bluuebunny/crossref_metadata_2025 huggingface dataset:
Lead
Authors: Goyer Robert A.
Published: August 2005

Lead is an important industrial commodity. Historically, it has had more uses than any other metal. The mining of lead‐containing ores began in antiquity as mentioned in the Old Testament. It was used in ancient Egypt in coins, weights, ornaments, utensils, ceramic glazes, and solder. The Romans also found many uses for lead, including conduits for drinking water, which probably contributed to excessive lead exposure for the general population. Although descriptions of the toxic effects of lead appeared very early in history, the association between the use of lead in industry and health effects was very slow to evolve. The descriptions provided by the early observations of physicians such as Tanquerel des Planches and Thomas Oliver are milestones in the recognition of the multiorgan effects of lead. Insights into mechanisms did not appear until the twentieth century in parallel with the broader understanding of human biology and the emergence of the practice of medicine as a science. For example, the review by Aub provides early insights into mechanisms of lead toxicity particularly the role of bone in lead metabolism. Over the next two decades the correlation between pathological and clinical effects of lead on organ systems were better defined, as was the significance of specific ranges of blood lead levels. A concise overview of the status of the toxicology of lead for some 30 years is contained in Ethyl Browning's monograph on the toxicity of industrial metals. Considerably more information is available now. One cannot help but be amazed at the continuing flow of reports in the scientific literature to this day regarding effects of lead at the cellular and molecular levels. This allows for more precise interpretation of relationships between exposure and effect. These few historic references provide perspective and appreciation for the evolution of present‐day concerns and workplace practices regarding lead.

The objective of this chapter is to integrate the emerging scientific advances in the toxicology of lead with the occurrence and recognition of clinical effects. A list of current publications regarding health criteria and protective regulatory measures for exposure to lead in the community and workplace is also provided.
Titanium, Zirconium, and Hafnium
Authors: Murthy Leela I. , Dankovic David A. , Murthy Raman C.
Published: August 2005

Titanium, zirconium, and hafnium belong to the transition Group IV B elements of the periodic table. A characteristic feature of these transition elements is the ease with which they form stable complex ions. Features that contribute to this ability are favorably high charge‐to‐radius ratios and the availability of unfilleddorbitals. The facility in forming metallic bonds is demonstrated by the existence of a wide variety of alloys among different transition metals. Another feature of these metals is characterized by their high densities, high melting points, and low vapor pressures. Within this group, these properties tend to increase with increasing atomic weight.

This chapter discusses the chemical and physical properties followed by the toxicity of each chemical and compound in three sections: Section A provides details on titanium, Section B on zirconium, and Section C on hafnium. Tables present the atomic number, atomic weight, and natural isotopes of titanium, zirconium, and hafnium.
Aliphatic Nitro, Nitrate, And Nitrite Compounds
Authors: Doepker Candace Lippoli
Published: August 2005

Although aliphatic nitro compounds, aliphatic nitrates, and aliphatic nitrites have several features in common (nitrogen‐oxygen grouping, explosiveness, methemoglobin formation), there are significant differences in their toxic effects. Some of their attributes are summarized. The esters of nitric and nitrous acid, whose nitrogen is linked to carbon through oxygen, are very similar in their pharmacological effects. Both produce methemoglobinemia and vascular dilatation with hypotension and headache. These effects are transient. None of the series has appreciable irritant properties. Pathological changes occur in animals only after high levels of exposure and are generally nonspecific and reversible. The nitric acid esters of the monofunctional and lower polyfunctional alcohols are absorbed through the skin. Information is not available on the skin absorption of alkyl nitrites. Members of both groups are well absorbed from the mucous membranes and lungs. Heinz body formation has been observed with the nitrates but not with the nitrites.

Nitro compounds, like nitrates and nitrites, cause methemoglobinemia in animals. Heinz body formation parallels this activity within the series. Although some members are metabolized to nitrate and nitrite, there is no significant effect on blood pressure or respiration. As with the lower nitrates and nitrites, anesthetic symptoms are observed in animals during acute exposures, but these occur late. The prominent effect is irritation of the skin, mucous membranes, and respiratory tract. This is most marked with chlorinated nitroparaffins and nitroolefins. In addition to respiratory tract injury, cellular damage may be observed in the liver and kidneys. Skin absorption is negligible except for the nitroolefins.

The nitramines have entirely different activity. RDX is a convulsant for humans and animals. Skin absorption, irritation, vasodilatation, methemoglobin formation, and permanent pathological damage are either insignificant or absent after repeated doses.

Transient illness has been associated with the industrial use or manufacture of these materials, but fatalities and chronic intoxication have been uncommon. Some members of each group present extremely high fire and explosion hazards.
Aromatic Amino and Nitro–Amino Compounds and their Halogenated Derivatives
Authors: Woo Yin-Tak , Lai David Y.
Published: August 2005

Aromatic amines are organic compounds that contain at least one amino group attached directly to an aryl moiety. Aromatic amines represent one of the most important classes of industrial and environmental chemicals. Many aromatic amines have been shown to be potent carcinogens and mutagens and/or hemotoxicants capable of inducing methemoglobinemia. Since the introduction of substituted anilines and naphthylamines as intermediates for the manufacture of azo dyes in the mid‐1800s, aromatic amines have found numerous uses in various industries. Substantial worker exposure to aromatic amines with subsequent induction of bladder cancer occurred before preventive measures were instituted. Beyond occupational exposure, humans may also be exposed to aromatic amines through environmental sources. At least three carcinogenic aromatic amines (4‐aminobiphenyl, 2‐naphthylamine, ando‐toludine) have been detected in cigarette smoke. Many commonly used pharmaceuticals contain or are aromatic amines. Owing to their hazard potential, aromatic amines have been the subject of many biomonitoring studies, making them model compounds in molecular dosimetry and epidemiology studies. Since extensive information is available on the metabolic pathways and, to a lesser extent, the mechanism(s) of action, aromatic amines have also become targets for genetic polymorphism studies with ultimate goals of identifying susceptible subpopulations, and designing of strategies for cancer prevention and intervention. The multifaceted interest in aromatic amines has continued to attract a tremendous amount of scientific studies and attention. Since the publication of the previous edition of Patty's on aromatic amines, many reviews and important research articles on aromatic amines have been published. In this chapter, we present an overview of the aromatic amine class as a whole with emphasis on recent studies, followed by an updated description on individual chemicals grouped into seven subgroups of structurally related compounds.
Aliphatic Carboxylic Acids, Saturated
Authors: Cragg Steven T.
Published: August 2005

Aliphatic carboxylic acids include a very wide range of chemicals that perform a diverse range of industrial functions. Many occur naturally and serve an important function in nutrition, and many are intermediates in normal biochemical processes. This chapter is limited to a discussion of the saturated aliphatic mono‐ and polycarboxylic acids. Because of the wide range of uses, the differing circumstances of isolation, and frequently the complexity of structure, many organic acids are described by a variety of names. In this chapter the names used in the text are usually the trivial or most common names; alternative names are given for reference. A current systematic or Chemical Abstracts acid name is given in the tables that describe physicochemical properties. The commercial and industrial importance of this class of compounds is indicated by recent production figures: acetic acid has a production volume in the region of 3.3 billion lb/year, acrylic acid in excess of 1 billion lb/year, and propionic acid of the order of 100 million lb/year. Esters and salts of organic acids are also produced in large volume.

In general, serious physiological concerns for humans do not arise from the acids discussed in this chapter. Occasionally, concerns have been reported for individual acids, but usually with very high experimental or accidental exposures. The low level of concern associated with most of these acids is attested to by the many members of this class that are used as food additives, flavoring agents, and stabilizers, or as food materials. The primary adverse effect of exposure to aliphatic carboxylic acids is usually acute arising from their primary irritant effects on skin, eyes, and mucous membranes, particularly of the short‐chain acids. As the molecular weight increases and the water solubility decreases, the irritating capacity of a carboxylic acid generally decreases. In addition, skin sensitization is quite rare with the aliphatic carboxylic acids.
Aliphatic Carboxylic Acids, Unsaturated
Authors: Cragg Steven T.
Published: August 2005

The alkenoic series of carboxylic acids are obtained from such natural sources as animal tallows and greases, and vegetable, coconut, palm, and marine oils. Several have also been produced synthetically from petroleum sources. They are frequently referred to as fatty acids (C6to C24) and have important commercial applications in plastics, coating materials, fungicides, food preservatives, lubricants, and perfumes. They have been used as softening agents for rubber and as pharmaceuticals in medicine and dentistry. Acids of this type are unstable and polymerize readily, hence offering important chemical and physical properties for use in producing esters, acid halides, acid amides, and acid anhydrides.

As a class, the unsaturated carboxylic acids have been subjected to an extensive battery of studies, including acute, short‐term, and chronic toxicity and carcinogenicity tests and reproductive and developmental toxicity and genotoxicity tests. Overall, these acids have a low level of mammalian toxicity, although they are strong skin and eye irritants in animal tests and are irritating to mucosal membranes in humans. For those acids for which adequate studies have been conducted, there is no evidence that they are reproductive or developmental toxicants or carcinogens. Mutagenicity and clastogenicity studies suggest that this group of acids is devoid of genotoxic activity. The biochemistry of many of these acids can be found in general textbooks. Rapid metabolism to other fatty acids may explain their general low degree of toxicity. The physical properties and acute toxicity of saturated monocarboxylic acids are provided.
Glycols
Authors: Cavender Finis L. , Sowinski Edward J.
Published: August 2005

The glycols are hydrocarbons that have two hydroxyl groups attached to separate carbons in an aliphatic chain or alicyclic ring. They are used as antifreeze agents, cryoprotectants, solvent carriers, chemical intermediates, and vehicles in a number of chemical formulations. They vary from slightly viscous liquids to waxy solids, are soluble in water, alcohols, and ketones, and are insoluble in hydrocarbons.

They have low vapor pressures; therefore inhalation of vapors and aerosols is of little concern unless they are heated, agitated, or sprayed. They have little or no odor; thus only their irritancy at high concentrations is a warning property.

Because of the irritant properties and the potential for central nervous system (CNS) depression at high concentrations, the threshold limit value (TLV) for glycols is generally set as a ceiling limit. The chemical and physical properties of several of the more common glycols are given.
Polyurethanes, Miscellaneous Organic Polymers, and Silicones
Authors: Cragg Steven T.
Published: August 2005

The toxicity of the polymers discussed in this chapter may be generally attributed to the residual monomers, catalysts, and other additives present rather than the polymerper se. The cured polymer itself may be of high molecular weight and, consequently, more or less toxicologically inert. Carefully manufactured, highly refined polymers contain few residual toxic chemicals. However, some of the polymers discussed in this chapter, at least in some applications, go through an intermediate stage consisting of “prepolymers” (sometimes referred to as “resins”) that react further to achieve their final, cured form. An example is a polyurethane system for making foam cushions. To manufacture polyurethane foam for cushions, workers combine diisocyanate molecules with a polyol prepolymer. Such “systems” inherently have more potential for exposure of workers if not the general public to toxic monomers or other reactive chemicals. The exposure potential of glues, paints, and coatings may extend more broadly to the consumer. Thus, examination of the toxicity of the polymers discussed in this chapter focuses on monomers and prepolymers. This is not always so. Some of polymers in this chapter are used in biomedical devices or in a way that puts them in intimate contact with humans. Here, the issue of biodegradation becomes important because of potential toxicity from breakdown products of the polymer, or rejection may ensue if the polymer is incompatible with the surrounding tissues.
Organophosphorus Compounds
Authors: Storm Jan E.
Published: August 2005

Organophosphate pesticides are a highly diverse group of chemicals to which workers may be exposed during manufacture and formulation and during or after application for their intended uses. They are all characterized by their ability to inhibit the enzyme acetylcholinesterase (AChE) that deactivates the neurotransmitter acetylcholine (ACh).

Compounds in this class are numerous and have been categorized in many ways according to the nature of the substituents. Gallo and Lawryk, for example, categorized them into four main categories (Groups I‐IV) based on the characteristics of the leaving group (X). Group I compounds, phosphorylcholines, have a leaving group that contains a quaternary nitrogen and are among the most potent organophosphates (e.g., Shradan). Group II compounds, fluorophosphates, have a fluoride leaving group and are also generally highly toxic (e.g., diisopropyl fluorophosphate). Group III compounds have leaving groups that contain cyanide or a halogen other than fluoride and are generally less potent than Groups I or II (e.g., Parathion). Group IV contains most of the organophosphates used as insecticides today. These compounds have alkoxy, alkylthio, aryloxy, arylthio or heterocyclic leaving groups and a wide variety of other substituents.

Another classification scheme is based on the nature of the atoms that immediately surround the central phosphorus atom and results in 14 different categories. According to this scheme, phosphates are the prototype for the entire class and are those compounds where all four atoms that surround the phosphorus atom are oxygen (e.g., dichlorvos, mevinphos). Sulfur‐containing organophosphate compounds (phosphorothioates; phosphorothiolates; phosphorodithioates; phosphorodithiolates) are far more numerous than phosphates and include well recognized organophosphate insecticides such as parathion, diazinon, chlorpyrifos, etc. Other groups contain nitrogen (phosphoramides and phosphorodiamides), nitrogen and sulfur (phosphoramidothionates and phosphoramidothiolates), carbon (phosphonates and phosphinates), or carbon and sulfur (phosphonothionates, phosphonothionothiolates and phosphinothionates).

All aspects of organophosphate chemistry, toxicity, analysis, and exposure potential have been previously reviewed. Additionally information regarding the toxicity of this class of compounds has expanded greatly in recent years as a result of toxicity data supplied by registrants to the U.S. EPA's Office of Pesticides to support reregistration. These data are being made publically available by the U.S. EPA on their internet web site. The following discussion draws heavily from recent reviews but also includes summaries of relevant toxicity data submitted to the U.S. EPA available when this chapter was completed. Due to space limitations detailed data reviews are included here for only 30 organophosphate pesticides. Information on other pesticides registered or undergoing reregistration in the United States can be readily obtained from the previously mentioned website.
Occupational Ergonomics: Principles and Applications
Authors: Bhattacharya Amit , Talbott Nancy , Kincl Laurel
Published: August 2005

This chapter provides the basic principles that underlie the field of ergonomics and their application to some of the current issues of importance in the workplace. Sections 2 to 4 deal with the physiology of muscles; biomechanics; cellular responses to tissue, nerve, and joint injuries as they relate to cumulative trauma disorders; and common types of overuse syndromes. The remaining sections deal with applications of the principles to workplace ergonomic issues and proposed ergonomic regulations.

The word “ergonomics” is made up of two Greek words, “ergo” meaning work and “nomas” meaning laws. The field of ergonomics is highly interdisciplinary. It applies principles from engineering, physiology, medicine, and psychology to the understanding of the interaction of humans with their workplace. The interaction of humans with their workplace may consist of identifying the relationship between job physical risk factors and physiological responses. For example, a specific ergonomic problem of paramount importance in the occupational health and safety is the issue of work‐related musculoskeletal disorders (WMD). Some of these issues are discussed further in this chapter. The specific areas of application relevant for the field of ergonomics are defined and briefly explained.

Activities that involve repetitive stress have effects that are extremely complicated. Adding internal or external forces to the body can, as described, alter bone, joints, ligaments, tendons, nerves, and muscles. Belief that a repetitive motion will result in an isolated nerve injury without affecting surrounding joints, ligaments, muscles, or tendons is likely to inhibit appropriate care and control of exposed individuals. Additional research is needed to further characterize changes that occur, and current approaches to recognizing, managing and preventing repetitive injuries must address all tissues in the involved area.
Flavorings
Authors: Lippmann Morton
Published: August 2005

In the past several years, chemicals used to flavor foods, flavorings, have been observed to cause varying health effects. A number of these chemicals have already been discussed in sections of other chapters. As a beginning to this chapter, a table is provided which lists the names of the chemicals, their CAS number, synonyms for the chemical and where in previous chapters toxicologic information about them can be found.
Isocytosine as a Hydrogen‐Bonding Partner and as a Ligand in Metal Complexes
Authors: Gupta Deepali , Roitzsch Michael , Lippert Bernhard
Published: August 2005

Isocytosine (ICH; 1) exists in solution in an equilibrium of tautomers 1 a and 1 b with the N1 and N3 positions carrying the acidic proton, respectively. In the solid state, both tautomers coexist in a 1:1 ratio. As we show, the N3H tautomer 1 b can selectively be crystallized in the presence of the model nucleobase 1‐methylcytosine (1‐MeC). The complex 1 b⋅(1‐MeC)⋅2 H2O (2) forms pairs through three hydrogen bonds between the components; hydrogen bonds between identical molecules are also formed, leading to an infinite tape structure. On the other hand, the N1H tautomer 1 a co‐crystallizes with protonated ICH to give [1 a⋅ICH2]NO3 (3), again with three hydrogen bonds between the partners, yet the acidic proton is disordered over the two entities. With MII(dien) (M=Pt, Pd; dien=diethylenetriamine) preferential coordination of tautomer 1 a through the N3 position is observed. DFT calculations, which were also extended to PtII(tmeda) linkage isomers (tmeda=N,N,N′,N′‐tetramethylethylenediamine), suggest that intramolecular hydrogen bonding between the ICH tautomers and the co‐ligands at M, while adding to the preference for N3 coordination, is not the major determining factor. Rather it is the inherently stronger PtN3 bond which favors complexation of 1 a. With an excess of MII(dien), dinuclear species [M2(dien)2(IC‐N1,N3)]3+ (M=PdII, 4 and PtII, 5) also form and were isolated as their ClO4− salts and structurally characterized. In strongly acidic medium 5 is converted to [Pt(dien)(ICH‐N1)]2+ (6), that is, to the PtII complex of tautomer 1 b.
Zoledronic acid inhibits primary bone tumor growth in Ewing sarcoma
Authors: Zhou Zhichao , Guan Hui , Duan Xiaoping , Kleinerman Eugenie S.
Published: August 2005

BACKGROUND

Zoledronic acid has been shown to be effective in the treatment of osteoporosis, hypercalcemia, and metastatic bone tumors. The efficacy of zoledronic acid on primary bone tumors has not been investigated.

METHODS

A primary bone tumor mouse model was established. Intratibia injection of TC71 cells resulted in an osteolytic bone tumor. Four days after injection the mice were treated with zoledronic acid alone, paclitaxel alone, or zoledronic acid plus paclitaxel. Control mice were treated with phosphate‐buffered saline. Bone tumor growth was assessed using a Faxitron Specimen Radiography System. The gene expression was detected by reverse‐transcription polymerase chain reaction (RT‐PCR), ELISA, and immunohistochemistry. Osteoclast formation was determined by tartrate‐resistant acid phosphatase (TRAP) staining.

RESULTS

Zoledronic acid induced apoptosis in TC71 human Ewing sarcoma cells and inhibited cell proliferation. Five weeks after injection, 89% of mice in the control group developed osteolytic bone tumors. Paclitaxel had little effect on bone tumor growth, with 78% of mice developing tumors. By contrast, 44% of mice treated with zoledronic acid developed bone tumors. The most effective treatment was zoledronic acid plus paclitaxel. Tumor incidence in the combination therapy group was only 22%. Osteoclasts were quantified using TRAP staining. There was a decrease in TRAP‐positive osteoclasts in tumor tissues from zoledronic acid‐treated animals compared to control animals. RT‐PCR, immunohistochemistry, and ELISA assay demonstrated that zoledronic acid up‐regulated osteoprotegerin expression.

CONCLUSIONS

These results suggest that zoledronic acid induces apoptosis and inhibits primary bone tumor growth in Ewing sarcoma through a mechanism involving the up‐regulation of osteoprotegerin. Zoledronic acid may provide a novel therapeutic approach for the treatment of patients with Ewing sarcoma. Cancer 2005. © 2005 American Cancer Society.
Homocysteine inhibits extra‐embryonic vascular development in the avian embryo
Authors: Latacha Kimberly S. , Rosenquist Thomas H.
Published: August 2005

A strong association exists between pregnancy loss and maternal elevations of the sulfur‐containing amino acid, homocysteine. Because extra‐embryonic vascular growth is critical to maintaining a normal pregnancy, we examined the effects of homocysteine on vessel development by exposing avian embryos to exogenous homocysteine during critical periods of vascular growth. These experiments demonstrated that homocysteine significantly reduced survival and decreased angiogenesis in the extra‐embryonic vasculature. Homocysteine was also found to reduce mRNA and protein expression of vascular endothelial growth factor (VEGF), a key molecule for vascular development. Moreover, in cultured human umbilical vein endothelial cells, homocysteine increased the synthesis of nitric oxide, an important regulatory molecule for VEGF. Inhibiting the homocysteine‐induced up‐regulation of nitric oxide restored normal VEGF expression and vascular development. These results suggest that homocysteine may impair the development of the extra‐embryonic vasculature by reducing the expression of VEGF. Developmental Dynamics 234:323–331, 2005. © 2005 Wiley‐Liss, Inc.
Motor‐related cortical dynamics to intact movements in tetraplegics as revealed by high‐resolution EEG
Authors: Mattia Donatella , Cincotti Febo , Mattiocco Marco , Scivoletto Giorgio , Marciani Maria Grazia , Babiloni Fabio
Published: August 2005

We explored the cortical dynamics during movements of an unaffected body part in tetraplegic subjects with chronic spinal cord injury (SCI). The aims were to find out whether the intact movements were associated with a physiological time‐varying pattern of activity in the motor‐related cortical areas and whether the primary motor area (MI) activation followed a somatotopic distribution. Event‐related potentials to self‐initiated lip movements were analyzed by means of cortical source imaging of EEG recorded from seven tetraplegic subjects and seven control subjects. Regions of interest (ROIs) were selected on individual MRI and the time‐varying electrophysiologic activity (cortical current density, CCD) was estimated on these ROIs and subjected to across‐subject analysis. A significant, bilateral movement‐related pattern of MI activation was detected during motor task execution in SCI patients as well as in controls. The site of local maxima activation displayed a symmetrical discrete distribution within MI, consistently with a putative somatotopic lip representation, in all the subjects. The supplementary motor area proper (SMAp) was always coactivated with MI and coactivation was characterized by a time course with typical premotion and motion phases over both motor areas. A clear‐cut temporal delay between the SMAp and MI activation did not occur either in SCI patients or in controls. These findings obtained with noninvasive neuroelectrical source imaging document that in chronic SCI subjects “executive” motor areas are engaged with a preserved temporal and spatial pattern during preparation and execution of intact movements. Hum Brain Mapp, 2005. © 2005 Wiley‐Liss, Inc.
Sensorimotor organization in double cortex syndrome
Authors: Jirsch Jeffrey D. , Bernasconi Neda , Villani Flavio , Vitali Paolo , Avanzini Giuliano , Bernasconi Andrea
Published: August 2005

Subcortical band heterotopia is a diffuse malformation of cortical development related to pharmacologically intractable epilepsy. On magnetic resonance imaging (MRI), patients with “double cortex” syndrome (DCS) present with a band of heterotopic gray matter separated from the overlying cortex by a layer of white matter. The function and connectivity of the subcortical heterotopic band in humans is only partially understood. We studied six DCS patients with bilateral subcortical band heterotopias and six healthy controls using functional MRI (fMRI). In controls, simple motor task elicited contralateral activation of the primary motor cortex (M1) and ipsilateral activation of the cerebellum and left supplementary motor area (SMA). All DCS patients showed task‐related contralateral activation of both M1 and the underlying heterotopic band. Ipsilateral motor activation was seen in 4/6 DCS patients. Furthermore, there were additional activations of nonprimary normotopic cortical areas. The sensory stimulus resulted in activation of the contralateral primary sensory cortex (SI) and the thalamus in all healthy subjects. The left sensory task also induced a contralateral activation of the insular cortex. Sensory activation of the contralateral SI was seen in all DCS patients and secondary somatosensory areas in 5/6. The heterotopic band beneath SI became activated in 3/6 DCS patients. Activations were also seen in subcortical structures for both paradigms. In DCS, motor and sensory tasks induce an activation of the subcortical heterotopic band. The recruitment of bilateral primary areas and higher‐order association normotopic cortices indicates the need for a widespread network to perform simple tasks. Hum Brain Mapp, 2005. © 2005 Wiley‐Liss, Inc.
Influence of surface self‐modification in Ringer's solution on the passive behavior of titanium
Authors: Alkhateeb E. , Virtanen S.
Published: August 2005

The influence of the spontaneous surface modification of titanium by exposure to Ringer's solution at open‐circuit conditions on the passive behavior was studied. The electrochemical behavior of Ti was compared in a simple NaCl and in Ringer's physiological solution. Potentiodynamic polarization curves show significantly higher passive current densities in Ringer's solution as compared with the simple saline solution. Furthermore, impedance spectra measured at the open‐circuit potential as a function of time indicate that in saline solution a long‐term exposure over some days leads to a strong increase of the protectiveness of the passive film. This improvement of the passive behavior cannot be observed in Ringer's solution, but a strong modification of the passive film/electrolyte interface can be seen in the impedance spectra. The changes in the impedance spectra can be correlated with the results observed by surface characterization regarding the morphology (scanning electron microscopy) and chemical composition of the surface (X‐ray photoelectron spectroscopy). In agreement with previous work by others, a spontaneous modification of the surface of Ti by Ca and P species was observed. The composition of the Ca/P precipitates changes as a function of time, indicating a slow formation of a hydroxyapatite‐like deposit layer on the surface. The results of the present work indicate that the formation of the outer Ca‐P deposit layer on the passive Ti surface (which is beneficial for the biological performance) hinders the normal aging of the passive TiO2. Even though the protectiveness of the passive film can be considered as high also in Ringer's solution, significantly higher passive dissolution rates (i.e., higher metal‐ion release) for Ti exposed to Ringer's solution can be expected as compared with a simple saline solution. © 2005 Wiley Periodicals, Inc. J Biomed Mater Res, 2005
Occipito‐vertebral fusion in ocean sunfishes (Teleostei: Tetraodontiformes: Molidae) and its phylogenetic implications
Authors: Britz Ralf , Johnson G. David
Published: August 2005

We describe the ontogeny of the occipital skull and anterior vertebrae of the molidsRanzania laevisandMasturus lanceolatusand compare it with that of the ostraciidLactophryssp. The first vertebra fuses to the basioccipital in early ontogeny in the two molids and previous authors thus confused that vertebra with the back of the basioccipital, so that all previous counts of their vertebral numbers are incorrect by one vertebra. As evidenced byLactophryssp., ostraciids are the only other tetraodontiforms with similar occipito‐vertebral fusion. In contrast to the molids, additional anterior vertebrae fuse with this complex in ostraciids. We conclude that the shared occipito‐vertebral fusion in molids and ostraciids and its otherwise extremely rare occurrence among teleosts provide support for a sister‐group relationship of the two families. J. Morphol. © 2005 Wiley‐Liss, Inc.
Polyphenol oxidase/caffeic acid may reduce the allergenic properties of peanut allergens
Authors: Chung Si‐Yin , Kato Yoji , Champagne Elaine T
Published: August 2005

Polyphenol oxidase (PPO) catalyzes the oxidation of tyrosine residues of proteins and, therefore, their cross‐linking. Previously we demonstrated that cross‐links produced by peroxidase (POD), which also catalyzes tyrosine oxidation, led to a reduction in the allergenic properties of peanut allergens.11 We postulated in this study that PPO can also reduce the allergenic properties by cross‐linking the allergens. Because caffeic acid, a phenolic compound, can cross‐link proteins, its effect on peanut allergens was also examined. In the experiments, peanut extracts were treated with and without PPO, PPO/caffeic (pH 8, 37 °C for 1 h) and caffeic acid (pH 10.5, overnight), respectively. The samples were then analyzed for cross‐links and IgE binding by SDS‐PAGE, Western blots, and competitive inhibition ELISA. Results showed that, in all cases, cross‐links and a decrease of the levels of two peanut major allergens, Ara h 1 and Ara h 2, were observed. Of the three treatments, PPO/caffeic was the most effective in reducing IgE binding or the allergenic properties of peanut allergens. The availability of tyrosine residues was also demonstrated in a POD‐treated system, using a monoclonal antibody against dityrosine. We concluded that PPO/caffeic acid reduced the allergenic properties of Ara h 1 and Ara h 2 by cross‐linking and decreasing the levels of allergens. Copyright © 2005 Society of Chemical Industry
In vitro accessibility of β‐carotene from cooked Sri Lankan green leafy vegetables and their estimated contribution to vitamin A requirement
Authors: Chandrika U Gamage , Svanberg Ulf , Jansz Errol R
Published: August 2005

Vitamin A deficiency is an important issue for public health in Sri Lanka, where pro‐vitamin A carotenoids from green leafy vegetables provide most of the dietary vitamin A. The objective of this study was to analyse the β‐carotene content of seven types of green leafy vegetables and calculate the contribution of one traditionally cooked portion to the recommended daily allowance (RDA) of retinol. The total amount and in vitro accessibility of β‐carotene were determined using HPLC. The in vitro method simulates the conditions in the human intestinal tract. The all‐trans‐β‐carotene content in the fresh blanched vegetables ranged from 149 µg g−1 dry weight (DW) in leaves of Alternanthera sessilis (mukunuwanna) to 565 µg g−1 DW in Amaranthus caudatus (thampala). One portion (100 g) of green leaves cooked without fat (coconut) only contributed from 140 to 180 µg mg−1 of the recommended daily allowance. A. sessilis, Centella asiatica (gotukola), Spinacea oleracea (nivithi) and A. caudatus, cooked with coconut fat contributed 140–680 µg mg−1. However, stir‐fried or ‘malluma’ preparations (with coconut products) of Sesbania grandiflora (kathurumurunga) and Manihot esculenta (manioc) may provide more than 1.59–4.37 times the RDA of retinol. These results show that not only the choice of green leaves used but also the addition of fat while cooking is of great importance. Copyright © 2005 Society of Chemical Industry
Seasonal patterns of sucrose concentration in relation to other quality parameters of sugar beet (Beta vulgaris L.)
Authors: Kenter Christine , Hoffmann Christa M
Published: August 2005

The chemical composition of sugar beet is the most important parameter affecting its processing. Sugar factories require beet with high concentrations of sucrose and low concentrations of melassigenic substances to maximise the amount of extractable sugar. In order to plan the processing campaign, forecasts of root and sugar yield by prediction models are possible but there are no means to predict the technical quality of the beet. In the present study, the seasonal development and physiological relationships of different parameters of sugar beet quality were analysed. In order to estimate possibilities for quality forecasts, the concentrations of beet quality variables in October were correlated with corresponding quality measurements in late summer and to weather variables during the growing season by linear regressions. In 2000 and 2001, 27 field trials were conducted on commercial farm fields in all sugar beet growing areas in Germany. From June to October, sequential samples were taken every 4 weeks and the concentrations of sucrose, potassium, sodium, total soluble nitrogen, α‐amino nitrogen, nitrate, betaine, reducing sugars and marc in the beet were determined. The sucrose concentration increased progressively until the final harvest date in autumn, whereas the concentrations of the melassigenic substances decreased markedly until late summer and remained fairly constant as the season progressed. Marc concentration was the most stable of the parameters analysed. The sucrose concentration was positively correlated with the concentrations of dry matter, betaine and marc, but negatively with nitrate concentration and leaf yield throughout the season. The correlation between the concentrations of sucrose and nitrogenous compounds measured in summer and their final concentrations in autumn was rather weak. However, it was close for potassium, sodium and marc and a satisfactory prediction of their final concentrations was possible by the end of August. Based on weather data, beet quality was not predictable. Therefore, it seems to be difficult to integrate beet quality parameters into prediction models. Copyright © 2005 Society of Chemical Industry
Effect of postharvest handling on valerenic acids content of fresh valerian (Valeriana officinalis) root
Authors: Shohet Deborah , Wills Ron BH
Published: August 2005

Valerian (Valeriana officinalis) is a medicinal herb native to Europe and North Asia, the roots and rhizomes of which are used as a sedative for nervous tension, sleeplessness, anxiety and stress. The impact of washing and drying on the valerenic acids concentration in valerian roots was investigated. The valerenic acids content of roots that were washed, soaked or cut prior to drying was not significantly different from that of whole valerian roots that were dried without washing, but cutting markedly decreased the drying time. Increasing the drying temperature from 15 to 70 °C reduced drying time by 176 h, with a 23% loss of valerenic acids from 15 to 40 °C. A further 36% loss occurred from 40 to 50 °C but no further significant change was evident at higher temperatures. The use of a heat pump dryer reduced the drying time at 40 °C by 25% compared with a hot air drier operated at the same temperature with no significant difference in the level of valerenic acids. There was no significant change in the level of valerenic acids in fresh whole roots held at ambient conditions for 10 days but a considerable decrease in water content. Hence valerian growers can separate or soak roots prior to washing and can store fresh roots before drying without concern over loss of valerenic acids. However, drying at the lowest feasible temperature is recommended. Copyright © 2005 Society of Chemical Industry
Degradation of Poly(lactic acid) into Repolymerizable Oligomer using Montmorillonite K10 for Chemical Recycling
Authors: Okamoto Kohei , Toshima Kazunobu , Matsumura Shuichi
Published: August 2005

Summary: The degradation of poly(L‐lactic acid) (PLLA) into a repolymerizable oligomer was carried out using a clay catalyst, montmorillonite K10 (MK10), with the objective of developing a chemical recycling process. PLLA having an $\overline M _{\rm w}$ of 120 000 was degraded by MK10 in toluene at 100 °C for 6 h to produce the corresponding linear‐type oligomers having a molecular weight of a few hundreds in a yield of greater than 90%. The oligomer was readily polymerized by a conventional chemical catalyst to give a high‐molecular‐weight PLLA. No isomerization of L‐lactic acid occurred during the degradation process using MK10. The MK10 could be repeatedly used at least five times without any significant decrease in its activity. The degradation of PLLA was accelerated by the addition of a small amount of ethanol in toluene using anhydrous MK10 to produce oligomers with ethyl ester end groups.

Degradation of poly(L‐lactic acid) (PLLA) into a repolymerizable oligomer.

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Degradation of poly(L‐lactic acid) (PLLA) into a repolymerizable oligomer.
High‐Content Pendant Photochromic Copolymer with Dithienylethene/Fluorene 2:1 Mole Ratio
Authors: Li Xiaochuan , Tian He
Published: August 2005

Summary: Two photochromic dithienylethene units were incorporated into one fluorene unit as a monomer and the mole ratio of photochromic unit/repeat unit reached to 2:1 using this monomer. The content of dithienylethene component in the polymer could be improved effectively by polymerization of this monomer, which contains more than one dithienylethene units. All the starting materials concerned in the synthesis are commercially available and so the synthesis could be performed on a large scale. The polymer obtained by typical palladium‐catalyzed Suzuki coupling reaction is photochromic both in solution and in solid state and possesses good solubility. The photochromic and photomodulation luminescence properties of the polymer are also presented.

Structure of the photochromic polymer based on dithienylethene.

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Structure of the photochromic polymer based on dithienylethene.
Core complementarities of the corporation: organization of an innovating firm
Authors: Leiponen Aija
Published: August 2005

Despite the proliferation of arrangements to outsource or cooperate in Research and Development, the benefits and costs of alternative organizational forms are not very well understood. This paper develops a supermodularity model to highlight the conditions under which internal or external modes of organizing innovation activities are likely to occur. The technological and institutional environment drives firms' decisions to organize innovation and invest in learning, which determine firm performance in terms of innovation and growth. Internal organization is beneficial when complementarities among activities are strong. However, independent governance of complementary activities may become optimal when depreciation of knowledge is rapid due to radical technical change. Copyright © 2005 John Wiley & Sons, Ltd.
Price‐matching policy with imperfect information
Authors: Mao Wen
Published: August 2005

The model of price‐matching policy emphasizes on the importance of information imperfection. The demand is derived based on the assumptions that consumers have different reservation prices and different preferences over location. When a firm undercuts its competitor's price, it changes the demand structure of the market. The result shows that price‐matching policies are anticompetitive, but they do not facilitate monopoly price. Copyright © 2005 John Wiley & Sons, Ltd.
Technological and organizational changes as determinants of the skill bias: evidence from the Italian machinery industry
Authors: Piva Mariacristina , Santarelli Enrico , Vivarelli Marco
Published: August 2005

Recent empirical literature has introduced the ‘Skill Biased Organizational Change’ (SBOC) hypothesis, according to which organizational change can be considered as one of the main causes of the skill bias (increase in the number of highly skilled workers) exhibited by manufacturing employment in developed countries. This paper focuses on the importance of the SBOC with respect to the more traditional ‘Skill Biased Technological Change’ in driving the skill composition of workers in the Italian machinery sector. A dynamic panel data analysis is proposed which uses a unique firm‐level dataset. The results show that both skilled and unskilled workers are negatively affected by technological change, while organizational change—which in turn may be linked to new technologies—is positively linked to skilled workers. Copyright © 2005 John Wiley & Sons, Ltd.
Evidence for further genetic locus heterogeneity and confirmation of RLS‐1 in restless legs syndrome
Authors: Winkelmann Juliane , Lichtner Peter , Pütz Benno , Trenkwalder Claudia , Hauk Stephanie , Meitinger Thomas , Strom Tim , Muller‐Myhsok Bertram
Published: August 2005

Restless legs syndrome (RLS; MIM 102300) is a common neurological disorder characterized by dysesthesias and an urge to move the lower limbs. The symptoms predominantly occur at rest, in the evening, and improve with movement. There is a high familial aggregation but gene mutations have not yet been found. Three loci for RLS on chromosomes 12q, 14q, and 9p (RLS‐1, RLS‐2, and RLS‐3) have been reported with a recessive (RLS‐1) and autosomal dominant (RLS‐2, RLS‐3) mode of inheritance, respectively. The overall contribution of these loci to this disorder is not known. To evaluate the significance of these loci, we investigated 12 RLS families for possible linkage to these chromosomal regions. Genotyping was carried out in 70 affected family members using 26 polymorphic microsatellite markers (chromosome 12: 7; chromosome 14: 7, chromosome 9: 12). Linkage analysis was carried out using the published parameters applied in the original studies (chromosome 12: q = 0.25, f0 = 0.005, f1 = 0.005, f2 = 0.8; chromosome 14: q = 0.003, f0 = 0.005, f1 = f2 = 0.95; chromosome 9: q = 0.001, f0 = 0.005, f1 = f2 = 0.95; affected individuals only). In addition, transmission disequilibrium test (TDT) analyses were done. We found evidence for linkage on chromosome 12 using the TDT. Linkage to RLS‐2 and RLS‐3 was excluded in 1 of 12 families. This supports the existence of RLS‐1 and provides evidence for the likelihood of further genetic locus heterogeneity of RLS. Investigations in additional RLS families are required to confirm the known loci and further genome wide linkage analyses have the potential to identify additional RLS loci. © 2005 Movement Disorder Society
Syncoilin upregulation in muscle of patients with neuromuscular disease
Authors: Brown Susan C. , Torelli Silvia , Ugo Isabella , De Biasia Floriana , Howman Emily V. , Poon Ellen , Britton Joanna , Davies Kay E. , Muntoni Francesco
Published: August 2005

Syncoilin may have a role in linking the desmin‐associated intermediate filament network of the muscle fiber with the dystrophin‐associated protein complex (DAPC). We have evaluated syncoilin in a range of neuromuscular disorders including Duchenne and Becker muscular dystrophy, central core disease, congenital muscular dystrophies, and neurogenic disorders. Our results show that syncoilin immunolabeling is not only altered in muscle fibers with alterations in the DAPC but also in response to a variety of genetic defects, including those associated with proteins of the extracellular matrix and the intracellular Ca2+‐release channel (ryanodine receptor). The pattern of syncoilin immunolabeling in these diseases appeared to reflect a rearrangement of the intermediate filament–associated cytoskeleton that characterizes both muscle fiber development and conditions in which the cytoskeletal organization of the muscle fiber is significantly affected. These observations raise the possibility that mutations in the gene encoding for syncoilin may underlie some forms of muscle disease. Muscle Nerve, 2005
Successful treatment of pulmonary zygomycosis with posaconazole in a recipient of a haploidentical donor stem cell transplant
Authors: Gilman Andrew L. , Serrano Amy , Skelley John , Zwick David
Published: August 2005

We report the clinical course of a patient who developed a Rhizopus infection of his right lung and pleural cavity, 11 months after receiving a T‐cell‐depleted, haploidentical donor peripheral blood stem cell transplant. Thoracotomy was performed to remove the pulmonary lesion, but residual disease in the pleural cavity was noted. Treatment with amphotericin B was complicated by the development of severe renal dysfunction, necessitating alternative antifungal therapy. Treatment was initiated with the investigational triazole posaconazole. Despite concurrent treatment with corticosteroids for graft‐versus‐host disease (GVHD), the patient had a complete response and remains well 4 years later. © 2005 Wiley‐Liss, Inc.