bluuebunny/crossref_metadata_2025 huggingface dataset:
Sleep inducing effect of low energy emission therapy
Authors: Reite M. , Higgs L. , Lebet J.‐P. , Barbault A. , Rossel C. , Kuster N. , Dafni U. , Amato D. , Pasche B.
Published: February 2006

The sleep inducing effect of a 15 min treatment with either an active or an inactive Low Energy Emission Therapy (LEET) device emitting amplitude‐modulated electromagnetic (EM) fields was investigated in a double‐blind cross‐over study performed on 52 healthy subjects. All subjects were exposed to both active and inactive LEET treatment sessions, with an interval of at least I week between the two sessions. LEET consists of 27.12 MHz amplitude‐modulated (sine wave) EM fields emitted intrabuccally by means of an electrically conducting mouthpiece in direct contact with the oral mucosa. The estimated local peak SAR is less than 10 W/kg in the oral mucosa and 0.1 to 100 mW/kg in brain tissue. No appreciable sensation is experienced during treatment, and subjects are therefore unable to tell whether they are receiving an active or an inactive treatment. In this study the active treatment consisted of EM fields intermittently amplitude‐modulated (sine wave) at 42.7 Hz for 3 s followed by a pause of 1 s during which no EM fields were emitted. During the inactive treatment no EM fields were emitted. Baseline EEGs were obtained and 15 min post‐treatment EEGs were recorded and analyzed according to the Loomis classification.

A significant decrease (pairedttest) in sleep latency to stage B2 (−1.78 ± 5.57 min,P= 0.013), and an increase in the total duration of stage B2 (1.15 ± 2.47 min,P= 0.0008) were observed on active treatment as compared with inactive treatment. The deepest sleep stage achieved (B1 to D) following active treatment was also significantly higher than that following inactive treatment (P= 0.040). We conclude 27.12 MHz electromagnetic fields, intermittenly amplitude‐modulated at 42.7 Hz, result in a significant sleep inducing effect in healthy subjects. © 1994 Wiley‐Liss, Inc.
Superimposing spatially coherent electromagnetic noise inhibits field‐induced abnormalities in developing chick embryos
Authors: Litovitz T. A. , Montrose C. J. , Doinov P. , Brown K. M. , Barber M.
Published: February 2006

Living cells exist in an electrically noisy environment. This has led to the so‐called “signal‐to‐noise” problem whereby cells are observed to respond to extremely‐low‐frequency (ELF) exogenous fields that are several orders of magnitude weaker than local endogenous fields associated with thermal fluctuations. To resolve this dilemma, we propose that living cells are affected only by electromagnetic fields that are spatially coherent over their surface. The basic idea is that a significant number of receptors must be simultaneously and coherently activated (biological cooperativity) to produce effects on the biochemical functioning of the cell. However, like all physical detection systems, cells are subject to the laws of conventional physics and can be confused by noise. This suggests that a spatially coherent but temporally random noise field superimposed on a coherent ELF signal will defeat the mechanism of discrimination against noise, and any observed field‐induced bioeffects would be suppressed. An experimental test of this idea was conducted using morphological abnormalities in developing chick embryos caused by electromagnetic field exposure as the endpoint. At an impressed noise amplitude comparable to the ELF field strength (but roughly one‐thousandth of the thermal noise field), the increased abnormality rate observed with only the ELF field present was reduced to a level essentially the same as for the control embryos. © 1994 Wiley‐Liss, Inc.
Correlations among indices of electric and magnetic field exposure in electric utility workers
Authors: Savitz David A. , Ohya Takao , Loomis Dana P. , Senior Russell S. , Dan Bracken T. , Howard Richard L.
Published: February 2006

Power‐frequency electric and magnetic fields are known to exhibit marked temporal variation, yet in the absence of clear biological indications, the most appropriate summary indices for use in epidemiologic studies are unknown. In order to assess the statistical patterns among candidate indices, data on 4383 worker‐days for magnetic fields and 2082 worker‐days for electric fields collected for the Electric and Magnetic Field Project for Electric Utilities using the EMDEX meter [Bracken (1990): Palo Alto, CA: Electric Power Research Institute] were analyzed. We examined correlations at the individual and job title group levels among indices of exposure to both electric and magnetic fields, including the arithmetic mean, geometric mean, median, 20th and 90th percentiles, time above lower cutoffs of 20 V/m and 0.2 μT, and time above higher cutoffs of 100 V/m and 2.0 μT. For both electric and magnetic fields, the arithmetic mean was highly correlated with the 90th percentile; moderately correlated with the geometric mean, median, and lower and higher cutoff scores; and weakly correlated with the 20th percentile. Electric and magnetic field indices were generally weakly correlated with one another. Rank‐order correlation coefficients were consistently greater than product‐moment correlation coefficients. Job title group summary scores showed higher correlations among electric field indices and magnetic field indices and between electric and magnetic field indices than was found for individual worker‐days, with only the 20th percentile clearly independent of the others. These results suggest that individuals' exposures are adequately characterized by a measure of central tendency for electric and magnetic fields, such as the arithmetic or geometric mean, and an indicator of a lower threshold or cutoff for each field type, such as the 20th percentile or proportion of time above 20 V/m or 0.2 μT. A single measure of central tendency for each type of field appears to be adequate when exposures are assessed at the job title level. © 1994 Wiley‐Liss, Inc.
Effects of extremely‐low‐frequency magnetic fields on biological magnetite
Authors: Polk Charles
Published: February 2006

Adair [Bioelectromagnetics 14:1–4, 1993] writes that “the effects of 60 Hz magnetic fields of 5 μT (50 mG) or less on biological structures holding magnetite (Fe3O4) are shown to be much smaller than those from thermal agitation; hence such interactions cannot be expected to be biologically significant.” This conclusion is questioned, because it appears to be based on a model that probably has very limited validity for pertinent biological systems. Furthermore, biologically plausible parameters can be selected to show that even this particular model does not exclude biologically significant effects of 60 Hz magnetic fields below 5 μT. Reported experimental results indicate effects in mammals of 50 Hz fields at the 1 μT level. © 1994 Wiley‐Liss, Inc.
Exposure of simian virus‐40‐transformed human cells to magnetic fields results in increased levels of T‐antigen mRNA and protein
Authors: Gold Steven , Goodman Reba , Shirley‐Henderson Ann
Published: February 2006

In its integrated form, SV‐40 DNA offers an opportunity to observe the behavior of what is in effect a viral genome within a cellular genome, with transcriptional and translational products that can be clearly distinguished from those of the host cell. Exposure of SV40‐transformed human fibroblasts to a 60 Hz continuous‐wave sinusoidal electromagnetic (EM) field resulted in increased levels of virally derived mRNA and protein of large T‐antigen. These findings provide evidence that a foreign DNA integrated into cells can be affected by EM fields under conditions known to cause increased transcripts from endogenous cellular genes. © 1994 Wiley‐Liss, Inc.
Spreadsheet method for calculating the induced currents in bone‐fracture healing by a low‐frequency magnetic field
Authors: Hart Francis X.
Published: February 2006

A commercially available spreadsheet program is used on a microcomputer to calculate the induced current density and electric field patterns produced in a nonhomogeneous, anisotropic model of tissue by a localized, low‐frequency magnetic field source. Specific application is made to coils used to promote the healing of bone fractures in limbs. The variation of the conductivity of the fracture gap during healing causes the induced current density pattern to change correspondingly, whereas the induced electric field remains relatively unchanged. Use of more simplified, isotropic models for the bone and for the soft tissue leads to results that differ significantly from those obtained from the full model. The magnetic field beyond the region of the coils contributes little to the induced currents in the fracture gap if the gap is located near the center of the coils. © 1994 Wiley‐Liss, Inc.
Stochastic resonance as a possible mechanism of amplification of weak electric signals in living cells
Authors: Kruglikov Ilya L. , Dertinger Hermann
Published: February 2006

The most important but still unresolved problem in bioelectromagnetics is the interaction of weak electromagnetic fields (EMFs) with living cells. Thermal and other types of noise pose restrictions in cell detection of weak signals. As a consequence, some extant experimental results that indicate low‐intensity field effects cannot be accounted for, and this renders the results themselves questionable. One way out of this dead end is to search for possible mechanisms of signal amplification. In this paper, we discuss a general mechanism in which a weak signal is amplified by system noise itself. This mechanism was discovered several years ago in physics and is known, in its simplest form, as a stochastic resonance. It was shown that signal amplification may exceed a factor of 1000, which renders existing estimations of EMF thresholds highly speculative. The applicability of the stochastic resonance concept to cells is discussed particularly with respect to the possible role of the cell membrane in the amplification process. © 1994 Wiley‐Liss, Inc.
Design and fabrication of well confined uniform magnetic field exposure systems
Authors: Wilson Bary W. , Caputa Kris , Stuchly Maria A. , Saffer Jeffrey D. , Davis Karl C. , Washam Calvin E. , Washam Lloyd G. , Washam Glenn R. , Wilson Mark A.
Published: February 2006

Exposure systems that provide good magnetic field uniformity, minimum stray fields, and minimal heating, vibration, and hum, as well as capability for true sham exposure in which current flows in the coils, are needed to determine rigorously the biological effects of weak magnetic fields. Designs based on acrylic polymer coil support structures and twisted pair bifilary coil windings were employed to fabricate several different systems for the exposure of laboratory animals and cell cultures to magnetic fields. These systems exhibit excellent performance characteristics in terms of exposure field uniformity, stray field containment, and exposure field cancellation in the sham exposure mode. A custom‐written computer program was used to determine the best arrangement for coils with regard to field uniformity in the exposure volume and stray field containment. For in vivo exposures, modules were made up of four Merritt four‐coil sets, built into a single structure and positioned to form an octapole with fields directed in the horizontal plane. For in vitro applications, two different coil configurations were selected to produce the vertical fields required. A quadrupole system, comprising modules consisting of two Merritt four‐coil sets arranged side by side to limit stray fields, was built as a prototype. In the second configuration, one Merritt four‐coil set was positioned inside the other to form a concentric coil set. In both in vitro systems, exposure chambers were connected to remote commercial incubators in order to reduce ambient magnetic fields in the exposure volume. An active field cancellation circuit was developed for reducing ambient AC magnetic fields in the in vitro sham exposure chamber, when necessary. These design and fabrication approaches provide systems that offer uniform field exposures and excellent stray field containment when needed and are portable, washable, and relatively inexpensive. © 1994 Wiley‐Liss, Inc.

This article is a US Government work and, as such, is in the public domain in the United States of America.
Blockade of sensory neuron action potentials by a static magnetic field in the 10 mT range
Authors: McLean M. J. , Holcomb R. R. , Wamil A. W. , Pickett J. D. , Cavopol A. V.
Published: February 2006

To characterize the inhibitory effect of a static magnetic field, action potentials (AP) were elicited by intracellular application of 1 ms depolarizing current pulses of constant amplitude to the somata of adult mouse dorsal root ganglion neurons in monolayer dissociated cell culture. During the control period, <5% of stimuli failed to elicit AP. During exposure to an ˜11 mT static magnetic field at the cell position produced by an array of four permanent center‐charged neodymium magnets of alternating polarity (MAG‐4A), 66% of stimuli failed to elicit AP. The number of failures was maximal after about 200‐250 s in the field and returned gradually to baseline over 400–600 s. A direct or indirect effect on the conformation of AP generating sodium channels could account for these results because (I) failure was preceded often by reduction of maximal rate of rise, an indirect measure of sodium current; (2) recovery was significantly prolonged in more than one‐half of neurons that were not stimulated during exposure to the MAG‐4A field; and (3) resting membrane potential, input resistance, and chronaxie were unaffected by the field.

The effect was diminished or prevented by moving the MAG‐4A array along the X or Z axis away from the neuron under study and by increasing the distance between magnets in the XY plane. Reduction of AP firing during exposure to the ˜0.1 mT field produced by a MAG‐4A array of micromagnets was about the same as that produced by a MAG‐4A array of the large magnets above. The ˜28 mT field produced at cell position by two magnets of alternating polarity and the ˜88 mT field produced by a single magnet had no significant effect on AP firing. These findings suggest that field strength alone cannot account for AP blockade. © 1995 Wiley‐Liss, Inc.
Intracellular calcium oscillations in a T‐cell line after exposure to extremely‐low‐frequency magnetic fields with variable frequencies and flux densities
Authors: Lindström Ewa , Lindström Per , Berglund André , Lundgren Erik , Mild Kjell Hansson
Published: February 2006

Low‐frequency magnetic fields (MF) can increase the cytosolic calcium concentration ([Ca2+]i) in lymphocytes in the same manner as a physiological stimulus such as antibodies directed towards the CD3 complex. In this study, MF with various frequencies and flux densities were used, while [Ca2+]ichanges were recorded using microfluorometry with fura‐2 as a probe. The applied sinusoidal MF induced oscillatory changes of [Ca2+], in the leukemic cell line Jurkat in a manner similar to that seen with stimulation by antibodies. The response at 0.15 mT was over a frequency range from 5 to 100 Hz, with a fairly broad peak having its maximum at 50 Hz. The result of testing increasing flux densities at 50 Hz was a threshold response with no effect below 0.04 mT and a plateau at 0.15 mT. On the basis of the characteristic calcium pattern resulting from an applied MF, we suggest that MF influence molecular events in regular signal transduction pathways of T cells. © 1995 Wiley‐Liss, Inc.
A method for assessing alternative effects functions that uses simulation with EMDEX data
Authors: Morgan M. Granger , Nair Indira , Zhang Jun
Published: February 2006

A method for evaluating a variety of alternative biologically plausible effects functions through the use of simulation studies conducted on personal‐monitor exposure data is described. Using magnetic field time series collected with EMDEX instruments, we demonstrate how the method can be used to explore (1) how the outputs from various effects functions simulations compare to the results obtained by assuming that effects are proportional to time average field strength; (2) how the results of epidemiological studies might be used to assess the relative likelihood that each of the alternative effects functions describes biological reality; and (3) how the results might be used to assess possible health risks. Although the available data are sufficient to demonstrate the general method, they are not yet sufficient to support actual discrimination among possible alternatives. The arguments on the use of the method are for illustrative purposes only. © 1995 Wiley‐Liss, Inc.
3T3 cell motility and morphology before, during, and after exposure to extremely‐low‐frequency magnetic fields
Authors: Spadinger Ingrid , Agnew David , Palcic Branko
Published: February 2006

Automated image cytometry techniques were used to measure motility and morphology in 3T3 fibro‐blasts exposed to extremely‐low‐frequency (ELF) magnetic fields. Cell motility and morphology were measured as a function of time before, during, and after 3–4 hour exposures to vertically oriented, 100 μTRMS sinusoidal magnetic fields at various frequencies in the 10–63 Hz range. Sham exposures were also carried out. No static DC fields were applied, but the geomagnetic field was almost vertical and, therefore, had a large component (28.3 μT) parallel to the applied AC field. The morphology and motile behavior of the cells were characterized by mathematically defined descriptors, which were calculated and averaged for the exposure period as well as for control periods that preceded and followed the exposure period. Each experiment involved the tracking of 100 cells that were subjected to one of the test frequencies (unless a sham exposure was being conducted). Statistical analysis of the results showed that even small changes of 10–20% could be significant at the P <.05 level. Changes on this order were measured in a significant proportion of the experiments. However, because such results were seen for both the sham‐exposed and the ELF‐exposed cells, and because the range of values that was obtained for the sham exposures was the same as that obtained for the ELF exposures, we concluded that there was no evidence to show that any of the measured changes were attributable to the applied ELF magnetic field. © 1995 Wiley‐Liss, Inc.
Microwave influence on the isolated heart function: II. Combined effect of radiation and some drugs
Authors: Pakhomov Andrei G. , Dubovick Boris V. , Degtyariov Igor G. , Pronkevich Anatoly N.
Published: February 2006

The combined effects of microwave radiation and some drugs were studied in an isolated frog auricle preparation. The experiments established that exposure to pulse‐modulated 915 MHz microwaves for up to 40 min had no effect on either the rate or the amplitude of spontaneous auricle twitches, unless the average absorbed power was high enough to produce preparation heating. Treatment of the preparation with saline containing (0.6–3.0) 10−5 M of propranolol or (0.5–1.5) 10−7 M of atropine altered neither its pacemaker nor its contractile functions; these drugs also had no effect when they were combined with nonthermal microwave irradiation. Caffeine (1 mM) strongly increased the average heart power, which was calculated as the product of twitch rate and amplitude. The caffeine effect appeared to be significantly augmented (by about 15%, P<0.02) under exposure to burst‐type pulsed microwaves (pulse width, 1.5 msec; pause, 2.5 msec; 8 pulses/burst, 16 bursts/s; average SAR, 8–10 W/kg). By itself, this modulation was not effective; the heating of the preparation and saline during exposure was approximately 0.1°C, which could not account for the detected changes. The experimental results demonstrate that caffeine treatment increases the microwave sensitivity of the frog auricle preparation and reveals primarily subthreshold, nonthermal microwave effect. © 1995 Wiley‐Liss, Inc.
Spectral analysis of magnetic fields from domestic appliances and corresponding induced current densities in an anatomically based model of the human head
Authors: Tofani Santi , Anglesio Laura , Ossola Piero , d'Amore Giovanni
Published: February 2006

Magnetic fields emitted by electric appliances such as razors, hair dryers, and drills were measured in the frequency domain. Results show the presence of high‐frequency components (up to 96 kHz for razors, up to 3.4 kHz for hair dryers, and up to 8.6 kHz for drills) in the harmonic content of the fields. The measured fields were used to calculate the induced current densities in an anatomically based model of the human head (resolution 1.31 cm) by using the impedance method. The harmonic field contribution to the current density was higher than that from the carrier frequency for all the tested appliances. © 1995 Wiley‐Liss, Inc.
Residential exposure to magnetic fields generated by 110‐400 kV power lines in Finland
Authors: Valjus Jorma , Hongisto Mikko , Verkasalo Pia , Järvinen Pekka , Heikkilä Kauko , Koskenvuo Markku
Published: February 2006

In a specific case, the magnetic field generated in a building by a nearby power line is usually easy to calculate, although the accuracy of these calculations is sensitive to the quality of source information. To be able to study public health dimensions of magnetic field exposure (e.g., risk of cancer), it is necessary to evaluate the size and exposure of the population at risk. Relatively little quantitative information on public exposure to power‐frequency magnetic fields of high‐voltage power lines is available. This report describes residential exposure to magnetic fields from 110 kV, 220 kV, and 400 kV power lines in Finland at the national level, including 90% of the total line length in 1989. A geographical information system (GIS) was used to identify the buildings located near the power lines. After determining the distances between the lines and the buildings, historical data on load currents of these lines were used to calculate the magnetic fields. The residential magnetic field histories were then linked to the residents by means of a computerized central population register. The data obtained on personal exposure have also been utilized in a nationwide epidemiological study on magnetic field exposure of power lines and risk of cancer. The methods of exposure assessment and results of the number of buildings near 110 kV, 220 kV, and 400 kV power lines, their average annual magnetic fields, and personal exposure to magnetic fields from these lines are described. We found that 15,600 residents lived in an average residential magnetic field ≥0.1 μT caused by power lines in 1989. The number of these residents increased fivefold during 1970‐1989. We estimated that 0.3% of the population was exposed in their residences to an annual average magnetic flux density from 110 kV, 220 kV, and 400 kV power lines higher than 0.1 μT, the level that the background magnetic flux density in general does not exceed in Finnish homes. Thus, the problem of magnetic field exposure generated by high‐voltage lines concerns only a relatively small fraction of the total population in Finland. However, the size and exposure of the population at risk remain somewhat arbitrary in practical multisource situations, as the biological interaction mechanism, the concept of harmful dose, and, in particular, the significance of the duration of exposure are unknown. © 1995 Wiley‐Liss, Inc.
Designing EMF experiments: What is required to characterize “exposure”?
Authors: Valberg Peter A.
Published: February 2006

Anyone who has attempted to organize and synthesize the results of research on biological effects of electric and magnetic fields (EMF) has experienced frustration when trying to evaluate the comparability of EMF exposures among separate studies. Reporting of exposure characteristics is often incomplete, and some investigators focus on particular nuances of exposure, which in other laboratories go unrecorded because they are not regarded as important. The obstacles encountered when comparing studies, when designing replication studies, and when evaluating research proposals could be reduced were a more standardized approach taken in describing “EMF exposure.” To this end, a numerical listing of 18 separate parameters important to EMF exposure characterization is proposed. Although the goal of this list is primarily to expedite the description of EMF exposure, references are provided to examples of EMF exposures and to detailed discussions of EMF exposure systems. © 1995 Wiley‐Liss, Inc.
Review: Selective ligand‐exchange adsorbents prepared by template polymerization
Authors: Vidyasankar Sundaresan , Dhal Pradeep K. , Plunkett Sean D. , Arnold Frances H.
Published: February 2006

Highly selective ligand‐exchange absorbents have been prepared by template polymerization, a process in which the target molecule serves as a template for assembly of specific recognition sites. In an effort to develop materials suitable for chromatographic separations, thin coatings of the selctive templated polymers have been grafted to two reactive macroporous supports, poly(trimethylolpropane trimethacrylate) (TRIM), and propylmethacrylate‐derivatized silica beads. The precursor polymer prepared from the trifunctioal TRIM monomer is macroporous and highly crosslinked, providing a stable structure for surface grafting. The TRIM precursor polymer and various surface‐grafted copolymers have been characterized by scanning electron microscopy (SEM) and IR, 13C NMR, and XPS spectroscopic techniques. Composite adsorbents have also been prepared using propylmethacrylate‐modified silica particles. While equilibrium rebinding selectivites for both types of surface‐templated materials are similar to those reported previously for bulk‐polymerized template polymers, the composite materials are far better suited to chromatographic separatios. Highly similar bis‐imidazole substrates can be separated by ligand‐exchange chromatography on these new templated adsorbents. © 1995 John Wiley & Sons, Inc.
Protected amino acids as novel low‐molecular‐weight displacers in cation‐exchange displacement chromatography
Authors: Kundu Amitava , Vunnum Suresh , Jayaraman Guhan , Cramer Steven M.
Published: February 2006

Although the ability to carry out simultaneous concentration and purification in a single displacement step has significant advantages for downstream processing of pharmaceuticals, a major impediment to the implementation of displacement chromatography has been the lack of suitable displacer compounds. An important recent advance in the state of the art of displacement chromatography has been the discovery that low‐molecular‐weight dendritic polymers can be successfully employed as displacers for protein purification in ion‐exchange systems. In this article, protected amino acid esters (based on arginine and lysine) are shown to be useful displacers for protein purification in cation‐exchange systems. A dynamic affinity plot is employed to evaluate the affinity of these low‐molecular‐weight compounds under dis‐placement conditions. In contrast to large polyelectroyte displacers, the efficacy of these low‐molecular‐weight displacers was shown to be dependent on both the initial carrier salt concentration and the displacer concentration. In addition to the funcamental interest generated by low‐molecular‐weight displacers, it is likely that these displacers will have significant operatioal advantages as compared with large polyelectrolyte displacers. © 1995 John Wiley & Sons, Inc.
Approaches for increasing the solution stability of proteins
Authors: Manning Mark C. , Matsuura James E. , Kendrick Brent S. , Meyer Jeffrey D. , Dormish Jonathon J. , Vrkljan Michael , Ruth James R. , Carpenter John F. , Sheftert Eli
Published: February 2006

Stabilization of proteins through proper formulation is an important challenge for the pharmaceutical industry. Two approaches for stabilization of proteins in solution are discussed. First, work describing the effect of additives on the thermally induced denaturation and aggregation of low molecular weight urokinase is presented. The effects of these additives can be explained by preferential exclusion of the solute from the protein, leading to increased thermal stability with respect to denaturation. Diminished denaturation leads to reduced levels of aggregation. The second approach involves stoichiometric replacement of polar counter ions (e.g., chloride, acetate, etc.) with anionic detergents, in a process termed hydrophobic ion pairing (HIP). The HIP complexes of proteins have increased solubility in organic solvents. In these organic solvents, where the water content is limited, the thermal denautration temperatures greatly exceed those observed in aqueous solution. In addition, it is possible to use HIP to selectively precipitate basic proteins from formulations that contain large amounts of stabilizers, such as human serum albumin (HSA), with a selectivity greater than 2000‐fold. This has been demonstrated for various mixtures of HSA and interleukin‐4. © 1995 John Wiley & Sons, Inc.
Computer‐aided process analysis and economic evaluation for biosynthetic human insulin production—A case study
Authors: Petrides Demetri , Sapidou Elpida , Calandranis John
Published: February 2006

Human insulin was the first mammalian protein produced in bacteria using recombinant DNA technology. Two technologies were developed; the first based on the separate expression of precursors of chains A and B of insulin, and the second based on the expression of a precursor of proinsulin as a Trp‐E fusion protein. Both technologies utilized Escherichia coli as an expression system. Later, a third technology was developed based on a strain of yeast that can secrete a precursor of insulin. The second E. coli process, a variation of which has been commercialized by Eli Lilly and Co., is analyzed in this article from a process design and economic evaluation viewpoint. The objective of this work is to elucidate the technical complexity and high cost associated with the manufacturing of biopharmaceuticals. Human insulin is a good example of a protein‐based biopharmaceutical produced in large quantities (a fex tons per year) that requires large scale equipment and presents a multitude of scale‐up challenges. Based onthe analysis, a number of conclusions are drawn regarding the cost breakdown and cost dependency on process parameters. Recommendations are made for cost reduction and environmental impact minimization. This analysis was performed using a software tool for computer‐aided bioprocess design. © 1995 John Wiley & Sons, Inc.
Unprecedented ROMP Activity of Low‐Valent Rhenium–Nitrosyl Complexes: Mechanistic Evaluation of an Electrophilic Olefin Metathesis System
Authors: Frech Christian M. , Blacque Olivier , Schmalle Helmut W. , Berke Heinz , Adlhart Christian , Chen Peter
Published: February 2006

The reaction of [Re(H)(NO)2(PR3)2] complexes (1 a: R = PCy3; 1 b: R = PiPr3) with [H(OEt2)2][BArF4] ([BArF4] = tetrakis{3,5‐bis(trifluoromethyl)phenyl}borate) in benzene at room temperature gave the corresponding cations [Re(NO)2(PR3)2][BArF4] (2 a and 2 b). The addition of phenyldiazomethane to benzene solutions of 2 a and 2 b afforded the moderately stable cationic rhenium(I)‐benzylidene‐dinitrosyl‐bis(trialkyl)phosphine complexes 3 a and 3 b as [BArF4]− salts in good yields. The complexes 2 a and 2 b catalyze the ring‐opening metathesis polymerization (ROMP) of highly strained nonfunctionalized cyclic olefins to give polymers with relatively high polydispersity indices, high molecular weights and over 80 % Z configuration of the double bonds in the chain backbone. However, these complexes do not show metathesis activity with acyclic olefins. The benzylidene derivatives 3 a and 3 b are almost inactive in ROMP catalysis with norbornene and in olefin metathesis. NMR experiments gave the first hints of the initial formation of carbene complexes from [Re(NO)2(PR3)2][BArF4] (2 a and 2 b) and norbornene. In a detailed mechanistic study ESI‐MS/MS measurements provided further evidence that the carbene formation is initiated by a unique reaction sequence where the cleavage of the strained olefinic bond starts with phosphine migration forming a cyclic ylide–carbene complex, capable of undergoing metathesis with alternating rhenacyclobutane formation and cycloreversion reactions (“ylide” route). However, even at an early stage the ROMP propagation route is expected to merge into an “iminate” route by attack by the ylide function on one of the NNO atoms followed by phosphine oxide elimination. The formation of phosphine oxide was confirmed by NMR spectroscopy. The proposed mechanism is supported further by detailed DFT calculations.
Infrared‐Spectroscopic and Density‐Functional‐Theory Investigations of the LaCO, La2[η2(μ2‐C,O)], and c‐La2(μ‐C)(μ‐O) Molecules in Solid Argon
Authors: Xu Qiang , Jiang Ling , Zou Ru‐Qiang
Published: February 2006

Reactions of laser‐ablated lanthanum atoms with CO molecules in solid argon have been studied. The neutral lanthanum monocarbonyl (LaCO), produced upon sample deposition at 7 K, exhibits a CO stretching frequency of 1772.7 cm−1; to the best of our knowledge this is the lowest yet observed for a terminal CO in a neutral metal–carbonyl molecule (MCO, M=metal atom), implying anomalously enhanced metal‐to‐CO back‐bonding. The infrared (IR) absorption band at 1145.9 cm−1 is assigned to the CO stretching mode of the side‐on‐bonding CO in the La2[η2(μ2‐C,O)] molecule. This CO‐activated molecule undergoes an UV/Vis‐photoinduced rearrangement to the CO‐dissociated molecule, c‐La2(μ‐C)(μ‐O). Density functional theory (DFT) calculations have been performed on these molecules, the results of which lend strong support to the experimental assignments of the IR spectra. LaCO is predicted to have a quartet ground state, corresponding to a linear geometry. Its formation involves La 6s→4f promotion, which increases the strength of LaCO bonding by decreasing the σ repulsion and, remarkably, by increasing the La 5d and 4f→CO 2π back‐bonding. The observations schematically depict the whole process, starting with the interaction of CO with metal and ending with CO dissociation by the lanthanum dimer.
Platinum‐ and Gold‐Catalyzed Rearrangement Reactions of Propargyl Acetates: Total Syntheses of (−)‐α‐Cubebene, (−)‐Cubebol, Sesquicarene and Related Terpenes
Authors: Fürstner Alois , Hannen Peter
Published: February 2006

Propargyl acetates, in the presence of catalytic amounts of late transition‐metal salts such as PtCl2 or AuCl3, represent synthetic equivalents of α‐diazoketones. This notion is corroborated by a concise approach to various sesquiterpene natural products starting from readily available substrates. Specifically, (+)‐carvomenthone (17) is converted into propargyl acetate (S)‐26 by a sequence involving Stille cross‐coupling of its kinetic enol triflate 18, regioselective hydroboration/oxidation of the resulting 1,3‐diene 19, and addition of an alkynyl cerium reagent to aldehyde 21 thus obtained. Since the latter step was found to be unselective, the configuration of the reacting propargyl acetate was unambiguously set by oxidation followed by diastereoselective transfer hydrogenation by using Noyori's catalyst 25. Compound (S)‐26, on treatment with PtCl2 in toluene, converted exclusively to the tricyclic enol acetate 27, which was saponified to give norcubebone 11 in excellent overall yield. The conversion of this compound into the sesquiterpene alcohol (−)‐cubebol (6) was best achieved with MeCeCl2 as the nucleophile, whereas the formation of the parent hydrocarbon (−)‐α‐cubebene (4) was effected in excellent yield by recourse to iron‐catalyzed cross coupling methodology developed in this laboratory. Since norketone 11 has previously been transformed into (−)‐β‐cubebene (5) as well as (−)‐4‐epicubebol 8, our approach constitutes formal total syntheses of these additional natural products as well. Along similar lines, the readily available propargyl acetates 1, 33 and 47 were shown to give access to 2‐carene 44, sesquicarene 39, and episesquicarene 51 in excellent overall yields. In this series, however, the cycloisomerization reaction was best achieved with catalytic amounts of AuCl3 in 1,2‐dichloroethane as the solvent. In addition to these preparative results, our data provide some insight into the mechanism of these remarkable skeletal rearrangement reactions. Transformations of this type are likely triggered by initial coordination of the alkyne unit of the substrate to the carbophilic transition‐metal cation. Formal attack of the alkene moiety onto the resulting π‐complex engenders the formation of an electrophilic cyclopropyl carbene species which subsequently reacts with the adjacent acetate unit to give the final product. The alternative phasing of events, implying initial attack of the acetate (rather than the alkene moiety) onto the metal–alkyne complex, is inconsistent with the stereochemical data obtained during this total synthesis campaign.
Three Alkali‐Metal Erbium Thiophosphates: From the Layered Structure of KEr[P2S7] to the Three‐Dimensional Cross‐Linkage in NaEr[P2S6] and Cs3Er5[PS4]6.
Authors: Komm Theresa , Schleid Thomas
Published: February 2006

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
K2M (H2P2O7)2×2H2O (M: Ni, Cu, Zn): Orthorhombic Forms and Raman Spectra.
Authors: Essehli Rachid , El Bali Brahim , Tahiri Aziz Alaoui , Lachkar Mohammed , Manoun Bouchaib , Dusek Michal , Fejfarova Karla
Published: February 2006

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
A Molecular Dynamics Study of the Thermodynamic Properties of Calcium Apatites. Part 1. Hexagonal Phases.
Authors: Cruz Fernando J. A. L. , Canongia Lopes Jose N. , Calado Jorge C. G. , Minas da Piedade Manuel E.
Published: February 2006

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Towards a Viable Hydrogen Storage System for Transportation Application.
Authors: Luo W. , Roennebro E.
Published: February 2006

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Synthesis of the Nanocrystalline MgS and Its Interaction with Hydrogen.
Authors: Goo N. H. , Hirscher M.
Published: February 2006

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
New Metal Iodates: Syntheses, Structures, and Characterizations of Noncentrosymmetric La(IO3)3 and NaYI4O12 and Centrosymmetric β‐Cs2I4O11 and Rb2I6O15 (OH)2×H2O.
Authors: Ok Kang Min , Halasyamani P. Shiv
Published: February 2006

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
High‐Pressure Synthesis of Novel Hydride in Mg—M Systems (M: Li, Pd).
Authors: Goto Y. , Kakuta H. , Kamegawa A. , Takamura H. , Okada M.
Published: February 2006

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Enantiodiscrimination and Enantiocontrol of Neutral and Cationic PtII Complexes Bearing the Tropos Biphep Ligand: Application to Asymmetric Lewis Acid Catalysis.
Authors: Mikami Koichi , Kakuno Hitomi , Aikawa Kohsuke
Published: February 2006

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Synthesis of New Chiral [2‐(1‐Hydroxyalkyl)pyrrolidino]methylferrocenes and Application to the Catalytic Asymmetric Addition of Diethylzinc to Arylaldehydes.
Authors: Xu Cui‐Lian , Wang Min‐Can , Hou Xue‐Hui , Liu Hong‐Min , Wang De‐Kun
Published: February 2006

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Synthesis of P‐Chirogenic Diarylphosphinoacetic Acids and Their Proline Derivatives for Palladium‐Catalyzed Allylic Alkylation Reactions.
Authors: Lam Hubert , Horton Peter N. , Hursthouse Michael B. , Aldous David J. , Hii King Kuok
Published: February 2006

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Ring Opening Reaction of Epoxides under Aryl Acetylene/ZnBr2/DIEA Conditions.
Authors: Lee Ka Young , Park Da Yeon , Kim Taek Hyeon , Kim Jae Nyoung
Published: February 2006

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Palladium‐Mediated Transannular Cyclizations of Medium‐Ring Olefinic Enolsilanes.
Authors: Kende Andrew S. , Nelson Clara E. Mota , Fuchs Sebastien
Published: February 2006

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Co‐Immobilized Formate Anion and Palladium on a Polymer Surface: A Novel Heterogeneous Combination for Transfer Hydrogenation.
Authors: Basu Basudeb , Das Sajal , Das Pralay , Nanda Ashish K.
Published: February 2006

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
A Novel cis‐Chelated Pd(II)—NHC Complex for Catalyzing Suzuki and Heck‐Type Cross‐Coupling Reactions.
Authors: Xu Qin , Duan Wei‐Liang , Lei Zhi‐Yu , Zhu Zhi‐Bin , Shi Min
Published: February 2006

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Baylis—Hillman Reactions in Aqueous Acidic Media.
Authors: Caumul Prakashanand , Hailes Helen C.
Published: February 2006

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Synthesis of Acetylenic Ketones by a Pd‐Catalyzed Carbonylative Three‐Component Coupling Reaction in [bmim]PF6.
Authors: Fukuyama Takahide , Yamaura Ryo , Ryu Ilhyong
Published: February 2006

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Highly Efficient Nitration of Phenolic Compounds in Solid Phase or Solution Using Bi(NO3)3×5H2O as Nitrating Reagent.
Authors: Sun Hong‐Bin , Hua Ruimao , Yin Yingwu
Published: February 2006

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Palladium‐Catalyzed Conversion of Benzylic and Allylic Halides into α‐Aryl and β,γ‐Unsaturated Tertiary Amides by the Use of a Carbamoylsilane.
Authors: Cunico Robert F. , Pandey Rajesh K.
Published: February 2006

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
BiCl3 Catalyzed Thiolyzation Reaction of 1,2‐Epoxides with Diaryl Disulfides in the Presence of Zinc Powder and Ionic Liquid.
Authors: Khosropour A. R. , Khodaei M. M. , Ghozati K.
Published: February 2006

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Silver‐Catalyzed Imination of Sulfoxides and Sulfides.
Authors: Cho Gae Young , Bolm Carsten
Published: February 2006

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
A New One‐Pot Synthesis of Thiocarbamates from Isocyanates and Disulfides in the Presence of Zn/AlCl3 System.
Authors: Movassagh Barahman , Zakinezhad Yousef
Published: February 2006

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Novel Steroid Mimics Directed Towards the Estradiol Skeleton.
Authors: Bridgeman Eve , Cavill Julie L. , Schofield Daniel J. , Wilkins Derek S. , Tomkinson Nicholas C. O.
Published: February 2006

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Arylzinc Species by Microwave Assisted Grignard Formation—Transmetalation Sequence: Application in the Negishi Coupling.
Authors: Mutule Ilga , Suna Edgars
Published: February 2006

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Palladium‐Catalyzed Cross‐Coupling of B‐Benzyl‐9‐borabicyclo[3.3.1]nonane to Furnish Methylene‐Linked Biaryls.
Authors: Flaherty Alice , Trunkfield Amy , Barton William
Published: February 2006

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Synthetic Approach to Enyne and Enediyne Analogues of Anticancer Agents.
Authors: Provot Olivier , Giraud Anne , Peyrat Jean‐Francois , Alami Mouad , Brion Jean‐Daniel
Published: February 2006

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Cyclization of 1‐Phenyl‐2‐propen‐1‐ones into 1‐Indanones Using H‐Zeolite and Other Solid Acids. The Role of Mono‐ and Dicationic Intermediates.
Authors: Koltunov Konstantin Yu. , Walspurger Stephane , Sommer Jean
Published: February 2006

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Reactions of 2‐(α‐Haloalkyl)thiiranes with Nucleophilic Reagents. Part 4. Alkylation of Sulfonamides with 2‐Chloromethylthiirane. Synthesis and Properties of 3‐(Arylamino)thietanes.
Authors: Sokolov V. V. , Butkevich A. N. , Yuskovets V. N. , Tomashevskii A. A. , Potekhin A. A.
Published: February 2006

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Pyrene‐benzoylthiophene Bichromophores as Selective Triplet Photosensitizers.
Authors: Perez‐Prieto Julia , Perez Lourdes Pastor , Gonzalez‐Bejar Maria , Miranda Miguel A. , Stiriba Salah‐Eddine
Published: February 2006

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.