bluuebunny/crossref_metadata_2025 huggingface dataset:
Blockade of PSGL-1 attenuates CD14+ monocytic cell recruitment in intestinal mucosa and ameliorates ileitis in SAMP1/Yit mice
Authors: Inoue Takuya , Tsuzuki Yoshikazu , Matsuzaki Koji , Matsunaga Hisayuki , Miyazaki Junichi , Hokari Ryota , Okada Yoshikiyo , Kawaguchi Atsushi , Nagao Shigeaki , Itoh Kazuro , Matsumoto Satoshi , Miura Soichiro
Published: November 2004

The pathogenesis of Crohn's disease (CD) is not known. However, monocytes and macrophages are thought to play important roles in the development of mucosal inflammation. Therefore, in this study, we examined the role of monocyte-endothelial cell interactions in senescence-accelerated mouse P1 (SAMP1)/Yit mice, a murine model of spontaneous ileitis. Fluorescence-labeled CD14+ monocytic cells isolated from the spleen and mesenteric lymph nodes of AKR/J (control) mice were injected into the tail veins of recipient (AKR/J and SAMP1/Yit) mice, and migration in the postcapillary venules (PCV) of Peyer's patches, submucosal venules, and villus microvessels of the terminal ileum was monitored by using an intravital microscope. Rolling and adhesion of CD14+ monocytic cells in the PCV of Peyer's patches and microvessels of the terminal ileum were increased in SAMP1/Yit mice. An imunohistochemical study showed increased expression of P-selectin glycoprotein-1 (PSGL-1), P-selectin, and vascular cell adhesion molecule-1 in the terminal ileum of SAMP1/Yit mice. Antibodies against these three adhesion molecules significantly inhibited adhesion of CD14+ monocytic cells to the PCV of Peyer's patches and microvessels of the terminal ileum, treatment with an anti-PSGL-1 monoclonal antibody (mAb) showing the strongest suppressive effect. Anti-PSGL-1 mAb also attenuated T cell adhesion in microvessels of intestinal mucosa. In addition, periodical administration of an anti-PSGL-1 mAb for 7 weeks significantly ameliorated ileitis of SAMP1/Yit mice. The results suggest that PSGL-1-P-selectin interaction plays an important role in monocyte-endothelial cell interactions and the development of ileitis in a murine model of CD and that the blockade of this adhesion molecule may be a novel strategy for treating CD.
Impact of LL-37 on anti-infective immunity
Authors: Bowdish Dawn M E , Davidson Donald J , Lau Y Elaine , Lee Ken , Scott Monisha G , Hancock Robert E W
Published: November 2004

Host defense peptides (often called cationic antimicrobial peptides) have pleiotropic immunomodulatory functions. The human host defense peptide LL-37 is up-regulated at sites of infection and has little or no antimicrobial activity in tissue-culture media but under the same conditions, demonstrates immunomodulatory effects on epithelial cells, monocytes, and dendritic cells (DC). These effects include the induction of chemokine production in a mitogen-activated protein kinase-dependent manner in epithelial cell lines and monocytes and profound alterations of DC differentiation, resulting in the capacity to enhance a T helper cell type 1 response. Although the exact mechanisms of interaction between LL-37 and these cell types have not been elucidated, there is evidence for specific (i.e., receptor-mediated) and nonspecific interactions. The relative significance of the direct antimicrobial activities and immunomodulatory properties of LL-37 and other cationic host defense peptides in host defense remains unresolved. To demonstrate that antimicrobial activity was not necessarily required for protection in vivo, model peptides were synthesized and tested for antimicrobial and immunomodulatory activities. A peptide with no antimicrobial activity was found to be protective in animal models of Staphylococcus aureus and Salmonella infection, implying that a host defense peptide can protect by exerting immunomodulatory properties.
Family history of primary movement disorders as a predictor for neuroleptic-induced extrapyramidal symptoms
Authors: Lencer Rebekka , Eismann Gunnar , Kasten Meike , Kabakci Kemal , Geithe Verena , Grimm Jenny , Klein Christine
Published: November 2004

Background

A genetic susceptibility to extrapyramidal symptoms caused by treatment with neuroleptic medication has been suggested.

Aims

To identify predictor variables for neuroleptic-induced extrapyramidal symptoms, particularly considering family history of primary movement disorders.

Method

We investigated 100 in-patients receiving a stable neuroleptic medication with regard to occurrence of extrapyramidal symptoms, drug history and detailed family history of primary movement disorders.

Results

Step-wise logistic regression analysis revealed that a positive family history was a significant predictor for lifetime prevalence of extrapyramidal symptoms, including reported and currently observed symptoms. The duration of exposure to neuroleptic medication and age were further predictors.

Conclusions

Our findings underline the notion of genetic susceptibility for secondary extrapyramidal symptoms and suggest possible shared genetic factors in primary and secondary movement disorders as well as psychotic disorders.
Efficacy of olanzapine combined with valproate or lithium in the treatment of dysphoric mania
Authors: Baker Robert W. , Brown Eileen , Akiskal Hagop S. , Calabrese Joseph R. , Ketter Terence A. , Schuh Leslie M. , Trzepacz Paula T. , Watkin John G. , Tohen Mauricio
Published: November 2004

Background

Few controlled studies examine the treatment of depressive features in mania.

Aims

To evaluate the efficacy of olanzapine, in combination with lithium or valproate, for treating depressive symptoms associated with mania.

Method

Secondary analysis of a 6-week, double-blind, randomised study of olanzapine (5–20 mg/day) or placebo combined with ongoing valproate or lithium open treatment for 344 patients in mixed or manic episodes. This analysis focused on a dysphoric subgroup with baseline Hamilton Rating Scale for Depression (HRSD) total scores of 20 or over contrasted with non-dysphoric patients.

Results

In the dysphoric subgroup (n=85) mean HRSD total score improvement was significantly greater in olanzapine co-therapy patients than in those receiving placebo plus lithium or valproate (P<0.001). Substantial contributors to this superiority included the HRSD Maier sub-scale (P=0.013) and the suicide item (P=0.001). Total Young Mania Rating Scale improvement was also superior with olanzapine co-therapy.

Conclusions

In patients with acute dysphoric mania, addition of olanzapine to ongoing lithium or valproate monotherapy significantly improved depressive symptom, mania and suicidality ratings.
What if Santa died? An invited response
Authors: Salter Mark
Published: November 2004

From late October each year, bleary-eyed postal workers all over the UK sit in shifts, sifting through some 120 000 children's letters addressed to a rubicund, septuagenarian, airborne logistics expert living in the frozen Arctic. In accordance with guidelines, every letter is screened for signs of neglect, abuse or some other singularity. Every year, several escape the shredder. One year, a thoughtful 10-year-old wrote.
Diagnostic Accuracy of the Palliative Prognostic Score in Hospitalized Patients With Advanced Cancer
Authors: Glare Paul A. , Eychmueller Steffen , McMahon Patrick
Published: November 2004

Purpose

To evaluate the predictive accuracy of the Palliative Prognostic (PaP) score in patients with advanced cancer under the care of an oncologist.

Patients and Methods

The PaP score was calculated in 100 consecutive patients with advanced cancer hospitalized under the care of a medical or radiation oncologist at a university teaching hospital in Australia. The attending oncologist predicted the survival duration for the purpose of the scoring. The positive predictive value of the PaP score was evaluated. Survival analysis was performed to compare the survival of the three prognostic groups.

Results

Assessable survival data were available for 98 patients. The overall median survival was 12 weeks (interquartile range, 7 to 25 weeks). The PaP score divided the heterogeneous patient sample into three isoprognostic groups related to the chance of surviving 1 month, with 64 patients in group A (> 70% chance), 32 patients in group B (30% to 70% chance), and four patients in group C (< 30% chance). The estimated median survival of the three groups was 17 weeks (95% CI, 12 to 26 weeks), 7 weeks (95% CI, 4 to 12 weeks), and less than 1 week (95% CI, < 1 to 3 weeks), respectively. These survival differences were highly significant (log-rank test of trend, χ12 = 25.65; P < .0001). The 1-month survival of the groups was 97%, 59%, and 25%, respectively.

Conclusion

When oncologists' survival estimates are used, the PaP score is able to identify accurately three isoprognostic patient groups, irrespective of the cancer type. The PaP score may help reduce the uncertainty of formulating a prognosis in patients with advanced cancer.
Change-point models and conditionally pure birth processes: an inequality on the stochastic intensity
Authors: De Santis Emilio , Spizzichino Fabio
Published: November 2004

We analyse several aspects of a class of simple counting processes that can emerge in some fields of applications where a change point occurs. In particular, under simple conditions we prove a significant inequality for the stochastic intensity.
Occupation time processes of super-Brownian motion with cut-off branching
Authors: Dong Zhao , Feng Shui
Published: November 2004

In this article we investigate a class of superprocess with cut-off branching, studying the long-time behavior of the occupation time process. Persistence of the process holds in all dimensions. Central-limit-type theorems are obtained, and the scales are dimension dependent. The Gaussian limit holds only when d ≤ 4. In dimension one, a full large deviation principle is established and the rate function is identified explicitly. Our result shows that the super-Brownian motion with cut-off branching in dimension one has many features that are similar to super-Brownian motion in dimension three.
Stopping the maximum of a correlated random walk, with cost for observation
Authors: Allaart Pieter
Published: November 2004

Let (Sn)n≥0 be a correlated random walk on the integers, let M0 ≥ S0 be an arbitrary integer, and let Mn = max{M0, S1,…, Sn}. An optimal stopping rule is derived for the sequence Mn - nc, where c > 0 is a fixed cost. The optimal rule is shown to be of threshold type: stop at the first time that Mn - Sn ≥ Δ, where Δ is a certain nonnegative integer. An explicit expression for this optimal threshold is given.
Random walks on a complete graph: a model for infection
Authors: Datta Nilanjana , Dorlas Tony C.
Published: November 2004

We introduce a new model for the infection of one or more subjects by a single agent, and calculate the probability of infection after a fixed length of time. We model the agent and subjects as random walkers on a complete graph of N sites, jumping with equal rates from site to site. When one of the walkers is at the same site as the agent for a length of time τ, we assume that the infection probability is given by an exponential law with parameter γ, i.e. q(τ) = 1 - e-γτ. We introduce the boundary condition that all walkers return to their initial site (‘home’) at the end of a fixed period T. We also assume that the incubation period is longer than T, so that there is no immediate propagation of the infection. In this model, we find that for short periods T, i.e. such that γT ≪ 1 and T ≪ 1, the infection probability is remarkably small and behaves like T3. On the other hand, for large T, the probability tends to 1 (as might be expected) exponentially. However, the dominant exponential rate is given approximately by 2γ/[(2+γ)N] and is therefore small for large N.
A study of the Hartman–Watson distribution motivated by numerical problems related to the pricing of Asian options
Authors: Barrieu P. , Rouault A. , Yor M.
Published: November 2004

One approach to the computation of the price of an Asian option involves the Hartman–Watson distribution. However, numerical problems for its density occur for small values. This motivates the asymptotic study of its distribution function.
The first rendezvous time of Brownian motion and compound Poisson-type processes
Authors: Perry D. , Stadje W. , Zacks S.
Published: November 2004

The ‘rendezvous time’ of two stochastic processes is the first time at which they cross or hit each other. We consider such times for a Brownian motion with drift, starting at some positive level, and a compound Poisson process or a process with one random jump at some random time. We also ask whether a rendezvous takes place before the Brownian motion hits zero and, if so, at what time. These questions are answered in terms of Laplace transforms for the underlying distributions. The analogous problem for reflected Brownian motion is also studied.
Server advantage in tennis matches
Authors: MacPhee I. M. , Rougier Jonathan , Pollard G. H.
Published: November 2004

We show that the advantage that can accrue to the server in tennis does not necessarily imply that serving first changes the probability of winning the match. We demonstrate that the outcome of tie-breaks, sets and matches can be independent of who serves first. These are corollaries of a more general invariance result that we prove forn-point win-by-2 games. Our proofs are non-algebraic and self-contained.
Extinction times for a general birth, death and catastrophe process
Authors: Cairns Ben , Pollett P. K.
Published: November 2004

The birth, death and catastrophe process is an extension of the birth–death process that incorporates the possibility of reductions in population of arbitrary size. We will consider a general form of this model in which the transition rates are allowed to depend on the current population size in an arbitrary manner. The linear case, where the transition rates are proportional to current population size, has been studied extensively. In particular, extinction probabilities, the expected time to extinction, and the distribution of the population size conditional on nonextinction (the quasi-stationary distribution) have all been evaluated explicitly. However, whilst these characteristics are of interest in the modelling and management of populations, processes with linear rate coefficients represent only a very limited class of models. We address this limitation by allowing for a wider range of catastrophic events. Despite this generalisation, explicit expressions can still be found for the expected extinction times.
A Brownian motion with two reflecting barriers and Markov-modulated speed
Authors: Kella Offer , Stadje Wolfgang
Published: November 2004

We consider a Brownian motion with time-reversible Markov-modulated speed and two reflecting barriers. A methodology depending on a certain multidimensional martingale together with some linear algebra is applied in order to explicitly compute the stationary distribution of the joint process of the content level and the state of the underlying Markov chain. It is shown that the stationary distribution is such that the two quantities are independent. The long-run average push at the two barriers at each of the states is also computed.
Methylenetetrahydrofolate reductase gene A222V polymorphism and risk of ischemic stroke
Authors: Baum Larry , Wong Ka Sing , Ng Ho Keung , Tomlinson Brian , Rainer Timothy Hudson , Chan Daniel Kam Yin , Thomas G. Neil , Chen Xiangyan , Poon Peter , Cheung Wing Sze , Woo Kam Sang
Published: November 2004

The 5,10-methylenetetrahydrofolate reductase (
The assessment of bone metabolism in female elite endurance athletes by biochemical bone markers
Authors: Herrmann Markus , Herrmann Wolfgang
Published: November 2004

Purpose: Premature osteoporosis is a frequent problem in female athletes. Current concepts suggest that a disruption of the hypothalamic-pituitary axis leads to hypoestrogenism, which then causes amenorrhea and osteoporosis. However, the underlying mechanisms have been insufficiently investigated. Osteoprotegerin (OPG) and soluble TNF-α receptor antagonist ligand (sRANKL) regulate the balance of osteoblasts and osteoclasts. Their role in the pathogenesis of osteoporosis in female athletes has not been studied yet.

Methods: We measured OPG and sRANKL in relation to biochemical bone markers [osteocalcin (OC), bone alkaline phosphatase (BAP), serum β-crosslaps (CTx)] and female sex hormones [estradiol (E2) and luteinizing hormone (LH)] in fastening blood samples from 25 female elite endurance athletes and 25 matched controls.

Results: Athletes exhibited significantly higher levels of the bone resorption marker CTx than controls (0.61±0.26 vs. 0.44±0.15ng/ml). OPG and sRANKL were not changed. Subgroup analysis revealed that athletes using oral contraceptives [A-OCC(−)] had significantly higher levels of CTx (0.82±0.20 vs. 0.50±0.14ng/ml), BAP [37.3 (23.2–54.4) U/l vs. 25.2 (20.3–35.6) U/l] and OPG (3.4±0.8 vs. 2.7±0.8ng/ml) than controls who did not use oral contraceptives [C-OCC(−)]. While the difference for CTx exceeded the least significant change in this marker by approximately 30%, the differences for the bone formation markers OC and BAP were close to the least significant change. In athletes using oral contraceptives [A-OCC(+)] we found no differences compared to controls.

Conclusions: A-OCC(−) athletes have increased bone turnover with a particular stimulation of bone resorption. The increased bone resorption is not accompanied by a shift of the OPG/sRANKL relationship towards an osteoclastogenic constellation. Since increased bone resorption was not detectable in A-OCC(+) athletes, it can be suggested that OCC use might protect bone health in female athletes.
Production of gender-specific morning salivary cortisol reference intervals using internationally accepted procedures
Authors: Patel Rajan S. , Shaw Steve R. , MacIntyre Halena , McGarry Gerald W. , Michael Wallace A.
Published: November 2004

Background: Salivary cortisol concentrations correlate well with biologically active unbound free plasma cortisol concentrations. Despite its practical and analytical advantages, salivary cortisol measurement has been used mainly as a research tool rather than for the routine evaluation of adrenal function. This may be partly explained by the lack of robust reference data in the literature.

Methods: Using the recommended procedures for the production of reference intervals published by the International Federation of Clinical Chemistry, we aimed to produce morning salivary cortisol reference intervals for males and females. Salivary cortisol was measured in 496 specimens collected from 248 reference individuals (128 males, median age 41years, range 16–86; and 120 females, median age 44years, range 16–98) attending an otorhinolaryngology clinic. Reference individuals mailed saliva specimens sampled on two consecutive mornings to our laboratory, where cortisol concentrations were measured.

Results: Statistical analysis showed no significant correlation with age or body mass index. The following 95% gender-partitioned reference intervals were produced: males 10.9–40.3nmol/l; and females 9.3–40.3nmol/l.

Conclusion: Knowledge of these salivary cortisol reference intervals helps us monitor the adrenal function of outpatients using topical intranasal glucocorticoids for rhinosinusitis.
Concentrations of N-terminal pro-brain natriuretic peptide and troponin T in plasma of 75-year-old apparently healthy persons
Authors: Huber Klaus Roland , Mostafaie Nazanin , Bauer Kurt , Worofka Brigitte , Kittl Eva , Hofmann Jörg , Hejtman Milos , Redei Karoly , Jungwirth Susanne , Fischer Peter , Tragl Karl-Heinz
Published: November 2004

Clinical chemical reference values for older persons are sparse and mostly intermixed with those for younger persons. We had a unique opportunity to obtain blood samples from volunteers who were 75years old and living in two districts of Vienna, Austria. Consequently, we utilized stored plasma samples to obtain reference intervals for 120 apparently healthy 75-year-old participants for pro-brain natriuretic peptide (proBNP), as well as for troponin T. The N-terminal (NT)-proBNP protein assay is currently used as a diagnostic and prognostic aid in patients with heart failure and as a prognostic marker in acute coronary syndromes. Specifically, the concentration of NT-proBNP in serum or plasma aids in the prognosis of ventricular systolic dysfunction and helps to differentiate between cardiac and non-cardiac causes. The median NT-proBNP plasma value for men and women in our cohort was calculated as 98pg/ml, comparing favorably with reported values, in that a NT-proBNP concentration less than 100pg/ml excludes acutely decompensated heart failure. Our calculated 97.5 percentile was slightly higher (359 pg/ml) than the 97.5 percentile in a group of 50–65-year-old persons (198 and 222pg/ml for men and women, respectively) revealing the influence of age on this parameter. Because of its high tissue-specificity, cardiac troponin T is a cardiospecific, highly sensitive marker for myocardial damage. However, the troponin T concentrations in the plasma specimens from this cohort were all below the detection limit of 0.01ng/ml, preventing any further data handling.
The Food of Elders, the “Ration” of Women: Brewing, Gender, and Domestic Processes among the Samburu of Northern Kenya
Authors: Holtzman Jon
Published: November 2004

In recent years, many Samburu women have begun to brew beer and liquor for sale to elders—including their own husbands. Drawing on “cooperative conflict” approaches to domestic processes, the essay examines brewing in reference to the economic and cultural position of men and women within Samburu households and society at large. Focusing in particular on the issues posed to each gender by the differential control of key resources by the other—food by women and cash by men—the essay views brewing as a negotiated structure through which men and women address the particular gender‐based problems they encounter in daily life. [gender, family, brewing, Africa]
Female‐Selective Abortion in Asia: Patterns, Policies, and Debates
Authors: Miller Barbara D.
Published: November 2004

Since the early 1980s, the use of sex‐selective abortion increased in many Asian contexts. Estimates indicate that several million female fetuses were aborted in the last two decades of the twentieth century. This article takes a currently unusual approach for a cultural anthropologist in pursuing cross‐national comparisons of trends in sex‐selective abortion. The risks involved in such an approach are taken in the hope that it will yield insights not gained through localized analysis. After reviewing the available evidence on female‐selective abortion, I discuss features of Asian culture that support strong son preference. Next I review the related issues of increased technological availability for prenatal sex selection and national policies about sex selection. Last, I consider several positions on female‐selective abortion and how cultural anthropology may contribute to understanding the global context and consequences of prenatal gender discriminaiion. [Asia, son preference, sex‐selective abortion, globalization of reproduction]
Beliefs Matter: Cultural Beliefs and the Use of Cervical Cancer‐Screening Tests
Authors: Chavez Leo R. , McMullin Juliet M. , Mishra Shiraz I. , Hubbell F. Allan
Published: November 2004

In this article we examine the influence of cultural beliefs on behavior or, more specifically, beliefs about cervical cancer risk factors and the use of Pap exams. Individual Latinas' (Hispanic women) holding of beliefs similar to Latinas' generally (cultural consonance) did not significantly influence their use of Pap exams. Rather, structural factors such as medical insurance, age, marital status, education, and language acculturation explained Latinas' use of this medical service. However, when Latinas held beliefs similar to those of Anglo women, then they were significantly more likely to have had a Pap exam within the past two years. Latinas whose beliefs were closer to those of physicians were significantly less likely to have had the exam recently. Arriving at these findings involved both ethnographic interviews and survey research. That these beliefs proved to be significant influences on behavior suggests not only the important ways that beliefs matter but that ethnographic methods for examining those beliefs also matter. [Latinas and cervical cancer, Pap exams, culture and behavior, ethnography and survey research]
Cosmology, Anomaly, and Paradigm Shift in the Classroom
Authors: Zussman Mira
Published: November 2004

Most students step into our classrooms completely innocent of the notion of consciousness, consciousness studies, or the possibility of altering states of consciousness. Our task is to build our courses to meet these students needs at the undergraduate level, and to bring them slowly—and with care—into the realm of consciousness studies. Protection of human subjects surely extends to our students in the classroom and not just to natives of some distant or proverbial "bush.” There are, however, innumerable ways of doing just this—consciousness studies with attention to the wide range of student experience—in any of our courses and at any level of instruction, and with awareness that perhaps the most interesting study of consciousness takes place through the alchemy of teaching—right there in the midst of our own classroom.
Pace and Lead: The Grammar of Rapport
Authors: Bronson Matthew C.
Published: November 2004

Neurlolinguistic programming is a powerful technology for modelling aspects of human excellence so that others can achieve similar levels of effectiveness. This article describes how to teach a simple communication pattern called "pace and lead,” derived from studies of the hypnotic induction techniques of such master hypnotists as Milton Erickson. The "Pace and Lead" frame consists of several sensorily verifiable statements (pace) followed by a positive suggestion (lead). This pattern is the basis for virtually all communication which seeks to influence, manipulate or heal and as such, constitutes a very useful skill with a wide variety of applications.

This frame—simple in its outward form but profound in its potential extension to a variety of real world situations—deserves more general inclusion in the teaching of consciousness curriculum. Anthropologists with an interest in language and consciousness issues will appreciate the accessibility of the exercise and its ability to concretely embody abstract issues such as the role of language in the creation of personal and cultural "realities.”
The Challenge of Teaching Ethnopsychology
Authors: Michrina Barry
Published: November 2004

Ethnopsychology is the study of native theories and understandings of emotions, of illness and curing, and of self and personality. In teaching this subject I use techniques such as dramas and experiential exercises to aid in expanding students'cognitive, visceral, and political consciousness of the world's indigenous psychologies.
The Catalyzed NucleophilicAddition of Aldehydes to Electrophilic Double Bonds
Authors: Stetter Hermann , Kuhlmann Heinrich
Published: November 2004

The cyanide‐ion‐catalyzed dimerization of aromatic and heterocyclic aldehydes to α‐hydroxy ketones, also known as the benzoin condensation, is one of the oldest reactions in organic chemistry. A key intermediate in this reversible reaction is a nitrile‐stabilized carbanion. In 1973 it was shown that these carbanions add irreversibly to α,β‐unsaturated ketones, esters, and nitriles to give 1,4‐diketones, 4‐ketocarboxylic esters, and 4‐ketocarbonitriles, respectively. The reaction succeeds only in aprotic solvents, preferably dimethylformamide. Benzoins and aldehydes can be used interchangeably as starting materials since they are in rapid equilibrium. Cyanide ion catalysis fails with aliphatic aldehydes because they resinify under the strongly basic conditions. Vitamin B1(thiamine) has long been known to convert aliphatic aldehydes into acyloins in buffered aqueous solution. The catalytic effect of vitamin B1is due to the presence of a thiazolium cation. Thiazolium salts in general as well as other azolium salts also catalyze the formation of acyloins. The optimum conditions for thiazolium salt catalysis have been worked out. It was shown subsequently that thiazolium salts, in combination with bases, also catalyze the addition of aliphatic, aromatic, and heterocyclic aldehydes to α,β‐unsaturated carbonyl compounds. The 1,4‐diketones, 4‐ketocarboxylic esters, and 4‐ketocarbonitriles are usually formed in good to excellent yields. Cyanide ion and thiazolium salt catalysis thus complement each other.

This chapter covers the literature of the catalyzed nucleophilic addition of aldehydes to electrophilic double bonds up to 1988. The reaction has been reviewed previously.
Divinylcyclopropane‐CycloheptadieneRearrangement
Authors: Hudlicky Tomáš , Fan Rulin , Reed Josephine W. , Gadamasetti Kumar G.
Published: November 2004

The first documented report of a possible Cope rearrangement was probably that of Baeyer, who prepared eucarvone by hydrobromination of carvone in 1894. Although the transformation was briefly studied at that time, it was not until the 1950s that this and other Cope‐type rearrangements received detailed attention. The thermal isomerization ofcis‐divinylcyclopropane to cycloheptan‐1,4‐diene was reported by Vogel in 1960 during his studies of the Cope rearrangement of 1,5‐hexadienes annulated by a homologous series of carbocyclic rings. Scores of mechanistic studies followed this discovery upon the realization that the rearrangement could be related to the conceptually similar vinylcyclopropane–cyclopentene isomerization discovered a year earlier. It was also recognized that this rearrangement might be operating in the formation of cycloheptatriene from norcaradiene during photolysis of diazomethane in benzene. The topic received considerable attention in the 1960s, an era of mechanistic investigations of various concerted transformations. During the 1970s it enjoyed exploitation in many synthetic strategies, and the following decade the elements of this rearrangement were incorporated into tandem or multistep procedures in a preconceived manner. Many aspects of the various permutations of the Cope rearrangement have been previously reviewed.

The purpose of this review is to summarize the mechanistic, stereochemical, and practical results in this area in the context of the evolution of synthetic achievements during the last 40 years. Also described in this chapter are the transformations of several of the simple heteroatom permutations of this rearrangement in order to render appropriate comparisons of various systems. A discussion addresses those rearrangements of cyclopropanes, oxiranes, thiiranes, and aziridine rings substituted with vicinal vinyl groups. Excluded from this review are rearrangements of those divinylsubstituted three‐membered rings that contain more than a single heteroatom within the reacting manifold. Brief mention of these systems along with a guide to the literature is found in the last section of this chapter.

The literature is covered through December 1990. Many of the principal researchers in this field have been contacted and many unpublished transformations have been included in the tables.
TheBirch Reduction of Aromatic Compounds
Authors: Rabideau Peter W. , Marcinow Zbigniew
Published: November 2004

The reduction of aromatic compounds by alkali metals in liquid ammonia represents an important method for the preparation of partially unsaturated six‐membered rings. The reaction was discovered by Wooster and Godfrey, but the major development resulted from the efforts of A. J. Birch, and the reaction has since come to bear his name. Although a variety of metals can be used, the most common are sodium and lithium, and, to a lesser extent, potassium. Cosolvents such as ether or tetrahydrofuran (THF) are often used to improve solubility, and weak acids such as alcohols may be employed during the reaction as proton sources. The latter are necessary for the reduction of benzene and its unactivated derivatives. Improvement in experimental procedures by Wilds and Nelson, the application to polynuclear compounds by Hückel and later by Harvey, and the development of methods for the alkylation of the anions generated in this process (i.e., reductive alkylation) have made this reaction an important approach to the synthesis of a wide variety of organic compounds.
TheMitsunobu Reaction
Authors: Hughes David L.
Published: November 2004

Alkyl and aryl phosphites and phosphines react with compounds having weak heteroatom–heteroatom bonds, such as SS, OO, etc., and with azo compounds to form reactive phosphonium salts. These phosphonium salts in turn promote “redox” condensation reactions with compounds having active hydrogens. The condensation reaction of alcohols using the redox couple of a triaryl‐ or trialkylphosphine and a dialkyl azodicarboxylate has become known as the Mitsunobu reaction, based on his pioneering work in the late 1960s. The overall reaction is summarized, wherein the alcohol (R1OH) and acidic compound (H–Nu) are condensed to form product (R1–Nu), while triphenylphosphine is oxidized to triphenylphosphine oxide and the azodicarboxylate is reduced to the hydrazine. Although the typical redox combination is diethyl azodicarboxylate (DEAD) and triphenylphosphine, many other combinations have found selected use. The reaction is generally limited to primary and secondary alcohols, although tertiary alcohols react in a few intramolecular and intermolecular reactions. For secondary alcohols the reaction usually proceeds with clean inversion of stereochemistry. The acidic component of the reaction generally has an aqueous pKa < 15, with intramolecular reactions providing the exceptions. Examples of H–Nu include oxygen nucleophiles such as carboxylic acids and phenols; nitrogen nucleophiles such as imides, hydroxamates, and heterocycles; sulfur nucleophiles such as thiols and thioamides; and carbon nucleophiles such as β‐ketoesters.

Major reviews of the Mitsunobu reaction were published in 1981 by Mitsunobu and in 1983 by Castro. The former review concentrated on reactions using DEAD/triphenylphosphine, while the latter review focused on reactions in which halogens replaced the hydroxy group using reagents such as triphenylphosphine/carbon tetrachloride, triphenyl phosphite/iodomethane, and triphenylphosphine/N‐halosuccinimide. Reactions involving the DEAD/triphenylphosphine redox system are the principal subject of this chapter, with emphasis on the literature between 1981 and 1988.
Anion‐Assisted Sigmatropic Rearrangements
Authors: Wilson Stephen R.
Published: November 2004

The use of sigmatropic rearrangements for the synthesis of organic compounds has become one of the important synthetic tools available to the organic chemist, especially since the development of the detailed stereochemical understanding of these processes in terms of orbital symmetry. The flexibility and predictability of the Cope rearrangement make this type of process widely applicable. The interest and synthetic activity related to the Cope rearrangement can be seen in a previous review of the Claisen and Cope rearrangements. In that review, several variations of the rearrangement were discussed, including examples of the “oxy‐Cope” rearrangement. In 1975 examples of an oxy‐Cope rearrangement were reported wherein an enormous rate acceleration (10
15
) was observed on formation of the potassium salt of the oxy‐Cope substrate.

This chapter surveys extensions of this type of anionic substituent effect to other [3,3]‐, [5,5]‐, [1,3]‐, and [1,5]‐sigmatropic rearrangements as well as retro‐[2 + 2] and reverse Diels–Alder reactions. Specifically excluded are the ester enolate Claisen rearrangement which is mechanistically unrelated, the Wittig rearrangement, and the Haller–Bauer reaction. The chemical literature has been searched to the end of 1989. Emphasis is placed on reactions of synthetic utility, novelty, and generality.
The
N
azarov Cyclization
Authors: Habermas Karl L. , Denmark Scott E. , Jones Todd K.
Published: November 2004

The Nazarov cyclization is named after the eminent Russian chemist I. N. Nazarov (1900–1957). In the course of an extensive study on the formation of allyl vinyl ketones by the mercuric ion and acid‐catalyzed hydration of dienynes, Nazarov and his co‐workers discovered a secondary reaction to form 2‐cyclopentenones. Nazarov initially formulated a direct acid‐catalyzed closure of the allyl vinyl ketones and demonstrated the preparation of 2‐cyclopentenones from these precursors in dozens of cases. However in 1952, Braude and Coles suggested the intermediacy of carbocations and demonstrated that the formation of 2‐cyclopentenones actually proceeds via the α,α′‐divinyl ketones. This fact, together with further mechanistic clarification, has led to the current formulation of the Nazarov cyclization as the acid‐catalyzed closure of divinyl ketones to 2‐cyclopentenones.

This process was already documented in 1903. Treatment of dibenzylideneacetone with concentrated sulfuric acid and acetic anhydride followed by mild alkaline hydrolysis afforded a ketol, the correct structure of which was finally proposed in 1955. Other examples of acid‐catalyzed cyclizations of divinyl ketones exist in the early literature, as do reactions which must have proceeded via divinyl ketones.

A broader definition of the Nazarov cyclization includes a wide variety of precursors that under specific reaction conditions also produce 2‐cyclopentenones via divinyl ketones or their functional equivalents. A case in point is the formation of a cyclopentenone by treatment of either divinyl ketone or tetrahydropyrone with ethanolic hydrochloric acid. It is the structural variety of precursors that lends versatility to the Nazarov cyclization and which also serves as the organizational framework for this chapter.

To facilitate presentation, the reaction is divided into six categories defined by the structure of the precursor: (1) cyclization of divinyl and allyl vinyl ketones, (2) cyclization of silylated (stannylated) divinyl ketones, (3) in situ generation/cyclization of divinyl ketones or equivalents, (4) generation/cyclization of divinyl ketone equivalents by solvolysis, (5) alkyne‐based precursors of divinyl ketones, and (6) coupling reactions to form and cyclize divinyl ketones. The logic of this sequence follows from the order of decreasing structural similarity of the precursors to divinyl ketones. This is intended to be comprehensive in the coverage of cyclizations which produce 2‐cyclopentenones. The related electrocyclic closure of less oxidized pentadienylic cations is not covered. The reaction was most recently reviewed in 1991. Prior to that, the Nazarov cyclization had been reviewed in 1983 and also in the context of pentannulation.
Ketene Cycloadditions
Authors: Hyatt John A. , Raynolds Peter W.
Published: November 2004

The reaction of ketene with itself was described almost simultaneously in 1908 by Chick and Wilsmore in England, and by Staudinger and Klever in Germany; priority for the discovery was attributed to Wilsmore by the German group.

Ketene cycloaddition was an early example of a peculiar process, one that formed carbon–carbon bonds with ease, often without the need for solvent, catalyst, or high heat. Subsequent work by others was done in the shadow of Staudinger's exhaustive and rigorous study of all phases of ketene reactivity. Three factors led to a resurgence of interest in this reaction beginning in the 1960s. Haloketenes, which had previously eluded study, were found to have high reactivity, and the halogens could easily be removed after the reaction. The increasing sophistication of powerful analytical methods, particularly nuclear magnetic resonance spectroscopy, led to discovery of the interesting stereochemical aspects of this reaction. Finally, the new theory of orbital symmetry conservation provided a conceptual framework to rationalize these puzzling “no mechanism” reactions.

This chapter is a review of cycloaddition reactions of ketenes. Here, a cycloaddition is defined as a reaction of a ketene with an unsaturated organic compound to give a cyclic product by a mechanism that, in principle, involves the almost simultaneous formation of two bonds between two reactants. While there is no concern here as to whether bond formation is concerted or stepwise, no other chemical process can take place between the formation of the first and second bond. Definition here involves both structural and mechanistic factors, and it is difficult to avoid a certain amount of arbitrariness. Products, such as dehydroacetic acid, which seem to us to arise by concatenation of ketene molecules followed by cyclization are excluded. These reactions, are more properly considered to arise from a series of ionic reactions, and the prediction of the eventual product does not take advantage of the special mechanistic features commonly associated with true cycloadditions. Additions to imines to give β‐lactams are numerous and will be covered in a separate review. The literature has been searched to the end of 1988.

Many reviews devoted partially or exclusively to ketene cycloadditions have been published. Specific topics that have been reviewed include haloketenes, fluoroketenes, cyanoketenes, intramolecular cycloadditions, conjugated ketenes, and β‐lactam antibiotics. Ancillary topics pertinent to ketene cycloadditions that have been reviewed include cycloreversion reactions, ketene equivalents, which provide ketene functionality with olefin‐like reactivity especially in [4 + 2] reactions, application of frontier molecular orbital theory to cycloadditions, and a critical discussion of cycloadditions with polar intermediates. Applications of cyclobutanones in synthesis have also been reviewed.
Additions of Allyl, Allenyl, and Propargylstannanes to Aldehydes and Imines
Authors: Gung Benjamin W.
Published: November 2004

Natural products that contain stereocenters such as those having polyacetate and polypropionate structures are of considerable interest. Current technology for constructing these chiral molecules consists of strategies broadly defined as “acyclic stereocontrol.” The most efficient tools for this strategy include modern aldol reactions and the reaction of carbonyl compounds with allylmetal reagents. In order to achieve highly efficient syntheses of natural products rich with stereochemistry, highly stereoselective transformations are required. One solution is the use of allylstannane reagents. Their advantages include ease of handling, relative stability, and selective reactivity. The addition of allystannanes to aldehydes combines the process of CC bond formation with the stereoselective production of one or two new stereocenters. The configuration of these centers is predictable based on reaction conditions. Oxygen substitution also contributes to the versatility of these reagents. Recently developed chiral allenystannanes and the use of InCl3 as a transmetallation agent have greatly enhanced the practical utility of these reagents. This chapter is limited mainly to carbonyl and imine addition reactions, most of which create one or two new stereocenters.
Addition of Organochromium Reagents to Carbonyl Compounds
Authors: Takai Kazuhiko
Published: November 2004

Organochromium compounds can be prepared by two methods: (1) transmetallation from the corresponding organolithium, ‐magnesium, or –zinc compounds with chromium(III) halides, and (2) reduction of organic substrates, such as halides and unsaturated compounds with chromium(II) salts. The second method is usually the one ised because the first method suffers from low solubility of chromium(III) salts in ethereal solvents and from the difficulty of preparing organolithium compounds. Low‐valent chromium species are reducing agents. Reduction of various types of organic halides and compounds having unsaturated hetero‐hetero bonds with the chromium (II) species is discussed. Also described are the transmetallation to organochromium compounds from other organometallics, the nature of the carbon‐chromium bonds, and the X‐ray structure of chromium compounds. Reactions of organochromium reagents with carbonyl compounds and their scope and limitations are described. Included in this discussion are the geminal chromium reagents. Other reagents discussed are the chromium‐nickel compounds and alkylchromium and other organochromium reagents.
Ferroelectricity in Achiral Liquid‐Crystal Systems
Authors: Yablonskii S. V. , Soto‐Bustamante E. A. , Vergara‐Toloza R. O. , Haase W.
Published: November 2004

Ferroelectricity can be detected in systems consisting of liquid‐crystalline monomer–polymer mixtures possessing no chiral centers The ferroelectric behavior in mixtures of achiral liquid‐crystalline side‐chain polymers and achiral liquid‐crystalline monomers is reported for the first time. The mixtures manifested high pyroelectric activity, with values of spontaneous polarization close to the theoretical limit and a “figure of merit” comparable to the value of classic organic ferroelectric materials.
Preparation of Phthalocyanine Modified Electrodes. An Electrophoretic Approach
Authors: Milczarek Grzegorz , Ciszewski Aleksander
Published: November 2004

Ni(II) and Co(II) phthalocyanines were deposited from their solutions in pyridine. The resulting modified electrodes exhibited catalytic activity in alkaline media.
Effect of ion exchange of glazed dental glass ceramics on strength parameters
Authors: Fischer H. , Brehme M. , Telle R. , Marx R.
Published: November 2004

Ion exchange treatments can significantly increase the strength of dental glass ceramic core materials by induced compressive residual stresses. However, the core materials of dental restorations need to be veneered or at least to be stained and glazed for esthetic and functional reasons. The objective of this study was to determine the effect of different ion exchange treatments on the strength parameters of stained and glazed glass ceramics. Batches of specimens made of a leucite reinforced dental glass with and without staining and glazing layer, untreated, single ion exchanged (KNO3), and dual ion exchanged (1. KNO3/27, 2. 30 mol% NaNO3/70 mol% KNO3) were tested. The strength of the core material was increased from 117 to 213 MPa by single ion exchange. Staining and glazing increased the strength up to 165 MPa. Single ion exchange of the stained and glazed core caused only a slight additional strength increase up to 173 MPa. The dual ion exchanged stained and glazed core exhibit a strength of 195 MPa and decreased the large strength scatter because of a well‐designed residual stress profile. We conclude that dual ion exchange treatments could significantly increase the mechanical reliability of stained and glazed glass ceramic restorations. © 2004 Wiley Periodicals, Inc. J Biomed Mater Res 72A: 175–179, 2005
The agnoprotein of polyomaviruses: A multifunctional auxiliary protein
Authors: Khalili Kamel , White Martyn K. , Sawa Hirofumi , Nagashima Kazuo , Safak Mahmut
Published: November 2004

The late region of the three primate polyomaviruses (JCV, BKV, and SV40) encodes a small, highly basic protein known as agnoprotein. While much attention during the last two decades has focused on the transforming proteins encoded by the early region (small and large T‐antigens), it has become increasingly evident that agnoprotein has a critical role in the regulation of viral gene expression and replication, and in the modulation of certain important host cell functions including cell cycle progression and DNA repair. The importance of agnoprotein is underscored by its expression during lytic infection of glial cells by JCV that occurs in progressive multifocal leukoencephalopathy (PML), and also in some JCV‐associated human neural tumors particularly medulloblastoma. In this review, we will discuss the structure and function of agnoprotein in the viral life cycle during the course of lytic infection and the consequences of agnoprotein expression for the host cell. © 2004 Wiley‐Liss, Inc.