bluuebunny/crossref_metadata_2025 huggingface dataset:
Premorbid functioning and treatment response in recent-onset schizophrenia
Authors: Rabinowitz Jonathan , Harvey Philip D. , Eerdekens Marielle , Davidson Michael
Published: July 2006

Background

Investigating the relationship between premorbid functioning and treatment response in schizophrenia is relevant to understanding the illness and predicting treatment outcomes.

Aims

To examine the relationship between premorbid characteristics and treatment response of people with recent-onset schizophrenia.

Method

Data came from a large, double-blind trial of recent-onset psychosis treated with a flexible dose of risperidone or haloperidol. Median treatment length was 206 days. Premorbid functioning was categorised using the Cannon-Spoor Premorbid Adjustment Scale.

Results

There were significant differences between the premorbid groups on change on the Positive and Negative Syndrome Scale, Clinical Global Impression severity and cognitive functioning and Extrapyramidal Symptoms Rating Scale. Patients in the ‘stable–good’ premorbid group (n=251) improved more than those in the ‘stable–poor’ (n=198) and ‘declining’ (n=81) groups. The ‘stable–good’ group received the lowest doses of antipsychotic and had the least extrapyramidal symptoms. Patients in the declining’ group had the highest dosages and the most extrapyramidal symptoms.

Conclusions

In first-episode psychosis good premorbid functioning is associated with better response to treatment and fewer extrapyramidal symptoms.
Driving, dementia and the Driver and Vehicle Licensing Agency: a survey of old age psychiatrists
Authors: Naidu Anitha , McKeith Ian G.
Published: June 2006

Aims and Method

We surveyed old age psychiatrists in the north-east of England to determine what they considered relevant indicators of driving ability. The survey asked about their satisfaction with the current Driver and Vehicle Licensing Agency (DVLA) procedure of assessing competence to drive in patients with dementia and how they thought this could be improved.

Results

Fifty-seven out of 76 psychiatrists (75%) responded; 26 (45%) respondents thought the forms issued by the DVLA were unsatisfactory but 32 (57%) were satisfied with the eventual decisions made about individual patients. Factors thought to be relevant indicators of driving ability were occupational therapy (n=46, 81%), neuropsychological assessments (n=43, 75%) and carer's report of driving (n=48, 84%). Factors thought not to be relevant were patient's report of driving ability (n=13, 23%) and the Mini Mental State Examination (n=21, 38%).

Clinical Implications

The current system for determining driving ability in people with cognitive impairment and dementia was felt to be unsatisfactory. A multidisciplinary approach and use of on-road driving assessments may improve decision-making.
Formulas Calculating Creatinine Clearance Are Inadequate for Determining Eligibility for Cisplatin-Based Chemotherapy in Bladder Cancer
Authors: Raj Ganesh V. , Iasonos Alexia , Herr Harry , Donat Sherri Machele
Published: June 2006

Purpose

Efficacy of formulas calculating creatinine clearance (CrCl) to determine renal function eligibility (CrCl > 60 mL/min) for cisplatin-based chemotherapy has not been examined adequately in the bladder cancer population. We hypothesize these formulas may underestimate measured CrCl, and therefore the eligibility for cisplatin-based chemotherapy.

Patients and Methods

A database of 208 patients with unresectable or metastatic bladder cancer treated on protocol at Memorial Sloan-Kettering Cancer Center (New York, NY) with cisplatin-based chemotherapy between 1983 and 1994 was examined retrospectively. The association between measured and calculated CrCl and the ability to complete three cycles (minimum therapeutic) of chemotherapy was examined.

Results

Baseline measured CrCl was less than 60 mL/min in 16% compared with 12% to 44% using various formulas. Concordance between calculated and measured CrCl less than 60 mL/min was poor (range of κ, 0.14 to 0.38). In patients older than age 65, 22% had a measured CrCl less than 60 mL/min, compared with 10% to 63% calculated using various formulas. Overall, 80% completed at least three cycles of cisplatin-based chemotherapy. The ability to complete at least three cycles was statistically significantly related with a measured CrCl more than 60 mL/min (P = .02), but not with calculated CrCl more than 60 mL/min.

Conclusion

Current formulas estimating CrCl tend to underestimate measured CrCl, especially in those older than 65 years. Depending on the formula used, up to 44% who actually received cisplatin-based chemotherapy based on measured CrCl would be deemed ineligible at present, potentially affecting survival outcomes. Methodology for determining CrCl and/or renal eligibility for cisplatin-based chemotherapy in patients with bladder cancer should be re-examined.
Renal Cell Carcinoma Recurrence After Nephrectomy for Localized Disease: Predicting Survival From Time of Recurrence
Authors: Eggener Scott E. , Yossepowitch Ofer , Pettus Joseph A. , Snyder Mark E. , Motzer Robert J. , Russo Paul
Published: June 2006

Purpose

Prognostic factors for patients with metastatic renal cell carcinoma (RCC) are well established. However, the risk profile is unknown for patients with recurrent RCC after a nephrectomy for localized disease.

Patients and Methods

From January 1989 to July 2005, we identified patients with localized RCC treated by nephrectomy who subsequently developed recurrent disease. We applied a validated prognostic scoring system previously developed for patients with metastatic RCC. Each patient was given a total risk score of 0 to 5, with one point for each of five prognostic variables (recurrence < 12 months after nephrectomy, serum calcium > 10 mg/dL, hemoglobin < lower limit of normal, lactate dehydrogenase > 1.5× upper limit of normal, and Karnofsky performance status < 80%). Patients were categorized into low- (score = 0), intermediate- (score = 1 to 2), and high-risk subgroups (score = 3 to 5).

Results

Our final cohort included 118 patients, with a median survival time of 21 months from the time of recurrence. Median follow-up time for survivors was 27 months. Overall survival was strongly associated with risk group category (P < .0001). Low-risk, intermediate-risk, and high-risk criteria were fulfilled in 34%, 50%, and 16% of patients, respectively. Median survival time for low-risk, intermediate-risk, and high-risk patients was 76, 25, and 6 months, respectively. Two-year overall survival rates for low-risk, intermediate-risk, and high-risk patients were 88% (95% CI, 77% to 99%), 51% (95% CI, 37% to 65%), and 11% (95% CI, 0% to 24%), respectively.

Conclusion

At disease recurrence after nephrectomy for localized disease, a scoring system based on objective clinical and laboratory data provides meaningful risk stratification for both patient counseling and clinical trial entry.
Neoadjuvant Treatment of Regional Stage IIIB Melanoma With High-Dose Interferon Alfa-2b Induces Objective Tumor Regression in Association With Modulation of Tumor Infiltrating Host Cellular Immune Responses
Authors: Moschos Stergios J. , Edington Howard D. , Land Stephanie R. , Rao Uma N. , Jukic Drazen , Shipe-Spotloe Janice , Kirkwood John M.
Published: June 2006

Purpose

Adjuvant high-dose interferon-alfa-2b (HDI) improves disease-free and overall survival in patients with high-risk melanoma. However, its mechanism of action is largely unknown. Therefore, HDI was investigated in the neoadjuvant setting to assess clinical and pathologic responses after 4 weeks of HDI and to perform immunohistochemical evaluation of immune cell subsets and melanoma-associated antigens.

Patients and Methods

Patients with palpable regional lymph node metastases from melanoma (American Joint Committee on Cancer stage IIIB-C) underwent surgical biopsy at study entry and then received standard intravenous HDI (20 million units/m2, 5 days per week) for 4 weeks followed by complete lymphadenectomy and standard maintenance subcutaneous HDI (10 million units/m2 3 times per week) for 48 weeks. Biopsy samples were obtained before and after intravenous HDI and subjected to immunohistochemical analysis as well as routine pathologic study.

Results

Twenty patients were enrolled, and biopsy samples were informative for 17. Eleven patients (55%) demonstrated objective clinical response, and 3 patients (15%) had complete pathologic response. At a median follow-up of 18.5 months (range, 7 months to 50 months) 10 patients had no evidence of recurrent disease. Clinical responders had significantly greater increases in endotumoral CD11c+ and CD3+ cells and significantly greater decreases in endotumoral CD83+ cells compared with nonresponders. No changes in the expression of melanoma-associated lineage antigens, tumor cell proliferation, angiogenesis, or apoptosis were evident.

Conclusion

Neoadjuvant HDI is highly effective for the treatment of palpable stage IIIB-C melanoma, and the findings of this study implicate an indirect immunomodulatory mechanism rather than a direct antitumor mechanism.
Health-Related Quality of Life Measurement in Randomized Clinical Trials in Surgical Oncology
Authors: Blazeby Jane M. , Avery Kerry , Sprangers Mirjam , Pikhart Hynek , Fayers Peter , Donovan Jenny
Published: June 2006

Purpose

There is debate about the value of measuring health-related quality of life (HRQL) in clinical trials in oncology because of evidence suggesting that HRQL does not influence clinical decisions. Analysis of HRQL in surgical trials, however, may inform decision making because it provides detailed assessment of the immediate detrimental short-term impact of surgery on HRQL that needs to be considered against the long-term survival benefits and functional outcomes of surgery. This study evaluated whether HRQL in randomized trials in surgical oncology contributes to clinical decision making.

Methods

A systematic review identified randomized trials in surgical oncology with HRQL. Trials were evaluated independently by two reviewers and the value of HRQL in clinical decision making was categorized in three ways: whether trial investigators reported that HRQL influenced final treatment recommendations, whether trial investigators reported that HRQL would be useful for informed consent, and whether HRQL was assessed robustly according to predefined criteria.

Results

Thirty-three randomized trials with valid HRQL questionnaires were identified; 22 (67%) concluded that HRQL outcomes influenced treatment decisions or provided valuable data for informed consent, and seven of these trials had robust HRQL design. Another five trials had robust HRQL design but investigators reported that HRQL outcomes were not clinically important enough to influence treatment recommendations.

Conclusion

In surgical trials in oncology, HRQL informed clinical decision making. It is recommended that HRQL be included in relevant surgical trials, and that information be used to inform clinicians and patients about the impact of surgery on short- and long-term HRQL.
Role of Tyrosine Kinase Receptors in Angiotensin II AT2 Receptor Signaling: Involvement in Neurite Outgrowth and in p42/p44mapk Activation in NG108-15 Cells
Authors: Plouffe Bianca , Guimond Marie-Odile , Beaudry Hélène , Gallo-Payet Nicole
Published: June 2006

NG108–15 cells, which have a rounding-up morphology when cultured in serum-supplemented medium, extend neurites when stimulated for 3 d with angiotensin II (Ang II). The aim of the present study was to investigate whether growth factor receptors are necessary for mediating the effects of Ang II. A 3-d treatment with AG879, an inhibitor of nerve growth factor receptor TrkA, strongly affected neurite outgrowth and phosphorylation of p42/p44mapk induced by Ang II. PD168393, an inhibitor of epidermal growth factor (EGF) receptor slightly decreased Ang II-induced neurite outgrowth, whereas AG213, an inhibitor of both platelet-derived growth factor receptor and EGF receptor, stimulated neurite outgrowth and p42/p44mapk phosphorylation on its own, without affecting further stimulation with Ang II. Moreover, Ang II induced the phosphorylation of TrkA (maximum at 5 min of incubation in the presence of serum or at 20 min in cells depleted in serum for 2 h) and a rapid increase in Rap1 activity, both effects abolished in cells preincubated with 10 μm AG879. In summary, the present results demonstrate that AT2 receptor-induced sustained activation of p42/p44mapk and corresponding neurite outgrowth are mediated by phosphorylation of the nerve growth factor TrkA receptor. However, the results also point out that the presence of other growth factors, such as EGF or PDFG, may interfere with the effect of Ang II. Altogether, the current findings clearly indicate that the effects of the AT2 receptor on neurite outgrowth dynamics are modulated by the presence of growth factors in the culture medium.
Spot 14: A Marker of Aggressive Breast Cancer and a Potential Therapeutic Target
Authors: Kinlaw William B. , Quinn Jennifer L. , Wells Wendy A. , Roser-Jones Christopher , Moncur Joel T.
Published: June 2006

Spot 14 (S14) is a nuclear protein that communicates the status of dietary fuels and fuel-related hormones to genes required for long-chain fatty acid synthesis. In mammary gland, S14 is important for both epithelial proliferation and milk fat production. The S14 gene is amplified in some breast cancers and is strongly expressed in most. High expression of S14 in primary invasive breast cancer is conspicuously predictive of recurrence. S14 mediates the induction of lipogenesis by progestin in breast cancer cells and accelerates their growth. Conversely, S14 knockdown impairs de novo lipid synthesis and causes apoptosis. We found that breast cancer cells do not express lipoprotein lipase (LPL) and hypothesize that they do not have access to circulating lipids unless the local environment supplies it. This may explain why primary breast cancers with low S14 do not survive transit from the LPL-rich mammary fat pad to areas devoid of LPL, such as lymph nodes, and thus do not appear as distant metastases. Thus, S14 is a marker for aggressive breast cancer and a potential target as well. Future effort will center on validation of S14 as a therapeutic target and producing antagonists of its action.
A novel secreted endonuclease from Culex quinquefasciatussalivary glands
Authors: Calvo Eric , Ribeiro José M. C.
Published: June 2006

Previous analysis of the salivary gland transcriptome of Culex quinquefasciatus showed the potential presence of an endonuclease with sequence similarities to shrimp, crab and two tsetse salivary proteins. Indeed, not only was the cloned cDNA shown to encode an active double-stranded endonuclease, but also the same activity was demonstrated to be secreted by salivary glands of Cx. quinquefasciatus. Preliminary studies with salivary gland extracts confirmed the presence of a highly active nuclease. This enzyme was shown to be present in the saliva of female mosquitoes by allowing starved mosquitoes to probe DNA-containing agarose gel. The recombinant Cx. quinquefasciatus endonuclease (CuquEndo) produced in mammalian cells showed no sequence specificity for DNA substrate except that it only cleaves double-stranded DNA. Recombinant Cx. quinquefasciatusendonuclease was active in the presence of Mg2+ ions at pH 7.0-8.0,but no endonuclease activity was detected in the presence of calcium ions. The final hydrolysis products of this enzyme, detected by ion exchange chromatography, yielded DNA fragments ranging form 8-12 base pairs. Although endonucleases have been associated with a variety of cellular functions, their role in mosquito saliva is not clear. This female-specific secreted endonuclease may assist blood meal intake by lowering the local viscosity created by the release of host DNA in the bite site and/or acting as an indirect anticoagulant factor by producing a defibrotide-like mixture of DNA haptamers.
Effects of moderate and substantial hypoxia on erythropoietin levels in rainbow trout kidney and spleen
Authors: Lai Jimmy C. C. , Kakuta Izuru , Mok Helen O. L. , Rummer Jodie L. , Randall David
Published: June 2006

Erythropoietin (EPO) is a glycoprotein hormone that regulates the proliferation and differentiation of erythroid progenitor cells in mammals. Although EPO has been identified in fish, the specific function and effects of hypoxia have not been investigated previously. In this study, we have demonstrated a relationship between increases in renal EPO levels and decreases in spleen EPO levels and spleen-somatic index (SSI), with increases in haemoglobin (Hb) concentration in the blood during hypoxia exposure in rainbow trout. Splenic contraction and the subsequent red blood cell release accounts for the initial increase in Hb concentration in the blood, whereas EPO action probably accounts for the later increases in hemoglobin concentration in the blood. Our data indicate that fish and mammalian erythropoietic systems are similar in response to hypoxia, in that erythropoiesis in fish is influenced by EPO.
Multidimensional analysis of suction feeding performance in fishes: fluid speed, acceleration, strike accuracy and the ingested volume of water
Authors: Higham Timothy E. , Day Steven W. , Wainwright Peter C.
Published: June 2006

Suction feeding fish draw prey into the mouth using a flow field that they generate external to the head. In this paper we present a multidimensional perspective on suction feeding performance that we illustrate in a comparative analysis of suction feeding ability in two members of Centrarchidae, the largemouth bass (Micropterus salmoides) and bluegill sunfish(Lepomis macrochirus). We present the first direct measurements of maximum fluid speed capacity, and we use this to calculate local fluid acceleration and volumetric flow rate. We also calculated the ingested volume and a novel metric of strike accuracy. In addition, we quantified for each species the effects of gape magnitude, time to peak gape, and swimming speed on features of the ingested volume of water. Digital particle image velocimetry (DPIV) and high-speed video were used to measure the flow in front of the mouths of three fish from each species in conjunction with a vertical laser sheet positioned on the mid-sagittal plane of the fish. From this we quantified the maximum fluid speed (in the earthbound and fish's frame of reference), acceleration and ingested volume. Our method for determining strike accuracy involved quantifying the location of the prey relative to the center of the parcel of ingested water. Bluegill sunfish generated higher fluid speeds in the earthbound frame of reference, accelerated the fluid faster, and were more accurate than largemouth bass. However, largemouth bass ingested a larger volume of water and generated a higher volumetric flow rate than bluegill sunfish. In addition, because largemouth bass swam faster during prey capture, they generated higher fluid speeds in the fish's frame of reference. Thus, while bluegill can exert higher drag forces on stationary prey items, largemouth bass more quickly close the distance between themselves and prey. The ingested volume and volumetric flow rate significantly increased as gape increased for both species, while time to peak gape had little effect on the volume. However, peak gape distance did not affect the maximum fluid speed entering the mouth for either species. We suggest that species that generate high fluid speeds in the earthbound frame of reference will commonly exhibit small mouths and a high capacity to deliver force to buccal expansion,while species that ingest a large volume of water and generate high volumetric flow rates will have larger buccal cavities and cranial expansion linkage systems that favor displacement over force delivery.
Evaluating the Interlobe Clearance and Determining the Sizes and Shapes of All the Leakage Paths for Twin-Screw Vacuum Pump
Authors: Fong Z H , Huang F C
Published: June 2006

The maximum sphere method and the minimum cross-section method are proposed to calculate the interlobe clearance between two mating screw rotors and to determine the shapes and sizes of all the leakage paths. These two methods are inspired by the red-lead and tooth-contact pattern and can be used to evaluate the interlobe leakage and to design the mating rotor profiles. The combined results of these two methods provide the basis for an exact evaluation of the fluid leakage, and this feature increases flexibility in geometrical designing and manufacturing of the screw rotors. These methods are also suitable for non-conjugate rotors and contribute to thermal analysis and optimum programming.
Thickness Optimization of Axisymmetric Tube by Three-Dimensional Finite-Element Analysis for High-Flexural Rigidity
Authors: Kuboki T , Makiyama T , Murata M
Published: June 2006

A numerical method is proposed for optimizing the wall thickness distribution of axisymmetric tube using three-dimensional finite-element method. It is essential to put intermediate nodes between adjustable nodes in the method. Using the proposed method, the wall thickness distributions are optimized to realize high-flexural rigidity under the condition that volume is constant. It is revealed that the constraint condition has significant effect on the optimized geometry. When the end of the tube is constrained completely, it is not necessary to increase the thickness at the end. In contrast, when the end is not constrained, the thickness must be increased substantially. Therefore, it is important to take the constraint condition of the tube into consideration for tube geometry optimization. It is also demonstrated quantitatively that the geometry optimization realizes the volume reduction of the tube from the point of flexural rigidity per volume. Moreover, the feasibility to produce the optimized tube is studied using a unique extrusion method with tapered mandrel, which has been proposed by the authors. In this unique method, the wall thickness is controlled arbitrarily by positioning the tapered mandrel during extrusion.
On the Performance of a Cascade of Turbine Rotor Tip Section Blading in Wet Steam. Part 5: Theoretical Treatment
Authors: Bakhtar F , Henson R J K , Mashmoushy H
Published: June 2006

During the course of expansion of steam in turbines, the fluid first supercools and then nucleates to become a two-phase mixture. The formation and behaviour of the liquid create problems that lower the performance of turbine wet stages and the mechanisms underlying these are insufficiently understood. Steam turbines play a dominant role in the generation of the main electrical power supply, and the economic returns on improved performance are substantial. This article is the last of a set and describes the theoretical part of an investigation into the performance of a turbine rotor tip section profile in wet steam. The experimental results are described in the earlier parts of the paper.

To describe the behaviour of the flow theoretically, the conservation equations describing the main flow field are combined with equations describing droplet behaviour and the set is treated by the time-marching method. Comparisons are carried out with the experimental results presented in the earlier parts of the paper and the agreement obtained is good.

When the droplets present in the steam are 0.15 μm in radius at inlet to the cascade, there is considerable secondary nucleation. With droplets of 0.05 μm radius, secondary nucleation is suppressed, but at high pressure ratios, the thermodynamic loss though reduced is not eliminated.
Analytical Study on Torsional Vibration of Circular and Annular Plate
Authors: Wu T X
Published: June 2006

Circular and annular plates are widely used in machinery as basic components. Their torsional vibration behaviour is studied in this article. An analytical model is developed, and the natural frequencies and mode shapes are calculated for the torsional vibration under different boundary conditions. A physical insight is gained into the torsional vibration behaviour of circular and annular plates. Results show that the torsional vibration behaviour of circular and annular plates is different compared with that of circular shafts. Torque moment in annular plates is transmitted via ring layers from the inner ring to the outer ring and vice versa. In addition, the torsional vibration magnitude in terms of angular displacement decreases with increase in radius. This can be explained by the fact that, when vibration energy is transmitted from the inner ring to the outer ring, the circle becomes larger and the energy density becomes lower. It is similar to the situation of a spherical wave propagation from its source. The analytical results are verified using an FEA model. Good agreement is shown between the analytical and FEA models.
Elastic-Plastic Finite-Element Analysis of Repeated, Two-Dimensional Wheel-Rail Rolling Contact under Time-Dependent Load
Authors: Wen Z. F. , Jin X. S.
Published: June 2006

A study was performed using a finite-element model to obtain stresses, strains, and deformations for repeated, two-dimensional rolling contact of a locomotive driving wheel and a rail under time-dependent load. An advanced cyclic plasticity model was used with a commercial finite element code via a material subroutine. The time-dependent load was considered a harmonic variation of the wheel-rail normal contact force. The normal contact pressure was assumed to follow the Hertzian distribution and the tangential force followed the Carter distribution. A wavy profile is formed on the running surface of the rail subjected to the harmonic variation of the normal (vertical) contact force. The developed wavelength of the profile corresponds to the frequency of the normal contact force for the actual train speed. The creepage or rolling-sliding condition plays an important role in the residual strains and deformations, but its influence on the residual stresses is insignificant. The residual stresses at the surface decrease with increasing rolling passes and gradually tend to stabilize. The residual strains and surface displacements increase with increasing rolling cycle, but the increases in residual strain and surface displacement per rolling pass (ratchetting rate) decay. The residual stresses, strains, and deformations near the wave trough of the residual wavy deformation are larger than those near the wave crest. For any given creepage including zero value, when the number of rolling passes increases, the surface depth of the wavy-deformed surface increases but the ratchetting rate decays. The results are useful in investigating the influence of plastic deformation on rail corrugation.
Hybrid Method for Assessing the Performance of Sports Surfaces During Ball Impacts
Authors: Carré M J , James D M , Haake S J
Published: June 2006

Predicting the behaviour of sports surfaces during ball impacts can be extremely complex, especially if both the surface and the ball are made up of combinations of materials that behave non-linearly. This study uses a hybrid approach of experimental measurement and mathematical modelling to predict the performance of sports surfaces in real impact situations. An impact hammer system was first designed and developed, which is capable of accurate field testing and provides data to form model parameters for a variety of sports surfaces (e.g. tennis court, cricket pitch). A mass-spring-damper model of a deformable ball impacting on a rigid surface was then combined with a model of the rigid hammer-surface impact to form a two degre-of-freedom model of a deformable ball impacting on a deformable surface. Model predictions were independently verified using high speed video measurements of cricket ball-pitch impacts, and a good agreement was found. This hybrid approach provides parameters to categorize a surface and predict impact performance.
The Dependence of the Polarity of Solvents on 1,3 : 2,4-Di-O-benzylidene-d-sorbitol Gel
Authors: Yamasaki Seiji , Tsutsumi Hisao
Published: July 2006

1,3 : 2,4-Di-O-benzylidene-d-sorbitol (d-DBS) is known as a chiral oil gelator for a wide variety of organic solvents. The relationship between texture, structure of the gel, and the aggregated structure formed by d-DBS was investigated in various solvents. In the low polar solvents, the gel held a mesh type network structure in which the fiber appeared to be a rope-like helical structure. In the moderately polar solvents, the gel held an isotropic mesophase, but in the polar solvents, a spherulite texture was observed. From the experiments for the critical gel concentration of d-DBS in various solvents, it is assumed that there are three regions that differ in the form of hydrogen bonding, depending upon the polarity of solvents. By IR spectroscopic measurements, we found that, with the increase of solvent polarity, the hydrogen bonding between d-DBS and the solvent became more predominant than the intramolecular hydrogen bonding, and the hydrogen bonding between d-DBS became weaker at the same time. In addition, the intensities of CD spectra in the d-DBS gel decreased according to the increase of the solvent polarity. Here it is considered that textures and structurs observed in the gel are related to the aggregated structure that is mainly formed through hydrogen bonding among d-DBS.
An Equation of State for the Self-Diffusion Coefficient in Lennard–Jones Fluid Derived by Molecular Dynamics Simulations
Authors: Kataoka Yosuke , Fujita Minoru
Published: July 2006

The self-diffusion coefficient in Lennard–Jones fluid was studied by molecular dynamics simulation. Simulations were done at 414 states in the temperature–volume plane. An equation of state for the self-diffusion coefficient was derived by the least-square fitting. The calculated equation of state was in agreement with the experimental results on CO2. Its pressure dependence was also consistent with that in liquid hexane. The liquid structure was analyzed by the excess coordination number, the distributions of the cluster size and the hole volume. The volume dependence of the self-diffusion coefficient in the two-phase region was discussed in terms of the coordination number in the first shell.
Raman Polarizability for Some Totally Symmetric Normal Vibrations of Naphthalene and Maleic Anhydride
Authors: Shimizu Fumio , Nibu Yoshinori , Osaki Tomoe , Shimada Hiroko , Shimada Ryoichi
Published: July 2006

The values of the Raman polarizability of some totally symmetric normal vibrations of naphthalene and maleic anhydride were estimated from the analysis of the polarized Raman spectra observed in single crystal. For the totally symmetric ring vibrations of naphthalene the principal elements of the Raman polarizability in the molecular plane are about isotropic and the principal element perpendicular to the molecular plane has the value almost one-half of the values of the in-plane elements. For the totally symmetric C=O and C=C stretching vibrations of maleic anhydride the Raman polarizability shows quite anisotropic character.
Recent Advances in Aerobic Oxygenation
Authors: Mukaiyama Teruaki , Yamada Tohru
Published: July 2006

Recent advances in the aerobic oxygenations of olefins using transition-metal complex catalysts are reviewed. The main topics focused on are the cobalt(II)-complex-catalyzed oxygenation of olefins, nickel(II)-complex-catalyzed aerobic epoxidation, enantioselective, aerobic epoxidation using chiral manganese(III) complex catalysts, aerobic Baeyer–Villiger oxidation and direct oxygenation of aromatic compounds.
Steric Control of Selectivity for Lanthanoids in Liquid–Liquid Extraction with Tris- and Tetrakis(pyrazol-1-yl)borate–β-Diketon Mixed-Ligand Systems
Authors: Kokusen Hisao , Sohrin Yoshiki , Hasegawa Hiroshi , Kihara Sorin , Matsui Masakazu
Published: July 2006

Mixed-ligand chelate extraction of trivalent lanthanoid ions (M3+) into benzene with poly(pyrazol-1-yl)borate (HnB(pz)4−n; n = 0, 1) and β-diketone was studied. The β-diketones used were dibenzoylmethane (dbm) and dipivaloylmethane (dpm). Lanthanoid ions were extracted as [M{HnB(pz)4−n}2(β-diketone)]. The logarithmic extraction constants (log Kex) of the [HB(pz)3]− systems were 5—6 higher than those of the [B(pz)4]− systems. The highest separability for lanthanide ions was achieved with the [B(pz)4]−– dbm system. These features of log Kex were principally governed by intra- and interligand steric contact.
Photochemistry of μ-Amido-μ-hyperoxo-dicobalt(III) Complexes with Ammine and Polyamine Ligands in Aqueous Solutions: Effects of Ligand and pH
Authors: Shinohara Nobuyoshi , Shibukawa Hirohiko , Shinozaki Kazuteru , Yoshikai Mika
Published: July 2006

Photolyses of μ-amido-μ-hyperoxo-dicobalt(III) complexes, [LCo(NH2,O2−)CoL]4+ (L = 4NH3 (1), en + 2NH3 (2), 2en (3), tren (4)), (tren: 2,2′,2″-triaminotriethylamine, en: ethylenediamine) were investigated. The photolysis of complex 4 in a neutral aqueous solution produced a μ-hydroxo-μ-peroxo-dicobalt(III) complex, [(tren)Co(OH,O22−)Co(tren)]3+, together with a mononuclear cobalt(III) complex, [Co(NH3)(tren)(H2O)]3+. A mononuclear complex and Co2+ were produced in the photolyses of μ-hyperoxo complexes 1 and 2 containing NH3 ligand in neutral aqueous solutions. In acidic media, only mononuclear complex and Co2+ were produced in the photolysis of all μ-hyperoxo complexes examined. Quantum yields of the complexes with NH3 increased with increasing the number of coordinated NH3 (φ = 0.25, 0.11, 0.023, and 0.028 for complexes 1, 2, 3, and 4, respectively, at 365 nm irradiation in neutral region). The quantum yields obtained in acidic solutions were similar in magnitude to those obtained in neutral solutions.
Model Reaction of Self-Condensation of Sulfenic Acids. Kinetic Investigation for the Reaction of Methyl Benzenesulfenate with trans-Decalin-9-sulfenic Acid and 2-Methyl-2-propanesulfenic Acid
Authors: Yoshimura Toshiaki , Hamada Kazuhiro , Yamazaki Satoru , Shimasaki Choichiro , Ono Shin , Tsukurimichi Eiichi
Published: July 2006

Reaction of 2-methyl-2-propanesulfenic acid (1) with methyl arenesulfenates (2) gave S-aryl 2-methyl-2-propanethiosulfinates quantitatively, and kinetic investigation was carried out. Second-order rate dependence (first-order in methyl benzenesulfenate (2a) and first-order in the sulfenic acid (1)) was observed, and a small activation enthalpy (ΔH‡ = 28 kJ mol−1) and a large negative activation entropy (ΔS‡ = −130 J K−1 mol−1) were obtained. Kinetics for the reaction of trans-decalin-9-sulfenic acid (3) with the sulfenates 2 under acidic conditions in methanol–water gave the observation of the second-order dependence, a small activation enthalpy (ΔH‡ = 30.5 kJ mol−1), a large negative activation entropy (ΔS‡ = −140 J K−1 mol−1), a large negative Hammett ρ-value (ρ = −1.39) and no solvent isotope effect (kMeOH/kMeOD = 1.10—1.14 in the range of 15.64—29.98 °C). Kinetics for acidic hydrolysis of the sulfenate 2 under the same conditions afforded the similar activation parameters (ΔH‡ = 40.7 kJ mol−1, ΔS‡ = −200 J K−1 mol−1 at [H2O] = 0.80 × 10−3mol dm−3) and a larger negative Hammett ρ-value (ρ = −2.22) than that for the reaction of the sulfenic acid 3 with the sulfenate 2. From these results, structures of the transition state for both the self-condensation of sulfenic acid and the hydrolysis of the sulfenate ester 2 were discussed. The reaction of sulfenate esters 2 with stable sulfenic acids is a good model for studying the self-condensation of sulfenic acids.
Physalins Possessing an Endoperoxy Structure from Physalis alkekengi var. francheti. Structural Revision of Physalin K
Authors: Makino Bunsho , Kawai Masao , Iwata Yasushi , Yamamura Hatsuo , Butsugan Yasuo , Ogawa Kiyoshi , Hayashi Mitsuo
Published: July 2006

Physalin K was isolated from Physalis alkekengi var. francheti. Spectroscopic studies and chemical correlations, however, revealed that the reported structure of physalin K at the AB ring moiety, namely, 4α,5α-epoxy-6α-hydroxy-2-en-1-one, should be revised to 2α,5α-epidioxy-6β-hydroxy-3-en-1-one. A new physalin, named physalin Q, was also isolated and identified as the 2β,5β-epidioxy diastereomer of physalin K.
Facile Synthesis of Thiolariat Ethers or Crown Ethers Containing a Mercapto Group as a Side Arm
Authors: Nabeshima Tatsuya , Tsukada Naoko , Haruyama Tsutomu , Yano Yumihiko
Published: July 2006

Cyclization reaction of S-substituted thioglycerol and oligoethylene glycol ditosylate gave thiolariat ethers in moderate yields. Mercaptomethyl crown ethers were obtained easily from benzylthiomethyl crown ethers by Na in liq. NH3–BuOH.
Observation of the Adsorption of Cytochrome c and Glucose Oxidase onto an Amphiphilic Monolayer at an Air/Water Interface by the Reflection Spectroscopy of Visible Radiation
Authors: Ohnishi Michihiro , Ishimoto Coe , Seto Jun’etsu
Published: July 2006

The adsorption of two kinds of chromoproteins, cytochrome c and glucose oxidase, was observed at an air/water interface by reflection spectroscopy using optical fibers. The relation between the adsorption of cytochrome c onto an amphiphilic monolayer and the deposition of the monolayer with cytochrome c by the Langmuir–Blodgett (LB) technique was clarified. It was found out that a good Y-type LB film, with a transfer ratio of 0.9—1.0, was obtained when the adsorbed area of cytochrome c was less than about 84% of the maximum average coverage. The reflection spectrum of glucose oxidase, not as such, but stained with coomassie brilliant blue (CBB), could be successfully observed. Since CBB is applicable to almost any protein, the reflection spectroscopy of almost any protein, not only chromoproteins, is possible.
Triarylcarbenium Salts Highly Reducible by Primary Alcohols
Authors: Wada Masanori , Mishima Hisashi , Watanabe Tetsuya , Natsume Satoko , Konishi Hideki , Kirishima Katsuhiko , Hayase Shuichi , Erabi Tatsuo
Published: July 2006

A series of triarylmethanols bearing o-methoxyl groups (1a: [2,6-(MeO)2C6H3]3COH, 1b: (2-MeOC6H4)[2,6-(MeO)2C6H3]2COH, 1c: Ph[2,6-(MeO)2C6H3]2COH, 1d: [2,5-(MeO)2C6H3]3COH, 1e: Ph2[2,6-(MeO)2C6H3]COH) were prepared. Corresponding carbenium salts, [Ar3C]X 2a—c, were isolated by short-period treatments of Ar3COH 1a—c with a slight excess of acid in some bulky alcohols, such as 2-propanol or 2-methyl-1-propanol. The high basicity of 1a—c was explained by through-space interactions of a pair of 2p electrons of an o-methoxyl oxygen with an empty 2p orbital of the resulting carbenium carbon. In ethanol, 1-butanol or 3-methyl-1-butanol, 1c, as well as 2c, was reduced under very mild conditions to triarylmethane, Ar3C–H 3c, and in other bulkier alcohols it was reduced under more forcing conditions. The formations of aldehyde or ketone, the by-product, were confirmed in some cases. Compounds 1a,b,d,e, as well as 2a,b, reacted in analogous manners under more forcing conditions. The reaction rates in several alcohols increased in the order 2a < 2b < 2c, and the reaction rates of alcohol for 2c decreased in the order ethanol > 3-methyl-1-butanol > 1-butanol > 2-propanol > methanol > 2-butanol > 2-methyl-1-propanol. Compounds 2b,c were also reduced in tetrahydrofuran, and formed xanthene derivatives in dimethyl sulfoxide or in water.
Nucleophile-Induced Ring Enlargement of 1-(1-Iodoalkyl)silacyclobutane and 1-(1,2-Epoxyalkyl)silacyclobutane into Silacyclopentane. Application to the Syntheses of 1,4-Diol, 4-Alken-1-ol, and 1,4,5-Triol
Authors: Matsumoto Kozo , Takeyama Yoshihiro , Miura Katsukiyo , Oshima Koichiro , Utimoto Kiitiro
Published: July 2006

Two methods for ring enlargement of silacyclobutane into silacyclopentane have been described. (1) Treatment of 1-(1-iodoalkyl)silacyclobutane with t-BuOK or AgOAc provided 2-alkyl-1-silacyclopentanes which were easily converted into 1,4-diols by oxidative cleavage of carbon–silicon bond. (2) An addition of i-PrOLi to 1-[(Z)-1,2-epoxyhexyl]-1-methylsilacyclobutane gave erythro-2-(1-hydroxypentyl)-1-isopropoxy-1-methylsilacyclopentane, which was converted into (Z)-4-nonen-1-ol, (E)-4-nonen-1-ol, or 1,4,5-nonanetriol.
Sequential Electron Transfer Leading to Long-Lived Charge Separated State in a Porphyrin–Oxochlorin–Pyromellitdimide Triad
Authors: Osuka Atsuhiro , Marumo Shinji , Maruyama Kazuhiro , Mataga Noboru , Tanaka Yoshinori , Taniguchi Seiji , Okada Tadashi , Yamazaki Iwao , Nishimura Yoshinobu
Published: July 2006

The synthesis and excited-state dynamics are described for fixed-distance porphyrin–oxochlorin–pyromellitdimide triads (P–C–Im) and related reference compounds. In zinc-oxochlorin–pyromellitdimide (ZnP–Im), the 1(ZnC)* is quenched by the attached Im through intramolecular charge separation (CS) in benzene, THF, and DMF, while the 1(H2C)* in the corresponding free base is not significantly quenched by the Im even in polar DMF. In the steady-state fluorescence emission spectra, only the emission from the 1(C)* is commonly observed, indicating an efficient intramolecular singlet–singlet excitation energy transfer from P to C. Of these, the fluorescence intensities of the 1(H2C)* in ZnP–H2C and ZnP–H2C–Im are significantly reduced in polar DMF solution and this is attributed to the intramolecular CS that gives (ZnP)+–(H2C)−–Im and (ZnP)+–(H2C)−, respectively. The (ZnP)+–(H2C)−–Im ion pair is clearly shown, by picosecond absorption spectroscopy, to be converted into a secondary, longer-lived charge separated state (ZnP)+–H2C–(Im)− via charge-shift reaction in competition with wasteful charge recombination to the ground state. The (ZnP)+–H2C–(Im)− state is formed in 0.09 quantum yield from ZnP–1(H2C)*–Im and has a lifetime of 0.24 μs in DMF.
Ring Enlargement of α-Ethylidenecycloalkanones to β-Alkylidenecycloalkanones Induced by Trimethylstannyllithium/Aldehyde Equivalents/Lewis Acids
Authors: Fujiwara Jun , Tokuyasu Jin , Sato Tadashi
Published: July 2006

α-Ethylidenecycloalkanones underwent a ring enlargement to β-alkylidenecycloalkanones upon a treatment with trimethylstannyllithium/aldehyde equivalents/Lewis acids with high stereoselectivity.
A New Approach to dl-Cannabichromene
Authors: Yamaguchi Seiji , Shouji Noriaki , Kuroda Kazuyoshi
Published: July 2006

Natural dl-cannabichromene was synthesized in 6 steps from methyl 5-methoxy-2-methyl-7-pentyl-2H-chromen-2-acetate prepared by the cyclization of 2-hydroxy-6-methoxy-4-pentylbenzaldehyde with dimethyl isopropylidenemalonate.
Oxidative Generation of α-Radicals of Carbonyl Compounds from the α-Stannyl Derivatives and Their Reactions with Electron-Rich Olefins
Authors: Kohno Yasushi , Narasaka Koichi
Published: July 2006

The oxidation of α-tributylstannyl alkanoates with tetrabutylammonium hexanitratocerate(IV) generates α-radicals of the alkanoates by eliminating the stannylium ion. The thus-formed radicals react with various electron-rich olefinic compounds, such as silyl enol ethers, giving addition products in good yield. This method formally achieves selective cross coupling between alkanoates and ketones.
Preparation of S-Protected Cysteine-Containing Peptide Thioester and Its Use for the Synthesis of the Barnase-Like Domain in DNA-Directed RNA Polymerase II of Saccharomyces cerevisiae
Authors: Hojo Hironobu , Yoshimura Shoko , Go Mitiko , Aimoto Saburo
Published: July 2006

The Barnase-like Domain in DNA-Directed RNA Polymerase II of Saccharomyces cerevisiae containing three cysteine residues was synthesized by a thioester method. A partially-protected cysteine-containing peptide thioester was prepared via a peptide obtained by a solid-phase method using 3-nitro-2-pyridinesulfenyl amino acid derivatives. Four peptide segments covering 112 amino acid residues of the barnase-like domain were condensed from the C-terminal to the N-terminal one by one in the presence of silver ions and N-hydroxysuccinimide to give a full sequence peptide. RNase activity of the synthetic domain could not be detected because of its extreme low solubility in the neutral buffer.
Thermal Rearrangement of N-Alkyl-, and N-Aryl-(2,2-dihalo-1-phenylcyclopropyl)methyleneamines to 1-Alkyl-, and 1-Aryl-2 (or 3)-halo-4-phenylpyrroles
Authors: Kagabu Shinzo , Tsuji Hideaki , Kawai Itsumi , Ozeki Hitomi
Published: July 2006

The thermolysis of N-t-alkyl-, and N-aryl-(2,2-dichlorocyclopropyl)methyleneamines yielded directly 1-t-alkyl, and 1-aryl-3-chloropyrroles as the major products along with a slight amount of the 2-chloro isomers. The transformation to the 3-chloropyrroles was enhanced in polar solvents. But basic additives directed the thermal rearrangement into the 1,2-bond cleavage of the cyclopropane ring, leading to the 2-chloropyrroles. On the other hand, (difluorocyclopropyl)methyleneamines were pyrolyzed exclusively to 3-fluoropyrroles under 1,3-bond cleavage. The ionic mechanism involving a heterolytic dissociation of chlorine atom under 1,3-bond scission of the cyclopropane ring is proposed for the rearrangement to 3-chloropyrroles, while a homolytic cleavage pathway is proposed for 3-fluoropyrroles. The present thermolysis supplies a unique preparative tool for 2-, and 3-halo-4-phenylpyrrole derivatives.
Stereoselective Organic Synthesis via Dynamic Kinetic Resolution
Authors: Noyori Ryoji , Tokunaga Makoto , Kitamura Masato
Published: July 2006

Asymmetric catalysts, either chemical or biological, effect the reactions of enantiomeric substrates at unequal rates, allowing for the kinetic resolution of racemates. The asymmetric reaction of chirally labile compounds capable of undergoing in situ racemization can, in principle, afford a single stereoisomer in 100% ee and in 100% yield. The second-order reaction provides a powerful tool for the stereoselective synthesis of chiral compounds, as exemplified by, among others, the biochemical hydrolysis of hydantoins or oxazolinones and microbial reductions or BINAP–Ru(II) catalyzed hydrogenation of certain α-substituted β-keto esters. Such transformations are characterized by the presence of parallel reactions interrelated by the stereoinversion of the enantiomeric substrates. The efficiency is decisively affected by the kinetic parameters, particularly the relative rates of the stereoinversion and reaction as well as the intrinsic stereochemical parameters of the catalyst and substrate. Such stereoselective reactions via dynamic kinetic resolution are expressed mathematically and the stereochemical profiles are displayed graphically. The validity of this basic approach has been verified by the correlation to the experimental results.
Synthesis of Artificial HMG-CoA Reductase Inhibitors Based on the Olefination Strategy
Authors: Hiyama Tamejiro , Minami Tatsuya , Takahashi Kyoko
Published: July 2006

Synthetic methods were studied for optically active 6-oxo-3,5-isopropylidenedioxyhexanoate esters (4), which could be used as a key precursor of various kinds of artificial analogs of 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase inhibitors. An enantiomer (+)-4 was prepared by asymmetric reduction of β,δ-diketo esters derived from the Taber’s alcohol or l-tartrate followed by a series of chemical transformations, and the desired enantiomer (−)-4 was prepared by the same asymmetric reduction starting from d-tartrate. The key intermediate (−)-4 was finally converted into a highly potent HMG-CoA reductase inhibitor, NK-104.
Beckmann Rearrangement of Oximes Catalyzed with Tetrabutylammonium Perrhenate and Trifluoromethanesulfonic Acid
Authors: Kusama Hiroyuki , Yamashita Yuko , Narasaka Koichi
Published: July 2006

The Beckmann rearrangement of oximes is catalyzed by a combined use of tetrabutylammonium perrhenate (Bu4NReO4) and trifluoromethanesulfonic acid in nitromethane under azeotropic conditions, giving amides in high yield. By employing this catalytic system, amides can be prepared directly from ketones and hydroxylamine hydrochloride.