bluuebunny/crossref_metadata_2025 huggingface dataset:
Immersion Autometallography: Histochemical In Situ Capturing of Zinc Ions in Catalytic Zinc-Sulfur Nanocrystals
Authors: Danscher Gorm , Stoltenberg Meredin , Bruhn Mikkel , Søndergaard Chris , Jensen Dorete
Published: November 2004

In the mid-1980s, two versions of Timm's original immersion sulfide silver method were published. The authors used immersion of tissue in a sulfide solution as opposed to Timm, who used immersion of tissue blocks in hydrogen sulfide-bubbled alcohol. The autometallography staining resulting from the “sulfide only immersion” was not particularly impressive, but the significance of this return to an old approach became obvious when Wenzel and co-workers presented their approach in connection with introduction by the Palmiter group of zinc transporter 3 (ZnT3). The Wenzel/Palmiter pictures are the first high-resolution, high-quality pictures taken from tissues in which free and loosely bound zinc ions have been captured in zinc-sulfur nanocrystals by immersion. The trick was to place formalin-fixed blocks of mouse brains in a solution containing 3% glutaraldehyde and 0.1% sodium sulfide, ingredients used for transcardial perfusion in the zinc-specific NeoTimm method. That the NeoTimm technique results in silver enhancement of zinc-sulfur nanocrystals has been proved by proton-induced X-ray multielement analyses (PIXE) and in vivo chelation with diethyldithiocarbamate (DEDTC). The aims of the present study were (a) to make the immersion-based capturing of zinc ions in zinc-sulfur nanocrystals work directly on sections and slices of fixed brain tissue, (b) to work out protocols that ensure zinc specificity and optimal quality of the staining, (c) to apply “immersion autometallography” (iZnSAMG) to other tissues that contain zinc-enriched (ZEN) cells, and (d) to make the immersion approach work on unfixed fresh tissue.
Immunolocalization of Actin in Paramecium Cells
Authors: Kissmehl Roland , Sehring Ivonne M. , Wagner Erika , Plattner Helmut
Published: November 2004

We have selected a conserved immunogenic region from several actin genes of Paramecium, recently cloned in our laboratory, to prepare antibodies for Western blots and immunolocalization. According to cell fractionation analysis, most actin is structure-bound. Immunofluorescence shows signal enriched in the cell cortex, notably around ciliary basal bodies (identified by anti-centrin antibodies), as well as around the oral cavity, at the cytoproct and in association with vacuoles (phagosomes) up to several μm in size. Subtle strands run throughout the cell body. Postembedding immunogold labeling/EM analysis shows that actin in the cell cortex emanates, together with the infraciliary lattice, from basal bodies to around trichocyst tips. Label was also enriched around vacuoles and vesicles of different size including “discoidal” vesicles that serve the formation of new phagosomes. By all methods used, we show actin in cilia. Although none of the structurally well-defined filament systems in Paramecium are exclusively formed by actin, actin does display some ordered, though not very conspicuous, arrays throughout the cell. F-actin may somehow serve vesicle trafficking and as a cytoplasmic scaffold. This is particularly supported by the postembedding/EM labeling analysis we used, which would hardly allow for any large-scale redistribution during preparation.
Characterization of Vascular Endothelial Growth Factor (VEGF) in the Uterine Cervix over Pregnancy: Effects of Denervation and Implications for Cervical Ripening
Authors: Mowa C.N. , Jesmin S. , Sakuma I. , Usip S. , Togashi H. , Yoshioka M. , Hattori Y. , Papka R.
Published: November 2004

Bilateral neurectomy of the pelvic nerve (BLPN) that carries uterine cervix-related sensory nerves induces dystocia, and administration of its vasoactive neuropeptides induces changes in the cervical microvasculature, resembling those that occur in the ripening cervix. This study was designed to test the hypothesis that (a) the cervix of pregnant rats expresses vascular endothelial growth factor (VEGF) and components of the angiogenic signaling pathway [VEGF receptors (Flt-1, KDR), activity of protein kinase B, Akt (phosphorylated Akt), and endothelial nitric oxide synthase (eNOS)] and von Willebrand Factor (vWF) and that these molecules undergo changes with pregnancy, and (b) bilateral pelvic neurectomy (BLPN) alters levels of VEGF concentration in the cervix. Using RT-PCR and sequencing, two VEGF isoforms, 120 and 164, were identified in the rat cervix. VEGF, VEGF receptor-1 (Flt-1), eNOS, and vWF immunoreactivities (ir) were localized in the microvasculature of cervical stroma. Their protein levels increased during pregnancy but decreased to control levels by 2 days postpartum. VEGF receptor-2 (KDR)-ir was confined to the epithelium of the endocervix. BLPN downregulated levels of VEGF by a third. Therefore, the components of the angiogenic signaling pathway are expressed in the cervix and change over pregnancy. Furthermore, angiogenic and sensory neuronal factors may be important in regulating the dynamic microvasculature in the ripening cervix and may subsequently play a role in cervical ripening and the birth process.
Proteomic Fingerprints for Potential Application to Early Diagnosis of Severe Acute Respiratory Syndrome
Authors: Kang Xixiong , Xu Yang , Wu Xiaoyi , Liang Yong , Wang Chen , Guo Junhua , Wang Yajie , Chen Maohua , Wu Da , Wang Youchun , Bi Shengli , Qiu Yan , Lu Peng , Cheng Jing , Xiao Bai , Hu Liangping , Gao Xing , Liu Jingzhong , Wang Yiping , Song Yingzhao , Zhang Liqun , Suo Fengshuang , Chen Tongyan , Huang Zeyu , Zhao Yunzhuan , Lu Hong , Pan Chunqin , Tang Hong
Published: November 2004

Background: Definitive early-stage diagnosis of severe acute respiratory syndrome (SARS) is important despite the number of laboratory tests that have been developed to complement clinical features and epidemiologic data in case definition. Pathologic changes in response to viral infection might be reflected in proteomic patterns in sera of SARS patients.

Methods: We developed a mass spectrometric decision tree classification algorithm using surface-enhanced laser desorption/ionization time-of-flight mass spectrometry. Serum samples were grouped into acute SARS (n = 74; <7 days after onset of fever) and non-SARS [n = 1067; fever and influenza A (n = 203), pneumonia (n = 176); lung cancer (n = 29); and healthy controls (n = 659)] cohorts. Diluted samples were applied to WCX-2 ProteinChip arrays (Ciphergen), and the bound proteins were assessed on a ProteinChip Reader (Model PBS II). Bioinformatic calculations were performed with Biomarker Wizard software 3.1.1 (Ciphergen).

Results: The discriminatory classifier with a panel of four biomarkers determined in the training set could precisely detect 36 of 37 (sensitivity, 97.3%) acute SARS and 987 of 993 (specificity, 99.4%) non-SARS samples. More importantly, this classifier accurately distinguished acute SARS from fever and influenza with 100% specificity (187 of 187).

Conclusions: This method is suitable for preliminary assessment of SARS and could potentially serve as a useful tool for early diagnosis.
N-Terminal Pro-B-Type Natriuretic Peptide as an Indicator of Possible Cardiovascular Disease in Severely Obese Individuals: Comparison with Patients in Different Stages of Heart Failure
Authors: Hermann-Arnhof Katharina-Maria , Hanusch-Enserer Ursula , Kaestenbauer Thomas , Publig Thomas , Dunky Attila , Rosen Harald R , Prager Rudolf , Köller Ursula
Published: November 2004

Background: Mild stages of heart failure might be difficult to diagnose in severely obese individuals with a body mass index (BMI) >40 kg/m2. Measurement of the N-terminal fragment of pro-B-type natriuretic peptide (NT-proBNP) is feasible for detecting cardiac impairment. The aims of our study were to measure NT-proBNP in plasma of severely obese patients and to compare the results with results for patients in different stages of manifest cardiac dysfunction.

Methods: In 61 severely obese individuals (median BMI, 43.2 kg/m2) and 96 nonobese patients with existing heart failure [classified into New York Heart Association (NYHA) classes I–IV], NT-proBNP was measured in the fasting condition. A medical history, physical examination, electrocardiography, blood chemistry, and chest x-ray were performed in the obese group. In addition, echocardiography was performed in the NYHA group.

Results: In obese individuals, NT-proBNP was increased to a median of 356 (interquartile range, 221–458) pmol/L [854 (530–1099) ng/L] and was comparable (P >0.05) to the median value for NYHA I patients {289 (258–451) pmol/L [694 (619–1082) ng/L]}, but was significantly lower than in the other NYHA groups (P <0.001 for each).

Conclusion: The prognostic relevance of increased NT-proBNP for risk of developing cardiac insufficiency in severely obese patients needs to be further evaluated.
India's Role in Nepal's Maoist Insurgency
Authors: Mishra Rabindra
Published: November 2004

This article examines India-Nepal relations, namely, India's role in Nepal's ongoing Maoist insurgency. It argues that the insurgency's trajectory is heavily influenced by transboundary links and should be viewed in the context of India's role in shaping the past 50 years of Nepal's political history.
Politics and Judiciary Verdicts on Vote-Buying Litigation in Taiwan
Authors: Wu Chung-li , Huang Chi
Published: November 2004

Widespread vote buying is a major characteristic of Taiwan's election politics. We examine the impact of political factors (including partisanship, whether persons are elected or not, and type of election) on court decisions at three levels for vote-buying litigation in southwestern Taiwan between 1990 and 1999. Findings reveal that political variables have considerably less effect than expected on trial outcomes.
Silenced Reality: Power Relations between Marital Blueprints in Israeli Marriages
Authors: Benjamin Orly , Ha'elyon Hila
Published: November 2004

In this study we examined the effect of job insecurity on couples' relationships in the context of recent macro‐level economic changes in Israel. Based on Hajer's discourse interaction approach, we conceptualized marital relationships and particularly the marital conversation as contested terrain reflecting power relations between social forces and their related discourses. We interviewed seventeen couples in which at least one of the partners suffered from job insecurity in order to trace forms of emotion work and silence in their marital interaction. We found that couples experienced a decreased ability to speak with each other. In their accounts of this experience, gendered “story lines” that we interpreted as “new” to the relationship emerged. Women's emotion work was indicative and halted change‐directed marital negotiation. The possibility that authoritative gendered relationships are reinforced in Israeli marriages during times of job insecurity is thus supported.
Anatomy of Fear: Mead's Theory of the Past and the Experience of the HIV/AIDS “Worried Well”
Authors: Lombardo Anthony P.
Published: November 2004

The HIV/AIDS “worried well”—persons who believe themselves infected with HIV in the absence of any objective medical proof—have been well documented in the psychological literature but not the sociological literature. Adopting a symbolic interactionist perspective, I use George Herbert Mead's theory of the past to conceptualize the HIV/AIDS worried well experience by analyzing narratives written by persons who have been worried well. Empirically, I provide sociological evidence of the existence of the HIV/AIDS worried well. Theoretically, I expand concepts derived from studies of persons with chronic illness to the worried well and speak to the influence of Mead's theory of the past to sociology.
The Experience of Living With Fibromyalgia: Confronting an Invisible Disability
Authors: Sturge-Jacobs Marilyn
Published: November 2004

Fibromyalgia (FM) is a complex, chronic, painful musculoskeletal syndrome which is characterized by extreme fatigue, disordered sleep, and other associated physical and cognitive problems. Because its etiology is unknown, and because no specific pathophysiological mechanisms have been found to underlie the syndrome, making a diagnosis is very difficult. FM adversely affects the quality of life, and the societal costs based on medical expenses, lost wages, lost tax revenue and compensation expenditures are very significant. The purpose of this phenomenological study was to describe and enhance the understanding of the experience of living with FM. The participants included nine women ranging in age from 30 years to 56 years who had been diagnosed with the condition for more than a year. Data were collected by means of unstructured interviews. Thematic analysis, using van Manen’s (1990) methodology, identified eight themes: (a) pain—the constant presence, (b) fatigue—the invisible foe, (c) sleep—the impossible dream, (d) thinking of a frog (e) dealing with a flare-up, (f) longing for a normal life, (g) the power of naming—seeking a diagnosis, and (h) living within the boundaries. These themes were integral parts of the whole story, and through their interrelationships, the essence confronting an invisible disability was captured. The findings of this qualitative study have implications for nursing practice, education and research. It has become an increasing challenge for our health care system to adequately cope with the large numbers of persons diagnosed with chronic illnesses. Administrators of these systems can benefit from the information learned during this study. cope.
Health Promotion With Adolescents: Examining Theoretical Perspectives to Guide Research
Authors: Montgomery Kristen S.
Published: November 2004

A guiding theoretical framework in research serves not only to guide a single research study, but also to link previous and future research that is guided by the same framework. Existing theoretical perspectives appropriate for use with adolescent health promotion research were reviewed. Instead of randomly selecting several theories for comparison, an intensive review of the literature was conducted to identify which theories were most commonly used with adolescent health promotion research. The results of this review revealed some interesting and noteworthy information regarding the state of theory use in adolescent health research for the last decade. Information is provided on theoretical perspectives by journal and year of publication. Trends are analyzed so that nurses can evaluate the current state of the science. Social cognitive theory (Bandura, 1986), the health belief model (Becker, 1978), and the health promotion model (Pender, 1996) emerged as the most significant theories for adolescent health promotion research and thus are discussed at the end of the article.
The Medication Adherence Model: A Guide for Assessing Medication Taking
Authors: Johnson Mary Jayne
Published: November 2004

The Medication Adherence Model (MAM) was developed to describe the process of medication adherence and guide health care providers in assessing medication-taking in individuals with hypertension. The MAM was structured with the idea that two types of nonadherence contribute to inconsistent medication taking, the intentional decision to miss medications, and the unintentional interruptions that cause medications not to be taken. The three core concepts identified in the model are: (a) Purposeful Action, (b) Patterned Behavior, and (c) Feedback. Patients’ initiating and sustaining medication adherence are dependent on the deliberate decision to take medications based on perceived need, effectiveness, and safety (Purposeful Action). Then they establish medication-taking patterns through access, routines, and remembering (Patterned Behavior). Individuals use information, prompts, or events (Feedback) during the appraisal process to evaluate health treatment that, in return, influences individuals’ levels of Purposeful Action and Patterned Behavior (Johnson, 2002; Johnson, Williams, & Marshall, 1999). The MAM depicts the dynamic process of initiating and maintaining medication adherence from the hypertensive patient’s perspective. The model describes the key components of existing cognitive and self-regulatory models, and identifies an additional behavioral component. The succinct organization of the MAM may facilitate health care providers’ ability to evaluate and individualize interventions for promoting medication taking.
The Underrepresentation of Hispanics/Latinos in Nursing Education: A Deafening Silence
Authors: Taxis Carole J.
Published: November 2004

While our national population is growing more ethnically and racially diverse, the nursing workforce and faculty remains predominantly White (non-Hispanic). Ethnic/racial minorities are seriously underrepresented in nursing and, as such, are a factor in the nursing workforce shortage. The nursing literature has addressed the need for ethnic/racial diversity for several decades, most often citing diversification as a means of providing culturally competent care. However the fact remains that the nursing population continues to be underrepresented by people of color. The diversification of the nursing profession will require culturally sensitive research and theory development regarding the recruitment and education of ethnic/racial minorities. While there is a growing body of knowledge regarding the educational needs and experiences of minorities in nursing education, much of this data generalize minorities as if they were a homogeneous group. There is a striking paucity of research regarding the underrepresentation of Hispanics in nursing and the unique issues of recruitment and retention of this group in nursing education. This paper provides a review of the mostly anecdotal literature regarding the experiences of Hispanics in nursing education. It explores the underrepresentation and paucity of culturally specific knowledge regarding the recruitment, retention, and graduation of Hispanics/Latinos in nursing. The homogeneity of nursing and its consequences specifically in relation to Hispanics is discussed. The research implications are highlighted throughout.
Potential role of the ventilation and perfusion (V/Q) lung scan in the diagnosis of acute chest syndrome in adults with sickle cell disease
Authors: Kaur Navleen , Motwani Bharat , Sivasubramaniam Devaki , Feldman Lori , Allen Sandra , Ferguson Richard , Shiomoto Gail , Ansell David , Westerman Maxwell , Feldman Lawrence
Published: November 2004

The current criteria for diagnosing ACS are chest pain and presence of a new infiltrate on the chest radiograph (CXR). This study was designed to evaluate the role of ventilation and perfusion (V/Q) scan to assist in the early diagnosis of ACS. An abnormal V/Q scan was associated with a diagnosis of ACS that reached a statistical significance (P < 0.038). The sensitivity and specificity were found to be 60% and 100%, respectively. We conclude that V/Q scan may play a role in the early diagnosis of ACS. Am. J. Hematol. 77:407–409, 2004. © 2004 Wiley‐Liss, Inc.
Type I Gaucher disease with severe skeletal destruction, extraosseous extension, and monoclonal gammopathy
Authors: Kaloterakis A. , Cholongitas E. , Pantelis E. , Papadimitriou C. , Durakis Sp. , Filiotou A.
Published: November 2004

Extraosseous extensions of Gaucher‐cell deposits simulate malignant diseases. We describe a 65‐year‐old male with type‐I Gaucher disease, confirmed by low leukocyte glucocerebrosidase activity, high plasma chitotriosidase, and N370/L444P gene‐mutations, who had severe skeletal involvement, IgG‐κ monoclonal gammopathy, and a soft‐tissue mass within the left iliac muscle. Bone marrow biopsy showed heavy infiltration by Gaucher cells, and histopathology of the excised extraosseous mass revealed infiltration by Gaucher cells. Thus, malignant diseases were excluded and the diagnosis of an extraosseous Gaucher‐cell extension was well documented. Our case is reported because it is very interesting and unique in the literature. Am. J. Hematol. 77:377–380, 2004. © 2004 Wiley‐Liss, Inc.
Human T‐cell lymphotropic virus type 1 (HTLV‐1) and lymphoid malignancies in Dominica: A seroprevalence study
Authors: Adedayo Olayinka A. , Shehu Sani M.
Published: November 2004

Human T‐cell lymphotropic virus type 1 (HTLV‐1) is endemic in certain regions of the world where it is associated with lymphoid malignancies. Herein we aim to describe the seroprevalence of HTLV‐1 in lymphoid malignancies in Dominica. We carried out a 10‐year retrospective study of histologically proven hematologic malignancies and HTLV‐1 seropositivity at the Princess Margaret Hospital, Dominica. Ninety‐eight cases were reviewed (59% males, 41% females), ranging in age from 3 to 91 years. HTLV‐1 was seropositive in 38.6% (31/80) of all hematologic malignancies. Three of 6 cases of Hodgkin disease (50%), 16 of 36 (44.4%) of non‐Hodgkin lymphoma, and 3 out of 8 unclassified lymphomas (37.5%) were seropositive; all 6 cases (100%) of acute adult T‐cell leukemia/lymphoma (ATLL) were seropositive. One case each of chronic lymphocytic leukemia and myeloproliferative disorder was seropositive. HTLV‐1‐seropositive lymphomas presented at a younger age than did seronegative cases. Thus, HTLV‐1 is significantly associated with lymphoid malignancies in Dominica, and further studies are needed before a causal relationship with Hodgkin disease can be established. Am. J. Hematol. 77:336–339, 2004. © 2004 Wiley‐Liss, Inc.
Reducing attenuation in exposure‐response relationships by exposure modeling and grouping: The relationship between wood dust exposure and lung function
Authors: Teschke Kay , Spierings Judith , Marion Stephen A. , Demers Paul A. , Davies Hugh W. , Kennedy Susan M.
Published: November 2004

Background

In a study of wood dust exposure and lung function, we tested the effect on the exposure–response relationship of six different exposure metrics using the mean measured exposure of each subject versus the mean exposure based on various methods of grouping subjects, including job‐based groups and groups based on an empirical model of the determinants of exposure.

Methods

Multiple linear regression was used to examine the association between wood dust concentration and forced expiratory volume in 1s (FEV1), adjusting for age, sex, height, race, pediatric asthma, and smoking.

Results

Stronger point estimates of the exposure–response relationships were observed when exposures were based on increasing levels of aggregation, allowing the relationships to be found statistically significant in four of the six metrics. The strongest point estimates were found when exposures were based on the determinants of exposure model.

Conclusions

Determinants of exposure modeling offers the potential for improvement in risk estimation equivalent to or beyond that from job‐based exposure grouping. Am. J. Ind. Med. 46:663–667, 2004. © 2004 Wiley‐Liss, Inc.
Astrophysical supplements to the ASCC‐2.5. II. Membership probabilities in 520 Galactic open cluster sky areas
Authors: Kharchenko N. V. , Piskunov A. E. , Röser S. , Schilbach E. , Scholz R.‐D.
Published: November 2004

We present a catalogue (CSOCA) of stars residing in 520 Galactic open cluster sky areas which is the result of the kinematic (proper motion) and photometric member selection of stars listed in the homogeneous All‐sky Compiled Catalogue of 2.5Million Stars (ASCC‐2.5).We describe the structure and contents of the catalogue, the selection procedure applied, and the proper motion and photometric membership constraints adopted. In every cluster area the CSOCA contains the complete list of the ASCC‐2.5 stars regardless of their membership probability. For every star the CSOCA includes accurate J2000 equatorial coordinates, proper motions in the Hipparcos system, BV photometric data in the Johnson system, proper motion and photometric membership probabilities, as well as angular distances from the cluster centers for about 166 000 ASCC‐2.5 stars. If available, trigonometric parallaxes, spectral types, multiplicity and variability flags from the ASCC‐2.5, and radial velocities with their errors from the Catalogue of Radial Velocities of Galactic Stars with high precision Astrometric Data (CRVAD) are also given. (© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Genetic modules and networks for behavior: lessons from Drosophila
Authors: Anholt Robert R.H.
Published: November 2004

Behaviors are quantitative traits determined through actions of multiple genes and subject to genome–environment interactions. Early studies concentrated on analyzing the effects of single genes on behaviors, often generating views of simplified linear genetic pathways. The genome era has generated a profound paradigm shift enabling us to identify all the genes that contribute to expression of a behavioral phenotype, to investigate how they are organized as functional ensembles and to begin to identify polymorphisms that contribute to phenotypic variation and are targets for natural selection. Recent studies show that the genetic architecture of behavior is determined by dynamic and plastic modular networks of pleiotropic genes and that the behavioral phenotype manifests itself as an emergent property of such networks. Such networks are exquisitely sensitive to genetic background and sex effects. This review describes how Drosophila can serve as a model for uncovering fundamental principles of the genetic architecture of behavior. BioEssays 26:1299–1306, 2004. © 2004 Wiley Periodicals, Inc.
An extracellular driving force of cell‐shape changes
Authors: Schmidt Otto , Theopold Ulrich
Published: November 2004

The cellular capacity to internalise objects, involving attachment, engulfment and uptake, exists in virtually all organisms. Many uptake reactions are associated with cell signalling. However, the mechanical forces that form endocytotic vesicles are not known. We propose a ‘leverage‐mediated’ uptake mechanism involving lateral cross‐linking processes on the cell surface that can generate the configurational energy to create an inverse curvature of the membrane. BioEssays 26:1344–1350, 2004. © 2004 Wiley Periodicals, Inc.
Hold the germ cells, I'm on duty
Authors: Extavour Cassandra G.
Published: November 2004

Germ cell segregation and gamete production are developmental problems that all sexually reproducing species must solve in order to survive. Many people are familiar with the complex social structures of some insect species, where specialised castes of adult insects perform specific tasks, one of which is usually to guard the sexually reproductive queen. The parasitic wasp Copidosoma floridanum adds another level of complexity to the caste system: a fertilised egg produces both sterile, short‐lived “soldier” larvae and “reproductive” larvae that complete metamorphosis to produce sexually reproductive adults. How two morphologically and functionally distinct larval castes are produced by genetically identical groups of cells developing under the same environmental conditions is a baffling problem. A recent paper suggests that differential germ cell segregation during embryogenesis may be an event both necessary and sufficient for caste determination.1 BioEssays 26:1263–1267, 2004. © 2004 Wiley Periodicals, Inc.
The Versatile, Efficient, and Stereoselective Self‐Assembly of Transition‐Metal Helicates by Using Hydrogen‐Bonds
Authors: Telfer Shane G. , Kuroda Reiko
Published: November 2004

A diverse range of dinuclear double‐stranded helicates in which the ligand strand is built up by using hydrogen‐bonding has been synthesized. The helicates, formulated as [Co2(L)2(L‐H)2X2], readily self‐assemble from a mixture of a suitable pyridine–alcohol compound (L; for example, 6‐methylpyridine‐2‐methanol, 1), and a CoX2 salt in the presence of base. Nine such helicates have been characterized by X‐ray crystallography. For helicates derived from the same pyridine–alcohol precursor, a remarkable regularity was found for both the molecular structure and the crystal packing arrangements, regardless of the nature of the ancillary ligand (X). A notable exception was observed in the solid‐state structure of [Co2(1)2(1‐H)2(NCS)2] for which intermolecular nonbonded contacts between the sulfur atoms (S⋅⋅⋅S=3.21 Å) lead to the formation of 1D chains. Helicates derived from (R)‐6‐methylpyridine‐2‐methanol (2) are soluble in solvents such as CH3CN and CH2Cl2, and their self‐assembly could be monitored in solution by 1H NMR, UV/Vis, and CD titrations. No intermediate complexes were observed to form in a significant concentration at any point throughout these titrations. The global thermodynamic stability constant of [Co2(2)2(2‐H)2(NO3)2] was calculated from spectrophotometric data to be logβ=8.9(8). The stereoisomerism of these helicates was studied in some detail and the self‐assembly process was found to be highly stereoselective. The chirality of the ligand precursors can control the absolute configuration of the metal centers and thus the overall helicity of the dinuclear assemblies. Furthermore, the enantiomers of rac‐6‐methylpyridine‐2‐methanol (3) undergo a self‐recognition process to form exclusively homochiral helicates in which the four pyridine–alcohol units possess the same chirality.
New Chiral Auxiliaries for Dynamic Kinetic Resolution: From Theory to Experiment
Authors: Santos A. Gil , Pereira Jorge , Afonso Carlos A. M. , Frenking Gernot
Published: November 2004

New efficient chiral auxiliaries for dynamic kinetic resolution (DKR) of bromides into amines are proposed, based on a theoretical rationalisation of known literature results. One example was synthesized and tested, affording diastereoselectivities up to 100 %. Several results of DKR reactions are known, based on oxazolidinone or imidazolidinone units as chiral auxiliaries. Nevertheless, their behaviour was not fully understood until a recent paper that we published. We now used our proposed mechanism to rationalize the behaviour of other similar chiral auxiliaries and to propose small structure changes in imidazolidinone rings which could largely improve their performance. We could show that the good performance of these molecules as chiral auxiliaries for DKR reactions where bromine is the leaving group and a primary or secondary amine is the nucleophile is due, in a first step, to the formation of a hydrogen bond between the amine and the ring carbonyl oxygen and, in a second step, to the strong electrostatic interaction between the leaving bromide and the carbonyl oxygen in the C‐3 substituent. Considering the behaviour of this substituent which rotates to minimize the electrostatic repulsion with the bromide when reaching the transition state, we proposed the introduction of a second substituent in the C‐4 position of the imidazolidinone ring, which prevents such rotation, thus increasing the energy difference between the transition states of the two distereoisomers. With such an auxiliary we were able to increase the best de known in literature (88 %), when benzylamine is used as nucleophile, to 99, or even 100 %, when iodide replaces the bromide in the substrate.
Explanation of the Anomalous Complexation of Silver(I) with Ammonia in Terms of the Poor Affinity of the Ion for Water
Authors: Antolovich Michael , Lindoy Leonard F. , Reimers Jeffrey R.
Published: November 2004

For Abstract see ChemInform Abstract in Full Text.
Interwoven Pair of Open Frameworks in the Thiosphosphate K6Yb3(PS4)5.
Authors: Aitken Jennifer A. , Kanatzidis Mercouri G.
Published: November 2004

For Abstract see ChemInform Abstract in Full Text.
A Practical Synthesis of Optically Active Aromatic Epoxides via Asymmetric Transfer Hydrogenation of α‐Chlorinated Ketones with Chiral Rhodium‐Diamine Catalyst.
Authors: Hamada Takayuki , Torii Takayoshi , Izawa Kunisuke , Ikariya Takao
Published: November 2004

For Abstract see ChemInform Abstract in Full Text.
3,3′‐Functionalized Octahydro‐BINOL: A Facile Synthesis and Its High Enantioselectivity in the Alkyne Addition to Aldehydes.
Authors: Liu Lan , Pu Lin
Published: November 2004

For Abstract see ChemInform Abstract in Full Text.
Highly Efficient Synthesis of β‐Amino Acid Derivatives via Asymmetric Hydrogenation of Unprotected Enamines.
Authors: Rivera Nelo R. , et al. et al.
Published: November 2004

For Abstract see ChemInform Abstract in Full Text.
Studies on the Regio‐ and Stereoselectivity of Halohydroxylation of 1,2‐Allenyl Sulfides or Selenides.
Authors: Ma Shengming , Hao Xueshi , Meng Xiaofeng , Huang Xian
Published: November 2004

For Abstract see ChemInform Abstract in Full Text.
Synthesis of 4‐Substituted Bisnaphthalimides.
Authors: Kupriyan D. G. , Anikin V. F. , Merz A. , Pantsenker L. D.
Published: November 2004

For Abstract see ChemInform Abstract in Full Text.
Synthesis of 5‐Methylindole‐4,7‐quinone Through a New Construction of the Functionalized Indole Ring Based on the Allene‐Mediated Electrocyclic Reaction Involving the Pyrrole[b]‐Bond.
Authors: Hirayama Maho , Choshi Tominari , Kumemura Teppei , Tohyama Shigeo , Nobuhiro Junko , Hibino Satoshi
Published: November 2004

For Abstract see ChemInform Abstract in Full Text.
New Synthetic Method for Indole‐2‐carboxylate and Its Application to the Total Synthesis of Duocarmycin SA.
Authors: Hiroya Kou , Matsumoto Shigemitsu , Sakamoto Takao
Published: November 2004

For Abstract see ChemInform Abstract in Full Text.
Unusual Oxidation Behavior of a Propargylic Alcohol.
Authors: Porter Michael J. , White Nicola J. , Howells Garnet E. , Laffan David D. P.
Published: November 2004

For Abstract see ChemInform Abstract in Full Text.
Design and Synthesis of Cyclic Urea Compounds: A Pharmacological Study for Retinoidal Activity.
Authors: Kurihara Masaaki , Rouf Abu Shara Shamsur , Kansui Hisao , Kagechika Hiroyuki , Okuda Haruhiro , Miyata Naoki
Published: November 2004

For Abstract see ChemInform Abstract in Full Text.
Novel Synthesis of Substituted Benzimidazoles by Reduction of Esters of 4‐Alkylamino‐3,5‐dinitrobenzoic Acids by Tin Chloride.
Authors: Vlaskina A. V. , Perevalov V. P.
Published: November 2004

For Abstract see ChemInform Abstract in Full Text.
Synthesis of Novel 3,5‐Disubstituted‐4‐isothiazolecarbonitriles.
Authors: Mishra Manisha , Chowdhury S. K. Dutta , Mahalanabis Kumar K.
Published: November 2004

For Abstract see ChemInform Abstract in Full Text.
Synthesis and Insecticidal Activity of Some 1,3,4‐Oxadiazole Derivatives Containing Phenoxyfluorophenyl Group.
Authors: Mohan T. P. , Vishalakshi B. , Bhat K. S. , Rao K. S. , Kendappa G. N.
Published: November 2004

For Abstract see ChemInform Abstract in Full Text.
Reversal of Diastereoselection in the Addition of Grignard Reagents to Chiral 2‐Pyridyl tert‐Butyl (Ellman) Sulfinimines.
Authors: Kuduk Scott D. , DiPardo Robert M. , Chang Ronald K. , Ng Christina , Bock Mark G.
Published: November 2004

For Abstract see ChemInform Abstract in Full Text.
Indium Mediated Allylation of Quinoline and Isoquinoline Activated by Phenyl Chloroformate.
Authors: Lee Seung Hwan , Park Young Sang , Nam Mi Hae , Yoon Cheol Min
Published: November 2004

For Abstract see ChemInform Abstract in Full Text.
Synthesis and Antileishmanial Activity of (1,3‐Benzothiazol‐2‐yl) Amino‐9‐(10H)‐acridinone Derivatives.
Authors: Delmas Florence , Avellaneda Antonio , Di Giorgio Carole , Robin Maxime , De Clercq Erik , Timon‐David Pierre , Galy Jean‐Pierre
Published: November 2004

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Synthesis of 5H‐Pyrazolo[4,3‐c]quinolines.
Authors: Silin Olexiy V. , Savchenko Timur I. , Kovalenko Sergiy M. , Nikitchenko Viktor M. , Ivachtchenko Alexandre V.
Published: November 2004

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An Inexpensive Protocol for Biginelli Reaction.
Authors: Manjula A. , Rao B. Vittal , Neelakantan Parvathi
Published: November 2004

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Synthesis and QSAR Studies of Pyrimido[4,5‐d]pyrimidine‐2,5‐dione Derivatives as Potential Antimicrobial Agents.
Authors: Sharma Pratibha , Rane Nilesh , Gurram V. K.
Published: November 2004

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Novel Heterocyclic Analogues of the HIV‐1 Protease Inhibitor, Ritonavir.
Authors: Kaye Perry T. , Musa Musiliyu A. , Nchinda Aloysius T. , Nocanda Xolani W.
Published: November 2004

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Extending Pummerer Reaction Chemistry. Application to the Oxidative Cyclization of Tryptophan Derivatives.
Authors: Feldman Ken S. , Karatjas Andrew G.
Published: November 2004

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Low Molecular Weight Thrombin Inhibitors with Excellent Potency, Metabolic Stability, and Oral Bioavailability.
Authors: Morrissette Matthew M. , et al. et al.
Published: November 2004

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A Practical Method for the Stereoselective Generation of β‐2‐Deoxy Glycosyl Phosphates.
Authors: Oberthuer Markus , Leimkuhler Catherine , Kahne Daniel
Published: November 2004

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New Type of Trimeric and Pentameric Indole Alkaloids from Psychotria rostrata
Authors: Takayama Hiromitsu , Mori Ikue , Kitajima Mariko , Aimi Norio , Lajis Nordin H.
Published: November 2004

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A New Approach to the Synthesis of Cyclic Ethers via the Intermolecular Allylation of α‐Acetoxy Ethers and Ring‐Closing Metathesis.
Authors: Kadota Isao , Uyehara Hiroshi , Yamamoto Yoshinori
Published: November 2004

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Pb2+ Sensing Chemo‐Sensor: Thiacalix[4]crown‐Based Lumino‐ionophore.
Authors: Kim Sung Kuk , Lee Jae Kwang , Lim Jae Min , Kim Jong Wan , Kim Jong Seung
Published: November 2004

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Synthesis and Antibacterial Activity of 2‐(4‐Substituted phenyl)‐3(2H)‐isothiazolones.
Authors: Khalaj Ali , Adibpour Neda , Shahverdi Ahmad Reza , Daneshtalab Mohsen
Published: November 2004

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Anti‐HIV Activity of Some Synthetic Lignanolides and Intermediates.
Authors: Sancho Rocio , Medarde Manuel , Sanchez‐Palomino Sonsoles , Madrigal Blanca M. , Alcami Jose , Munoz Eduardo , San Feliciano Arturo
Published: November 2004

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Factors Governing Oxygen Reduction in Solid Oxide Fuel Cell Cathodes
Authors: Adler Stuart B.
Published: November 2004

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Organo‐Transition‐Metal Cluster Complexes
Authors: Humphrey Mark G. , Cifuentes Marie P.
Published: November 2004

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Phosphorus Ligands
Authors: Downing J. H. , Smith M. B.
Published: November 2004

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The Biginelli Dihydropyrimidinone Synthesis
Authors: Kappe C. Oliver , Stadler Alexander
Published: November 2004

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Six‐Membered Ring Systems: Diazines and Benzo Derivatives
Authors: Groziak Michael P.
Published: November 2004

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Microwave‐Supported Organic Synthesis. Applications. Part 25.
Authors: Keller Walter E.
Published: November 2004

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Asymmetric Synthesis of Biologically Active Compounds
Authors: Kagan Henri
Published: November 2004

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The Solid‐State Radiation Chemistry of Simple Amino Acids ( Revisited)
Authors: Sagstuen Einar , Sanderud Audun , Hole Eli O.
Published: November 2004

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5,7‐Diamino‐3,5,7,9‐tetradeoxy‐non‐2‐ulosonic Acids in Bacterial Glycopolymers: Chemistry and Biochemistry
Authors: Knirel Yuriy A. , Shashkov Alexander S. , Tsvetkov Yury E. , Jansson Per‐Erik , Zaehringer Ulrich
Published: November 2004

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Nonaqueous Liquid Electrolytes for Lithium‐Based Rechargeable Batteries
Authors: Xu Kang
Published: November 2004

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State of Understanding of Nafion
Authors: Mauritz Kenneth A. , Moore Robert B.
Published: November 2004

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Transport in Proton Conductors for Fuel‐Cell Applications: Simulations, Elementary Reactions, and Phenomenology
Authors: Kreuer Klaus‐Dieter , Paddison Stephen J. , Spohr Eckhard , Schuster Michael
Published: November 2004

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3D‐Coordination Cluster Polymers [Ln(H2O)3Re6Te8(CN)6]·nH2O (Ln = La3+, Nd3+): Direct Structural Analogy with the Mononuclear LnM(CN)6·nH2O Family
Authors: Artemkina Sofia B. , Naumov Nikolai G. , Virovets Alexander V. , Fedorov Vladimir E.
Published: November 2004

Using the hydrothermal method two novel 3D‐coordination complexes [Ln(H2O)3Re6Te8(CN)6]·nH2O (Ln = La3+, Nd3+) have been synthesised and structurally characterised. For compound [La(H2O)3Re6Te8(CN)6]·4H2O (1) the unit cell parameters are: Space group P63/m, a = 9.3060(13), c = 20.528(4) Å, V = 1539.6(4) Å3, Rf = 0.0597. For compound [Nd(H2O)3Re6Te8(CN)6]·H2O (2) the unit cell parameters are: Space group P63/m, a = 9.3030(10), c = 20.222(4) Å, V = 1515.7(4) Å3, Rf = 0.0226. The structures of the cluster compounds are topologically analogous to the mononuclear polymeric complex LaCr(CN)6·5H2O. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005)
The Reaction of (Bipyridyl)palladium(II) Complexes with Thiourea − Influence of DNA and Other Polyanions on the Rate of Reaction
Authors: Cusumano Matteo , Di Pietro Maria Letizia , Giannetto Antonino , Vainiglia Pasquale Antonio
Published: November 2004

[Pd(bipy)(py)2](PF6)2 reacts stepwise with excess thiourea to give [Pd(tu)4](PF6)2. The kinetics of the second step, which refers to the replacement of bipyridyl in [Pd(bipy)(tu)2](PF6)2, have been studied in water and in the presence of calf thymus DNA, sodium polyriboadenylate, sodium polyvinylsulfonate or sodium polymetaphosphate at 25 °C and pH = 7 and a fixed sodium chloride concentration. The reaction follows a first order course and a plot of kobs against [thiourea]2 affords a straight line with a small intercept. DNA inhibits the process without altering the rate law. The kobs values decrease systematically on increasing the DNA concentration eventually tending to a limiting value. The values are larger at higher ionic strengths and the other polyanions show similar behaviour. The influence of DNA on the kinetics can be related to steric inhibition caused by noncovalent binding with the complex. Upon interaction with DNA, [Pd(bipy)(tu)2]2+ gives rise to immediate spectroscopic changes in the UV/Vis region as well as induced circular dichroism suggesting that the complex, like similar platinum(II) and palladium(II) species of bipyridyl, intercalates with the double helix. Such a type of interaction hampers the attack of the nucleophile at the metal centre inhibiting the reaction. The decrease in the rate of ligand substitution upon decreasing salt concentration but at a given DNA concentration is due to the influence of ionic strength on the complex−DNA interaction. The reactivity inhibition by single‐stranded poly(A), polyvinylsulfonate or polymetaphosphate can be accounted for in terms of self‐aggregation of the complex induced by the polyanion. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005)
Synthesis, Characterization, and Hydrolysis Products of (η2‐tBu2pz)AlH(μ:η1,η1‐tBu2pz)2AlH2 − Structural Characterization of a Complex Containing η1‐, η2‐, and μ:η1,η1‐Pyrazolato Ligands and a Complex Containing a Terminal Hydroxo Ligand
Authors: Yu Zhengkun , Knox John E. , Korolev Andrey V. , Heeg Mary Jane , Schlegel H. Bernhard , Winter Charles H.
Published: November 2004

Treatment of alane−ethyldimethylamine with 3,5‐di‐tert‐butylpyrazole (tBu2pzH) in a 2:3 molar ratio afforded [(η2‐tBu2pz)AlH(μ:η1,η1‐tBu2pz)2AlH2] in 57% yield. Hydrolysis of [(η2‐tBu2pz)AlH(μ:η1,η1‐tBu2pz)2AlH2] afforded variable mixtures of Al(tBu2pz)3, [(η2‐tBu2pz)AlH(μ:η1,η1‐tBu2pz)2AlH(OH)], and [(η2‐tBu2pz)AlH(μ:η1,η1‐tBu2pz)2AlH(η1‐tBu2pz)]. The structures of all new complexes were assigned from spectral and analytical data. In addition, the X‐ray crystal structures of [(η2‐tBu2pz)AlH(μ:η1,η1‐tBu2pz)2AlH(OH)] and [(η2‐tBu2pz)AlH(μ:η1,η1‐tBu2pz)2AlH(η1‐tBu2pz)] were determined. [(η2‐tBu2pz)AlH(μ:η1,η1‐tBu2pz)2AlH(OH)] crystallizes as a dimeric molecule, and contains two bridging pyrazolato ligands, one η2‐pyrazolato ligand, as well as terminal hydrido and hydroxo ligands. The hydroxo and η2‐pyrazolato ligands possess a syn‐relationship within the dimer. The hydroxy group proton does not participate in dihydrogen bonding, and instead appears to be intramolecularly hydrogen‐bonded to the π‐cloud of the η2‐pyrazolato ligand. The overall structure of [(η2‐tBu2pz)AlH(μ:η1,η1‐tBu2pz)2AlH(η1‐tBu2pz)] is very similar to that of [(η2‐tBu2pz)AlH(μ:η1,η1‐tBu2pz)2AlH(OH)], except that the η1‐ and η2‐pyrazolato ligands have an anti‐disposition within the dimer. Molecular orbital calculations were carried out on [(η2‐tBu2pz)AlH(μ:η1,η1‐tBu2pz)2AlH(OH)] to understand the hydrogen bonding and the η2‐pyrazolato ligand coordination. The calculations predict that there is a 1.4 kcal/mol energy difference between η1‐ and η2‐pyrazolato ligand coordination, which implies that the observed η2‐pyrazolato ligand occurs due to accommodation of the bulky tert‐butyl groups. The intramolecular hydrogen bond between the hydroxo ligand proton and the π‐cloud of the η2‐pyrazolato ligand is estimated to have a bond strength of 3.7 kcal/mol. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005)
Effectiveness of dimethylpolysiloxane during deep frying
Authors: Márquez‐Ruiz Gloria , Velasco Joaquín , Dobarganes M. Carmen
Published: November 2004

In the last decades, silicones and particularly dimethylpolysiloxane (DMPS) added to oils and fats at very low concentrations (1–5 mg/kg) have been widely applied as inhibitors of thermoxidative reactions in deep frying. In this review, information available on the mechanisms of DMPS action during the frying process is summarised. Studies on samples submitted to high temperature in the absence of foods, as well as those on continuous and discontinuous frying, are commented upon. It is concluded that the different effects reported can be attributed to the high number of variables interacting during frying. The maximum effectiveness of DMPS was obtained in discontinuous frying operations when the oil surface becomes unprotected against oxidation due to the absence of the food. On the contrary, in industrial continuous frying, the addition of DMPS was found to be ineffective due to the protection of the surface by steam originating from the food.
Attenuation of telomerase activity by hammerhead ribozyme targeting human telomerase RNA induces growth retardation and apoptosis in human breast tumor cells
Authors: Yeo Marie , Rha Sung Young , Jeung Hei Cheul , Hu Shen Xiong , Yang Sang Hwa , Kim Yang Seok , An Sung Whan , Chung Hyun Cheol
Published: November 2004

Ribozyme possesses specific endoribonuclease activity and catalyzes the hydrolysis of specific phosphodiester bonds, which results in the cleavage of target RNA sequences. Here, we evaluated the ability of hammerhead ribozymes targeting human telomerase RNA (hTR) to inhibit the catalytic activity of telomerase and the proliferation of cancer cells. Hammerhead ribozymes were designed against 7 NUX sequences located in open loops of the hTR secondary structure. We verified the ribozyme specificity by in vitro cleavage assay by using a synthetic RNA substrate. Subsequently, we introduced ribozyme expression vector into human breast tumor MCF‐7 cells and assessed the biologic effects of ribozyme. Hammerhead ribozyme R1 targeting the template region of hTR efficiently cleaved hTR in vitro, and stable transfectants of this ribozyme induced the degradation of target hTR RNA and attenuated telomerase activity in MCF‐7 cells. Moreover, the ribozyme R1 transfectant displayed a significant telomere shortening and a lower proliferation rate than parental cells. Clones with reduced proliferation capacity showed enlarged senescence‐like shapes or highly differentiated dendritic morphologies of apoptosis. In conclusion, the inhibition of telomerase activity by hammerhead ribozyme targeting the template region of the hTR presents a promising strategy for inhibiting the growth of human breast cancer cells. © 2004 Wiley‐Liss, Inc.