bluuebunny/crossref_metadata_2025 huggingface dataset:
Memory for events after twenty years
Authors: White Richard
Published: October 2002

This is a study of one person's memory for events that occurred twenty years earlier. Memory was observed to follow an asymptotic rate of decay. No experience of recovered memories occurred. Factors found to be related to recall were the rarity of the event, its vividness, and the emotional intensity experienced at the time. Factors unrelated or only weakly related were perceived importance of the event, its association with knowledge, and intensities of physical sensations. Pleasant events were recalled a little better than unpleasant. Though less strongly associated with memory than is location, moderate marking of events with date and time was found. The results suggest that personal memory declines as the images of events one by one submerge into the mass of generalized experiences. The more vivid, rare, and emotional experiences are more likely to remain discriminable, and may be sustained by rehearsal. Copyright © 2002 John Wiley & Sons, Ltd.
Work‐related cumulative trauma disorders of the upper extremity: Navigating the epidemiologic literature
Authors: Zakaria Dianne , Robertson James , MacDermid Joy , Hartford Kathleen , Koval John
Published: October 2002

Background

Cumulative trauma disorder of the upper extremity (CTDUE) is an umbrella term used to describe disorders resulting from repeated use of the upper extremity over time rather than a specific incident. The primary purpose of this article is to summarize the literature regarding the rate of work‐related CTDUE, while drawing attention to the various factors contributing to the wide range of reported findings.

Methods

The Cumulative Index to Nursing and Allied Health and Medline databases were searched for articles focusing on etiology or rates of occurrence of work‐related CTDUE and their findings were summarized.

Results

Potential reasons for rising rates, a gender differential, and the substantial range in rates and rate ratios are delineated and important factors to consider when interpreting rates derived from workers' compensation data are detailed.

Conclusions

Future research should attempt to correctly identify more specific categories of CTDUE in well‐defined and accurately‐quantified “at risk” populations to provide more meaningful information regarding the epidemiology of CTDUE and the effectiveness of control activities. Am. J. Ind. Med. 42:258–269, 2002. © 2002 Wiley‐Liss, Inc.
Novel mutation of TBX3 in a Japanese family with Ulnar‐Mammary syndrome: Implication for impaired sex development
Authors: Sasaki Goro , Ogata Tsutomu , Ishii Tomohiro , Hasegawa Tomonobu , Sato Seiji , Matsuo Nobutake
Published: October 2002

We report on a Japanese family (two brothers and their mother) with ulnar‐mammary syndrome (UMS). Clinical features included hypoplasia or aplasia of upper limbs on the ulnar side in the three affected individuals, micropenis with or without cryptorchidism, and hypoplastic nipples in the brothers; and hypoplastic mammary glands and nipples, poor perspiration, and bicornuate uterus in the mother. Endocrine studies performed for the underdeveloped external genitalia when the brothers were 11 6/12 and 7 2/12 years old, respectively, indicated low to low‐normal responses of luteinizing hormone (LH) and follicle stimulating hormone (FSH) to gonadotropin releasing hormone stimulation tests (elder brother: LH = < 0.2 → 2.2 IU/L, FSH = 0.6 → 2.2 IU/L; younger brother: LH = < 0.2 → 3.3 IU/L, FSH = 0.7 → 4.4 IU/L) and normal testosterone responses to human gonadotropin stimulation tests (elder brother: < 0.5 → 8.8 nmol/L; younger brother: < 0.5 → 6.3 nmol/L). Testosterone enanthate therapy (25 mg/dose IM twice) was effective in the brothers, with penile length increase being similar between the brothers (∼5 mm/dose) and 23 age‐matched boys with idiopathic micropenis (mean 4.4 mm/dose, range 2.5–7.5 mm/dose). Sequence analysis of the TBX3 gene showed a novel heterozygous nonsense mutation (A817T, K273X) in exon 4 of the three patients. The results are consistent with the previous finding that UMS is caused by haploinsufficiency of TBX3, and imply that mild gonadotropin deficiency may be the primary cause for underdeveloped external genitalia in males with UMS. © 2002 Wiley‐Liss, Inc.
Refinement of the autosomal recessive polycystic kidney disease (PKHD1) interval and exclusion of an EF hand‐containing gene as aPKHD1candidate gene
Authors: Onuchic Luiz F. , Mrug Michal , Hou Xiaoying , Eggermann Thomas , Bergmann Carsten , Zerres Klaus , Avner Ellis D. , Furu Laszlo , Somlo Stefan , Nagasawa Yasuyuki , Germino Gregory G. , Guay‐Woodford Lisa M.
Published: October 2002

Autosomal recessive polycystic kidney disease (ARPKD) is an often devastating form of polycystic kidney disease that presents primarily in infancy. The locus,PKHD1(polycystic kidney and hepatic disease 1), on chromosome 6p21.1–p12, has been linked to all classical forms of this disorder. In previous studies, we cloned thePKHD1interval in a set of overlapping YACs, converted this YAC‐based framework into a BAC/PAC contig, and delimited the critical interval to a region flanked by the markersD6S1714andD6S1024. We now have refined the genetic interval using new polymorphic markers developed from our BAC/PAC resources. In addition, we have evaluated a recently identified, EF hand‐containing gene that maps to the interval of interest, established its transcript sequence, defined its genomic organization, and excluded this new gene as aPKHD1candidate. Therefore, this study has narrowed thePKHD1interval and excluded a potentially relevant gene as aPKHD1candidate gene. This further refinement of thePKHD1interval will facilitate efforts to identify thePKHD1gene by positional cloning. These data also provide additional, highly polymorphic markers for haplotype‐based diagnostic testing for ARPKD. © 2002 Wiley‐Liss, Inc.
Association between the TNFα‐308 A/G polymorphism and the onset‐age of Alzheimer disease
Authors: Alvarez Victoria , Mata Ignacio F. , González Pelayo , Lahoz Carlos H. , Martínez Carmen , Peña Joaquín , Guisasola Luis M. , Coto Eliecer
Published: October 2002

Local inflammatory processes associated with amyloid plaques would contribute to the progression of late‐onset Alzheimer disease (LOAD). Tumor necrosis factors α (TNFα) and β (LTα) are inflammatory cytokines involved in the local immune response occurring in the central nervous system of LOAD patients. Genetic variation at these genes could contribute to the risk of developing AD or influence the age at the onset of the disease. We genotyped 315 LOAD patients and 400 healthy controls for DNA‐polymorphisms in the genes encoding TNFα (‐308 G/A, ‐238G/A) and LTα (Asn26Thr). Carriers of ‐308A showed a mean age at onset 3 years younger than noncarriers of this allele (P = 0.019). Our data suggest an effect of the TNFα‐308 polymorphism on the age at onset of late AD. This represents additional evidence of the importance of genetic variation at the proinflammatory components in the origin and progression of this common neurodegenerative disease. © 2002 Wiley‐Liss, Inc.
Gender‐specific molecular heterosis of dopamine D2 receptor gene (DRD2) for smoking in schizophrenia
Authors: Lee Hong‐Seock , Kim Seung‐Hyun , Lee Heon‐Jeong , Kim Leen , Lee Sang‐Kyu , Jang Dong‐Won , Lee Min Soo , Son Bong‐Gi , Suh Kwang‐Yoon , Kim Sangduk
Published: October 2002

We examined the genetic effect of DRD2 A1 allele in 167 Korean schizophrenics in relation to their smoking habit. Although there was no apparent difference in the genotype distributions of DRD2 gene among the female schizophrenics (n = 66), the male counterpart (n = 101) showed significant differences in their genotype distributions. The comparison between male smoking and non‐smoking patients showed the difference in genotype distribution (P = 0.010) with a higher prevalence of A1 allele (P = 0.020) and frequency of heterozygotes (P = 0.005), but not frequency of the A1 allele. The A1A2 heterozygotes male showed significantly higher smoking rate compared to the A1A1 or A2A2 homozygotes male, and non‐smokers were deficient in heterozygotes. By contrast, among female schizophrenics, the heterozygotes showed a lower smoking rate than homozygotes and there were more heterozygotes in non‐smokers. The deviation from Hardy‐Weinberg expectations was observed in male and female non‐smokers showing quite opposite profiles. Highly significant differences were seen between male and female non‐smokers in A1 prevalence (P = 0.001), genotype distribution (P = 0.00011), and frequency of heterozygotes (P = 0.00003), but not in A1 frequency. The analyses from both male and female as one group showing no significant difference in the genotype distributions between smokers and non‐smokers could be explained by the gender difference in the genetic effect of DRD2 A1 allele. Our findings present the gender‐specific molecular heterosis of DRD2 gene in relation specifically to the smoking status of schizophrenic patients. They indicate the importance of heterosis and gender effects that should be taken into consideration for the association studies. © 2002 Wiley‐Liss, Inc.
Attachment and social preferences in cooperatively‐reared cotton‐top tamarins
Authors: Kostan Karen M. , Snowdon Charles T.
Published: October 2002

In many primate species a close attachment between mother and infant provides a secure base for the infant when the infant is frightened or under stress. In cooperatively breeding primates infant carrying is divided among several individuals in the group, with the mother often doing little more than nursing. In these species it is not clear which individual would best serve as a secure base for the infant. We studied eight infant cotton‐top tamarins from birth through 20 weeks of age, noting who carried the infant during the first 100 days, who transferred food with the infants, and, as infants became independent, with whom they associated during social play and affiliative behavior. From week 9 to week 20, when infants were independent of carriers most of the time, we presented families with six trials (once every 2 weeks) with a threatening stimulus (a human dressed in a lab coat and wearing an animal mask). Infants played primarily with their twin or youngest sibling and had affiliative interactions with many family members. However, in fearful situations, infants ran to those who had carried them and transferred food with them the most–their father or oldest brother (never to the mother). Although adults increased rates of mobbing calls in response to the threat, infants significantly reduced their vocalization rate. For these cooperatively breeding monkeys, the attachment object for infants is the family member that invested the most effort in carrying the infant and transferring food with the infant. These results parallel and extend results from bi‐parental infant care species in which the father serves as the primary attachment figure. © 2002 Wiley‐Liss, Inc.
Comparison of responses to alarm calls by patas (Erythrocebus patas) and vervet (Cercopithecus aethiops) monkeys in relation to habitat structure
Authors: Enstam Karin L. , Isbell Lynne A.
Published: October 2002

We studied responses to alarm calls of sympatric patas (Erythrocebus patas) and vervet (Cercopithecus aethiops) monkeys in relation to habitat structure, with the intention of understanding the relationship between the environment and predator avoidance. Patas and vervet monkeys are phylogenetically closely related and overlap in body size. However, while patas monkeys are restricted to nonriverine habitats at our study site, vervets use both nonriverine and riverine habitats, allowing us to “vary” habitat structure while controlling for effects of group size, composition, and phylogeny. Patas monkeys in the nonriverine habitat responded to mammalian predator alarm calls with a greater variety of responses than did vervets in the riverine habitat, but not when compared with vervets in the nonriverine habitat. Ecological measurements confirm subjective assessments that trees in the riverine habitat are significantly taller and occur at lower densities than trees in the nonriverine habitat. Despite the lower density of trees in the riverine habitat, locomotor behavior of focal animals indicates that canopy cover is significantly greater in the riverine than the nonriverine habitat. Differences in responses to alarm calls by the same groups of vervets in different habitat types, and convergence of vervets with patas in the same habitat type, suggest that habitat type can be a significant source of variation in antipredator behavior of primates. Am J Phys Anthropol 119:3–14, 2002. © 2002 Wiley‐Liss, Inc.
Creutzfeldt‐Jakob disease cluster in an Australian rural city
Authors: Collins Steven , Boyd Alison , Fletcher Ashley , Kaldor John , Hill Andrew , Farish Stephen , McLean Catriona , Ansari Zahid , Smith Margaret , Masters Colin L.
Published: October 2002

Through the Australian National Creutzfeldt‐Jakob Disease Registry, 6 pathologically confirmed sporadic cases were recognized over a 13‐year period in persons who had been long‐term residents of a moderate‐sized rural city, whereas the expected number was 0.923. An extensive investigation could not find any point‐source or case‐to‐case transmission links. This occurrence is highly statistically significant (p = 0.0027) when viewed in isolation and remains significant (p < 0.02) when only the cases that arose after the cluster was recognized were taken into account. However, a more conservative statistical analysis suggests that such a grouping could have arisen by chance in at least one population group of this size when the whole country is taken into consideration.
Acute hyperglycemia adversely affects stroke outcome: A magnetic resonance imaging and spectroscopy study
Authors: Parsons Mark W. , Barber P. Alan , Desmond Patricia M. , Baird Tracey A. , Darby David G. , Byrnes Graham , Tress Brian M. , Davis Stephen M.
Published: October 2002

Controversy exists whether acute hyperglycemia is causally associated with worse stroke outcome or simply reflects a more severe stroke. In reversible ischemia models, hyperglycemia is associated with lactic acidosis and conversion of penumbral tissue to infarction. However, the relationship between hyperglycemia, lactic acidosis, and stroke outcome has not been explored in humans. Sixty‐three acute stroke patients were prospectively evaluated with serial diffusion‐weighted and perfusion‐weighted magnetic resonance imaging and acute blood glucose measurements. Patients with hypoperfused at‐risk tissue were identified by acute perfusion‐diffusion lesion mismatch. As a substudy, acute and subacute magnetic resonance spectroscopy was performed in the 33 most recent patients to assess the relationship between acute blood glucose and lactate production in the ischemic region. In 40 of 63 patients with acute perfusion‐diffusion mismatch, acute hyperglycemia was correlated with reduced salvage of mismatch tissue from infarction, greater final infarct size, and worse functional outcome. These correlations were independent of baseline stroke severity, lesion size, and diabetic status. Furthermore, higher acute blood glucose in patients with perfusion‐diffusion mismatch was associated with greater acute‐subacute lactate production, which, in turn, was independently associated with reduced salvage of mismatch tissue. In contrast, acute blood glucose levels in nonmismatch patients did not independently correlate with outcome measures, nor was there any acute‐subacute increase in lactate in this group. Acute hyperglycemia increases brain lactate production and facilitates conversion of hypoperfused at‐risk tissue into infarction, which may adversely affect stroke outcome. These findings support the need for randomized controlled trials of aggressive glycemic control in acute stroke.
Magnetization transfer imaging in normal aging, mild cognitive impairment, and Alzheimer's disease
Authors: Van Der Flier Wiesje M. , Van Den Heuvel Dominique M. J. , Weverling‐Rijnsburger Annelies W. E. , Bollen Eduard L. E. M. , Westendorp Rudi G. J. , Van Buchem Mark A. , Middelkoop Huub A. M.
Published: October 2002

The purpose of this study was to assess whether structural brain damage as detected by volumetric magnetization transfer imaging (MTI) is present in mild cognitive impairment (MCI) and Alzheimer's disease (AD) and, if so, whether these abnormalities are global in character or restricted to the temporal lobe. Volumetric MTI analysis of the whole brain and temporal and frontal lobes was performed in 25 patients with probable AD, in 13 patients with MCI, and in 28 controls. Magnetization transfer ratio (MTR) histograms were produced, from which we derived measures for structural brain damage and atrophy. The peak heights of the MTR histograms of MCI and AD patients were lower than those of controls for the whole brain and temporal and frontal lobes, reflecting structural brain damage. AD patients had more atrophy than controls in all regions that were studied. MCI patients differed from controls for temporal lobe atrophy only. Volumetric MTI demonstrates structural changes that are related to cognitive decline in large parts of the brain of AD patients. Moreover, structural changes also were observed in MCI patients, indicating that widespread brain damage can be demonstrated before patients are clinically demented.
Comparative degradation data of polyesters and related poly(ester amide)s derived from 1,4‐butanediol, sebacic acid, and α‐amino acids
Authors: Montané J. , Armelin E. , Asín L. , Rodríguez‐Galán A. , Puiggalí J.
Published: October 2002

Two new sequential poly(ester amide)s (PEAs) derived from 1,4‐butanediol, sebacic acid, and L‐alanine (PABA8) or glycine (PGBG8) are prepared and characterized. For comparative purposes the related polyesters (PEs) 4,10 and 6,10 are also studied. The calorimetric analysis shows that the inclusion of amino acids improves the thermal properties such as the melting temperature without a significant reduction in their thermal stability. All polymers show hydrolytic and enzymatic degradability. The degradation rates of the PEAs are higher for the alanine derivative (PABA8) because of its low crystallinity and the higher specificity of the essayed proteolytic enzymes. The PEs are only degraded faster when enzymes with esterase activity are employed. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 85: 1815–1824, 2002
Fourier transform infrared photoacoustic studies of the adsorption behavior of poly(2‐hydroxypropyl methacrylate) at solid–liquid interface
Authors: Pekel Nursel , Güven Olgun
Published: October 2002

Adsorption of poly(2‐hydroxypropyl methacrylate) on alumina from dimethylformamide was studied by ultraviolet (UV) and Fourier transform infrared (FT‐IR) photoacoustic spectroscopy (FTIR PA) techniques. Adsorbent amount and concentration effects were investigated. The adsorption results are in conformity with Langmuir's isotherm. The differences observed in Langmuir parameters were explained by polymer–polymer, polymer–solvent, polymer–adsorbent, and solvent–adsorbent interactions. The fraction of carbonyl groups attached to the surface of alumina was calculated with a curve‐fitting computer program. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 85: 2750–2756, 2002
Flavin‐grafted poly(vinyl alcohol): Preparation and properties
Authors: Sanjust Enrico , Cocco Dina , Curreli Nicoletta , Rescigno Antonio , Sollai Francesca , Bannister Joe Victor
Published: October 2002

An NAD(P)H oxidase‐like activity was found in semisynthetic flavoadducts, prepared from an aldehyde derivative of riboflavin and commercial poly(vinylalcohol) (PVA), previously grafted with aminopropyl side chains. Both water‐soluble and water‐insoluble beaded preparations were obtained. The products showed a noticeable NAD(P)H oxidase‐like activity, converting the nucleotide substrate to its oxidized counterpart NAD(P)+ at the expense of molecular oxygen, the latter being reduced to hydrogen peroxide. In contrast to some “true” β‐NAD(P)H oxidases, the PVA adducts do not require the presence of additional flavin adenine dinucleotide (FAD) to work; some properties of the flavoadducts were studied that make these flavoadducts good candidates for technological applications. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 85: 2471–2477, 2002
Dynamically vulcanized nitrile rubber/polypropylene thermoplastic elastomers
Authors: Zhang Xiangfu , Huang Hua , Zhang Yinxi
Published: October 2002

A new compatibilized method was used to prepare thermoplastic elastomer (TPE) of nitrile rubber (NBR) and polypropylene (PP) with excellent mechanical properties by dynamic vulcanization. Glycidyl methacrylate (GMA) grafted PP/amino‐compound was used as a compatibilizer. The effects of the curing systems, compatibilizer, PP type, and reprocessing on the mechanical properties of NBR/PP thermoplastic elastomers were investigated in detail. Experimental results showed that the addition of amino‐compound in the compatibilzer can significantly increase the mechanical properties of the NBR/PP thermoplastic elastomer. Compared with other amino‐compounds, diethylenetriamine (DETA) has the best effect. PP with higher molecular weight is more suitable for preparing NBR/PP thermoplastic elastomer with high tensile strength and high elongation at break. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 85: 2862–2866, 2002
Preparation and properties of poly(methyltrifluoropropylsiloxane‐b‐imide) copolymer. I
Authors: Kang Doo Whan , Kim Young Min
Published: October 2002

Poly(methyltrifluoropropylsiloxane‐block‐imide) copolymers (PSBPI), containing various contents of fluorosiloxane, were prepared by the thermal imidization of 3,3′,4,4′‐benzophenonetetracarboxylic dianhydride (BTDA), 4,4′‐oxydianiline (ODA), and α,ω‐aminopropyl‐terminated poly(methyltrifluoropropylsiloxane) prepolymer (APMFS). APMFS was prepared from an equilibrium polymerization of (3,3,3‐trifluoropropyl)methylcyclotrisiloxane (D3Me,CH2,CH2,CF3) with 1,3‐bis(3‐aminopropyl)‐1,1,3,3‐tetramethyldisiloxane in the presence of the tetramethylammoniumhydroxide (TMAH) catalyst. The content of APMFS, in the reaction mixture, was varied from 0 to 30 wt % of diamine. The structure of copolymer was confirmed by FTIR spectroscopy. The thermal stability, linear coefficient of thermal expansion, modulus, X‐ray pattern, and other properties, such as surface enrichment behavior and solubility, were investigated. PSBPI exhibited relatively low crystallinity regardless of the APMFS content in the copolymer. On the other hand, thermogravimetric, thermomechanical, dynamic mechanical, and surface properties were affected by the content of APMFS segment in the copolymer backbone. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 85: 2867–2874, 2002
Preparation, physico‐chemical characterization, and optical analysis of polyvinyl alcohol‐based films suitable for protected cultivation
Authors: De Prisco Nicola , Immirzi Barbara , Malinconico Mario , Mormile Pasquale , Petti Lucia , Gatta Giuseppe
Published: October 2002

The use of biodegradable polymer films for mulching is a topic of great interest both from the environmental point of view and for the intrinsic properties that the above films, when appropriately designed, might have. In the present article we report on a synthetic approach that, starting from existing biodegradable polymers, leads to a new material characterized by a time‐controlled biodegradation. The idea that subsides is to bridge polyvinyl alcohol (PVOH) chains through polycaprolactone (PCL) crosslinks. In such a way, PVOH looses its water sensitivity and can stand on the ground for the time needed for the mulching to occur, while the PCL crosslinks, being sensitive to (slow) fungal attack, will undergo cleavage, followed by the complete bio‐assimilation of the residual PVOH chains. The number of crosslinks introduced can control time of biodegradation. The polymers are characterized in their intrinsic chemical‐physical properties, while a preliminary evaluation of their efficiency as mulches is obtained through the analysis of their thermal behavior when deposited on an irrigated soil. The results are also compared with a model approach able to predict the thermal behavior of a film in specific environmental conditions. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 86: 622–632, 2002
Predicting the reactivity of phenolic compounds with formaldehyde. II. Continuation of an ab initio study
Authors: Mitsunaga Tohru , Conner Anthony H. , Hill Charles G.
Published: October 2002

Phenol–formaldehyde resins are important adhesives used by the forest products industry. The phenolic compounds in these resins are derived primarily from petrochemical sources. Alternate sources of phenolic compounds include tannins, lignins, biomass pyrolysis products, and coal gasification products. Because of variations in their chemical structures, the reactivities of these phenolic compounds with formaldehyde vary in quite subtle ways. Previously, it was demonstrated that the reactivity of a number of phenols with formaldehyde in nonaqueous conditions could be correlated with charges calculated for reactive sites on the aromatic ring (Conner, A. H. J Appl Polym Sci 2000, 78, 355–363). We studied the reactivity of a larger number of phenolic compounds with formaldehyde in an aqueous solution using sodium hydroxide as the catalyst. Reaction rates were determined from measurements of the concentrations of the phenolic compounds and formaldehyde as functions of time. The reaction rate constants varied over a wide range (approximately 10−2 to 104 L mol−1 h−1). An estimate of the reactivity per reactive site on the phenolic ring was determined by dividing the rate by the number of reactive sites. Atomic charges for each phenolic compound were calculated by ab initio methods at the RHF/6‐31+ G level of theory using the CHelpG method. The charge per reactive site was estimated by summing the charges at all the reactive sites on the phenolic ring and dividing by the number of reactive sites. A strong correlation was observed between the reactivity per reactive site and the average charge per reactive site. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 86: 135–140, 2002
Solubility of carbon dioxide in polyethylene/titanium dioxide composite under high pressure and temperature
Authors: Areerat Surat , Hayata Yusuke , Katsumoto Ryuichi , Kegasawa Tadahiro , Egami Hideo , Ohshima Masahiro
Published: October 2002

Solubility of carbon dioxide (CO2) in a low‐density polyethylene (LDPE)/titanium dioxide (TiO2) composite was measured using a magnetic suspension balance (MSB) at a temperature from 423 to 473 K and pressures up to 15 MPa. The effect of the TiO2 concentration on the solubility is investigated by varying TiO2 content in the range of 0–20 wt %. Extending the Sanchez–Lacombe equation of state and its mixing rule for binary mixture, a scheme of calculating CO2 solubility in composite from MSB data is developed. The solubility of CO2 in the composites increases in proportion to pressure and exponentially decreases with temperature. The apparent solubility, which is defined by the weight of dissolved CO2 per unit weight of the composite, decreases as the TiO2 content increases. However, the true solubility, which can be defined by the weight of dissolved CO2 per unit weight of polymer, is constant, although the TiO2 content is changed. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 86: 282–288, 2002
Permeation of H2, N2, CH4, C2H6, and C3H8 through asymmetric polyetherimide hollow‐fiber membranes
Authors: Wang Dongliang , Teo W. K. , Li K.
Published: October 2002

Permeation properties of pure H2, N2, CH4, C2H6, and C3H8 through asymmetric polyetherimide (PEI) hollow‐fiber membranes were studied as a function of pressure and temperature. The PEI asymmetric hollow‐fiber membrane was spun from a N‐methyl‐2‐pyrrolidone/ethanol solvent system via a dry‐wet phase‐inversion method, with water as the external coagulant and 50 wt % ethanol in water as the internal coagulant. The prepared asymmetric membrane exhibited sufficiently high selectivity (H2/N2 selectivity >50 at 25°C). H2 permeation through the PEI hollow fiber was dominated by the solution‐diffusion mechanism in the nonporous part. For CH4 and N2, the transport mechanism for gas permeation was a combination of Knudsen flow and viscous flow in the porous part and solution diffusion in the nonporous part. In our analysis, operating pressure had little effect on the permeation of H2, CH4, and N2. For C2H6 and C3H8, however, capillary condensation may have occurred at higher pressures, resulting in an increase in gas permeability. As far as the effect of operating temperature was concerned, H2 permeability increased greatly with increasing temperature. Meanwhile, a slight permeability increment with increasing temperature was noted for N2 and CH4, whereas the permeability of C2H6 and C3H8 decreased with increasing temperature. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 86: 698–702, 2002
Graft copolymerization of styrene and acrylonitrile onto EPDM
Authors: Qu Xiongwei , Shang Shurui , Liu Guodong , Zhang Liucheng
Published: October 2002

Acrylonitrile–EPDM–styrene (AES) graft copolymers were synthesized by solution graft polymerization of styrene (St) and acrylonitrile (AN) onto EPDM in an n‐hexane/benzene solvent with benzoyl peroxide (BPO) as an initiator. The structure changes were studied by an FTIR spectrophotometer. The grafting parameters were calculated gravimetrically. The influence of the polymerization conditions, such as the reaction time, concentration of the initiator, EPDM content, and weight ratio of St/AN, on the structure of the products was investigated. It was found that a proper initiator concentration and EPDM content will give a high grafting ratio of the AES resin. The thermal property of the copolymer was studied using programmed thermogravimetric analysis (TGA). The results showed that the copolymer has a better heat‐resistant property than that of ABS, especially for the initial decomposition temperature (Tin) and the maximum weight loss rate temperature (Tmax). Also, the mechanism of the graft reaction was discussed. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 86: 428–432, 2002
Complete discontinuity of the distal fistula tract from the developing gut: Direct histologic evidence for the mechanism of tracheoesophageal fistula formation
Authors: Spilde Troy L. , Bhatia Amina M. , Marosky Julie K. , Hembree Mark J. , Kobayashi Hiroyuki , Daume Erica L. , Prasadan Krishna , Manna Pradip , Preuett Barry L. , Gittes George K.
Published: October 2002

The embryogenesis of tracheoesophageal anomalies remains controversial. The purpose of this study was to better define the embryogenesis of developing esophageal atresia with tracheoesophageal fistula (EA/TEF), with specific attention to the controversial issue of whether a discontinuity exists in the foregut during its development of EA/TEF. Pregnant outbred rats were injected with adriamycin (2 mg/kg i.p.) on days 6–9 of gestation (E6–E9). At E12.5 and 13.5, microdissection of the entire foregut was performed. Foreguts were examined by phase microscopy, and serial, precisely transverse sections were created for hematoxylin and eosin (H&E) staining. Gross microdissection of the developing foregut at E12.5 (n = 9) revealed a blind‐ending, bulbous fistula tract arising from the middle branch of the tracheal trifurcation (as seen by direct and phase microscopy). No connection with the gut could be appreciated at E12.5, but by E13.5 (n = 10) there was an obvious connection between the fistula and the stomach. Serial H&E transverse sections also demonstrated a blind‐ending fistula tract arising from the trachea at E12.5. This fistula tract was clearly discontinuous from the developing stomach, which appeared much further caudal to the end of the fistula tract. These results strongly support a model of experimental TEF wherein the fistula tract arises from a trifurcation of the trachea, and (only during a specific gestational window between days 12.5 and 13.5) there is discontinuity between the fistula tract and the stomach. By day 13.5, the fistula joins with the stomach anlage. These observations in the developing EA/TEF should help to resolve the controversy about the mechanism of EA/TEF formation. Anat Rec 267:220–224, 2002. © 2002 Wiley‐Liss, Inc.
Investigation of fluoroquinolone‐induced myalgia using 31P magnetic resonance spectroscopy and in vitro contracture tests
Authors: Guis S. , Bendahan D. , Kozak‐Ribbens G. , Mattei J. P. , Le Fur Y. , Confort‐Gouny S. , Figarella‐Branger D. , Jouglard J. , Cozzone P. J.
Published: October 2002

Objective

To investigate muscle function in patients with severe myalgia resulting from fluoroquinolone (FQ) treatment. We used histology, in vitro contracture tests (IVCTs), and 31P magnetic resonance spectroscopy (31P MRS) to explore muscle contraction and metabolism.

Methods

We studied 3 patients with myalgia, hyperalgia tendinopathy, and arthralgia following FQ treatment and 3 normal subjects after taking FQs. Results were compared with those of a control group of 9 subjects free of any muscle disease and not taking FQs. Muscle biopsies were performed on the left biceps, and IVCTs were performed in accordance with the protocol recommended by the European Malignant Hyperthermia Group. 31P MR spectra of forearm flexor muscles were recorded at 4.7T throughout a rest‐exercise‐recovery protocol.

Results

31P MRS showed a significant reduction of pH changes measured at the end of exercise and a faster rate of proton efflux measured during recovery in all patients. IVCTs diagnosed 1 patient as being susceptible to malignant hyperthermia. No specific histologic anomalies were observed in muscle biopsy samples, which showed normal mitochondria.

Conclusion

The adverse effects recorded in the 3 patients are related to a preexisting muscular anomaly revealed by FQ treatment.
The PedsQL™ in pediatric rheumatology: Reliability, validity, and responsiveness of the Pediatric Quality of Life Inventory™ generic core scales and rheumatology module
Authors: Varni James W. , Seid Michael , Smith Knight Tara , Burwinkle Tasha , Brown Joy , Szer Ilona S.
Published: October 2002

Objective

The Pediatric Quality of Life Inventory (PedsQL) is a modular instrument designed to measure health‐related quality of life (HRQOL) in children and adolescents ages 2–18 years. The 23‐item PedsQL 4.0 Generic Core Scales are multidimensional child self‐report and parent proxy‐report scales developed as the generic core measure to be integrated with the PedsQL disease‐specific modules. The 22‐item PedsQL 3.0 Rheumatology Module was designed to measure pediatric rheumatology–specific HRQOL. This study was undertaken to demonstrate the reliability, validity, and responsiveness of the PedsQL 4.0 Generic Core Scales and the PedsQL 3.0 Rheumatology Module in pediatric rheumatology.

Methods

The 4 PedsQL 4.0 Generic Core Scales (physical, emotional, social, and school functioning) and the 5 PedsQL 3.0 Rheumatology Module scales (pain and hurt, daily activities, treatment, worry, and communication) were administered to 231 children and 244 parents (271 subjects accrued overall) recruited from a pediatric rheumatology clinic.

Results

Internal consistency reliability for the PedsQL Generic Core total scale score (α = 0.91 for child self report, α = 0.93 for parent proxy report), physical health summary score (α = 0.87 for child self report, α = 0.89 for parent proxy report), and psychosocial health summary score (α = 0.86 for child self report, α = 0.90 for parent proxy report) were acceptable for group comparisons. The Rheumatology Module scales also demonstrated acceptable reliability for group comparisons (α = 0.75–0.86 for child self report, α = 0.82–0.91 for parent proxy report). Validity was demonstrated using the known‐groups method. The PedsQL distinguished between healthy children and children with rheumatic diseases as a group. The responsiveness of the PedsQL was demonstrated through patient change over time as a result of clinical intervention.

Conclusion

The results demonstrate the reliability, validity, and responsiveness of the PedsQL 4.0 Generic Core Scales and the PedsQL 3.0 Rheumatology Module in pediatric rheumatology.
Risk factors for total hip replacement due to primary osteoarthritis: A cohort study in 50,034 persons
Authors: Flugsrud Gunnar B. , Nordsletten Lars , Espehaug Birgitte , Havelin Leif I. , Meyer Haakon E.
Published: October 2002

Objective

To identify prospectively the possible risk factors for total hip replacement (THR) due to primary osteoarthritis in a large cohort.

Methods

Data from a cardiovascular screening were matched with 9 years of national data on THR. Mean age at the start of followup was 54.9 years, and the 50,034 participants were followed up for an average of 9 years. During followup, 672 persons had a first THR due to primary osteoarthritis.

Results

We found dose‐response associations between body mass index (BMI), body weight, and the level of physical activity at work and THR for primary osteoarthritis. The highest versus the lowest quarter of BMI had a relative risk of 2.0 (95% confidence interval [95% CI] 1.4–2.9) among men and 3.0 (95% CI 2.1–4.1) among women. The highest versus the lowest quarter of body weight had a relative risk of 2.1 (95% CI 1.4–3.2) among men and 3.4 (95% CI 2.4–4.9) among women. Intensive versus sedentary physical activity at work had a relative risk of 2.1 (95% CI 1.5–3.0) among men and 2.1 (95% CI 1.3–3.3) among women. No association was found between physical activity in leisure and THR for primary osteoarthritis.

Conclusion

Intensive physical activity at work and a high BMI each contribute significantly to the overall risk of undergoing THR due to primary osteoarthritis. Lowering the exposure to these risk factors may substantially reduce the need for hip replacement.
Expression of recombination activating genes 1 and 2 in peripheral B cells of patients with systemic lupus erythematosus
Authors: Girschick Hermann J. , Grammer Amrie C. , Nanki Toshihiro , Vazquez Eduardo , Lipsky Peter E.
Published: October 2002

Objective

To analyze immunoregulatory abnormalities in patients with systemic lupus erythematosus (SLE) by assessing the expression of messenger RNA (mRNA) for types 1 and 2 recombination activating genes (RAG) in the peripheral blood of patients with active SLE.

Methods

We examined B cell populations and also individual B cells from patients with SLE for the expression of RAG mRNA.

Results

Analysis of bulk mRNA indicated that RAG1 and RAG2 mRNA were found routinely in peripheral B cells of patients with active SLE, but not in healthy subjects. When assessed on a single‐cell basis, there was a 3‐fold increase in the frequency of RAG1‐ and RAG2‐expressing B cells in SLE patients compared with healthy subjects. Notably, B cells expressing both RAG1 and RAG2 mRNA expressed only IgD mRNA, but not IgG mRNA. Fifty percent of RAG‐expressing B cells also expressed VpreB mRNA, whereas all expressed CD154 mRNA. Phenotypic analysis indicated that RAG‐expressing B cells were activated, mature B cells.

Conclusion

These results indicate that RAG expression is up‐regulated in peripheral IgD+ and VpreB+ B cells of patients with active SLE. These cells may contribute to the immunoregulatory abnormalities in patients with SLE.
Influence of epitopes CD44v3 and CD44v6 in the invasive behavior of fibroblast‐like synoviocytes derived from rheumatoid arthritic joints
Authors: Wibulswas Auragun , Croft Daniel , Pitsillides Andrew A. , Bacarese‐Hamilton Ian , McIntyre Peter , Genot Elisabeth , Kramer IJsbrand M.
Published: October 2002

Objective

To investigate the functional implications of CD44 splice variant expression in fibroblast‐like synoviocytes (FLS) obtained from patients with rheumatoid arthritis (RA).

Methods

FLS were isolated from synovial tissue obtained from both diseased and nondiseased joints. The expression of splice variants containing exons v3 and v6 was analyzed using immunocytochemistry with exon‐specific antibodies and reverse transcription–polymerase chain reaction followed by Southern blotting. The invasive capacity of the cells was studied in a transwell invasion assay.

Results

FLS obtained from RA joints expressed various CD44 splicing combinations containing the variant exons v3 and/or v6. These cells were highly invasive, whereas cells from normal tissues, which lacked expression of CD44 splice variants, were not. Variant exons CD44v3 and CD44v6 were instrumental in matrix invasion in vitro, with cells enriched for CD44v3 and v6 exhibiting greater invasion and antibodies that specifically recognize CD44v3 and v6 abrogating this capacity to invade. Invasive cells showed a reduced expression of CD44v7/8, and antibodies against this epitope had no significant effect on cellular infiltration of the matrix. The antibodies had no effect on cell migration into the porous section of the transwell.

Conclusion

FLS obtained from patients with RA express CD44 splice variants and are highly invasive, whereas cells obtained from healthy tissue do not express these variants and are not invasive. Expression of the epitopes CD44v3 and CD44v6 is instrumental in the invasive capacity but not in cell migration. This finding highlights a functional implication for the expression of CD44 splice variants at the level of matrix degradation.
Physician treatment preferences in rheumatoid arthritis of differing disease severity and activity: The impact of cost on first‐line therapy
Authors: Erkan Doruk , Yazici Yusuf , Harrison Melanie J. , Paget Stephen A.
Published: October 2002

Objective

To conduct a pilot study to identify rheumatologists' treatment preferences for first‐line rheumatoid arthritis (RA) therapy and determine whether pharmacoeconomic variables modify physician choice(s).

Methods

A questionnaire describing 3 different RA scenarios was mailed to American College of Rheumatology members within 4 geographic regions of the US. Physicians were asked to identify their choice(s) of first‐line therapy for each of the cases, first taking cost into consideration, second without considering the influence of cost, and third identifying the therapy that would be chosen for either themselves or a family member.

Results

Three hundred seventy‐five questionnaires out of a total of 994 (37.7%) were returned between 3/12/00 and 4/25/00. Hydroxychloroquine was the most commonly cited medication for a mild disease activity/severity presentation, and methotrexate for a moderate‐to‐severe disease activity/severity presentation. For the severe disease activity/severity presentation, when cost was not considered, 217 (65%) rheumatologists included new disease‐modifying antirheumatic drugs (leflunomide, etanercept, and infliximab) in their choice of first‐line agents; this number decreased to 47 (14%) when cost was a consideration.

Conclusion

Pharmacoeconomics appear to play a dominant role in rheumatologists' choice of treatment regimens, at times contrary to the physician's perception of the effectiveness of a drug. Future studies should address physician preferences in more depth with respect to cost and its various components.
Systemic lupus erythematosus in three ethnic groups. X. Measuring cognitive impairment with the cognitive symptoms inventory
Authors: Alarcón Graciela S. , Cianfrini Leanne , Bradley Laurence A. , Sanchez Martha L. , Brooks Kemi , Friedman Alan W. , Baethge Bruce A. , Fessler Barri J. , Bastian Holly M. , Roseman Jeffrey M. , McGwin Gerald , Reveille John D. ,   for the Lumina Study Group
Published: October 2002

Objective

To determine the factor structure of the Cognitive Symptoms Inventory (CSI) in patients with systemic lupus erythematosus (SLE) participating in a multiethnic longitudinal study of outcome, the Lupus in Minority populations, Nature versus nurture (LUMINA) study.

Methods

LUMINA patients of Hispanic (n = 48), African American (n = 64), and Caucasian (n = 44) ethnicity who had a study visit (enrollment or followup) between January 1 and September 30, 2000 were included. Patients completed the CSI, a 21‐item self‐report measure of cognitive function. Sociodemographic, clinical, immunologic, psychosocial, and behavioral variables were ascertained per protocol and as previously described. Data were analyzed with SPSS. The factor structure of the CSI was determined using the principal axis method with oblique rotation as decided by Gorsuch. All factors having an Eigenvalue greater than 1 were considered. A 4‐factor solution was derived that accounted for 42.6% of the common variance. The correlations between patient factor scale scores and variables from the demographic, clinical, psychosocial, and behavioral domains were then examined.

Results

The four factors and their respective variance are, Attention/Concentration (28.8%), Pattern Recognition/Activity Management (5.7%), Intermediate Memory (4.7%), and Initiation of Executive Functions (3.4%); each factor correlated with the total CSI score. Overall, patients' factor scale scores were positively and significantly correlated with other measures of cognitive dysfunction such as the Systemic Lupus Activity Measure (neuromotor domain) or the Systemic Lupus International Collaborating Clinics Damage Index (neurocognitive impairment), as well as with measures of fatigue, maladaptive coping skills, poor mental functioning, poor social support, and helplessness. They were, however, not correlated with sociodemographic or clinical variables.

Conclusions

In addition to demonstrating that the CSI can be used to measure cognitive impairment in patients with SLE in the research setting, we have determined a 4‐factor solution for the CSI that appears to have adequate metric properties. At present, the CSI may best be used as a screen for difficulties in daily activities involving intermediate memory, concentration, attention, and executive function. Nevertheless, further work with the CSI items and factor scales is necessary to establish internal and test–retest reliability of the factor scales; and provide additional evidence of the convergent and predictive validity of these scales in larger samples of patients from each ethnic subgroup.
The determinants of change in tibial cartilage volume in osteoarthritic knees
Authors: Wluka Anita E. , Stuckey Stephen , Snaddon Judith , Cicuttini Flavia M.
Published: October 2002

Objective

The rate of change in osteoarthritic (OA) tibial articular cartilage and the factors that influence it are not known. We examined a cohort of subjects with OA to determine the change in articular knee cartilage volume over the course of 2 years and to identify factors which might influence such change and its rate.

Methods

One hundred twenty‐three subjects with OA underwent baseline knee radiography and magnetic resonance imaging (MRI) on their symptomatic knee. They were followed up 2 years later with a repeat MRI of the same knee. Knee cartilage volume was measured at baseline and at followup. Risk factors assessed at baseline were tested for their association with change in knee cartilage volume over time.

Results

Mean ± SD total tibial articular cartilage decreased by 5.3 ± 5.2% (95% confidence interval [95% CI] 4.4%, 6.2%) per year. The annual percentages of loss of medial and lateral tibial cartilage were 4.7 ± 6.5% (95% CI 3.6%, 5.9%) and 5.3 ± 7.2% (95% CI 4.1%, 6.6%), respectively. Initial cartilage volume was the most significant determinant of loss of tibial cartilage in all compartments, while age was a significant determinant of lateral tibial cartilage loss, when possible confounders were accounted for.

Conclusion

In OA, tibial cartilage volume is lost at a rate of ∼5% per year. The main factor affecting cartilage loss is initial cartilage volume. Our results suggest that cartilage loss may be more rapid early in disease. Further study is required to determine whether the rate of cartilage loss in OA is steady or phasic, and to identify factors amenable to intervention to reduce cartilage loss.