bluuebunny/crossref_metadata_2025 huggingface dataset:
Glycogen synthase kinase-3 inhibition disrupts nuclear factor-kappaB activity in pancreatic cancer, but fails to sensitize to gemcitabine chemotherapy
Authors: Mamaghani Shadi , Patel Satish , Hedley David W
Published: May 2009

Background

Aberrant activation NF-kappaB has been proposed as a mechanism of drug resistance in pancreatic cancer. Recently, inhibition of glycogen synthase kinase-3 has been shown to exert anti-tumor effects on pancreatic cancer cells by suppressing NF-kappaB. Consequently, we investigated whether inhibition of GSK-3 sensitizes pancreatic cancer cells to the chemotherapeutic agent gemcitabine.

Methods

GSK-3 inhibition was achieved using the pharmacological agent AR-A014418 or siRNA against GSK-3 alpha and beta isoforms. Cytotoxicity was measured using a Sulphorhodamine B assay and clonogenic survival following exposure of six different pancreatic cancer cell lines to a range of doses of either gemcitabine, AR-A014418 or both for 24, 48 and 72 h. We measured protein expression levels by immunoblotting. Basal and TNF-alpha induced activity of NF-kappaB was assessed using a luciferase reporter assay in the presence or absence of GSK-3 inhibition.

Results

GSK-3 inhibition reduced both basal and TNF-alpha induced NF-kappaB luciferase activity. Knockdown of GSK-3 beta reduced nuclear factor kappa B luciferase activity to a greater extent than GSK-3 alpha, and the greatest effect was seen with dual knockdown of both GSK-3 isoforms. GSK-3 inhibition also resulted in reduction of the NF-kappaB target proteins XIAP, Bcl-XL, and cyclin D1, associated with growth inhibition and decreased clonogenic survival. In all cell lines, treatment with either AR-A014418, or gemcitabine led to growth inhibition in a dose- and time-dependent manner. However, with the exception of PANC-1 where drug synergy occurred with some dose schedules, the inhibitory effect of combined drug treatment was additive, sub-additive, or even antagonistic.

Conclusion

GSK-3 inhibition has anticancer effects against pancreatic cancer cells with a range of genetic backgrounds associated with disruption of NF-kappaB, but does not significantly sensitize these cells to the standard chemotherapy agent gemcitabine. This lack of synergy might be context or cell line dependent, but could also be explained on the basis that although NF-kappaB is an important mediator of pancreatic cancer cell survival, it plays a minor role in gemcitabine resistance. Further work is needed to understand the mechanisms of this effect, including the potential for rational combination of GSK3 inhibitors with other targeted agents for the treatment of pancreatic cancer.
Pivotal Advance: Eosinophilia in the MES rat strain is caused by a loss–of–function mutation in the gene for cytochrome b(–245), alpha polypeptide (Cyba)
Authors: Mori Masayuki , Li Guixin , Hashimoto Maiko , Nishio Ayako , Tomozawa Hiroshi , Suzuki Nobuyoshi , Usami Shin–ichi , Higuchi Keiichi , Matsumoto Kiyoshi
Published: May 2009

NADPH oxidase plays a role in homeostatic regulation of innate immunity beyond conventional microbicidial functions.

MES is a rat strain that spontaneously develops severe blood eosinophilia as a hereditary trait. Herein, we report that eosinophilia in MES rats is caused by a loss–of–function mutation in the gene for cytochrome b(–245), α polypeptide (Cyba; also known as p22phox), which is an essential component of the superoxide–generating NADPH oxidase complex. The MES rat has a deletion of four nucleotides, including the 5′ splice donor GpT of intron 4 of the Cyba gene. As a consequence of the deletion, a 51–nucleotide sequence of intron 4 is incorporated into the Cyba transcripts. Leukocytes from the MES strain lack both CYBA protein and NADPH oxidase activity. Nevertheless, unlike patients with chronic granulomatous disease, who suffer from infections with pathogens due to similar genetic defects in NADPH oxidase, MES rats retain normal innate immune defense against Staphylococcus aureus infection. This is due to large quantities of peritoneal eosinophils in MES rats, which phagocytose and kill the bacteria. MES rat has a balance defect due to impaired formation of otoconia in the utricles and saccules. Eosinophilia of the MES rat was normalized by introduction of a normal Cyba transgene. The mechanisms by which impairment of NADPH oxidase leads to eosinophilia in the MES rat are elusive. However, our study highlights the essential role of NADPH oxidase in homeostatic regulation of innate immunity beyond conventional microbicidial functions.
Insulin-Like Growth Factor Type 1 Receptor and Insulin Receptor Isoform Expression and Signaling in Mammary Epithelial Cells
Authors: Rowzee Anne M. , Ludwig Dale L. , Wood Teresa L.
Published: May 2009

The insulin receptor (IR) isoforms and the IGF type 1 receptor (IGF-1R) share a high degree of structural homology but differ in ligand binding kinetics and functions. We developed a highly specific quantitative PCR assay to quantify and compare IR-A, IR-B, and IGF-1R expression within an RNA population. We determined receptor expression in primary murine mammary epithelial cells (MECs) during postnatal development. Both IR isoform mRNAs were 3- to 16-fold higher than IGF-1R expression at all developmental times. IR protein was also 3- to 10-fold higher than IGF-1R protein; however, significantly less IGF-1R was found in hybrid receptors at early (49%) vs. late (79%) pregnancy, indicating that the amount of hybrid receptor is developmentally regulated. Despite high IR expression, IGF ligands were more effective than insulin in stimulating the insulin receptor substrate-1/phosphatidylinositol 3-kinase/Akt pathway in acutely isolated MECs from virgin glands. Although approximately 40% of IR transcripts were the IGF-II-sensitive IR-A isoform, IGF-II failed to stimulate IR phosphorylation, and an IGF-1R-specific blocking antibody completely abrogated IGF-II-mediated Akt phosphorylation in the virgin MECs. Taken together, these data suggest that the IGF-1R is more active in signaling than the IR and is the predominant mediator of IGF actions in virgin MECs.
Activation of the Lutropin/Choriogonadotropin Receptor Inhibits Apoptosis of Immature Leydig Cells in Primary Culture
Authors: Tai Ping , Shiraishi Koji , Ascoli Mario
Published: May 2009

We used proliferating primary cultures of immature rat Leydig cells expressing the recombinant human LH/choriogonadotropin (CG) receptor (LHR) to test the hypothesis that activation of this receptor inhibits apoptosis. We also compared the effects of LH/CG with epidermal growth factor (EGF) and IGF-I because these have been previously shown to stimulate proliferation and/or inhibit apoptosis in Leydig cells. Human CG (hCG), EGF, and IGF-I stimulated the phosphorylation of ERK1/2 and Akt in primary cultures of immature rat Leydig cells. These three hormones also robustly stimulated thymidine incorporation and inhibited drug-induced apoptosis. Using selective inhibitors of ERK1/2 (UO126) or Akt phosphorylation (LY294002), we show that the ERK1/2 and Akt cascades are both involved in the hCG- and EGF-dependent proliferation of Leydig cells, but only the ERK1/2 cascade is involved in their antiapoptotic actions. The same strategy showed that the proliferative and antiapoptotic actions of IGF-I are mediated entirely by the Akt pathway. These results show that activation of the LHR inhibits apoptosis in Leydig cells and that it does so through stimulation of the ERK1/2 pathway.
Electroreception in the euryhaline stingray, Dasyatis sabina
Authors: McGowan D. W. , Kajiura S. M.
Published: May 2009

This study quantified the electrosensitivity of a euryhaline elasmobranch,the Atlantic stingray (Dasyatis sabina) across a range of salinities. Specimens from a permanent freshwater (FW) population in the St Johns River system, FL, USA, were compared with stingrays from the tidally dynamic Indian River Lagoon in east Florida, USA. Behavioral responses of stingrays to prey-simulating electric stimuli were quantified in FW (0 p.p.t., ρ=2026Ω cm), brackish (15 p.p.t., ρ=41 Ω cm) and full strength seawater (35 p.p.t., ρ=19 Ω cm). This study demonstrated that the electrosensitivity of D. sabina is significantly reduced in FW. In order to elicit a feeding response, stingrays tested in FW required an electric field 200–300× greater than stingrays tested in brackish and saltwater (median FW treatments=1.4 μV cm–1, median brackish–saltwater treatments=6 nV cm–1), and the maximum orientation distance was reduced by 35.2%, from 44.0 cm in the brackish and saltwater treatments to 28.5 cm in FW. The St Johns River stingrays did not demonstrate an enhanced electrosensitivity in FW, nor did they exhibit reduced sensitivity when introduced to higher salinities. Stingrays from both populations responded similarly to the prey-simulating stimulus when tested at similar salinities, regardless of their native environment. The reduction in electrosensitivity and detection range in FW is attributed to both an environmental factor (electrical resistivity of the water) and the physiological function of the ampullary canals. The plasticity of this sensory system to function across such a wide environmental range demonstrates its adaptive significance.
Biomechanics of byssal threads outside the Mytilidae: Atrina rigida and Ctenoides mitis
Authors: Pearce Trevor , LaBarbera Michael
Published: May 2009

The byssus is the set of proteinaceous threads widely used by bivalves to attach themselves to the substrate. Previous researchers have focused on a single byssate family, the Mytilidae. However, the properties of byssal threads from species outside this family are of interest – first,because evolutionary patterns are only detectable if species from a range of taxa are examined, and second, because recent biomimetic research efforts would benefit from a wider range of `mussel glue' exemplars. In the present study, we measured the mechanical properties of the byssal threads of two species outside the Mytilidae, the pen shell Atrina rigida Lightfoot and the flame `scallop' Ctenoides mitis Lamarck. The mechanical properties of their byssal threads were significantly different from those of mytilids. For instance, the byssal threads of both species were significantly weaker than mytilid threads. Atrina rigida threads were significantly less extensible than mytilid threads, while C. mitis threads exhibited the highest extensibility ever recorded for the distal region of byssal threads. However, there were also interesting similarities in material properties across taxonomic groups. For instance, the threads of A. rigida and Modiolus modiolus Linnaeus both exhibited a prominent double-yield behavior, high stiffness combined with low extensibility, and similar correlations between stiffness and other thread properties. These similarities suggest that the thread properties of some semi-infaunal species may have evolved convergently. Further research on these patterns, along with biochemical analysis of threads which exhibit unusual properties like double-yield behavior, promises to contribute to both evolutionary biology and materials engineering.
Kinematics of horizontal and vertical caterpillar crawling
Authors: van Griethuijsen Linnea I. , Trimmer Barry A.
Published: May 2009

Unlike horizontal crawling, vertical crawling involves two counteracting forces: torque rotating the body around its center of mass and gravity resisting forward movement. The influence of these forces on kinematics has been examined in the soft-bodied larval stage of Manduca sexta. We found that crawling and climbing are accomplished using the same movements,with both segment timing and proleg lift indistinguishable in horizontal and vertical locomotion. Minor differences were detected in stride length and in the delay between crawls, which led to a lower crawling speed in the vertical orientation. Although these differences were statistically significant, they were much smaller than the variation in kinematic parameters between animals. The ability of Manduca to crawl and climb using the same movements is best explained by Manduca's relatively small size, slow speed and strong, controlled, passive grip made possible by its proleg/crochets.
Artistic Liberty and Slave Imagery: "Mark Twain's Illustrator," E. W. Kemble, Turns to Harriet Beecher Stowe
Authors: Sonstegard Adam
Published: May 2009

A comparison of Edward Windsor Kemble's illustrations for the first edition of Mark Twain's Adventures of Huckleberry Finn (1884–85) and for an 1891 edition of Harriet Beecher Stowe's Uncle Tom's Cabin (1852) shows that Kemble could render enslaved African Americans or impoverished European Americans as delineated individuals or as stereotypical figures, as he catered to audiences that had a stake in seeing these characters as unique personalities or as racialized "types." Marketing Twain's and Stowe's novels for mass audiences, Kemble mediated between literary authors who invest marginalized characters with distinct personalities and empowered, mainstream audiences who were less willing to accept individuality in minority figures. Kemble was not the egregiously racist exception for his time, but a reliable rule for the mainstream American publishing establishment; he typified Gilded Age readers who enjoyed the privileges of purchasing, reading, and illustrating literary representations of marginalized subjects—subjects who clearly did not enjoy such social privileges themselves. When Kemble takes artistic liberties in illustrating literary representations of slavery, then, he demonstrates graphically how Gilded Age readers were taking their own liberties reinterpreting these stories of slaves.
Neonatal Abstinence Syndrome
Authors: Burgos Anthony E. , Burke Bryan L.
Published: May 2009

Despite the growing knowledge of recognition, treatment, and outcomes, NAS continues to challenge clinicians. An increasing number of women receiving prescribed medications for chronic pain conditions and mental illness also have changed the population needing prenatal counseling and postnatal monitoring. NAS develops in more than 50% of all newborns exposed to narcotics in utero, but the signs of withdrawal remain nonspecific, and couplet care or rooming-in on postpartum wards often hinders monitoring and evaluation. Several abstinence scoring systems can assist nurses and physicians in assessing the severity of withdrawal and providing appropriate therapy. Medical therapy is recommended for severe cases, and several medications have proven safe and effective. Although the duration of therapy varies, medications can be titrated so infants can tolerate mild symptoms of withdrawal, and the process can be monitored with abstinence scores. This article reviews the signs of NAS from various substances, existing abstinence scoring systems, current treatment and weaning strategies, and relevant points for prenatal counseling.
A comparison of the cost of research in South Africa's public research and higher education institutions
Authors: Walwyn D.R.
Published: April 2009

Despite the importance of labour and overhead costs to both funders and performers of research in South Africa, there is little published information on the remuneration structures for researchers, technician and research support staff. Moreover, there are widely different pricing practices and perceptions within the public research and higher education institutions, which in some cases do not reflect the underlying costs to the institution or the inherent value of the research. In this article, data from the 2004/5 Research and Development Survey have been used to generate comparative information on the cost of research in various performance sectors. It is shown that this cost is lowest in the higher education institutions, and highest in the business sector, although the differences in direct labour and overheads are not as large as may have been expected. The calculated cost of research is then compared with the gazetted rates for engineers, scientists and auditors performing work on behalf of the public sector, which in all cases are higher than the research sector. This analysis emphasizes the need within the public research and higher education institutions for the development of a common pricing policy and for an annual salary survey, in order to dispel some of the myths around the relative costs of research, the relative levels of overhead ratios and the apparent disparity in remuneration levels.
Mitochondrial DNA diversity and population structure of a forest-dependent rodent, Praomys taitae (Rodentia: Muridae) Heller 1911, in the fragmented forest patches of Taita Hills, Kenya
Authors: Nyakaana Silvester , Tumusiime Christopher , Oguge Nicholas , Siegismund Hans R. , Arctander Peter , Muwanika Vincent
Published: April 2009

The population genetic structure of the forest-dependent rodent, Praomys taitae, sampled from nine indigenous forest fragments distributed over three ranges of the Taita Hills in Kenya, was determined using mitochondrial DNA (mtDNA) control region sequence variation. Thirty-three unique haplotypes were observed in a total sample of 132 individuals, whereas the number of different haplotypes per population ranged from two to 10. An overall low nucleotide diversity of 0.9% was observed in the total sample but varied widely between populations (0.2–1.3%). Significant genetic differentiation was observed in 30 of the 36 possible pair-wise comparisons between populations, while a hierarchical AMOVA revealed significant genetic subdivision between groups of populations on the three hill ranges of Dabida, Mbololo and Kyulu (FCT = 0.404, P less than 0.01), among populations on each of the hill ranges (FSC = 0.112, P less than 0.01) and among populations in the total sample (FST = 0.471, P less than 0.001). Demographic history analyses based on pair-wise nucleotide sequence mismatch distributions revealed that all the populations were in mutation-drift disequilibrium except the populations of the Kyulu and Ronge forest fragments.
Evaluation of changes in serum lipoprotein and apolipoprotein patterns in cows with ketosis
Authors: İleri-Büyükoğlu Tülay , Şahinduran Şima , Sezer Kenan , Güldür Tayfun
Published: May 2009

Objective—To detect changes in serum lipoprotein and apolipoprotein profiles via precipitation and electrophoresis in ketotic cows and in those cows treated with different methods.

Animals—21 cows with clinical and subclinical ketosis, 7 healthy cows in the early lactation period, and 7 healthy cows in the nonlactation period.

Procedures—Ketotic cows were allocated into 3 groups; the first group was treated with dextrose and dexamethasone, the second group with dextrose and prednisolone, and the third group with dextrose and insulin. The β and α lipoproteins were precipitated with dextran sulfate-magnesium chloride in ketotic cows after treatment and healthy cows in the nonlactation and lactation periods. The serum samples, precipitates, and supernatants were examined via agarose gel electrophoresis for detection of alterations in serum lipoproteins. Subsequently, alterations in serum apolipoproteins were detected via SDS-PAGE of precipitates.

Results—Compared with serum β and α lipoprotein concentrations in healthy cows during nonlactation, those in cows during lactation were higher; however, those in cows with ketosis were lower. The SDS-PAGE analysis of serum β lipoproteins revealed that apolipoprotein E (approx 36 and 40 kDa) decreased in ketotic cows, in comparison with healthy cows in the nonlactation and lactation periods, but increased after treatment. Decreases in apolipo-protein B (approx 222 kDa), apolipoprotein A-I (19 and 24 kDa), apolipoprotein A-IV (55 kDa), apolipoprotein C-III (8.8 and 10.2 kDa), and albumin (66 kDa) concentrations were detected in ketotic cows, in comparison with the healthy cows in the lactation period.

Conclusions and Clinical Relevance—Serum lipoprotein and apolipoproteins may routinely be determined via precipitation and electrophoresis in the diagnosis and treatment of ketosis.
Pharmacokinetics and bioavailability of metformin in horses
Authors: Hustace Jaime L. , Firshman Anna M. , Mata John E.
Published: May 2009

Objective—To determine pharmacokinetics and oral bioavailability of metformin in healthy horses.

Animals—4 adult horses.

Procedures—6 g of metformin was administered 3 times IV and PO (fed and unfed) to each horse, by use of a crossover design, with a 1-week washout period between treatments. Plasma metformin concentration was determined via high-pressure liquid chromatography.

Results—Mean ± SD distribution half-life of metformin following IV administration was 24.9 ± 0.4 minutes with a volume of distribution of 0.3 ± 0.1 L/kg. Mean area under the curve was 20.9 ± 2.0 h·μg/mL for IV administration; PO administration resulted in area under the curves of 1.6 ± 0.4 h·μg/mL in unfed horses and 0.8 ± 0.2 h·μg/mL in fed horses. Bioavailability was determined to be approximately 7.1 ± 1.5% in unfed horses and 3.9 ± 1.0% in fed horses. The maximal concentration following PO administration in unfed horses was 0.4 ± 0.1 μg/mL with a time at maximal concentration of 0.9 ± 0.1 hours. In fed horses, maximal concentration was reduced to 0.3 ± 0.04 μg/mL with a time at maximal concentration at 1.3 ± 0.3 hours.

Conclusions and Clinical Relevance—The low bioavailability of metformin may explain the reported lack of clinical success in improving insulin sensitivity with metformin treatment in horses. Dosages and dose intervals previously used may have been insufficient to achieve plasma concentrations of drug comparable to the therapeutic range achieved in humans. Therefore, a larger and more frequently administered dose may be required to fully evaluate efficacy of metformin in horses.
Prognostic indicators for nonambulatory cattle treated by use of a flotation tank system in a referral hospital: 51 cases (1997–2008)
Authors: Burton Alexandra J. , Nydam Daryl V. , Ollivett Theresa L. , Divers Thomas J.
Published: May 2009

Objective—To evaluate clinical variables assessed during the first 24 hours of hospitalization as prognostic indicators for nonambulatory cattle treated by use of a flotation tank.

Design—Retrospective case series.

Animals—51 nonambulatory cattle that underwent flotation treatment.

Procedures—Signalment, history, serum biochemical analyses, patient behavior during flotation, and outcome data were collected from medical records. Outcome was survival to discharge from the hospital or nonsurvival (death or euthanasia). Data were analyzed by use of Wilcoxon rank sum, Fisher exact, and χ2 tests.

Results—19 of 51 cattle survived. Survivors and nonsurvivors did not differ significantly with regard to median weight; age; stage of lactation; duration of recumbency prior to flotation; serum potassium, ionized calcium, or phosphate concentrations at admission to the hospital; or serum creatine kinase activity (value at admission to the hospital, highest value, and last recorded value). Cattle that were able to walk out of the tank after the first flotation treatment were 4.8 times as likely to survive as those that could not. Cattle that did not eat during flotation treatment were 1.9 times as likely to die as those that ate. Cattle that stood apparently normally on all limbs during the first flotation treatment were 2.9 times as likely to survive as those that had an asymmetric stance or were unable to stand.

Conclusions and Clinical Relevance—Results indicated that objective variables evaluated during the first 24 hours of hospitalization and flotation treatment are associated with outcome among nonambulatory cattle; findings might assist in logical decision making with respect to treatment options.
Can Violent (Re)offense be Predicted? A Review of the Role of the Clinician and Use of Actuarial Tests in Light of New Data
Authors: Zagar Robert John , Grove William M. , Busch Kenneth G. , Hughes John Russell
Published: May 2009

This article is an evaluation of established actuarial probation-parole tests in light of new data on violent and homicidal behavior. Probation–parole tests originally were developed by observing risks related with recidivism or return to court after release (i.e., the “danger” of releasing an individual) by following offenders in court records for up to 10 years. Commonly used probation-parole tests together comprise 82 distinct items related to characteristics of the offender: home, school, peers. Job, family, individual-medical, community, and court contacts. The risks for violence and homicide found by Zagar, et al. were compared with prior meta-analyses of risks with the criterion of violent delinquency. Bootstrapped logistic regressions in Zagar and colleagues' new data yielded highly accurate predictions of violence, showing that improved methods and sampling can lead to still higher accuracy than had been achieved by established probation-parole tests. A general discussion of the usefulness of actuarial tests and answers to challenges of their validity for decision making are provided.
Developing a dedicated cestode life cycle database: lessons from the hymenolepidids
Authors: Lefebvre F. , Georgiev B. , Bray R. , Littlewood D.
Published: April 2009

The Cestode Life Cycle Database (CLCdb) project was initiated in 2005 with the objective to develop a comprehensive and centralised resource to store, retrieve and analyse key information concerning tapeworm life cycles; e.g. morphogenesis, intermediate host identities, transmission patterns, etc. It constitutes the first electronic database to deal with complex life cycle information for any helminth taxon. Here we critically evaluate our experience after exhaustively entering data for our model group, the cyclophyllidean family Hymenolepididae. After providing basic statistics (530 consulted references; ∼ 230 ‘known’ life cycle), we identify future needs in turning the CLCdb into an open access monograph covering all cestode groups. We review the added benefits and potential utilities of the database for cestodologists and other users, including ecologists and veterinarians, and we call for specialist contributions. Since late 2007, a short version of the CLCdb has been available online, with basic functionalities and tools (www.nhm.ac.uk/research-curation/projects/cestode-life-cycle/index.html).
Overview of Research Progress on Peanut (Arachis hypogaea L.) Host Resistance to Aflatoxin Contamination and Genomics at the Guangdong Academy of Agricultural Sciences
Authors: Liang Xuanqiang , Zhou Guiyuan , Hong Yanbin , Chen Xiaopin , Liu Haiyan , Li Shaoxiong
Published: April 2009

Aflatoxin contamination in peanut is a serious and world-wide problem concerning food safety and human health. Plant-host resistance is a highly desirable tactic that can be used to manage this problem. This review summarizes research progress in peanut host resistance mechanisms to aflatoxin contamination at the Crops Research Institute, Guangdong Academy of Agricultural Sciences, Guangzhou, China. Through systematic resistance evaluations, germplasm lines resistant to Aspergillus flavus invasion have been identified and two resistant cultivars were developed and released in South China. The resistance has been associated with testa wax and presence of cutin layer, active oxygen and membrane lipid peroxidation, phytoalexin accumulation, and antifungal proteins in the peanut kernels. Functional genomics will be a valuable tool to understand the comprehensive mechanisms governing the resistance pathways. In this paper we also summarized the advances made by our group in the area of genomic research, especially in mining EST-SSRs, development of a genetic linkage map and QTLs mapping in the cultivated peanut species.
Synthetic polyploids of Tragopogon miscellus and T. mirus (Asteraceae): 60 Years after Ownbey's discovery
Authors: Tate Jennifer A. , Symonds V. Vaughan , Doust Andrew N. , Buggs Richard J. A. , Mavrodiev Evgeny , Majure Lucas C. , Soltis Pamela S. , Soltis Douglas E.
Published: May 2009

In plants, polyploidy has been a significant evolutionary force on both recent and ancient time scales. In 1950, Ownbey reported two newly formed Tragopogon allopolyploids in the northwestern United States. We have made the first synthetic lines of T. mirus and T. miscellus using T. dubius, T. porrifolius, and T. pratensis as parents and colchicine treatment of F1 hybrids. We also produced allotetraploids between T. porrifolius and T. pratensis, which are not known from nature. We report on the crossability between the diploids, as well as the inflorescence morphology, pollen size, meiotic behavior, and fertility of the synthetic polyploids. Morphologically, the synthetics resemble the natural polyploids with short‐ and long‐liguled forms of T. miscellus resulting when T. pratensis and T. dubius are reciprocally crossed. Synthetic T. mirus was also formed reciprocally, but without any obvious morphological differences resulting from the direction of the cross. Of the 27 original crosses that yielded 171 hybrid individuals, 18 of these lineages have persisted to produce 386 S1 progeny; each of these lineages has produced S2 seed that are viable. The successful generation of these synthetic polyploids offers the opportunity for detailed comparative studies of natural and synthetic polyploids within a nonmodel system.
Health-Related Quality of Life, Physical Function, Fatigue, and Disease Activity in Children with Established Polyarticular Juvenile Idiopathic Arthritis
Authors: RINGOLD SARAH , WALLACE CAROL A. , RIVARA FREDERICK P.
Published: May 2009

Objective.

To compare child self-report and parent/proxy report of health-related quality of life (HRQOL), disability, and fatigue in children with active polyarticular juvenile idiopathic arthritis (JIA) to that of children with inactive polyarticular JIA and to previous data from healthy controls.

Methods.

Cross-sectional survey of children with polyarticular JIA diagnosed and treated between 2000 to 2006 and their parent/proxy. The Childhood Health Assessment Questionnaire, Pediatric Quality of Life Inventory (PedsQL) Generic Core Scales, PedsQL Rheumatology Module, and PedsQL Multidimensional Fatigue Scale were administered. Disease activity data were collected from the physician clinic notes. Comparisons were performed with t tests. Correlations between patient and parent/proxy reports were measured with Pearson correlation coefficients.

Results.

Sixty children and/or their parents/proxies participated (79% response rate). Disease activity status was available for 52, and 32 met criteria for inactive disease (62%). Participants reported lower scores on the PedsQL Generic Core Scales (range 2.54–9.13 points lower) and the PedsQL Rheumatology Module (range 2.46–6.96 points lower) than those with inactive disease. Participants also reported lower scores on the PedsQL Multidimensional Fatigue Scale than did healthy controls, regardless of disease activity status (range 0.06–9.2 points lower).

Conclusion.

Although children in this cohort with polyarticular JIA and inactive disease reported HRQOL scores similar to those of healthy controls, children with polyarticular JIA and their parents/proxies tended to report more fatigue than controls, regardless of disease activity. Application of these measures prospectively to larger cohorts of children with JIA is needed to assess these differences.
Precision-to-Tolerance Capability: An Important Consideration in Tight Glucose Control
Authors: Prinzing Catherine , Rosenlund Sarah , Sukeena Vicki , Malinowski Cynthia , Wise Lowell C.
Published: May 2009

Objective To assess clinical implications of bias and variance of point-of-care glucometric measurements in cardiac surgery patients with wide variations in postoperative hematocrit.

Methods Point-of-care glucose measurements were compared with values from laboratory analysis of the same sample of whole blood obtained from cardiac patients early on postoperative days 1 and 2. Twenty nurses collected 89 arterial blood samples from 58 patients during a 4-month period. Bias was measured by using difference scores between paired measurements. Patients were grouped within 5% increments according to hematocrit, and analysis of variance was used to test for differences. Variation was analyzed by precision-to-tolerance analysis within 3 euglycemic tolerance ranges.

Results Laboratory glucose values were 62 to 224 mg/dL; point-of-care measures were 83 to 253 mg/dL. Bias was 10.85 mg/dL across all hematocrit groups. Pairs of laboratory and point-of-care glucose values differed significantly (t174 = 10.03; P < .001). Bias increased from −2.83 mg/dL for patients with hematocrits exceeding 39% to +16.71 mg/dL for patients with hematocrits between 20% and 24%. The standard deviation of difference scores was 11.59 mg/dL overall. The difference between 5% hematocrit groups was significant (F4 = 4.11; P = .004). Precision-to-tolerance capability ratios for specification limits of 70 to 300, 90 to 140, and 80 to 110 mg/dL were 0.30, 1.39, and 2.32, respectively.

Conclusions The direction of bias change between hematocrit groupings was the direction predicted in the manufacturer’s information. Precision-to-tolerance measures indicated that the point-of-care equipment was not suitable for testing glucose within the planned “tighter” glycemic standards.
Intracranial and Blood Pressure Variability and Long-Term Outcome After Aneurysmal Sub-arachnoid Hemorrhage
Authors: Kirkness Catherine J. , Burr Robert L. , Mitchell Pamela H.
Published: May 2009

Background Care of brain-injured patients in intensive care units has focused on maintaining arterial blood pressure and intracranial pressure within prescribed ranges. Research suggests, however, that the dynamic variability of these pressure signals provides additional information about physiological functioning and may reflect adaptive capacity.

Objectives To see if long-term outcomes can be predicted from variability of arterial blood pressure and intracranial pressure in patients with aneurysmal subarachnoid hemorrhage.

Methods Arterial blood pressure and intracranial pressure were monitored continuously for 4 days in 90 patients (74% women; mean age, 53 years) in an intensive care unit after subarachnoid hemorrhage. Variability of arterial blood pressure and intracranial pressure signals was calculated on 4 timescales: 24 hours, 1 hour, 5 minutes, and the difference of sequential 5-second means. The Extended Glasgow Outcome Scale was used to assess functional outcome 6 months after subarachnoid hemorrhage.

Results Pressure variability was better than mean pressure levels for predicting 6-month functional outcome. When initial neurological condition was controlled for, greater faster variability (particularly 5-second) was associated with better outcomes (typical P<.001), whereas greater 24-hour variability was associated with poorer outcomes (typical P<.001).

Conclusions The relationship between long-term functional outcome and variability of arterial blood pressure and intracranial pressure levels depends on the timescale at which the variability is measured. Because it is associated with better outcome, greater faster variability may reflect better physiological adaptive capacity.
An Efficient, Highly Diastereo‐ and Enantioselective Hetero‐
D
iels‐
A
lder Catalyst. Preparation of (2

S

,6

R

)‐6‐(

tert

‐Butyldimethyl‐Silyloxymethyl)‐2‐Methoxy‐2,5‐Dihydropyran
Authors: Chavez David E. , Jacobsen Eric N.
Published: April 2009

2‐(1‐Adamantyl)‐4‐methylphenol

(1
R
,2
S
)‐1‐Aminoindan‐2‐ol

(1
R
,2
S
)‐1‐[(3‐Adamantyl)‐2‐hydroxy‐5‐methylbenzylidenamino]indan‐2‐ol

Chromium(III) Cl complex

1‐Methoxy‐1,3‐butadiene

(2
S
,6
R
)‐6‐tert‐Butyldimethylsilyloxymethyl)‐2‐methoxy‐2,5‐dihydropyran
Lipase‐Catalyzed Resolution of 4‐Trimethylsilyl‐3‐Butyn‐2‐ol and Conversion of the (
R
)‐Enantiomer to (
R
)‐3‐Butyn‐2‐yl Mesylate and (
P
)‐1‐Tributylstannyl‐1,2‐Butadiene
Authors: Marshall James A. , Chobanian Harry
Published: April 2009

(R)‐4‐Trimethylsilyl‐3‐butyn‐2‐yl acetate

(S)‐4‐Trimethylsilyl‐3‐butyn‐2‐yl succinate

4‐Trimethylsilyl‐3‐butyn‐2‐ol

(R)‐4‐Trimethylsilyl‐3‐butyn‐2‐yl mesylate

Vinyl acetate

Diisobutylaluminum hydride

Butyllithium

Cuprous bromide‐dimethylsulfide complex

(
P
)‐1‐Tributylstannyl‐1, 2‐butadiene
Iridium‐Catalyzed Synthesis of Vinyl Ethers from Alcohols and Vinyl Acetate
Authors: Hirabayashi Tomotaka , Sakaguchi Satoshi , Ishii Yasutaka
Published: April 2009

Di‐μ‐bis(1,5‐cyclooctadiene)diiridium(I)

Sodium carbonate

p‐
Methoxyphenol

Vinyl acetate
1‐(

tert

‐Butylimino‐Methyl)‐1,3‐Dimethyl‐Urea Hydrochloride
Authors: Díaz David D. , Ripka Amy S. , Finn M. G.
Published: April 2009

1,3‐Dimethylurea

Acetyl chloride

tert
‐Butyl isocyanide
ortho

‐Formylation of Phenols; Preparation of 3‐Bromosalicylaldehyde
Authors: Hansen Trond Vidar , Skattebøl Lars
Published: April 2009

Triethylamine

Paraformaldehyde

2‐Bromophenol

Magnesium chloride

3‐Bromosalicylaldehyde
Preparation of 4‐Acetylamino‐2,2,6,6‐Tetramethylpiperidine‐1‐Oxoammonium Tetrafluoroborate, and the Oxidation of Geraniol to Geranial
Authors: Bobbitt James M. , Merbouh Nabyl
Published: April 2009

4‐Acetylamino‐2,2,6,6‐tetramethylpiperidine‐1‐oxonium tetrafluoroborate

4‐Acetylamino‐2,2‐6,6‐tetramethylpiperidine‐1‐oxoammonium perchlorate

4‐Acetamido‐TEMPO

Tetrafluoroboric acid

1‐Decanol

Hydrogen peroxide

4‐Amino‐2,2,6,6‐tetramethylpiperidinium acetate

Geraniol

Geranial

Sodium hypochlorite
(2

S

)‐(−)‐3‐
exo
‐(Morpholino)Isoborneol [(−)‐
MIB
]
Authors: Chen Young K. , Jeon Sang‐Jin , Walsh Patrick J. , Nugent William A.
Published: April 2009

Anti
‐(1‐
R
)‐(1)‐Camphorquinone 3‐oxime

(1
R
)‐(+)‐Camphor

(2
S
)‐(−)‐3‐exo‐Aminoisoborneol

Bis(2‐bromoethyl) ether

Lithium aluminum hydride

Isoamyl nitrite

Potassium‐
tert
‐butoxide

Triethylamine
Conversion of Arylalkylketones into Dichloroalkenes: (1‐Chloro‐4‐(2,2‐dichloro‐1‐methylethenyl)‐benzene)
Authors: Nenajdenko Valentine G. , Korotchenko Vasily N. , Shastin Alexey V. , Balenkova Elisabeth S.
Published: April 2009

Hydrazine hydrate

1‐(4‐Chlorophenyl)ethanone

1‐(4‐Chloropheny)ethanone hydrazone

Copper (I) chloride

Carbon tetrachloride
1,4‐Dioxene
Authors: Kreilein Matthew M. , Eppich James C. , Paquette Leo A.
Published: April 2009

Lead tetracetate

1,4‐Dioxane

2‐Acetoxy‐1,4‐dioxane

1,4‐Dioxene
Asymmetric Alcoholysis of Meso‐Anhydrides Mediated by Alkaloids
Authors: Bolm Carsten , Atodiresei Iuliana , Schiffers Ingo
Published: April 2009

Quinidine

Endo‐Bicyclo[2.2.1]hept‐5‐ene‐2,3‐dicarboxylic anhydride

Benzyl alcohol

Lithium triethylborohydride

Quinine
N

,

N

‐Dibenzyl‐

N

‐[1‐Cyclohexyl‐3‐(Trimethylsilyl)‐2‐Propynyl]‐Amine from Cyclohexanecarbaldehyde, Trimethylsilylacetylene and Dibenzylamine
Authors: Gommermann Nina , Knochel Paul
Published: April 2009

Trimethylsilylacetylene

Cyclohexanecarbaldehyde

Dibenzylamine

Copper(I) bromide

(
S
)‐Quinap

(
R
)‐(+)‐
N,N
‐Dibenzyl‐
N
‐[1‐cyclohexyl‐3‐(trimethylsilyl)‐2‐propynyl]‐amine

Tetra‐
n
‐butylammonium fluoride

N,N
‐Dibenzyl‐
N
‐(1‐cyclohexyl‐2‐propynyl)‐amine
Generation of Ynolate and

Z

‐Selective Olefination of Acylsilanes: (

Z

)‐2‐Methyl‐3‐Trimethylsilyl‐2‐Butenoic Acid
Authors: Shindo Mitsuru , Matsumoto Kenji , Shishido Kozo
Published: April 2009

1,2‐Dibromo‐1,1,2,2‐tetrachloroethane

Ethyl 2‐bromopropanoate

Ethyl 2,2‐dibromopropionate

Acetyltrimethylsilane
Synthesis of Acylsilanes from Morpholine Amides. Synthesis of 1‐(Dimethyl(phenyl)silyl)propan‐1‐One
Authors: Lettan Robert B. , Milgram Benjamin C. , Scheidt Karl A.
Published: April 2009

1‐Morpholinopropan‐1‐one

Morpholine

Propanoyl chloride

Chlorodimethylphenylsilane

1‐(Dimethyl(phenyl)silyl)propan‐1‐one
StereoselectiveIsoprenoid Chain Extension with Acetoacetate Dianion: (

E

,

E

,

E

)‐Geranylgeraniol From (

E

,

E

)‐Farnesol
Authors: Jin Yinghua , Roberts Frank G. , Coates Robert M.
Published: April 2009

(
E
,
E
)‐ Farnesol

Methanesulfonyl chloride

Ethylacetoacetate

Diethylchlorophosphate

Diisobutylaluminum hydride
Synthesis of Terminal 1,3‐Diynes via Sonogashira Coupling of Vinylidene Chloride Followed by Elimination. Preparation of 1,3‐Decadiyne
Authors: Kohnen Amanda L. , Danheiser Rick L.
Published: April 2009

n
‐Butylamine

1‐Octyne

Vinylidene chloride

2‐Chloro‐1‐decen‐3‐yne

Copper (I) iodide

1, 3‐Decadiyne

Diisopropylamine
Synthesis of Ynamides by

N

‐Alkynylation of Amine Derivatives. Preparation of

N

‐Allyl‐

N

‐(Methoxycarbonyl)‐1,3‐Decadiynylamine
Authors: Kohnen Amanda L. , Dunetz Joshua R. , Danheiser Rick L.
Published: April 2009

Allylamine

Methyl chloroformate

N
‐(Methoxycarbonyl)‐2‐propenylamine

1,3‐Decadiyne

N
‐Bromosuccinimide

Potassium hexamethyldisilazide

Copper(I) iodide
(

S

)‐(+)‐Neomenthyldiphenylphosphine in Nickel‐Catalyzed Asymmetric Reductive Coupling of Alkynes and Aldehydes: Enantioselective Synthesis of Allylic Alcohols and α‐Hydroxy Ketones
Authors: Van Dyke Aaron R. , Miller Karen M. , Jamison Timothy F.
Published: April 2009

Ni(cod)2

(
S
)‐(+)‐Neomenthyldiphenylphosphine

Triethylborane

Dimethylimidizolidinone

1‐Phenyl‐1‐butyne

(
R
)‐(
E
)‐2‐Benzylidiene‐1‐cyclohexyl‐butan‐1‐ol

(
R
)‐Butan‐2‐one

Dimethylsulfide
Preparation ofN‐p‐Tolylsulfonyl‐(E)‐1‐Phenylethylideneimine
Authors: Ruano José Luis García , Alemán José , Parra Alejandro , Cid M. Belén
Published: April 2009

N‐p‐Toluenesulfinamide

Acetophenone

Ethanol, 1‐phenyl

Ethanol, titanium

N‐p‐Tolylsulfinyl‐(E)‐1‐phenylethylideneimine

Benzenecarboperoxic acid, 3‐chloro

N‐p‐Tolylsulfonyl‐(E)‐phenylethylideneimine
Preparation of a Trisamidomolybdenum(
VI
) Propylidyne Complex – A Highly Active Catalyst Precursor For Alkyne Metathesis
Authors: Zhang Wei , Lu Yunyi , Moore Jeffrey S.
Published: April 2009

Sodium
tert
‐butoxide

2‐(Dicyclohexylphosphino)biphenyl

Tris(dibenzylideneacetone)dipalladium(0)

Tert
‐Butylamine

5‐Bromo‐
m
‐xylene

N
‐(3,5‐Dimethylphenyl)‐
tert
‐butylamine

Butyllithium

Lithium
N
‐(3,5‐dimethylphenyl)‐
tert
‐butylamide etherate

Molybdenum(V) chloride

Tris[
N‐tert
‐butyl)(3,5‐dimethylphenyl)‐amido]molybdenum(III)

1,1‐Dichloropropane

Trisamidomolybdenum(VI) propylidyne

N
‐Nitrophenol

1‐Phenyl‐1‐butyne
Electrophilic Cyclization withN‐Iodosuccinimide: Preparation of 5‐(4‐Bromophenyl)‐3‐Iodo‐2‐(4‐Methylphenyl)Furan
Authors: Sniady Adam , Morreale Marco S. , Dembinski Roman
Published: April 2009

5‐(4‐Bromophenyl)‐3‐iodo‐2‐(4‐methylphenyl)furan

2‐(4‐Bromophenyl)oxirane

4‐Ethynyltoluene

Lithium diisopropylamide

1‐(4‐Bromophenyl)‐4‐methylphenyl)but‐3‐yn‐1‐ol

Chromium trioxide

1‐(4‐Bromophenyl)‐4‐methylphenyl)but‐3‐yn‐1‐one

N‐Isosuccinamide
Selective
Pd
‐Catlyzed Aminations on Chloroiodopyridines: Synthesis of Ethyl 4‐[(6‐Chloropyridin‐3‐
YL
)Amino]Benzoate
Authors: Rombouts Geert , Maes Bert U.W. , Jonckers Tim H.M. , Loones Kristof T.J.
Published: April 2009

Palladium(II) acetate

Rac. BINAP

2‐Chloro‐5‐iodopyridine

Ethyl 4‐aminobenzoate

Cesium carbonate
A Practical Procedure for Carbonyl α‐Oxidation: Synthesis of (2‐Benzoyloxy)‐1,4‐Cyclohexanedione
Mono
‐Ethylene Ketal
Authors: Jones Teyrnon C. , Tomkinson Nicholas C. O.
Published: April 2009

Benzoic acid

Carbonyldiimadazole

N
‐Methylhydroxylamine hydrochloride

N
‐Methyl‐
O
‐benzoylhydroxylamine hydrochloride

1,4‐Cyclohexanedione (mono)ethylene ketal

(2‐Benzoyloxy)‐1,4‐cyclohexandione (mono)ethylene ketal
Synthesis of Electron‐Deficient Secondary Phosphine Oxides and Secondary Phosphines: Bis[3,5‐Bis(Trifluoromethyl)phenyl]phosphine Oxide and Bis[3,5‐Bis(Trifluoromethyl)Phenyl]Phosphine
Authors: A. Busacca Carl , C. Lorenz Jon , Sabila Paul , Haddad Nizar , H. Senanyake Chris
Published: April 2009

Bis[3,5‐bis(trifluoromethyl)phenyl]‐phosphine oxide

3,5‐Bis(trifluoromethyl)bromobenzene

Diethyl phosphate

Bis[3,5‐bis(trifluoromethyl)phenyl]phosphine
Preparation of Substituted 5‐Aziandoles: Methyl 4‐Chloro‐1

H

‐Pyrrolo[3,2‐

C

]Pyridine‐2‐Carboxylate
Authors: Roy Patrick , Boisvert Michel , Leblanc Yves
Published: April 2009

Methyl azidoacetate

Methyl bromoacetate

Sodium azide

Methyl (2
Z
)‐2‐azido‐3‐(2‐chloropyridin‐3‐yl)acrylate

2‐Chloro‐3‐pyridinecarboxaldehyde

Methyl 4‐chloro‐1
H
‐pyrrolo[3,2‐c]pyridine2‐carboxylate

Mesitylene
Synthesis of Multi‐Functionalized Ketones through the Fukuyama Coupling Reaction Catalyzed by Pearlman's Catalyst: Preparation of Ethyl 6‐Oxotridecanoate
Authors: Mori Yoshikazu , Seki Masahiko
Published: April 2009

Octanoic acid

N,N‐Dimethylaminopyridine

1,3‐Propanediamine

Ethanethiol

2‐Dibromoethane

Chlorotrimethylsilane

Ethyl 5‐iodopentanoate

Palladium hydroxide

Ethyl pentanoate
Protection of Alcohols Using 2‐Benzyloxy‐1‐Methylpyridinium Trifluoromethanesulfonate: Methyl (
R
)‐(−)‐3‐Benzyloxy‐2‐Methyl Propanote
Authors: Poon Kevin W. C. , Albiniak Philip A. , Dudley Gregory B.
Published: April 2009

Benzyl alcohol

2‐Chloropyridine

2‐Benzyloxypyridine

2‐Benzyloxy‐1‐methylpyridinium trifluoromethanesulfonate

Methyl (R)‐(−)‐3‐benzyloxy‐2‐methyl propanoate

Magnesium oxide

Methyl (R)‐(−)‐3‐hydroxy‐2‐methyl propionate
Chiral Lithium Amide Base Desymmetrization of a Ring Fused Imide: Formation of (3
a

S

, 7
a

S

)‐2‐[2‐(3,4‐Dimethoxyphenyl)‐Ethyl]‐1,3‐Dioxo‐Octahydro‐Isoindole‐3
a
‐Carboxylic Acid Methyl Ester
Authors: Rodeschini Vincent , Simpkins Nigel S. , Zhang Fengzhi
Published: April 2009

Aqueous glyoxal solution

Phenylmagnesium chloride

1 R‐‐(+)‐Phenylethylamine

1(
S
),2(
S
)‐Diphenyl‐
N,N′
‐bis[1‐R‐phenyl‐ethyl]‐ethane‐1,2‐diamine

Chlorohexanedicarboxylic anhydride

2‐(3,4‐Dimethoxyphenyl)ethylamine

(3a,
S
,7a
R
)‐2‐[2‐(3,4‐Dimethoxyphenyl)‐ethyl]hexahydro‐isoindole‐1,3‐dione

Butyl lithium

Methyl cyanoformate

(3a
S
, 7a
S
)‐2‐[2‐(3,4‐Dimethoxyphenyl)‐ethyl]‐1,3‐diox‐octahydroisoindole‐3a‐carboxylic acid methyl ester
Synthesis of an

N

‐Substituted Lactam Using An Intramolecular Schmidt Reaction: Formation of 2,3,11,11a‐Tetrahydro‐1

H

‐Benzo[d]Pyrrolo[1,2‐a]Azepin‐5(6

H

)‐One
Authors: Grecian Scott , Aubé Jeff
Published: April 2009

Dimethyl carbonate

Methyl 2‐oxo‐1,2,3,4‐tetrahydronaphthalene‐1‐carboxylate

Sodium hydride

Beta‐Tetralone

Diisopropylamine

Butyllithium

Sodium iodide

Sodium azide

3‐(3′‐Azidopropyl)‐3,4‐dihydronaphthalen‐2(1
H
)‐one

Trifluoroacetic acid

2,3,11,11a‐Tetrahydro‐1
H
‐benzo[d]pyrrolo[1,2a]alzepin‐5(6
H
)‐one
Practical Synthesis of a Chiral Ynamide: (R)‐4‐Phenyl‐3‐(2‐Triisopropylsilyl‐Ethynyl)Oxazolidin‐2‐One
Authors: Sagamanova I. K. , Kurtz K. C. M. , Hsung R. P.
Published: April 2009

n‐Butyllithium

Trispropylsilylacetylene

Copper sulfate pentahydrate

1‐Bromo‐2‐triisopropylsilyl‐ethyne

R‐Phenyloxazolidinone

1,10‐Phenanthroline
Oriented Monolayer Film of Gd2O3:0.05 Eu Crystallites: Quasi‐Topotactic Transformation of the Hydroxide Film and Drastic Enhancement of Photoluminescence Properties
Authors: Hu Linfeng , Ma Renzhi , Ozawa Tadashi C. , Sasaki Takayoshi
Published: April 2009

Auf den Film gebannt: Eine halbtransparente und intensiv lumineszierende Monoschicht aus ausgerichteten plättchenförmigen Gd2O3:0.05 Eu‐ Kristalliten entsteht beim Tempern der Hydroxidfilm‐Vorstufe (siehe Schema). Die Photolumineszenzeigenschaften des umgewandelten Films sind deutlich besser als die des Hydroxidfilms, und sie sind viel ausgeprägter als die der analogen Gd2O3:0.05 Eu‐Pulverprobe.

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Total Synthesis of (+)‐Dibromophakellin
Authors: Imaoka Takuya , Iwamoto Osamu , Noguchi Kei‐ichi , Nagasawa Kazuo
Published: April 2009

Zwei Mitglieder einer Familie mariner Pyrrol‐Imidazol‐Alkaloide – (+)‐Dibromphakellin und das nichtnatürliche Kongener (+)‐Phakellin – wurden enantioselektiv aus 4‐Hydroxy‐L‐prolin synthetisiert. Das chirale Aminal an C10 ließ sich mithilfe einer [3,3]‐sigmatropen Overman‐Umlagerung eines Enamids effizient aufbauen (siehe Schema).

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In Situ Enamine Activation in Aqueous Salt Solutions: Highly Efficient Asymmetric Organocatalytic Diels–Alder Reaction of Cyclohexenones with Nitroolefins
Authors: Xu Dan‐Qian , Xia Ai‐Bao , Luo Shu‐Ping , Tang Jie , Zhang Shuai , Jiang Jun‐Rong , Xu Zhen‐Yuan
Published: April 2009

Deep‐sea Diels–Alder: The asymmetric organocatalytic Diels–Alder reaction of cyclohexenones with aromatic nitroolefins can be carried out in seawater and brine. The reaction proceeds by an in situ enamine activation involving a one‐step concerted addition pathway (see scheme).

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