bluuebunny/crossref_metadata_2025_split huggingface dataset:
A survey on exposure level, health status, and biomarkers in workers exposed to 1‐bromopropane
Authors: Ichihara Gaku , Li Weihua , Ding Xuncheng , Peng Simeng , Yu Xiaozhong , Shibata Eiji , Yamada Tetsuya , Wang Hailan , Itohara Seiichiro , Kanno Seiichiro , Sakai Kiyoshi , Ito Hidenori , Kanefusa Kato , Takeuchi Yasuhiro 
Published: December 2003

AbstractBackgroundThe aim of this study was to evaluate the health effects of exposure mainly to 1‐bromopropane, which is an alternative to ozone‐depleting solvents, and to establish biomarkers for assessing 1‐bromopropane exposure.MethodsTwenty‐four female and 13 male workers of a 1‐bromopropane‐factory were interviewed, and their urine and blood samples were collected. Measured parameters included 1‐bromopropane levels in the factory, as well as individual exposure levels, urinary 1‐bromopropane levels, enzymatic activity and M subunit's concentration of serum creatine kinase (CK).ResultsFrequent symptoms reported by workers exposed to 1‐bromopropane were nose, throat, and eyes irritation or malaise and/or headache. Urinary 1‐bromopropane levels correlated significantly with individual exposure levels, but enzymatic activity or CK–M subunit did not.ConclusionsThe symptoms suggested irritation of the mucous membrane and possible adverse effects on the central nervous system. There were no severe chronic symptoms suggestive of neurological damage in workers exposed to less than 170 ppm. Urinary 1‐bromopropane level may be a good indicator of exposure. Am. J. Ind. Med. 45:63–75, 2004. © 2003 Wiley‐Liss, Inc.
Occupational fatalities of Hispanic construction workers from 1992 to 2000
Authors: Dong Xiuwen , Platner James W. 
Published: December 2003

AbstractBackgroundHispanic construction employment has dramatically increased, yet published data on occupational risk is lacking.MethodsData from the Census of Fatal Occupational Injuries (CFOI) and current population survey (CPS) were examined from 1992 to 2000. Fatality rate, relative risk (RR), and risk index were calculated using CFOI fatality data and CPS data on hours worked, adjusted to full‐time‐equivalents (FTE). Data between 1996 and 2000 were combined to allow reliable comparisons of age and occupational groups. RR and 95% confidence intervals were calculated.ResultsIn 2000, Hispanics constituted less than 16% of the construction workforce yet suffered 23.5% of fatal injuries. RRs were: helpers, construction trades, 2.31 (95% CI: 1.41–3.80); roofers 1.77 (95% CI: 1.38–2.28); carpenters 1.39 (95% CI: 1.08–1.79); and construction laborers 1.31 (95% CI: 1.17–1.46).ConclusionsHispanic construction workers consistently faced higher RRs, for every year from 1992 to 2000 and for every age group. In 2000, Hispanic construction workers were nearly twice (1.84, 95% CI: 1.60–2.10) as likely to be killed by occupational injuries as their non‐Hispanic counterparts. Am. J. Ind. Med. 45:45–54, 2004. © 2003 Wiley‐Liss, Inc.
Exposure variability: Concepts and applications in occupational epidemiology
Authors: Loomis Dana , Kromhout Hans 
Published: December 2003

AbstractBackgroundStandard approaches to assessing exposures for epidemiologic studies tend to concentrate resources on obtaining detailed data for each study participant at the expense of characterizing within‐person variability.MethodsThis paper presents some basic, generalizeable concepts concerning exposure and its variability, describes methods that can be used to analyze, describe, and understand that variability, and reviews related implications for the design and interpretation of epidemiologic studies.Results and ConclusionsInsufficient attention to the balance of within‐ and between‐person variation in exposure can reduce the efficiency of measurement efforts and attenuate estimates of exposure‐disease association. Exposure variability should consequently be considered carefully in the planning, analysis, and interpretation of epidemiologic studies. Greater attention to these matters can lead to more meaningful characterization of exposure itself, and, most importantly, improve the chances that epidemiologic studies can identify and accurately characterize health hazards. Am. J. Ind. Med. 45:113–122, 2004. © 2003 Wiley‐Liss, Inc.
Zur Entwicklung der Dip‐Pen‐Nanolithographie
Authors: Ginger David S. , Zhang Hua , Mirkin Chad A. 
Published: December 2003

AbstractDie Möglichkeit zur gezielten Manipulation der chemischen Zusammensetzung und Struktur einer Oberfläche auf der Längenskala von 1 bis 100 nm ist von zentraler Bedeutung für einen breiten Bereich der nanotechnologischen Forschung, angefangen mit Studien zur elektronischen Leitfähigkeit, über die Katalyse hin zur biologischen Erkennung. Die Dip‐Pen‐Nanolithographie (DPN) ist eine neue Direktschreibmethode mit einem Kraftfeldmikroskop zur Erzeugung einer strukturierten chemischen Funktionalität auf einer Oberfläche im Sub‐100‐nm‐Bereich. In diesem Aufsatz stellen wir das Prinzip der DPN vor und betrachten die Entwicklungen der letzten Jahre. Die Themen erstrecken sich von der Entwicklung neuer DPN‐kompatibler Materialien über experimentelle und theoretische Untersuchungen der Prozesse, die den Spitze‐Substrat‐Transport der Tinte steuern, bis hin zur Implementierung von mikroelektromechanischen Systemen (MEMs) für DPN‐Parallelanwendungen.
A Planning Strategy for Diversity‐Oriented Synthesis
Authors: Burke Martin D. , Schreiber Stuart L. 
Published: December 2003

AbstractIn contrast to target‐oriented synthesis (TOS) and medicinal or combinatorial chemistry, which aim to access precise or dense regions of chemistry space, diversity‐oriented synthesis (DOS) populates chemical space broadly with small‐molecules having diverse structures. The goals of DOS include the development of pathways leading to the efficient (three‐ to five‐step) synthesis of collections of small molecules having skeletal and stereochemical diversity with defined coordinates in chemical space. Ideally, these pathways also yield compounds having the potential to attach appendages site‐ and stereoselectively to a variety of attachment sites during a post‐screening, maturation stage. The diverse skeletons and stereochemistries ensure that the appendages can be positioned in multiple orientations about the surface of the molecules. TOS as well as medicinal and combinatorial chemistries have been advanced by the development of retrosynthetic analysis. Although the distinct goals of DOS do not permit the application of retrosynthetic concepts and thinking, these foundations are being built on, by using parallel logic, to develop a complementary procedure known as forward‐synthetic analysis. This analysis facilitates synthetic planning, communication, and teaching in this evolving discipline.
Bioinspired Molecular Design of Light‐Harvesting Multiporphyrin Arrays
Authors: Choi Myung‐Seok , Yamazaki Tomoko , Yamazaki Iwao , Aida Takuzo 
Published: December 2003

AbstractRecent progress in fundamental studies on multiporphyrin arrays has provided structural parameters for the molecular design of artificial light‐harvesting antennae which mimic the wheel‐like antenna complexes of photosynthetic purple bacteria. Covalent and noncovalent approaches have been employed for the construction of artificial light‐harvesting multiporphyrin arrays. Such arrays are categorized into ring‐shaped, windmill‐shaped, star‐shaped, and dendritic architectures. In particular, dendritic multiporphyrin arrays have been proven to be promising candidates for both providing a large absorption cross‐section and enabling the vectorial transfer of energy over a long distance to a designated point. Such molecular and supramolecular systems are also expected to be potent components for molecular electronics and photonic devices.
Relationship of adipokinetic hormone I and II to migratory propensity in the grasshopper, Melanoplus sanguinipes
Authors: Min Kyung Jin , Taub‐Montemayor Tina E. , Linse Klaus D. , Kent Jack W. , Rankin Mary Ann 
Published: December 2003

AbstractThis report examines three aspects of adipokinetic hormone (AKH) involvement in migratory flight behavior in the grasshopper, Melanoplus sanguinipes. The titer of hemolymph AKH I during long‐duration tethered flight was examined using radioimmunoassay (RIA) after narrow bore RP‐HPLC. The hemolymph fraction containing AKH I was assayed using commercially available anti‐Tyr1‐AKH I serum. Titer determinations of hemolymph AKH were done at rest and after various periods of flight. The amount of AKH I released from the corpora cardiaca during flight was estimated. When resting levels of AKH I and II in corpora cardiaca (CC) of migrants and non‐migrants were examined with HPLC, no significant differences in AKH levels were detected between non‐migrants, animals that had flown for 1 h to identify them as migrants, and animals that had flown to exhaustion (i.e., voluntary cessation). CC levels of both AKH I and II were less in this species than in locusts. When the lipid mobilization in response to AKH I and II was compared in migrants (animals that had self‐identified as migrants in a 1‐h tethered flight test) and non‐migrants (animals that would not perform a 1‐h flight in a tethered flight test), the adipokinetic response to AKH I was greater in migrants than in non‐migrants, possibly indicating differences in level of sensitivity or number of receptors in the target tissues. AKH II had little effect on hemolymph lipid levels in either flight group, and may not play a significant role in lipid mobilization in this species. Arch. Insect Biochem. Physiol. 55:33–42, 2004. © 2003 Wiley‐Liss, Inc.
Pathways and destination of some male gland secretions in female Locusta migratoria migratorioides (R&F) after insemination
Authors: Lay Martin , Loher Werner , Hartmann Rüdiger 
Published: December 2003

AbstractThe white secretions (WS) from the tubules of the male accessory glands (AG) of Locusta migratoria are composed of peptides and proteins. The WS are transferred during mating to the female's spermatheca. They have been followed to their destinations with immunological and radioactive marker techniques. In the spermatheca, peptides are split off from WS‐protein complexes, permeate the spermathecal epithelium via glandular cells, enter the hemolymph and attach to other proteins in various target organs such as the dorsal fat body, the preterminal/terminal oocytes, and the follicular cells. In developing eggs, they concentrate at the posterior pole where sperm enters the egg, and in early embryogenesis they are found in the germ band. These results extend the functions of the spermatheca and the role of the male during the reproductive process. Arch. Insect Biochem. Physiol. 55:1–25, 2004. © 2003 Wiley‐Liss, Inc.
Stimulation of midgut stem cell proliferation by Manduca sexta α‐arylphorin
Authors: Blackburn Michael B. , Loeb Marcia J. , Clark Edward , Jaffe Howard 
Published: December 2003

AbstractExtracts of the green‐colored perivisceral fat body of newly ecdysed Manduca sexta pupae stimulate mitosis in midgut stem cells of Heliothis virescens cultured in vitro. Using a combination of cation‐ and anion‐exchange chromatography, we have isolated a protein from these fat body extracts that accounts for the observed stem cell proliferation. SDS‐PAGE analysis of the protein results in a single band of 77 kDa. Sequences of tryptic peptides from this protein are identical to internal sequences of the storage hexamer α‐arylphorin. The α‐arylphorin isolated by our procedure represents a small fraction of the total arylphorin present in the fat body extract. However, it alone seems responsible for the stimulation of mitotic activity in H. virescens midgut stem cells. Arch. Insect Biochem. Physiol. 55:26–32, 2004. Published 2003 Wiley‐Liss, Inc.
Immune stimulation in the silkworm, Bombyx mori L., by CpG oligodeoxynucleotides
Authors: Kim Iksoo , Kim Sang‐Hyun , Lee Young Shin , Yun Eun Kyung , Lee Heui‐Sam , Kim Jin‐Won , Ryu Kang‐Sun , Kang Pil‐Don , Lee In Hee 
Published: December 2003

AbstractSynthetic ODNs containing unmethylated CpG dinucleotides are known to stimulate immune responses in vertebrates, but so far the effect has not been studied in insects. In this report, we describe an induction of immune response following injection of oligodeoxynucleotides (ODNs) into the insect hemocoel. The fifth instar silkworm (Bombyx mori L.) larvae were injected with several synthetic ODNs containing variable number of unmethylated CpG motifs, heat‐denatured genomic DNA of B. mori itself, or intact genomic DNA to observe a new induction pattern in the insect immune mechanism. When the induction of immune response was examined based on the expression rates of genes for antibacterial peptides such as attacin and cecropin, we could confirm that it was triggered upon injection of ODNs. The expression was, however, neither dependent on numbers of CpG motifs nor methylation of CpGs in ODNs. Furthermore, it was confirmed that the presence of CpG in ODN was not involved in the induction pattern of insect immunity caused by ODNs, although it has been reported that vertebrates respond in a specific manner against invading ODNs containing CpG dinucleotides. In addition, insect immunity was not stimulated by injection of intact DNA from host. In contrast, the injection of denatured genomic DNA provoked the host immune reaction. Taken together, our data suggest that foreignness of ODNs or DNA might be a key factor in the induction of insect immunity. Arch. Insect Biochem. Physiol. 55:43–48, 2004. © 2003 Wiley‐Liss, Inc.
Determination of ampicillin and amoxycillin by flow injection chemiluminescence method based on their enhancing effects on the luminol–periodate reaction
Authors: Li Yinhuan , Tang Yuhai , Yao Hong , Fu Junmei 
Published: December 2003

AbstractIn this work, a new flow injection chemiluminescence method is described for the determination of ampicillin and amoxycillin. The method is based on the strong enhancing effects of these antibiotics on the luminol–periodate reaction. The present method allows the measurements of ampicillin in the range 0.02–1.0 mg/L range and amoxycillin in the range 0.1–10.0 mg/L range with the relative standard deviations within 0.8–2.0%. The sampling frequency was calculated about 90/h. The method was successfully applied to the determination of ampicillin and amoxycillin in pharmaceutical preparations. A brief discussion on the possible chemiluminescence reaction mechanism is presented. Copyright © 2003 John Wiley & Sons, Ltd.
A competitive marathon race decreases neutrophil functions in athletes
Authors: Chinda Daisuke , Nakaji Shigeyuki , Umeda Takashi , Shimoyama Tadashi , Kurakake Shigeyoshi , Okamura Noriyoshi , Kumae Takashi , Sugawara Kazuo 
Published: December 2003

AbstractA full marathon is the longest running race in official track events and is a form of acute exercise. However, no studies have examined the acute neutrophil function response to a competitive marathon race. Thirty‐six male athletes who had just completed the 42.195 km course of the 50th Beppu‐Oita Mainichi Marathon were enrolled in this study. Neutrophil oxidative burst activity, phagocytic activity and expression of CD11b and CD16 per cell were measured by flow cytometry immediately before and after the marathon. Total leukocyte/neutrophil counts increased significantly (p < 0.001), whereas total oxidative burst activity per neutrophil cell decreased significantly after the race (p < 0.001). Furthermore, total phagocytic activity per neutrophil cell also decreased after the race, although it was not significant (p = 0.08). Although CD11b expression per cell did not change, the expression of CD16 per cell significantly decreased (p < 0.001) after the race. In conclusion, a competitive marathon race decreased neutrophil functions (oxidative burst activity and phagocytic activity), which may be partly due to a decrease in CD16 expression. The increase in total neutrophil counts might reflect a compensatory response to counteract the decrease in neutrophil functions. Copyright © 2003 John Wiley & Sons, Ltd.
Ecabet sodium attenuates reactive oxygen species produced by neutrophils after priming with bacterial lipopolysaccharides
Authors: Munakata Wataru , Liu Qiang , Shimoyama Tadashi , Sawaya Manabu , Umeda Takashi , Sugawara Kazuo 
Published: December 2003

AbstractThe pathogenic roles of reactive oxygen species (ROS) have been implicated in ulcerative colitis (UC). The aim of this study was to examine the effects of ecabet sodium on ROS produced by human neutrophils, particularly after being primed by bacterial lipopolysaccharides (LPS). Neutrophils were isolated from six healthy volunteers. Each well of a 96‐well microplate received neutrophil suspension (1.0 × 105 cells) and the plates were incubated at 37°C for 30 min with or without E. coli LPS (f.c. 0.001 ng/µL). Ecabet sodium (f.c. 0–5.0 mg/mL) was added before starting or after finishing the incubation. Neutrophils were stimulated by opsonized zymosan (OZ; 1.0 mg/mL) or calcium ionophore (A21837; 0.3 µmol/L) and luminol‐dependent chemiluminescence response was measured using a Lumi Box H‐1000. Ecabet sodium attenuated ROS production at a concentration of 5.0 mg/mL (p < 0.05) in LPS‐primed neutrophils. However, attenuating effects were not significantly different when ecabet sodium was added before or after the incubation with E. coli LPS. Ecabet sodium may have some attenuating effects on ROS produced by human neutrophils even after neutrophils are primed by bacterial LPS. These results may explain, in part, the therapeutic effects of ecabet sodium for UC. Copyright © 2003 John Wiley & Sons, Ltd.
Synthesis, stability, and protonation studies of a self‐complementary dodecamer containing the modified nucleoside 2′‐deoxyzebularine
Authors: Vives M. , Eritja R. , Tauler R. , Marquez V. E. , Gargallo R. 
Published: December 2003

AbstractThe nucleoside 2′‐deoxyzebularine (K) was incorporated into the self‐complementary dodecamer 5′‐CGTACGKGTACG‐3′ by solid‐phase 2‐cyanoethylphosphoramidite chemistry using dimethoxytrityl (DMT) as the 5′‐hydroxyl protecting group. Standard synthesis cycles using trichloroacetic acid and short ammonia treatment (50°C for 30 min) were found to be the optimal conditions to obtain the desired dodecamer with minimum acid and basic degradation of the acid‐ and base‐sensitive 2‐pyrimidinone residue. The protonation equilibria of the K nucleoside and of the dodecamer at 37°C were studied by means of spectroscopically monitored titrations. For the K nucleoside, a pKa value of 3.13 ± 0.09 was obtained. For the dodecamer, four acid‐base species were found in the pH range 2–12, with pKa values of 9.60 ± 0.07, 4.46 ± 0.16, and 2.87 ± 0.19. Melting experiments were carried out to confirm the proposed acid‐base concentration profiles. Finally, kinetic experiments were also carried out at several pH values to evaluate the stability of the K nucleoside and of the dodecamer. An increased stability was shown by the K nucleoside when incorporated into the dodecamer. Multivariate methods based on both hard‐ and soft‐modeling were applied for the analysis of spectroscopic data, allowing the estimation of concentration profiles and pure spectra. © 2003 Wiley Periodicals, Inc. Biopolymers 70: 27–43, 2004
Understanding the transition states of phosphodiester bond cleavage: Insights from heavy atom isotope effects
Authors: Cassano Adam G. , Anderson Vernon E. , Harris Michael E. 
Published: December 2003

AbstractThe nucleotides of DNA and RNA are joined by phosphodiester linkages whose synthesis and hydrolysis are catalyzed by numerous essential enzymes. Two prominent mechanisms have been proposed for RNA and protein enzyme catalyzed cleavage of phosphodiester bonds in RNA: (a) intramolecular nucleophilic attack by the 2′‐hydroxyl group adjacent to the reactive phosphate; and (b) intermolecular nucleophilic attack by hydroxide, or other oxyanion. The general features of these two mechanisms have been established by physical organic chemical analyses; however, a more detailed understanding of the transition states of these reactions is emerging from recent kinetic isotope effect (KIE) studies. The recent data show interesting differences between the chemical mechanisms and transition state structures of the inter‐ and intramolecular reactions, as well as provide information on the impact of metal ion, acid, and base catalysis on these mechanisms. Importantly, recent nonenzymatic model studies show that interactions with divalent metal ions, an important feature of many phosphodiesterase active sites, can influence both the mechanism and transition state structure of nonenzymatic phosphodiester cleavage. Such detailed investigations are important because they mimic catalytic strategies employed by both RNA and protein phosphodiesterases, and so set the stage for explorations of enzyme‐catalyzed transition states. Application of KIE analyses for this class of enzymes is just beginning, and several important technical challenges remain to be overcome. Nonetheless, such studies hold great promise since they will provide novel insights into the role of metal ions and other active site interactions. © 2003 Wiley Periodicals, Inc. Biopolymers 73: 110–129, 2004
New approaches to targeting RNA with oligonucleotides: Inhibition of group I intron self‐splicing
Authors: Disney Matthew D. , Childs Jessica L. , Turner Douglas H. 
Published: December 2003

AbstractRNA is one class of relatively unexplored drug targets. Since RNAs play a myriad of essential roles, it is likely that new drugs can be developed that target RNA. There are several factors that make targeting RNA particularly attractive. First, the amount of information about the roles of RNA in essential biological processes is currently being expanded. Second, sequence information about targetable RNA is pouring out of genome sequencing efforts at unprecedented levels. Third, designing and screening potential oligonucleotide therapeutics to target RNA is relatively simple. The use of oligonucleotides in cell culture, however, presents several challenges such as oligonucleotide uptake and stability, and selective targeting of genes of interest. Here, we review investigations aimed at targeting RNA with oligonucleotides that can circumvent several of these potential problems. The hallmark of the strategies discussed is the use of short oligonucleotides, which may have the advantage of higher cellular uptake and improved binding selectivity compared to longer oligonucleotides. These strategies have been applied to Group I introns from the mammalian pathogens Pneumocystis carinii and Candida albicans. Both are examples of fungal infections that are increasing in number and prevalence. © 2003 Wiley Periodicals, Inc. Biopolymers 73: 151–161, 2004