bluuebunny/crossref_metadata_2025 huggingface dataset:
Evaluation of a portable blood lead analyzer with occupationally exposed populations†*
Authors: Taylor Lauralynn , Jones Robert L. , Kwan Lorna , Deddens James A. , Ashley Kevin , Sanderson Wayne T.
Published: August 2002

Background

This project evaluated a portable electroanalytical instrument that is used to rapidly analyze blood lead levels in individuals, using a fresh whole blood sample (venous).

Methods

Samples were obtained from 208 lead‐exposed employees who donated two 2 ml venous blood samples into “lead‐free” evacuated tubes. One blood sample was analyzed onsite using the portable field instrument while the second sample was analyzed using graphite furnace atomic absorption spectrometry (GFAAS).

Results

According to GFAAS results, employee venous blood lead levels ranged from 1 μg/dl to 42 μg/dl. The mean difference between the results from the field instrument and GFAAS was less than 1 μg/dl. Analysis indicates that the results from the field instrument yielded a slight positive bias overall (P value = 0.0213), with less bias for blood lead levels above 10 μg/dl (P value = 0.0738).

Conclusions

Within the blood range evaluated (1–42 μg/dl), the instrument performed adequately according to Clinical Laboratory Improvements Amendments (CLIA) proficiency requirements. The ability of the instrument to perform rapid analysis makes it potentially valuable to occupational health professionals for medical monitoring or on‐site investigations. Am. J. Ind. Med. 40:354–362. 2001. Published 2001 Wiley‐Liss, Inc.
An association study of DRD5 with smoking initiation and progression to nicotine dependence
Authors: Sullivan Patrick F. , Neale Michael C. , Silverman Michael A. , Harris‐Kerr Carol , Myakishev Maxim V. , Wormley Brandon , Webb B. Todd , Ma Yunlong , Kendler Kenneth S. , Straub Richard E.
Published: August 2002

A large body of genetic epidemiological data strongly implicate genetic factors in the etiology of smoking behavior. Polymorphisms of genes in the dopaminergic system are plausible functional candidate genes and a linkage and an association study suggested that the type 5 dopamine receptor gene (DRD5) may be etiologically involved. We investigated the association of four DRD5 polymorphisms with smoking initiation and progression to nicotine dependence in a population‐based sample of over 900 subjects. For smoking initiation, there was no significant association with the four DRD5 markers we studied; however, maximum likelihood analyses suggested the presence of a haplotype protective against smoking initiation. For progression to nicotine dependence, there were no strongly significant associations with the four DRD5 markers or for the estimated haplotypes. These data are not consistent with a strong etiological role for DRD5 in the etiology of these complex smoking behaviors. © 2001 Wiley‐Liss, Inc.
A genomewide linkage study of age at onset in schizophrenia*
Authors: Cardno Alastair G. , Holmans Peter A. , Rees Mark I. , Jones Lisa A. , McCarthy Geraldine M. , Hamshere Marian L. , Williams Nigel M. , Norton Nadine , Williams Hywel J. , Fenton Iain , Murphy Kieran C. , Sanders Robert D. , Gray Marion Y. , O'Donovan Michael C. , McGuffin Peter , Owen Michael J.
Published: August 2002

There is strong evidence for a genetic contribution to age at onset of schizophrenia, which probably involves both susceptibility loci for schizophrenia and modifying loci acting independent of disease risk. We sought evidence of linkage to loci that influence age at onset of schizophrenia in a sample of 94 affected sibling pairs with DSM‐IV schizophrenia or schizoaffective disorder, and age at first psychiatric contact of 45 years or less. Individuals were genotyped for 229 microsatellite markers spaced at approximately 20 cM intervals throughout the genome. Loci contributing to age at onset were sought by a quantitative maximum‐likelihood multipoint linkage analysis using MAPMAKER/SIBS. A nonparametric multipoint analysis was also performed. The genomewide significance of linkage results was assessed by simulation studies. There were six maximum‐likelihood LOD score peaks of 1.5 or greater, the highest being on chromosome 17q (LOD = 2.54; genomewideP = 0.27). This fulfils Lander and Kruglyak's [1995: Nat Genet 11:241–247] criteria for suggestive linkage in that it would be expected to occur once or less (0.3 times) per genome scan. However, this finding should be treated with caution because the LOD score appeared to be almost solely accounted for by the pattern of ibd sharing at one marker (D17S787), with virtually no evidence of linkage over flanking markers. None of the linkage results achieved genomewide statistical significance, but the LOD score peak on chromosome 13q (LOD = 1.68) coincided with the region showing maximum evidence for linkage in the study by Blouin et al. [1998: Nat Genet 20:70–73] of categorical schizophrenia. © 2001 Wiley‐Liss, Inc.
Sex identification assay useful in great apes is not diagnostic in a range of other primate species
Authors: Ensminger Amanda L. , Hoffman Susan M.G.
Published: August 2002

The ability to identify the sex of individuals from noninvasive samples can be a powerful tool for field studies. Amelogenin, a nuclear gene proximate to the pseudoautosomal region of mammalian sex chromosomes, has a 6 base‐pair (bp) size difference between human X and Y chromosomes that can be PCR‐amplified and sized to distinguish male from female DNA. We examined whether this test can be used to identify sex from different DNA sources across a number of nonhuman primate taxa. Using human amelogenin primers, we were able to amplify diagnostic products from the four great ape species tested, but products from five other primate species were not sexually dimorphic. Am. J. Primatol. 56:129–134, 2002. © 2002 Wiley‐Liss, Inc.
Geometric morphometric study of the regional variation of modern human craniofacial form
Authors: Hennessy Robin J. , Stringer Chris B.
Published: August 2002

The regional variability of the modern human craniofacial form is of importance to debates about human origins. The study of craniofacial form has generally been carried out either by interlandmark distance measurement and analysis or by observation and character scoring. In this study of four modern human groups (Eskimo/Inuit, African, Australian, and Romano‐British), nine craniofacial landmark coordinates were recorded by extraction from laser scans. The coordinates were studied by geometric morphometrics, and a regression analysis was used to investigate the dominant variability in shape within and between groups. Statistical tests of shape difference between groups were carried out. By these methods, the statistical patterns of shape variability and their geometric interpretations were studied on a common basis. The results were found to be in agreement with the classic studies of Howells ([1989:189] Pap Peabody Mus 79), and show the potential of this approach for future research. Am J Phys Anthropol 117:37–48, 2002. © 2002 Wiley‐Liss, Inc.
Male orangutan subadulthood: A new twist on the relationship between chronic stress and developmental arrest
Authors: Maggioncalda Anne N. , Czekala Nancy M. , Sapolsky Robert M.
Published: August 2002

Both in the wild and in captivity, a marked and enduring arrest of secondary sexual developmental occurs in some male orangutans (Pongo pygmaeus) (Kingsley [1982] The Orang‐Utan: Its Biology and Conservation, The Hague: Junk; Utami [2000]). Researchers have hypothesized that chronic stress, perhaps related to aggression from mature males, causes endocrine changes altering growth and maturation rates in these males (Maple [1980] Orangutan Behavior, New York: Van Nostrand Reinhold; Graham [1988] Orangutan Biology, Oxford: Oxford University Press). In this study, urine samples were collected over a 3‐year period from 23 captive male orangutans to test the hypothesis that developmentally arrested male orangutans have an endocrine profile consistent with chronic stress. Three study males were juveniles, seven were arrested adolescents, six were developing adolescents, and seven were mature adults. Morning samples were analyzed by radioimmunoassay for levels of the stress hormones cortisol and prolactin, and group hormone profiles were compared by analysis of variance. Results indicate that developing adolescent male orangutans have a significantly higher stress hormone profile than juvenile, developmentally arrested adolescent, or adult males. These results imply that the arrest of secondary sexual development in some male orangutans is not stress‐induced, but instead perhaps an adaptation for stress avoidance during the adolescent or “subadult” period. These data, together with previously reported data on levels of gonadotropins, testicular steroids, and growth‐related hormones, define endocrine profiles associated with alternative reproductive strategies for males with and males without secondary sexual features (Maggioncalda et al. [1999], [2000]. Am J Phys Anthropol 118:25–32, 2002. © 2002 Wiley‐Liss, Inc.
Analysis of tufted capuchin (Cebus apella) courtship and sexual behavior repertoire: Changes throughout the female cycle and female interindividual differences
Authors: Carosi Monica , Visalberghi Elisabetta
Published: August 2002

Sexual solicitations and initiative (proceptivity, sensu Beach [1976] Horm Behav 7:105–138) are important components of the sexuality of females of many primate species. In the tufted capuchin (Cebus apella), female proceptivity characterizes the species' mating system. In study 1, we defined and discussed 20 behavioral patterns based on the observation of 6 females and 5 males living in two social groups. In study 2, each behavior, including mounting activity, was quantitatively assessed during the periovulatory and nonperiovulatory cycle phases of 4 females, detected on the basis of urinary progestin levels (N = 20 ovulatory cycles, 5 for each female); moreover, we monitored changes in females' social interactions (agonism, grooming activity, and play). Nine of the behaviors typically used by the female during courtship and in sexual interactions showed a dramatic increase during the periovulatory phase. Though males mounted females at an apparently higher rate during the periovulatory than the nonperiovulatory phase, the difference was not significant. However, when adult male mounting is separated into those which occur within play and nonplay contexts, there is a significant periovulatory phase effect for mounts not associated with play. Females groomed adult males at the same rate throughout the cycle. Agonism and play did not show any phase effect; however, females' avoidance of adult males significantly increased during the periovulatory phase. Finally, each female made a statistically different use of the behavioral repertoire by performing some behaviors more than others. This variability among females during courtship calls for further research into whether it affects mating success. Am J Phys Anthropol 118:11–24, 2002. © 2002 Wiley‐Liss, Inc.
Cell death in experimental intracerebral hemorrhage: The “black hole” model of hemorrhagic damage
Authors: Felberg Robert A. , Grotta James C. , Shirzadi Ali L. , Strong Roger , Narayana Ponnada , Hill‐Felberg Sandra J. , Aronowski Jaroslaw
Published: August 2002

Intracerebral hemorrhage (ICH) has a poor prognosis that may be the consequence of the hematoma's effect on adjacent and remote brain regions. Little is known about the mechanism, location, and severity of such effects. In this study, rats subjected to intracerebral blood injection were examined at 100 days. Stereology (neuronal count and density) and volume measures in the perihematoma rim, the adjacent and overlying brain, and the substantia nigra pars reticulata (SNr) were compared with contralateral brain regions at 100 days and the perihemorrhage region at 24 hours and 7 days. In addition, cytochrome c release was investigated at 24 hours, 3 days, and 7 days. At 100 days, post‐ICH rats showed no difference in neuronal density in the perihemorrhagic scar region or regions of the striatum immediately surrounding and distal to the perihemorrhage scar. The cell density index in the ipsilateral field was 16.2 ± 3.8 versus the contralateral control field of 15.6 ± 3.2 (not significant). Volume measurements of the ipsilateral striatum revealed a 20% decrease that was compensated by an increase in ipsilateral ventricular size. The area of the initial ICH as measured by magnetic resonance imaging correlated with the degree of atrophy. In the region immediately surrounding the hematoma, cytochrome c immunoreactivity increased at 24 hours and 3 days, and returned toward baseline by day 7. At 24 hours, stereology in the peri‐ICH region showed decreased density in the region where cytochrome c immunoreactivity was the highest. Neuronal density of the ipsilateral SNr was significantly less than the contralateral side (9.6 ± 1.9 vs 11.6 ± 2.3). Histologic damage from ICH occurred mainly in the immediate perihemorrhage region. Except for SNr, we found no evidence of neuronal loss in distal regions. We have termed this continued destruction of neurons, which occurs over at least 3 days as the neurons come into proximity to the hematoma, the “black hole” model of hemorrhagic damage.
Plasticization of cellulose diacetate by graft copolymerization of ε‐caprolactone and lactic acid
Authors: Teramoto Yoshikuni , Yoshioka Mariko , Shiraishi Nobuo , Nishio Yoshiyuki
Published: August 2002

Graft copolymerization of ε‐caprolactone (CL) and lactic acid (LA) onto cellulose diacetate (CDA) at the residual hydroxyl positions was conducted to obtain thermoplastic CDA. The effects of the reaction temperature and time and the CL/LA molar ratio in the feed on the progress of the graft copolymerization were investigated. The molecular weight of CDA was increased by this graft copolymerization. The oxycaproyl and lactyl molar substitutions (MSCLand MSLA, respectively) in grafted CDA (g‐CDA) were determined through1H‐NMR spectral analysis. These MS values were controllable by changing the reaction conditions adequately. The flow temperature and melt viscosity ofg‐CDA decreased with an increase in the total substitution of MSCLand MSLA, and transparent polymer sheets could be obtained from the resultingg‐CDA by hot pressing at around 200°C without adding any plasticizer. The mechanical properties of the moldedg‐CDA samples varied widely, depending on the different combinations of the MSCLand MSLAvalues; theg‐CDA sheets became elastic when the MSCLwas larger than the MSLA, and their tensile strengths were enhanced as the MSLAwas increased. It was thus found that CDA was successfully plasticized by this graft copolymerization. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 84: 2621–2628, 2002
Mechanical properties and deformation mechanisms in high thermal resistant poly(acrylonitrile‐butadiene‐styrene) under static tension and Izod impact
Authors: Jar P.‐Y. B. , Creagh D. C. , Konishi K. , Shinmura T.
Published: August 2002

Deformation mechanisms in a high thermal resistant poly(acrylonitrile‐butadiene‐styrene) (ABS) were investigated using transmission electron microscopy (TEM) and small‐angle X‐ray scattering (SAXS). The work followed our previous study, in which TEM was used for the craze observation and SAXS for the shear yielding, to evaluate the relationship between the mechanical properties and the deformation mechanisms of the ABS under static tension and Izod impact. The current results support our previous conclusion that the combination of TEM and SAXS enables us to identify the deformation mechanisms in the ABS, and provide new evidence for the coexistence of crazing and shear yielding. The SAXS patterns suggest that shear yielding occurred in the ABS, even under the impact loading. We concluded from the study that the occurrence of shear yielding had a major effect on the toughness enhancement of the ABS. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 85: 17–24, 2002
pH‐sensitive shrinking of a dextran sulfate/chitosan complex gel and its promotion effect on the release of polymeric substances
Authors: Sakiyama Takaharu , Takata Hajime , Toga Takehiro , Nakanishi Kazuhiro
Published: August 2002

A pH‐sensitive gel was prepared by polyelectrolyte complex formation between dextran sulfate and chitosan. When the complex gel contained more amino groups than sulfate groups, it shrank pronouncedly at around pH 7 in NaCl solutions of various concentrations, probably because of the deionization of protonated amino groups remaining free from electrostatic interaction with the sulfate groups. Using the complex gel loaded with dextran by absorption, releasing behaviors were studied under various conditions. It was shown that shrinking of the complex gel had a promotion effect on the release of dextran. In 170 mM NaCl solution, the complex gel released dextran more rapidly at pH 8 than at pH 2, because the degree of shrinking was greater at pH 8. Thus, the promotion effect of the complex gel on the release of dextran was pH dependent, though the release rates at the two pHs became closer as the average molecular weight of dextran loaded was lowered. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 81: 667–674, 2001
Release and diffusion of sulfamethoxazole through acrylamide‐based hydrogel
Authors: Bajpai A. K. , Rajpoot M.
Published: August 2002

Two polymeric hydrogels (xerogels) containing poly(vinyl pyrrolidone) (PVP)‐crosslinked polyacrylamide and poly(vinyl alcohol) (PVA)‐crosslinked polyacrylamide were loaded with the sulfamethoxazole drug and their swelling and drug‐release dynamics were investigated at a fixed pH and at room temperature (27°C). The effects of various factors such as the composition of the xerogel, crosslinking density, and drug loading were studied on the swelling and drug‐release pattern of the xerogels. The kinetic parameters such as the diffusion exponent (n), diffusion constant (k), and diffusion coefficient (D) were also evaluated and analyzed. The percent drug released by these xerogels was also compared to that by the crosslinked gelatin gels. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 81: 1238–1247, 2001
Plasma‐induced graft polymerization of acrylic acid onto poly(ethylene terephthalate) films
Authors: Gupta Bhuvanesh , Hilborn Jons G. , Bisson Isabelle , Frey Peter
Published: August 2002

The graft polymerization of acrylic acid was carried out onto poly(ethylene terephthalate) films that had been pretreated with argon plasma and subsequently exposed to oxygen to create peroxides. The influence of synthesis conditions, such as plasma treatment time, plasma power, monomer concentration, temperature, and the presence of Mohr's salt, on the degree of grafting was investigated. The observed initial increase in grafting with monomer concentration accelerated at about 20% monomer. The grafting reached a maximum at 40% monomer and subsequently decreased with further increases in monomer concentration. The reaction temperature had a pronounced effect on the degree of grafting. The initial rate of grafting increased with increasing temperature, but the degree of grafting showed a maximum at 50°C. The activation energy of the grafting obtained from an Arrhenius plot was 29.1 kJ/mol. The addition of Mohr's salt to the reaction medium not only led to a homopolymer‐free grafting reaction but also diminished the degree of grafting. The degree of grafting increased with increasing plasma power and plasma treatment time. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 81: 2993–3001, 2001
Electrically conductive, melt‐processed polyaniline/EVA blends
Authors: Barra Guilherme M. O. , Leyva Maria Elena , Soares Bluma G. , Mattoso L. H. , Sens Marcio
Published: August 2002

Mechanical blends of ethylene–vinyl acetate copolymer and polyaniline doped with dodecyl benzene sulfonic acid (PAni–DBSA) were prepared in a two‐roll mill at 50°C and in a Haake internal mixer at 150°C. The effects of the blend composition and processing conditions on the electrical conductivity and mechanical properties were investigated. These blends exhibited high levels of electrical conductivity at a small amount of PAni complex. Blends prepared in a two‐roll mill displayed conductivity values as high as 1 S/cm and a higher protonation degree than the pure PAni–DBSA, as indicated by X‐ray photoelectron spectroscopy. Two different insulator–conductor transition points were observed in these blends. The mechanical performance decreased as the amount of PAni–DBSA increased, indicating blend incompatibility and a plasticizing effect of the DBSA. The morphology of the blends were studied by scanning electron microscopy. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 82: 114–123, 2001
In vitrodegradation behavior of carbon fiber‐reinforced PLA composites and influence of interfacial adhesion strength
Authors: Wan Y. Z. , Wang Y. L. , Xu X. H. , Li Q. Y.
Published: August 2002

In the present study, carbon fiber‐reinforced polylactide (C/PLA) composites with different interfacial conditions were prepared to determine the influence of interfacial adhesion strength (IAS) onin vitrodegradation behavior of the C/PLA composites. Pure PLA and untreated and treated C/PLA composite samples were immersed in phosphate buffered saline (PBS; pH 7.4, 37 ± 0.5°C) for predetermined time periods. These samples were removed at each degradation time, measured to analyze molecular weight loss, weighed to assess water uptake and mass loss, and mechanically tested to obtain bending strength, modulus, and IAS. The matrixes in the C/PLA composites showed higher water uptake and lower mass loss in comparison with the pure PLA. Further, the PLA matrix in the treated composite absorbed less water and lost less mass and molecular weight than its counterpart in the untreated composite. Mechanical tests confirmed that the treated C/PLA composite exhibited a slower rate of decrease in bending strength, modulus, and IAS than the untreated one. The differences in degradation behavior between two composites can only be attributed to the difference in interfacial conditions because all other parameters were kept constant. The loss of bending strength and modulus was mainly caused by the interface degradation of the C/PLA composites. It can be concluded from ourin vitroobservations that the IAS had an obvious influence on the degradation characteristics of the C/PLA composites. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 82: 150–158, 2001
Clay nanolayer reinforcement of cis‐1,4‐polyisoprene and epoxidized natural rubber
Authors: Vu Yen T. , Mark James E. , Pham Ly H. , Engelhardt Martin
Published: August 2002

Conditions were established for dispersing clay nanolayers into both cis‐1,4‐polyisoprene (synthetic) natural rubber (NR) and epoxidized natural rubbers (ENR) having 25 or 50 mol % epoxide. The clay was a sodium montmorillonite and was used as a pristine layered silicate or as organically modified layered silicates to make the galleries more hydrophobic and thus more compatible with the elastomers. The chemical modifications were carried out using an ion‐exchange reaction with alkyl ammonium cations. Incorporation of the clays into the elastomers was achieved by mixing the components themselves in a standard internal blender or by mixing dispersions of them in toluene or methyl ethyl ketone. X‐ray diffraction results indicated intercalation of NR and ENR into the silicate interlayers, followed by exfoliation of the silicate layers into the elastomer matrices. Of primary interest was the effect of the intercalated and exfoliated clays on the mechanical properties of the elastomers. The reinforcing effects obtained were found to depend strongly on the extent of the dispersion of the silicate layers into the rubber matrices. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 82: 1391–1403, 2001
Large volume, high‐performance applications of fibers in civil engineering
Authors: Li Victor C.
Published: August 2002

This article presents an overview of fiber applications in cementitious composites. The socio‐economic considerations surrounding materials development in civil engineering in general, and fiber reinforced cementitious materials in particular, are described. Current FRC appliations are summarized, and the where, how, and why fibers are used in these applications, are documented. An attempt is made to extract common denominators among the widely varied applications. The R&D and industrial trends of applying fibers in enhancing structural performance are depicted. An actual case study involving a tunnel lining constructed in Japan is given to illustrate how a newly proposed structural design guideline takes into account the load carrying contribution of fibers. Composite properties related to structural performance are described for a number of FRCs targeted for use in load carrying structural members. Structural applications of FRCs are currently under rapid development. In coming years, it is envisioned that the ultra‐high performance FRC, with ductility matching that of metals, will be commercially exploited in various applications. Highlights of such a material are presented in this article. Finally, conclusions on market trends are drawn, and favorable fiber characteristics for structural applications are provided. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 83: 660–686, 2002
Synthesis and characterization of biodegradable poly(ester‐urethanes) based on bacterial poly(R‐3‐hydroxybutyrate)
Authors: Saad Gamal R. , Lee Y. J. , Seliger H.
Published: August 2002

A series of poly(R‐3‐hydroxybutyrate)/poly(ε‐caprolactone)/1,6‐hexamethylene diisocyanate‐segmented poly(ester‐urethanes), having different compositions and different block lengths, were synthesized by one‐step solution polymerization. The molecular weight of poly(R‐3‐hydroxybutyrate)‐diol, PHB‐diol, hard segments was in the range of 2100–4400 and poly(ε‐caprolactone)‐diol, PCL‐diol, soft segments in the range of 1080–5800. The materials obtained were investigated by using differential scanning calorimetry, wide angle X‐ray diffraction and mechanical measurements. All poly(ester‐urethanes) investigated were semicrystalline withTmvarying within 126–148°C. DSC results showed thatTgare shifted to higher temperature with increasing content of PHB hard segments and decreasing molecular weight of PCL soft segments. This indicates partial compatibility of the two phases. In poly(ester‐urethanes) made from PCL soft segments of molecular weight(Mn≥ 2200), a PCL crystalline phase, in addition to the PHB crystalline phase, was observed. As for the mechanical tensile properties of poly(ester‐urethane) cast films, it was found that the ultimate strength and the elongation at the breakpoint decrease with increasing PHB hard segment content. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 83: 703–718, 2002
In situ heparin‐induced peroxisomal reticulum and biogenesis of peroxisomes in pulmonary intravascular macrophages (PIMs) of caprine lung: an ultrastructural and cytochemical study
Authors: Atwal Onkar S. , Williams Carol S. , Minhas Kanwal J. , Nijjar Mohinder S.
Published: August 2002

Pulmonary intravascular macrophages (PIMs) contain a unique electron‐dense globular surface‐coat which is sensitive to heparin treatment, halothane anesthesia, and the digestive effect of lipolytic lipase (LPL), suggesting that the coat is predominantly composed of lipoproteins. In the present study, evidence is presented that heparin, when administered intravenously in goats, potentiated both the translocation of the surface‐coat into the vacuolar system and the expansion of the Golgi apparatus. Sequentially, these changes were followed by proliferation of peroxisomes in combination with peroxisomal reticulum (PR), a transient precursor of this organelle. The peroxisomes, as well as PR, reacted positively for catalase after aldehyde fixation and 3,3′‐diaminobenzidine (DAB) staining. In addition to their role as phagocytes, the ultrastructural and cytochemical detection of peroxisomes suggests a functional capacity of the PIMs, which may be adaptable to the circulating level of free fatty acids (FAAs). Anat Rec 266:69–80, 2002. © 2002 Wiley‐Liss, Inc.
Topography of corpuscular mechanoreceptors in the shoulder joint region of monodelphis domestica
Authors: Maass Stefan , Baumann Klaus I. , Halata Zdenek
Published: August 2002

The topography and structure of corpuscular mechanoreceptors in the shoulder joint capsule and periarticular connective tissue of a small laboratory marsupial (monodelphis domestica) were studied using light and electron microscopy. This animal is known to use its upper extremities for a wide range of activities like climbing and manipulating food. Thus, the shoulder joint of this animal species has a similar wide range of movement as the human shoulder joint, but is small enough for serial sectioning in its entirety. Silver stained serial paraffin sections were examined under the light microscope and the distribution of the different types of mechanoreceptors was reconstructed using three‐dimensional image processing. In addition, selected mechanoreceptors were studied electron microscopically. Approximately 100 small lamellated corpuscles were found in the dense connective tissue of the joint capsule close to the insertion on the scapula and in the thickening of the joint capsule close to the glenoid labrum. Ruffini corpuscles were found in much smaller numbers in the moderately dense connective tissue of the axillary region. Only very few Vater‐Pacinian corpuscles were seen in the soft periarticular connective tissue. The large number and localization of mechanoreceptor corpuscles in the shoulder joint capsule especially close to the glenoid labrum suggests, that these specialized nerve endings are likely to play an important role in control of joint movement. They can induce protective reflexes during extreme movements in the shoulder joint preventing shoulder luxation by increasing the tone of muscles pressing the humerus head into the glenoid cavity. Anat Rec 263:35–40, 2001. © 2001 Wiley‐Liss, Inc.
Absorption and tissue distribution of cholesterol in Manduca sexta
Authors: Jouni Zeina E. , Zamora Jorge , Wells Michael A.
Published: August 2002

In Manduca sexta larvae, radioactive free cholesterol is absorbed directly from the midgut into mucosal cells where it is stored both in the free form (87% in males and 93% in females) and esterified form (13% in males and 7% in females). Subsequently, cholesterol is transported to fat body via lipophorin in the hemolymph exclusively in the free form. In fat body, the distribution of cholesterol between the free and esterified form varied significantly between genders and developmental stages. Except for the larval stage, males and females were able to store cholesterol in both free and esterified forms in the fat body and in the adult stage cholesterol ester accounted for more than 75% of the stored cholesterol. Placement of radioactive cholesterol at different locations in the gut—foregut, midgut, and hindgut—demonstrated that the midgut is the site where cholesterol is absorbed and released into the hemolymph. Cholesterol‐labeled lipophorin injected into larval hemolymph was cleared from the hemolymph with a half‐life of 10.2 h. After 17 h, most of the cleared radioactivity was recovered in the fat body (38%). Arch. Insect Biochem. Physiol. 49:167–175, 2002. © 2002 Wiley‐Liss, Inc.
Proteins synthesized and secreted by larvae of the ectoparasitic wasp, Eulophus pennicornis
Authors: Richards Elaine H. , Edwards John P.
Published: August 2002

A microscopic examination of Eulophus pennicornis larvae on their host Lacanobia oleracea, revealed that peristaltic waves travelled from the anterior to posterior end of the feeding wasp larvae, and vice versa. In addition, when wasp larvae were immersed in PBS in vitro, they released a variety of proteins, with molecular weights ranging from (at least) 14 to 200 kDa. Amongst these was a protein with an estimated molecular weight similar to that of the 27 kDa parasitism‐specific protein (PSP) detected in plasma from parasitized L. oleracea [Richards and Edwards, Insect Biochem Mol Biol 29:557–569 (1999)]. Similar results were obtained when the wasp larvae were incubated on balls of cotton wool soaked in tissue culture medium or sucrose, i.e., conditions that resemble their natural feeding behaviour. These results (and others) indicate that the wasp larvae release proteins, putatively through their mouth. Protein synthesis studies using 35S‐methionine indicated that the wasp larvae synthesize and secrete a variety of proteins in vitro, including one with a molecular weight corresponding to that of the L. oleracea 27 kDa PSP. As expected, only a portion of the total proteins synthesized by the parasitoid larvae were subsequently secreted. In addition, the autoradiogram of secreted proteins contained significantly fewer bands than silver‐stained SDS gels of proteins released into PBS or onto cotton wool. Thus, some of the additional bands detected on the latter gels are thought to represent proteins that were not of wasp origin. Instead, these proteins released by the wasp larvae are speculated to be derived from their gut and, as such, probably represent proteins derived from host haemolymph and ingested during feeding. This possibility was supported by an electrophoretic analysis of homogenate supernatants prepared from wasp larvae with or without their gut contents. These studies indicated that the gut contents of the larval parasitoid contributes several distinct bands to the total protein profile. The ability of E. pennicornis larvae to synthesize, secrete, and release proteins is discussed with reference to those produced by endoparasitoid larvae. Arch. Insect Biochem. Physiol. 46:140–151, 2001. Published 2001 Wiley‐Liss, Inc.
Lepidopteran peritrophic membranes and effects of dietary wheat germ agglutinin on their formation and structure
Authors: Hopkins Theodore L. , Harper Marc S.
Published: August 2002

Peritrophic membrane (PM) structure and the effects of dietary wheat germ agglutinin (WGA) on PM formation were studied in larvae of the European corn borer (ECB), Ostrinia nubilalis, and the tobacco hornworm (THW), Manduca sexta. Growth of ECB was strongly inhibited by low amounts of WGA in the diet (0.05%), whereas THW was not affected by amounts of up to 2%. In ECB larvae, chitin microfibrils were secreted to form an orthogonal network within the apical region of the anterior midgut microvilli. The network then moved to the tips of the microvilli where proteinacious matrix was added prior to delamination of a single PM into the lumen to enclose the food bolus. Multiple PMs rapidly appeared as the food moved posteriorly and some of these became greatly thickened in the middle and posterior regions of the midgut. WGA in the diet caused hypersecretion of unorganized PM in the anterior midgut lumen, disintegration of microvilli, and cessation of feeding. It was also shown to bind to both the chitinous network and to several PM proteins, perhaps causing voids in the PM and sparse matrix material. This allowed the passage of food particles through a defective PM into the ectoperitrophic space and penetration into the microvillar brush border. Stimulation of PM secretion and cessation of feeding may have been a response to damage to the brush border. Unlike ECB, the chitinous network of THW is a randomly organized felt‐like structure embedded in a proteinaceous matrix. This PM is secreted as a thin multilayered structure in the anterior region of the midgut, but multiple and thickened PMs occur in the middle and posterior lumens of the midgut. THW tolerated high amounts of WGA in its diet with no disruption of PM formation or inhibition of growth. WGA did accumulate as large masses embedded in the PM, but caused no voids that would allow the penetration of food particles and subsequent damage to the brush border. Therefore, differences in PM formation and structure between ECB and THW appeared to affect how WGA interacts with chitinous and proteinaceous components of the PM and subsequent effects on larval feeding and growth. Arch. Insect Biochem. Physiol. 47:100–109, 2001. © 2001 Wiley‐Liss, Inc.
Therapeutic effects of acetylsalicylic acid in giant cell arteritis
Authors: Weyand Cornelia M. , Kaiser Markus , Yang Hongyu , Younge Brian , Goronzy Jörg J.
Published: August 2002

Objective

In giant cell arteritis (GCA), inflammatory lesions typically produce interferon‐γ (IFNγ)– and nuclear factor κB (NF‐κB)–dependent monokines. Corticosteroids influence disease activity by repressing NF‐κB–dependent genes but have only marginal effects on IFNγ. The current study explored whether acetylsalicylic acid (ASA) had cytokine‐repressing activity in GCA and could function as a steroid‐sparing agent.

Methods

Temporal artery–severe combined immunodeficiency (SCID) mouse chimeras were created by engrafting inflamed temporal arteries into SCID mice. Chimeras were treated with ASA, indomethacin, or dexamethasone for 3 weeks. Temporal artery grafts were harvested and cytokine message was semiquantified by polymerase chain reaction–enzyme‐linked immunosorbent assay. The ability of dexamethasone and ASA to suppress IFNγ and interleukin‐1β (IL‐1β) messenger RNA and protein production was also tested in vitro using T cell clones and monocytes derived from patients with GCA. Drug‐induced effects on the transcription factors NF‐κB and activator protein 1 (AP‐1) were assessed by electrophoretic mobility shift assays (EMSAs).

Results

At clinically relevant doses, 20–100 mg/kg, ASA was a highly effective inhibitor of cytokine transcription in temporal arteries. While dexamethasone preferentially targeted NF‐κB–regulated monokines, ASA acted predominantly by suppressing IFNγ. Indomethacin failed to reduce tissue IFNγ transcription, which therefore excluded the inhibition of cyclooxygenases as a critical mechanism. IFNγ production by T cell clones was highly sensitive to ASA‐mediated suppression, whereas IL‐1β production by lipopolysaccharide‐stimulated monocytes responded primarily to dexamethasone. The combination of ASA and dexamethasone had synergistic effects. EMSAs demonstrated that ASA interfered with the formation of AP‐1, whereas dexamethasone suppressed the nuclear translocation of NF‐κB.

Conclusion

The results of this study provide evidence of the complementary action of ASA and corticosteroids in suppressing proinflammatory cytokines in the vascular lesions of GCA.
Testing visual information retrieval methodologies case study: Comparative analysis of textual, icon, graphical, and “spring” displays
Authors: Morse Emile , Lewis Michael , Olsen Kai A.
Published: August 2002

Although many different visual information retrieval systems have been proposed, few have been tested, and where testing has been performed, results were often inconclusive. Further, there is very little evidence of benchmarking systems against a common standard. An approach for testing novel interfaces is proposed that uses bottom‐up, stepwise testing to allow evaluation of a visualization, itself, rather than restricting evaluation to the system instantiating it. This approach not only makes it easier to control variables, but the tests are also easier to perform. The methodology will be presented through a case study, where a new visualization technique is compared to more traditional ways of presenting data.
Strategic help in user interfaces for information retrieval
Authors: Brajnik Giorgio , Mizzaro Stefano , Tasso Carlo , Venuti Fabio
Published: August 2002

Although no unified definition of the concept of search strategy in Information Retrieval (IR) exists so far, its importance is manifest: nonexpert users, directly interacting with an IR system, apply a limited portfolio of simple actions; they do not know how to react in critical situations; and they often do not even realize that their difficulties are due to strategic problems. A user interface to an IR system should therefore provide some strategic help, focusing user's attention on strategic issues and providing tools to generate better strategies. Because neither the user nor the system can autonomously solve the information problem, but they complement each other, we propose a collaborative coaching approach, in which the two partners cooperate: the user retains the control of the session and the system provides suggestions. The effectiveness of the approach is demonstrated by a conceptual analysis, a prototype knowledge‐based system named FIRE, and its evaluation through informal laboratory experiments.
Bioequivalence assessment of Azomycin® (Julphar, UAE) as compared to Zithromax® (Pfizer, USA)—two brands of azithromycin—in healthy human volunteers
Authors: Najib Naji M. , Idkaidek Nasir , Ghanem Iz‐Eddein , Admour Isra' , Mahmood Alam S. , Zaman Q. , Dham Ruwayda
Published: August 2002

Two studies have been performed to assess the relative bioavailability of Azomycin® (Julphar, UAE) as compared with Zithromax® (Pfizer, USA) at the International Pharmaceutical Research Center (IPRC), Amman, Jordan. One study involved Azomycin® capsules and the other Azomycin® suspension. Each study enrolled 24 volunteers and in both studies, after an overnight fasting, the two brands of azithromycin were administered as single dose on two treatment days separated by a 2 weeks washout period. After dosing, serial blood samples were collected for a period of 192 h. Plasma harvested from blood, was analysed for azithromycin by HPLC coupled with electrochemical detection. Various pharmacokinetic parameters including AUC0–t, AUC0–∞, Cmax, Tmax, T1/2 and Kelm were determined from plasma concentrations for both formulations and found to be in good agreement with the reported values. AUC0–t, AUC0–∝ and Cmax were tested for bioequivalence after log‐transformation of data. No significant difference was found based on ANOVA; 90% confidence intervals for the test/reference ratios of these parameters were found within the bioequivalence acceptance range of 80–125%. Based on these statistical inferences it was concluded that Azomycin® capsule is bioequivalent to Zithromax® capsule and Azomycin® suspension is bioequivalent to Zithromax® suspension. Copyright © 2001 John Wiley & Sons, Ltd.
Cryo‐electron microscopy as an investigative tool: the ribosome as an example
Authors: Frank Joachim
Published: August 2002

Cryo‐electron microscopy allows the visualization of macromolecules in their native state. Combined with techniques of three‐dimensional reconstruction, cryo‐EM images of single molecules can be used to study macromolecular interactions. The ribosome, a large RNA–protein complex with multiple binding interactions, is an excellent test case illustrating the power of these new techniques. Conformational changes during the binding of tRNA and protein factors to the ribosome can now be studied without the interference of crystal packing. Now that the first X‐ray structures of ribosomal subunits have become available, conformational changes observed by cryo‐EM in different functional states can be traced back to internal rearrangements of the underlying structural framework. Electron microscopy, X‐ray crystallography, and modeling should be used together in the endeavor to understand the functioning of the translational machinery. BioEssays 23:725–732, 2001. © 2001 John Wiley & Sons, Inc.
Treatment of self‐injury correlated with mechanical restraints
Authors: Kahng SungWoo , Abt Kimberly A. , Wilder David A.
Published: August 2002

Mechanical arm restraints were used to decrease hand‐to‐head self‐injurious behavior (SIB) exhibited by a 16‐year‐old female with severe mental retardation. Although mechanical restraints reduced hand‐to‐head SIB, they were correlated with an increase in other topographies of SIB (e.g., head banging). These other topographies were not significantly affected by the addition of an environmental enrichment procedure, but were immediately and almost completely suppressed when contingent exercise was added. Copyright © 2001 John Wiley & Sons, Ltd.
Chemiluminescence associated with amino acid oxidation mediated by hypochlorous acid
Authors: Aspée A. , Lissi E. A.
Published: August 2002

Although most amino acids readily react with hypochlorous acid (HOCl), only the reaction involving tryptophan (Trp) produces a measurable chemiluminescence (CL). Most of this luminescence takes place after total consumption of HOCl when the process is carried out in an excess of Trp. The quantum yield of the process is relatively low (2 × 10−8 Einstein/mol HOCl reacted). The luminescence is attributed to free radical‐mediated secondary reactions of the initially produced chloramines. This is supported by experiments showing that the chloramines produced when HOCl reacts with alanine are able to induce Trp chemiluminescence, and that this luminescence is partially quenched by free radical scavengers. The spectral changes and the effect of pH upon the observed luminescence are compatible with light emission from products produced in the free radical oxidation of Trp. Copyright © 2002 John Wiley & Sons, Ltd.
Enhanced transglucosylation/hydrolysis ratio of mutants of Pyrococcus furiosus β‐glucosidase: Effects of donor concentration, water content, and temperature on activity and selectivity in hexanol
Authors: Hansson Therese , Adlercreutz Patrick
Published: August 2002

The transglucosylation reaction catalyzed by wild‐type β‐glucosidase CelB from hyperthermophilic Pyrococcus furiosus and active site mutants (M424K, F426Y, M424K/F426Y) was studied. The conversion of pentyl‐β‐glucoside to hexyl‐β‐glucoside in hexanol was used as a model transglucosylation reaction. Hydrolysis to glucose was a side reaction. The selectivity towards transglucosylation was quantified by the S value defined as follows:

where rS and rH are the initial rates of transglucosylation and hydrolysis and aw and ahex are the thermodynamic activities of water and hexanol. The activity (rates of hydrolysis and transglucosylation) and the selectivity (S value) were measured as a function of pentyl‐β‐glucoside concentration (5–240 mM), water content (1–100% v/v), and temperature (50–95°C). All mutants had lower activity than the wild‐type enzyme, but they had higher selectivity, which means that they provided a higher ratio of transglucosylation product to hydrolysis product. The largest increase in S‐value (2.6 fold) was obtained by the F426Y mutant, which resulted in increased hexyl‐β‐glucoside yield from 56% to 69%. In addition, the F426Y enzyme had higher selectivity over the wide range of temperatures tested. The activity of CelB wild‐type and CelB F426Y increased as a function of water activity (aw), and complete activation by the water was obtained in a two‐phase system with 20% water phase. In contrast to CelB wild‐type, the F426Y mutant had transferase activity as low as aw = 0.29. Surprisingly, the S value increased with increasing water activity up to aw = 0.92. At still higher water content the S value decreased. © 2001 John Wiley & Sons, Inc. Biotechnol Bioeng 75: 656–665, 2001.
Esterification by immobilized lipase in solvent‐free media: Kinetic and thermodynamic arguments
Authors: Sandoval G. , Condoret J. S. , Monsan P. , Marty A.
Published: August 2002

The aim of this study is to characterize, in solvent‐free systems (SFS), the kinetic and thermodynamic performance of batch lipase‐catalyzed esterification. SFS are compared to a conventional organic solvent, n‐hexane. The esterification of oleic acid with ethanol was chosen as a model reaction. The TABEK (thermodynamic activity‐based enzyme kinetics) approach was used to rationally analyze kinetics. Influence of the reaction medium on final conversions was also studied. Several factors, such as initial molar ratio of substrates, reactant availability, initial water content, and quantity of immobilized enzyme, were examined. Special attention was also turned to enzyme stability and reuse after reaction, this last item being a prerequisite in the development of industrial processes. SFS proved to be almost as efficient as n‐hexane from a kinetic and thermodynamic point of view and offered a better volumetric production. © 2002 Wiley Periodicals, Inc. Biotechnol Bioeng 78: 313–320, 2002.