bluuebunny/crossref_metadata_2025 huggingface dataset:
Homocysteine, antiphospholipid antibodies and risk of thrombosis in patients with systemic lupus erythematosus
Authors: Martínez-Berriotxoa A , Ruiz-Irastorza G , Egurbide M-V , Rueda M , Aguirre C
Published: December 2004

Cardiovascular disease is a major cause of morbidity and mortality in patients with systemic lupus erythematosus (SLE). Antiphospholipid syndrome (APS) is one of the most important causes of thrombosis in SLE. In addition, an association between hyperhomocysteinemia and increased cardiovascular risk has also been reported. Our aim is to analyse the association of thrombosis with plasma total homocysteine (ptHcy), antiphospholipid antibodies (aPL) and other vascular risk factors in SLE patients. Fasting plasma levels of ptHcy, vitamin B12, folate, total cholesterol and creatinine were measured in 117 SLE patients. Clinical and immunological data were obtained from our prospective computerized database. aPL-positivity was defined according to Sapporo criteria. There was no association between aPL and ptHcy. ptHcy was higher in patients with arterial (median 13.02 versus 10.16 mmol/L, P = 0.010) but not venous thrombosis. In the subgroup analysis, this association was only seen in aPL-negative patients. In logistic regression, aPL (OR 6.60, 95% CI 1.86-23.34) and ptHcy (OR 1.10, 95% CI 1.01-1.19) were independently associated with arterial thrombosis. However, when hypertension, smoking and plasma total cholesterol were added to the model, only aPL (OR 7.38, 95% CI 2.02-26.91) and hypertension (OR 7.70, 95% CI 2.33-25.39), but not ptHcy, remained independently related to arterial events. aPL was the only variable independently related to venous thrombosis (OR 7.68, 95% CI 1.60-36.86). ptHcy concentrations are higher in SLE patients with arterial thrombosis. No interaction between homocysteine and aPL was found. Raised ptHcy may be a marker of increased vascular risk in aPL-negative SLE patients. The role of homocysteine as a marker of vascular risk may depend on the presence of traditional risk factors, although a modest intrinsic effect cannot be entirely excluded.
Systemic lupus erythematosus in southern Spain: a comparative clinical and genetic study between Caucasian and Gypsy patients
Authors: Ramal L M , López-Nevot M A , Sabio J M , Jáimez L , Paco L , Sánchez J , de Ramón E , Fernández-Nebro A , Ortego N , Ruiz-Cantero A , Rivera F , Martín J , Jiménez-Alonso J ,   Grupo Lupus Virgen de las Nieves
Published: December 2004

We evaluated the influence of the hereditary make-up on the development of systemic lupus erythematosus (SLE) in two ethnic groups [Gypsy and white Caucasian Mediterranean (WCM) populations], living in the same geographic area. We compared 81 WCM and 25 Gypsy patients with SLE. The control group consisted of 185 healthy unrelated individuals, 105 WC and 80 Gypsies. In the Gypsy population, the onset of SLE occurred at earlier ages than in the other ethnic group (25.9 versus 32.0 years, P = 0.02), and showed lower SLEDAI peak values (4.9 versus 7.0, P = 0.016). The frequency of joint, kidney, gastrointestinal and eye involvement was significantly lower in Gypsy patients. In contrast, SLE-associated antiphospholipid syndrome, thrombosis and livedo reticularis were more frequent in Gypsies than in the majority ethnic group (WCM). In WCM patients, DRB1*1303- DQB1*0301 haplotype was associated with SLE ( P = 0.001, Pc = 0.038). We found SLE to be associated with DR5 ( P = 0.006, Pc = 0.05) in the Gypsy population as well as a protective effect of DPB1*0401 when DR5 was not present ( P = 0.008, Pc = 0.032). In conclusion, we found some clinical differences between WCM and Gypsy patients with SLE. Furthermore, HLA associations between HLA-DRB1-DQB1 and SLE were different for Gypsy people.
Toxic epidermal necrolysis-like acute cutaneous lupus erythematosus and the spectrum of the acute syndrome of apoptotic pan-epidermolysis (ASAP): a case report, concept review and proposal for new classification of lupus erythematosus vesiculobullous skin lesions
Authors: Ting W , Stone M S , Racila D , Scofield R H , Sontheimer R D
Published: December 2004

The acute clinical syndrome of toxic epidermal necrolysis (TEN) is currently thought to be a distinct clinical-pathological entity typically resulting from drug hypersensitivity. We describe an adult woman who experienced a fulminate pattern of apoptotic epidermal cell injury following tanning bed exposure while taking naproxen that resulted in a clinical presentation having combined features of drug-induced TEN and an infrequently recognized form of bullous cutaneous lupus erythematosus (LE). This case calls attention to the fact that TEN-like injury can occasionally be seen in settings other than drug hypersensitivity (e.g., LE, acute graft versus host disease) and illustrates the need for a unifying concept in this area. We therefore propose the term ‘Acute Syndrome of Apoptotic Pan-Epidermolysis (ASAP)’ to designate a clinical syndrome that is characterized by life-threatening acute and massive cleavage of the epidermis resulting from hyperacute apoptotic injury of the epidermis. We also review vesiculobullous skin disorders that can be encountered in LE patients and suggest a new classification scheme for such lesions.
Intestinal pseudo-obstruction and ureterohydronephrosis as the presenting manifestations of relapse in a lupus patient
Authors: Alexopoulou A , Andrianakos A , Dourakis S P
Published: December 2004

Intestinal pseudo-obstruction (IPO) is a rare complication of systemic lupus erythematosus (SLE). We present a 32-year old female with SLE for seven years. She was admitted with profound fatigue, frequent vomiting, colicky abdominal pain, diarrhoea and intermittent dysuria for the past 12 months. Imaging studies revealed dilated small and large bowel loops with thickened intestinal wall and multiple fluid levels. Urinary tract involvement was also demonstrated. The patient responded well to immunosuppressive treatment. IPO in the context of SLE has been described only in anecdotal case reports. Half of the cases developed this complication during the course of lupus as in the present case. Concomitant ureterohydronephrosis was present in approximately two-thirds of the cases. Early recognition of the syndrome is necessary for the institution of the appropriate medical treatment and prevention of inappropriate surgical intervention.
Imatinib-Induced Regression of AIDS-Related Kaposi's Sarcoma
Authors: Koon Henry B. , Bubley Glenn J. , Pantanowitz Liron , Masiello David , Smith Brad , Crosby Katherine , Proper JoAnn , Weeden Will , Miller Thomas E. , Chatis Pamela , Egorin Merrill J. , Tahan Steven R. , Dezube Bruce J.
Published: December 2004

Purpose

Activation of the platelet-derived growth factor (PDGF) and c-kit receptors has been proposed as important in mediating the growth of AIDS-related Kaposi's sarcoma (KS). We investigated the response of KS to the PDGF receptor (PDGFR)/c-kit inhibitor, imatinib mesylate, and investigated the effect of this therapy on critical signal transduction intermediates.

Patients and Methods

Ten male patients with AIDS-related cutaneous KS, which progressed despite chemotherapy and/or highly active antiretroviral therapy, received imatinib mesylate administered orally, 300 mg twice daily. Clinical response was determined by serial tumor measurements. To determine biologic and histologic response, skin lesion biopsies were obtained at baseline and following 4 weeks of therapy.

Results

Five of 10 participants had a partial response by tumor measurements. Biopsies after 4 weeks of therapy demonstrated histologic regression in four of six patients. Four patients' tumor biopsies were assessable for immunohistochemistry end points pre- and post-therapy. These demonstrated inhibition of PDGFR and its downstream effector, extracellular receptor kinase, which is a member of the mitogen-activated protein kinase family. The most common adverse event was diarrhea, which led to dose reduction in six patients.

Conclusion

Imatinib mesylate administered orally twice daily for AIDS-related KS results in clinical and histologic regression of cutaneous KS lesions within 4 weeks. These promising results demonstrate that inhibition of the c-kit and/or PDGF receptors may represent an effective strategy for treating KS.
Long-Term Survival Rates of Patients With Prostate Cancer in the Prostate-Specific Antigen Screening Era: Population-Based Estimates for the Year 2000 by Period Analysis
Authors: Brenner Hermann , Arndt Volker
Published: December 2004

Purpose

In the era of widespread prostate specific antigen (PSA) screening, a large proportion of older men have to live with a diagnosis of prostate cancer. In this study, we applied a new method for up-to-date analysis of long-term survival to evaluate if and to what extent these patients still have any excess mortality compared to the general population.

Methods

Five- and 10-year absolute and relative survival rates for the year 2000 were derived from the 1973 to 2000 database of the Surveillance, Epidemiology and End Results Program using the recently introduced period analysis methodology.

Results

Overall, 5- and 10-year relative survival rates were approximately 99% and 95%; that is, excess mortality compared with the general population was as low as 1% and 5% within 5 and 10 years following diagnosis, respectively. Two-thirds of patients were diagnosed with well or moderately differentiated localized/regional prostate cancer, and among these patients, 5- and 10-year relative survival rates were above 100% (indicating the lack of any excess mortality) at all ages.

Conclusion

While the value of PSA screening for lowering mortality due to prostate cancer remains to be shown by randomized clinical trials, the majority of patients diagnosed with prostate cancer in the PSA screening era do not have excess mortality compared to the general population under current patterns of medical care. This information may be important for both clinical management of, and for patients' coping with, the disease.
Distinct functions of condensin I and II in mitotic chromosome assembly
Authors: Hirota Toru , Gerlich Daniel , Koch Birgit , Ellenberg Jan , Peters Jan-Michael
Published: December 2004

Condensin is a protein complex associated with mitotic chromosomes that has been implicated in chromosome condensation. In vertebrates, two types of condensin complexes have recently been identified, called condensin I and II. Here, we show that in mammalian cells condensin II associates with chromatin in prophase, in contrast to condensin I which is cytoplasmic and can thus interact with chromosomes only after nuclear envelope breakdown. RNA interference experiments in conjunction with imaging of live and fixed cells revealed that condensin II is required for chromosome condensation in early prophase, whereas condensin I appears to be dispensable at this stage. By contrast, condensin I is required for the complete dissociation of cohesin from chromosome arms, for chromosome shortening and for normal timing of progression through prometaphase and metaphase, whereas normal condensin II levels are dispensable for these processes. After depletion of both condensin complexes, the onset of chromosome condensation is delayed until the end of prophase, but is then initiated rapidly before nuclear envelope breakdown. These results reveal that condensin II and I associate with chromosomes sequentially and have distinct functions in mitotic chromosome assembly.
Model testing the two-phase scavenging system in a two-stroke petrol engine
Authors: Čudina M
Published: December 2004

Due to an inadequate scavenging process two-stroke petrol engines suffer from substantial fuel-specific consumption, as well as from considerable emissions of toxic components in exhaust gases. This paper describes the model testing and evaluation of a new scavenging system in a small two-stroke petrol engine with internal working mixture preparation. The scavenging process is performed by two different gas media in two successive phases and is more sophisticated and effective than the conventional single-phase (Schnürle) principle. Using the similarity principle and dimensional analysis, a new mathematical model was developed for evaluation of the effectiveness of the scavenging systems. This makes it possible to establish relationships between the most important parameters of the model engine and of the real engine, which are independent of the dimensional parameters. The effectiveness of the scavenging systems was defined by means of qualitative scavenging efficiency. A special testing device for the model engine has been developed and a liquid working media (instead of gaseous) is used. A qualitative as well as a quantitative evaluation of the predicted values and a simulation of the working medium exchange process at different working conditions is possible. A visual observation of the slowed-down scavenging process in a transparent model cylinder was also made. The mathematical model can be applied to any scavenging system of two-stroke engines or to similar periodic events in the process technique.
Modelling of loss mechanisms in a pushing metal V-belt continuously variable transmission. Part 3: Belt slip losses
Authors: Akehurst S , Vaughan N D , Parker D A , Simner D
Published: December 2004

The power transmission efficiency of continuously variable transmissions (CVTs) based on the pushing metal belt is acknowledged to be lower than that of discrete ratio alternatives. This tends to negate the potential fuel economy benefits that are obtained by improved engine/load matching with a CVT. This series of three papers details an investigation into the loss mechanisms that occur within the belt drive as a first step to obtaining improvements in efficiency.

This third paper follows on from two previous papers in which an analysis was performed modelling the torque losses that occur due to relative motion between the bands and segments of the belt, and between the pulleys and the belt due to pulley deflection effects. It describes additional experimental work, measuring the belt-slip speed tangentially about both of the pulleys in the variator. Additional loss models are proposed beyond those discussed in Parts 1 and 2 to describe the belt-slip phenomena, based on existing theory proposed by others. The analysis produced in this paper is validated against a range of experimental data and additionally through its close interaction with the torque-loss and torque-force distribution models proposed in Parts 1 and 2. The work takes into account new findings in other research and changes in the design of the current metal V-belt.
Modelling of loss mechanisms in a pushing metal V-belt continuously variable transmission. Part 1: Torque losses due to band friction
Authors: Akehurst S , Vaughan N D , Parker D A , Simner D
Published: December 2004

The power transmission efficiency of continuously variable transmissions (CVTs) based on the pushing metal belt is acknowledged to be lower than that of discrete ratio alternatives. This tends to negate the potential fuel economy benefits that are obtained by improved engine/load matching with a CVT. This series of three papers details an investigation into the loss mechanisms that occur within the belt drive as a first step to obtaining improvements in efficiency.

Experimental work has been undertaken to investigate the no-load and low-load torque losses associated with a pushing metal V-belt CVT. This first paper describes a new analysis of the principal torque losses occurring in the metal belt CVT due to relative motion occurring between the belt segments and bands. The work takes into account new findings in other research and changes in the design of the metal V-belt. The torque loss model proposed in this paper is supported by experimental data from several different test procedures. A number of additional torque loss mechanisms, due to pulley deflections, are described in Part 2 of the series. The findings from this current paper support an analysis of belt-slip losses, which is described in detail in Part 3.
Modelling of loss mechanisms in a pushing metal V-belt continuously variable transmission: Part 2: Pulley deflection losses and total torque loss validation
Authors: Akehurst S , Vaughan N D , Parker D A , Simner D
Published: December 2004

The power transmission efficiency of continuously variable transmissions (CVTs) based on the pushing metal belt is acknowledged to be lower than that of discrete ratio alternatives. This tends to negate the potential fuel economy benefits that are obtained by improved engine/load matching with a CVT. This series of three papers details an investigation into the loss mechanisms that occur within the belt drive as a first step to obtaining improvements in efficiency.

This second part follows on from an initial paper in which an analysis was performed of the losses that occur due to relative motion between the bands and segments of the belt. Additional experimental work has been performed indicating that a significant deflection occurs in the pulleys of the variator. Further torque-loss models are proposed in addition to that discussed in Part 1, representing a smaller but still significant torque loss associated with the belt. The work takes into account new findings in other research and changes in the design of the metal V-belt. The third paper in this series develops a number of models to predict belt-slip losses in the variator system, based on force distribution models developed in Part 1.
Study on the injection process of a direct-injection diesel engine fuelled with dimethyl ether
Authors: Zhang G D , Liu H , Xia X X , Yang Q L
Published: December 2004

The injection process of dimethyl ether (DME) was tested on a naturally aspirated, direct- injection (DI) diesel engine with a pump-line-nozzle fuel system. In order to eliminate vapour leakage, DME was pressurized into the injection pump by nitrogen. In view of its low calorific value and liquid density, the pump plunger diameter and nozzle orifice area were enlarged to achieve the rated power. As DME is easy to atomize and evaporate, the nozzle opening pressure was lowered. The study demonstrates that the injection delay with DME is much longer than that with diesel fuel, due to the lower sound velocity in DME liquid, resulting from its higher compressibility and lower density. When a diesel engine operates on DME instead of diesel fuel, the advance angle of fuel supply should be increased. The fluctuations of line pressure, nozzle needle lift, opening time, and closing time for DME are larger than those for diesel fuel.
Performance evaluation and case studies of microturbines fuelled with natural gas and diesel
Authors: Gomes E E B , do Nascimento M A R , Lora E E S , Pilidis P , Haslam A
Published: December 2004

The high reliability and simple design of microturbines make them an attractive prime mover in the generation and distribution of electricity in the low capacity range. This paper gives an overview of microturbines in the Brazilian environment and provides a performance assessment and an economic analysis of these machines fuelled by natural gas and diesel and also an indication of their emission levels. This work was based on data that were obtained from experimental tests on microturbines operating at full and part load. The performance assessment indicated that it is possible to obtain up to 27 per cent microturbine efficiency at full load under local conditions. The nitrogen oxides (NOx) and carbon monoxide (CO) emissions level of the machines tested are less than 7 ppmv@15%O2 at full load when natural gas is the fuel. The units are therefore clean enough to be sited among residential and commercial establishments. The results of the economic analysis show that with the natural gas microturbine used in cogeneration, it is possible to achieve a payback time on capital equipment of less than 4 years. The return on the investment has improved with the favourable pricing policies of some of the natural gas distribution companies and with the rise in electricity prices in Brazil.
Optimization techniques for designing an inward flow radial turbine rotor
Authors: Ebaid M S Y , Al-Hamdan Q Z
Published: December 2004

The choice of the principal dimensions of a turbine rotor for a given set of inlet design specifications can be found by solving aerodynamic equations. An analytical method is indeed difficult and can be very time consuming, especially if the complete procedure has to be repeated for different cases. In view of this, numerical optimization techniques can be a useful tool to problems involving a large number of variables. However, turbines commonly operate at high temperature and at high speeds, therefore the design process is an interactive one between the aerodynamic requirements and the mechanical, thermal limitations. This paper describes the complete design work of a turbine rotor based on using a nonlinear optimization technique to calculate the optimum principal dimensions of the rotor including optimum number of blades. Also, a prescribed mean stream velocity approach is used to determine the optimum axial length and the flow passage. For mechanical consideration, structure and thermal stresses and modal (vibration) analyses were carried out to satisfy design requirements.
Prediction of the thermal performance of solar air heaters by Internet-based mathematical simulation
Authors: Bashria A A , Adam N M , Sapuan S M , Daud M , Omar H , Megat H M , Abas F
Published: December 2004

This paper presents an internet-based mathematical simulation for predicting the thermal performance of solar air collectors to collect energy used for drying various products. The solution procedure was performed for a flat plate collector and a V-groove absorber. The thermal performance was determined over a wide range of operating conditions, but in the same configuration for the two types of solar collector. The V-groove absorber was found to be more efficient than the flat plate collector. The optimum operating conditions were determined. Comparison between predicted and experimental results indicates that the proposed mathematical model can be used for estimating the thermal performance of solar air heaters with reasonable accuracy.
Effect of diffuser vane height and position on the performance of a centrifugal compressor
Authors: Issac J. M. , Sitaram N , Govardhan M
Published: December 2004

The present paper reports experimental investigations on the effect of diffuser vane height and position on the performance of a low-speed centrifugal compressor. The diffuser vane height is systematically varied from 0.2 to 0.9 times the diffuser width. In addition, the effect of vane position is examined by fixing the partial vanes to the hub, shroud, or hub and shroud. The compressor performance is determined with these vanes in the vane and low solidity vane diffuser configurations. It is found that there is an optimum height for the diffuser vane height. In the present investigation, it is found to be 0.3 times the diffuser width. The effect of position of the partial vanes on the hub or shroud on the compressor performance is found to be negligible. However, when partial vanes are fixed on the hub and shroud staggered at half spacing, the compressor performance is improved substantially.
Unsteady one-dimensional model for a bed combustion of solid fuels
Authors: Yang Won , Ryu Changkook , Choi Sangmin
Published: December 2004

A transient one-dimensional combustion model of a solid fuel bed that can be applied to various types of combustors employing the solid bed is suggested. Configuration of solid beds can be characterized by combinations of solid and gas flow directions, ignition methods, and dominant reactions. These features can be reflected numerically to the boundary and initial conditions of the model, while the governing mechanism in each type of bed is similar. The mechanism is expressed as forms of conservation equations for the solid and the gas phase. Solid-gas reactions, gaseous reactions, heat transfer, geometrical changes of the particles, and physical properties are modelled and reflected to each term of the governing equations. Simulation results are shown for two cases: a packed bed combustor and an iron ore sintering bed. Two cases have distinctively different bed configurations and ignition methods. The propagation rates of the combustion zone are quantitatively discussed in terms of the flame propagation speed. Future development of the model is discussed for possible application to more complicated simulation cases.
Statistical analysis of wind energy potential on the basis of the Weibull and Rayleigh distributions for Agin-Elazig, Turkey
Authors: Akpinar E. K. , Akpinar S
Published: December 2004

In the present study, the wind energy potential of the region is statistically analysed on the basis of 5 year measured hourly time series wind speed data. The probability density distributions are derived from time series data, and distributional parameters are identified. Two probability density functions are fitted to the measured probability distributions on a yearly basis. The wind energy potential of the location is studied on the basis of the Weibull and the Rayleigh models.
Maintenance strategy for a coal-based steam power plant equipment: A graph theoretic approach
Authors: Mohan M , Gandhi O. P. , Agrawal V. P.
Published: December 2004

Maintenance cost and downtime losses of a steam power plant can be reduced by adopting a proper mix of maintenance strategies that ensure its reliable availability. The type of maintenance for different equipment in a power plant is decided as per its importance in terms of attributes such as maintenance efforts, loss of production, safety/reliability and efficiency. In the worst situation, failure of hypothetical equipment would affect all these attributes and would thus have maximum criticality. In general, the failure of equipment would not affect all the attributes and therefore its criticality will have some intermediate value. The level of criticality would decide the importance of the power plant equipment and choice of appropriate maintenance strategy. The procedures reported in literature are empirical co-relations to combine major attributes into a single index and have the limitation of using a number of attributes simultaneously. Using Graph theory and the Matrix method, a systems-based mathematical model has been developed for determining the maintenance criticality index of equipment of a coal-based steam power plant. The proposed model does not have any limitation either regarding the number of attributes or the interactions among these. Being a mathematical model, it is also not subjective. Plant equipment is categorized into four groups as per the ranking of its maintenance criticality index and a suitable maintenance strategy is recommended for each group. A step-by-step procedure for finding the criticality index has also been proposed in the paper. Using this procedure, an appropriate maintenance strategy for any other type of power plant/industry can also be recommended.
Choosing and evaluating sites for tidal current development
Authors: Bryden I , Melville G. T.
Published: December 2004

Tidal energy has been used since Roman times, although the use of tidal currents as a possible industrial energy source is a more modern concept. Unlike wind power, however, there is still no consensus on the most appropriate technology for resource exploitation. Similarities with wind power can cause errors of interpretation, especially when attempting to assess resource potential. The energy availability estimates that have been produced have, until now, only taken account of the apparent current flow speeds before the extraction of energy. As demonstrated in this paper, this may not be appropriate, especially for large energy extraction rates, which alter the underlying hydraulic nature of the flow environment. In a simple hypothetical channel linking two infinite oceans, a maximum extraction of 10 per cent of the apparent raw kinetic flux would appear to be acceptable. The limitations on sea loch type environments may, however, be less restrictive.
Experimental study of the incidence effect on rotating turbine blades
Authors: Cho Soo-Yong , Choi Sang-Kyu
Published: December 2004

Incidence is an important design parameter in the design of turbine blades, and many experiments have been conducted to ascertain an optimum incidence. However, most experiments were conducted in linear or annual cascade rows. From those experiments, one can recognize an optimum incidence that can minimize pressure losses in the passage. However, the optimum incidence suggested by the experimental results in the cascade rows could be unsuitable as a design parameter in the design of rotating parts. In this study, a turbine rotor instead of the cascade rows is used to find an optimum incidence in a rotating state. An experiment is conducted in a low-pressure and cold state with a single-stage axial-type turbine. The rotational speed and turbine output power are controlled by a dynamometer. Total-to-total efficiencies are obtained at several off-design points. Mass flow rate, torque, rotational speed, pressures and temperatures are measured at inlet or exit. Five different rotor discs are used to get some variation of blade inlet angle so that the rotor operates with different incidence even though it rotates at the same speed; that is, five cases are tested and compared with the total-to-total efficiencies obtained at various incidence angles. Experimental results show that the incidence on the rotor has a great influence on the turbine efficiency, and the optimum incidence depends on the input power as well as the rotor blade profile. The range of applicable incidence becomes narrow when the turbine operates at high input power, and turbine efficiency quickly drops down as the incidence grows to negative over the range of applicable incidence.
Z-Tribenzo[c,g,k]-1,2,5,6-tetradehydro[12]annulene, a Concave π-Electron System
Authors: Iyoda Masahiko , Fuchigami Kazuyuki , Kusaka Ayako , Yoshida Tadahiro , Yoshida Masato , Matsuyama Haruo , Kuwatani Yoshiyuki
Published: December 2004

Synthesis of Z-tribenzo[c,g,k]-1,2,5,6-tetradedydro[12]-annulene 1 has been carried out in a good total yield. The Bergman reaction of the closely situated acetylene bonds in the endiyne structure of 1 and the reaction of 1 with AuCl produced the corresponding cyclization products.
New Insulin-Mimetic Zinc (II) Complexes; Bis-maltolato Zinc(II) and Bis-(2-hydroxypyridine-N-oxido) Zinc(II) with Zn(O4) Coordination Mode
Authors: Yoshikawa Yutaka , Ueda Eriko , Kawabe Kenji , Miyake Hiroyuki , Sakurai Hiromu , Kojima Yoshitane
Published: December 2004

Zinc(II) complexes with a Zn(O4) coordination mode were found to have insulinomimetic activity. A bis-maltolato zinc(II) (Zn(Mal)2) complex was revealed to be in an octahedral and a square pyramidal geometries in a unit cell. Both Zn(Mal)2 (IC50 = 0.59 mM) and bis-2-hydroxypyridine-N-oxide zinc(II) (IC50 = 0.41 mM) complexes exhibited higher insulinomimetic activity than VOSO4(IC50 = 1.00 mM) and ZnSO4(IC50 = 0.81 mM) in terms of IC50 values, which show 50% inhibition concentration of the complex in the free fatty acids release from rat adipocytes.
Seneganolide, a Novel Antifeeding Mexicanolide from Khaya senegalensis
Authors: Nakatani Munehiro , Abdelgaleil Samir A M , Okamura Hiroaki , Iwagawa Tetsuo , Doe Matsumi
Published: December 2004

Seneganolide, a new mexicanolide type rings B,D-seco limonoid was isolated as insect antifeedant together with a known methyl angolensate from the stem bark of Kyaya senegalensis (Meliaceae). The structure was elucidated on the basis of spectroscopic means and the antifeedant activity was tested by a conventional leaf disk method.
Surface Reducibility of Cerium Oxide Modified with Palladium
Authors: Matsumura Yasuyuki , Shen Wen-Jie , Ichihashi Yuichi , Morisawa Yasuo , Okumura Mitsutaka
Published: December 2004

Three peaks at 530, 532, and 534 eV in the X-ray photoelectron spectrum of O 1s region for palladium-modified cerium oxide after reduction with hydrogen at 573 K can be attributed to Ce4+–O–Ce4+, Ce4+–O–Ce3+, and Ce3+–O–Ce3+ on the surface, respectively.
Synthesis and Molecular Structure of a Dilithium Salt of the cis-Diphenylcyclobutadiene Dianion
Authors: Matsuo Tsukasa , Mizue Takeru , Sekiguchi Akira
Published: December 2004

The cis-diphenyl-substituted cyclobutadiene cobalt complex (1), prepared from the reaction of 1,8-diphenyl-3,6-disila-1,7-octadiyne with CpCo(CO)2, reacted with lithium metal in tetrahydrofuran (THF) to yield pale orange crystals of the dilithium salt of the cis-diphenylcyclobutadiene dianion (2). The structure was determined by spectroscopic methods and X-ray crystallography to reveal the aromatic character of the doubly-charged four-membered ring system.
Transient Spectroscopic Properties of Endohedral Metallofullerenes, La@C82 and La2@C80
Authors: Fujitsuka Mamoru , Ito Osamu , Kobayashi Kaoru , Nagase Shigeru , Yamamoto Kazunori , Kato Tatsuhisa , Wakahara Takatsugu , Akasaka Takeshi
Published: December 2004

Properties of the excited states of endohedral metallofullerenes (La@C82 and La2@C80) have been investigated by time-resolved absorption spectroscopy. Transient absorption bands of La@C82 showed two decay-components, which were attributed to excited states of different spin multiplicity. The properties of photoexcited states of La2@C80 are also reported.
Oxidation of Hydrocarbons by Mono- and Dinuclear Ruthenium Quinone Complexes via Hydrogen Atom Abstraction
Authors: Wada Tohru , Tsuge Kiyoshi , Tanaka Koji
Published: December 2004

Deprotonation and two-electron oxidation of [RuII2(OH)2(Q)2(btpyan)]2+ (Q = 3,6-di(tert-butyl)-1,2-quinone, btpyan = 1,8-bis(2,2′:6′,2″-terpyridyl)anthracene) was converted to bis(ruthenium–oxo) complex [RuII2(O)2(Q)2(btpyan)]2+, which oxidized 1,3-cychrohexadiene and 1,2-dihydronaphtalene to corresponding aromatic compounds in the presence of AgClO4 and t-BuOK. On the other hand, mononuclear complex [RuII(OH2)(Q)(Ph-terpy)]2+ (Ph-terpy = 4′-phenyl-2,2′: 6′,2″-terpyridine, [2]2+) was converted to [RuII(OH)(Q)(Ph-terpy)]2+ under the similar conditions, but displayed the low activity for the oxidation compared with the dinuclear complex [1]2+.
Highly Conductive Room Temperature Molten Salts Based on Small Trimethylalkylammonium Cations and Bis(trifluoromethylsulfonyl)imide
Authors: Matsumoto Hajime , Yanagida Masahiro , Tanimoto Kazumi , Nomura Masakatsu , Kitagawa Yukiko , Miyazaki Yoshinori
Published: December 2004

The electrochemically stable and relatively high conductive room temperature molten salts (RTMS) have been obtained with the use of small ammonium cations such as methoxymethyltrimethylammonium and bis(trifluoromethylsulfonyl)imide. The RTMS showed high conductivity (4.7 mS cm−1 at 25 °C) which is the highest value of all the ammonium based RTMS reported so far.
Thenoyltrifluoroacetonato 1,10-Phenanthroline Europium (III) Complex Immobilized in Fluoropolymer Film as Optical Oxygen Sensing Material
Authors: Amao Yutaka , Okura Ichiro , Miyashita Tokuji
Published: December 2004

A new optical oxygen sensor based on the luminescence intensities of thenoyltrifluoroacetonato 1,10-phenanthroline europium (III) complex (Eu(TTA)3phen) immobilized in poly(styrene-co-trifluoroethylmethacrylate) film was developed. The luminescence intensity of the Eu(TTA)3phen film decreased with increasing the oxygen concentration. A Stern–Volmer plot of the Eu(TTA)3phen film exhibited considerable linearity (r2 = 0.996) and the Stern–Volmer quenching constant, KSV is estimated to be 0.015 %−1.
Synthesis of a Novel Ionic Liquid Crystalline Polythiophene Having Viologen Side Chain
Authors: Kijima Masashi , Setoh Kenichi , Shirakawa Hideki
Published: December 2004

A novel polythiophene having an ionic viologen mesogenic side chain at the 3-position was synthesized from a 2,5-dibromo-thiophene derivative by dehalogenative polycondensation using Ni(cod)2. Redox function of the viologen moiety in the polymer was confirmed by cyclic voltammetry. The polymer showed liquid crystalline, electrical conductive and photoelectrical properties.
A Sandwich Cubane-Type Mo–Sn Cluster: Synthesis and Crystal Structure of [(H2O)9Mo3OS3SnS3Omo3(H2O)9](CH3C6H4SO3)8·18H2O
Authors: Qin Yeyan , Wu Ling , Li Zhaoji , Kang Yao , Tang Yanhong , Yao Yuangen
Published: December 2004

A novel sandwich cubane-type mixed-metal Mo–Sn cluster compound [Mo6SnO2S6(H2O)18](pts)8·18H2O (A) was synthesized by the reaction of [Mo3(µ3-S)(µ-O)(µ-S)2(H2O)9]4+ (B) with tin metal in p-toluensulphonic acid (Hpts) solution. The compound A was characterized by the X-ray structure determination and UV–vis spectrum.
Face Selectivity in the Borohydride Reduction of 4-eq,6-ax-Diaryl-5-azaadamantan-2-ones
Authors: Jiménez-Cruz Federico , Cetina Raúl , Ríos-Olivares Héctor
Published: December 2004

The highly preferential attack at the en face in the reduction with sodium borohydride of 4-eq,6-ax-diaryl-5-azaadamantan-2-ones in methanol is described. Steric and electronic effects are involved.
New Cyclization Reaction of 2-(Trimethylsilylmethyl)pentadienal. Synthesis of Spiro[4.5]decane Ring System
Authors: Kuroda Chiaki , Koshio Hiroyuki
Published: December 2004

4-Cyclohexylidene-2-(trimethylsilylmethyl)but-2-enal, allylsilane type of linearly conjugated pentadienal, underwent a new self-cyclization reaction to afford 2-methylspiro[4.5]-2-decen-1-one. The reaction of 4-(4-alkylcyclohexylidene)-2-(trimethylsilylmethyl)-2-butenal proceeded stereoselectively.
A Bilayer Formed by Soluble Amphiphiles with Single Chain at the Mica–Solution Interface
Authors: Kawasaki Hideya , Syuto Masamitsu , Maeda Hiroshi
Published: December 2004

We investigated the aggregate morphologies of tetradecyldimethylamine oxide hemihydrochloride (C14DAO·1/2HCl) on mica surface in the surfactant solutions by Atomic Force Microscopy (AFM). C14DAO·1/2HCl forms a flat bilayer on mica. This morphology is different from spheres or cylinders which have been reported for other cationic surfactants with a single tetradecyl tail. The reason for this lower curvature of the C14DAO·1/2HCl aggregate on mica is discussed in terms of the hydrogen bond between the headgroups.
Evidence for the Formation of Hydrogen by Surface Reaction between Hydroxyl Groups and CO Molecule over Ga2O3–Al2O3
Authors: Haneda Masaaki , Joubert Emmanuel , Ménézo Jean-Christophe , Duprez Daniel , Barbier Jacques , Bion Nicolas , Daturi Marco , Saussey Jacques , Lavalley Jean-Claude , Hamada Hideaki
Published: December 2004

Surface reaction of CO with Al2O3-supported metal oxide catalysts was studied. Reversible reduction/oxidation was observed for In2O3–Al2O3. Although the exposure of Ga2O3–Al2O3 to CO caused the formation of CO2, the successive reoxidation by O2 was not observed. This was accounted for by the reaction of surface hydroxyl groups on Ga2O3–Al2O3 with CO, leading to CO2 and H2.
The role of functional and molecular imaging in cancer drug discovery and development
Authors: Seddon B M , Workman P
Published: December 2004

Studies of pharmacokinetics (which is what the body does to the drug) and pharmacodynamics (which is what the drug does to the body) are essential components of the modern process of cancer drug discovery and development. Defining the precise relationship between pharmacokinetics and pharmacodynamics is critical. It is especially important to establish a well understood pharmacological “audit trail” that links together all of the essential parameters of drug action, from the molecular target to the clinical effects. The pharmacological audit trail allows us to answer two absolutely crucial questions: (1) how much gets there; and (2) what does it do? During the pre-clinical drug discovery phase, it is essential that pharmacokinetic/pharmacodynamic (PK/PD) properties are optimized, so that the best candidate can be selected for clinical development. As part of contemporary mechanistic, hypothesis-testing clinical trials, construction of the pharmacological PK/PD audit trail facilitates rational decision-making. However, PK/PD endpoints frequently require invasive sampling of body fluids and tissues. Non-invasive molecular measurements, e.g. using MRI or spectroscopy, or positron emission tomography, are therefore very attractive. This review highlights the need for PK/PD endpoints in modern drug design and development, illustrates the value of PK/PD endpoints, and emphasises the importance of non-invasive molecular imaging in drug development. Examples cited include the use of PK/PD endpoints in the development of molecular therapeutic drugs such as the Hsp90 molecular chaperone inhibitor 17AAG, as well as the development of SR-4554 as a non-invasive probe for the detection of tumour hypoxia.
Molecular imaging using magnetic resonance: new tools for the development of tumour therapy
Authors: Brindle K M
Published: December 2004

Molecular imaging – the exploitation of specific molecules as the source of image contrast – promises new insights into disease processes in the laboratory and since the imaging modalities employed are applicable clinically, can be used to translate this knowledge into new diagnostics and treatments in the clinic. This brief review focuses on the use of MR-based molecular imaging techniques for developing tumour therapy. As examples, methods for detecting drug-induced tumour cell apoptosis; the response of tumours and their susceptibilities to an antivascular drug; early signs of tumour immune rejection and methods for detecting immune cell infiltration of tumours are described.
The role of ultrasound in molecular imaging
Authors: Liang H-D , Blomley M J K
Published: December 2004

Ultrasound has received less attention than other imaging modalities for molecular imaging, but has a number of potential advantages. It is cheap, widely available and portable. Using Doppler methods, flow information can be obtained easily and non-invasively. It is arguably the most physiological modality, able to image structure and function with less sedation than other modalities. This means that function is minimally disturbed, and multiple repeat studies or the effect of interventions can easily be assessed. High frame rates of over 200 frames a second are achievable on current commercial systems, allowing for convenient cardiac studies in small animals. It can be used to guide interventional or invasive studies, such as needle placement. Ultrasound is also unique in being both an imaging and therapeutic tool and its value in gene therapy has received much recent interest. Ultrasound biomicroscopy has been used for in utero imaging and can guide injection of virus and cells. Ultrahigh frequency ultrasound can be used to determine cell mechanical properties. The development of microbubble contrast agents has opened many new opportunities, including new functional imaging methods, the ability to image capillary flow and the possibility of molecular targeting using labelled microbubbles.
Antimuscarinic Intoxication Resulting from the Ingestion of Moonflower Seeds
Authors: DeFrates Lynn J , Hoehns James D , Sakornbut Ellen L , Glascock Daniel G , Tew Amanda R
Published: December 2004

OBJECTIVE:

To report a case in which ingestion of moonflower seeds resulted in antimuscarinic intoxication.

CASE SUMMARY:

An 18-year-old man was found at a local convenience store hallucinating and incoherent. Upon presentation to the emergency department, his signs and symptoms included tachycardia, confusion, dilated pupils, and dry, flushed, hot skin. He was admitted to the intensive care unit. Hallucinations and symptoms resolved within 36–48 hours after hospitalization. The patient then reported that he had ingested moonflower seeds. He recovered and was released 4 days after admission.

DISCUSSION:

Based on the patient's description and clinical presentation, the moonflower seeds were believed to be Datura inoxia. This species of plant is similar to jimson weed, or Datura stramonium. These plants are known to contain high concentrations of anticholinergic substances; ingestion can result in anticholinergic intoxication. Signs and symptoms that commonly occur include hallucinations, tachycardia, dilated pupils, and disorientation. In our patient, use of the Naranjo probability scale indicated a possible relationship between the moonflower seed ingestion and the patient's signs and symptoms.

CONCLUSIONS:

Ingestion of the Datura species can result in severe toxicity. Each plant varies in the concentrations of alkaloid substances. For this reason, it is very important for individuals to become educated on the toxicities and potential risks associated with recreational use of these plants.
The Impact of New Drug Introduction on Drug Expenditure in Primary Health Care in Catalunya, Spain
Authors: Zara Corinne , Torralba Miguel , Sotoca José M , Prat Alba , Faixedas María-Teresa , Gilabert Antoni
Published: December 2004

BACKGROUND:

Introduction of new drugs is a dynamic process with a high impact on consumption and expenditure.

OBJECTIVE:

To analyze the prescription of new drugs and the associated costs in public health care in Catalunya, Spain, in 2002. The analysis also attempts a perspective of consumption in relation to the grade of therapeutic innovation of the new drugs.

METHODS:

Prescription data on all 86 new drugs licensed for use during 1998–2002 were analyzed, using the prescription item as unit and the cost.

RESULTS:

Prescription for new drugs in 2002 represented 4% of overall items prescribed and 13% of the cost. The mean new drug item cost was ¢39, while that of overall drugs was ¢13. New drug item increase over the previous year was 18.6% compared with 5.2% of the overall drugs, and the proportional cost increased by 25.7% and 9.9%, respectively. Ten new drugs represented 55.1% of the expenditure of this group. Antiasthmatic drugs represented 20.7% of the expenditure on new drugs, angiotensin-receptor blockers represented 18.6%, antiaggregants 9.7%, and nonsteroidal antiinflammatory drugs 6.9%. New drugs providing significant or modest therapeutic improvement represented 25.6% of overall new drug items and 32.3% of their cost.

CONCLUSIONS:

New drugs have a mean cost growth rate greater than that of existing drugs, with only a quarter of them offering advantages over existing drugs. More detailed evaluations of new medications are warranted before they can be recommended for general use so that a better distribution of the limited resources available may be made when prescribing drugs that are newly available through prescription.
A Device for Studying Fresh Concrete Friction
Authors: Vanhove Y , Djelal C , Magnin A
Published: December 2004

Many civil engineering applications are confronted with problems caused by friction (wear, head losses, etc.). A tribometer for fluid material was therefore developed. The principle consists in pressing fresh concrete samples against a moving metal surface and measuring the tangential force. The validation of this new instrumentation is presented. Results obtained on two concretes show that the friction does not follow Coulomb's Law. The main parameters (pressure, velocity) involved during formwork filling are taken into account.
Effect of Finishing Practices on Performance of Concrete Containing Slag and Fly Ash as Measured by ASTM C 672 Resistance to Deicer Scaling Tests
Authors: Taylor PC , Morrison W , Jennings VA
Published: December 2004

The test method was developed to evaluate portland cement systems with different air contents, and for the purpose of determining whether the apparent poor performance of concretes containing supplementary cementing materials in the ASTM C 672 deicer scaling test can be attributed to differences in finishing effort or timing of finishing, or both.