstrated in primary CML material, most of the reported analytical work on complexed proteins has been done in cell lines expressing p210BCR‐ABL1. This has been necessary because primary hemopoietic cell lysates contain a degradative activity which rapidly and permanently destroys p210BCR‐ABL1, precluding accurate p210BCR‐ABL1 quantification by Western blotting or investigation of coimmunoprecipitating proteins in primary cells. This degradative activity has proven intractable to inhibition by conventional protease inhibitors. We show here that the degradative activity in primary cells is associated with cell lysosomes and is most likely to be an acid‐dependent hydrolase. By lysing primary hemopoietic cells at high pH, we have demonstrated substantial inhibition of the p210BCR‐ABL1‐degradative activity and now report, to the best of our knowledge, the first published demonstration by coimmunoprecipitation of the association between p210BCR‐ABL1 and cytoplasmic effector proteins in primary CML material. © 2006 Wiley‐Liss, Inc.
On Board the Maria S. Merian
Authors: Neutzling Anja
Published: September 2006

The maiden voyage of the Maria S. Merian: On its first expedition the new ice‐margin research vessel set course for the northernmost reaches of the Baltic
Top Priority: Innovation
Authors: Oetker Arend
Published: September 2006

Germany needs interaction between science and business as well as an advocate for basic research – an independent view
How Our Climate Is Influenced by Soils
Authors: Kögel‐Knabner Ingrid , v. Lützow Margit
Published: September 2006

The latest news on old matter: Four‐fifths of the globe's carbon reserves are stored in its soil. Humus not only has a large impact on soil functions; it is also important in the global carbon cycle, which influences climate
Predicting the onset of major depressive disorder and dysthymia in older adults with subthreshold depression: a community based study
Authors: Cuijpers Pim , Beekman Aartjan , Smit Filip , Deeg Dorly
Published: September 2006

Background

It is well‐established that the incidence of major depressive disorder is increased in subjects with subthreshold depression. A new research area focuses on the possibilities of preventing the onset of major depressive disorders in subjects with subthreshold depression. An important research question for this research area is which subjects with subthreshold depression will develop a full‐blown depressive disorder and which will not.

Methods

We selected 154 older subjects with subthreshold depression (CES‐D > 16) but no DSM mood disorder from a longitudinal study among a large population based cohort aged between 55 and 85 years in The Netherlands. Of these subjects, 31 (20.1%) developed a mood disorder (major depression and/or dysthymia) at three‐year or six‐year follow‐up. We examined risk factors and individual symptoms of mood disorder as predictors of onset of mood disorder.

Results

Two variables were found to be significant predictors in both bivariate and multivariate analyses: eating problems and sleep problems. The incidence of mood disorders differed strongly for different subpopulations, varying from 9% (for those not having any of the two risk factors) to 57% (for those having both risk factors).

Conclusions

It appears to be possible to predict to a certain degree whether a subject with subthreshold depression will develop a mood disorder during the following years. Copyright © 2006 John Wiley & Sons, Ltd.
Processing of emotionally toned pictures in dementia
Authors: Eling P. A. T. M. , Maes J. H. R. , Van Haaf M.
Published: September 2006

Background

Apathy is a common symptom in dementia and is often associated with reduced emotional reactivity. This study examined whether reduced emotional reactivity can be demonstrated in dementia patients using a picture viewing task.

Methods

The viewing time of three different types of visual stimuli was measured in 24 elderly participants, half of which suffered from dementia. The participants had to make a target response to an emotionally neutral target stimulus that was intermixed with a frequently occurring non‐target or ‘background’ stimulus and infrequently presented emotional stimuli. All participants could control the presentation time of each stimulus, but one half of the participants were explicitly instructed to perform the task quickly.

Results

The main measure was a ratio score in which the viewing time for emotional stimuli was expressed relative to the viewing time for the neutral non‐target stimulus. Using this measure, the instigation of a time‐pressure condition proved to significantly reduce the viewing time for emotional stimuli in the healthy subjects. Irrespective of time‐pressure condition, the dementia patients showed a similar short viewing time for emotional stimuli as did the healthy subjects in the time‐pressure condition. However, both dementia patients and healthy controls displayed longer viewing times for unpleasant than for pleasant stimuli.

Conclusion

These results suggest the ability of the present task to reveal the simultaneous occurrence of an overall reduced interest for novel stimuli and an intact differential emotional reactivity to stimuli with a negative versus positive valence in the dementia patients. Copyright © 2006 John Wiley & Sons, Ltd.
A preliminary study of the diagnostic accuracy of the Gerontological Personality disorders Scale (GPS)
Authors: van Alphen S. P. J. , Engelen G. J. J. A. , Kuin Y. , Hoijtink H. J. A. , Derksen J. J. L.
Published: September 2006

Background

There is still a lack of diagnostic instruments that are specifically developed to diagnose personality disorders in the elderly.

Objective

To develop a reliable and valid screening instrument to assess personality disorders in older adults.

Method

The draft version of the screening instrument (52 items) consists of two sections: one for patients and one for informants. The diagnostic accuracy of the instrument has been assessed in the Netherlands in 159 elderly patients in an ambulatory department of geriatric psychiatry and 96 informants.

Results

In the patient section, sixteen items had a reasonable score for both sensitivity and specificity (approx. 70%). The internal consistency was moderate for habitual behavior (HAB; 7 items) and good for biographical information (BIO; 9 items). The test and retest reliability was moderate for HAB and excellent for BIO. The informant section, on the other hand, had a low score for sensitivity (45%) and a good score for specificity (78%).

Conclusion

A specific instrument has been developed to diagnose personality disorders in older adults. However, further research is necessary to improve the diagnostic accuracy of the Gerontological Personality disorders Scale (GPS). Copyright © 2006 John Wiley & Sons, Ltd.