bluuebunny/crossref_metadata_2025_split huggingface dataset:
Direct ab initio dynamics study on the rate constants and kinetic isotope effect for the reactions of H atoms with GeDn(CH3)4−n (n = 1–4)
Authors: Wu Yang , Ding Yi‐Hong , Xiao Jing‐Fa , Li Ze‐Sheng , Huang Xu‐Ri , Sun Chia‐Chung 
Published: October 2002

AbstractDirect ab initio dynamic calculations are performed on the reactions of atomic hydrogen with GeDn(CH3)4−n (n = 1–4) over the temperature range 200–2000 K at the PMP4SDTQ/6‐311 +G(3df,2p)//MP2/6‐31 +G(d) (for n = 2–4) and G2//MP2/6‐31 +G(d) (for n = 1) levels. The corresponding kH/kD ratios are then calculated in order to determine the kinetic isotope effect for the four reactions. For the simplest GeD4 +H reaction, the only one that has available experimental data, the calculated canonical variational transition state theory incorporates small‐curvature tunneling correction (CVT/SCT) thermal rate constants, and the kH/kD values are in good agreement with the experimental values within the experimental temperature range 293–550 K. For the four GeDn(CH3)4−4 (n = 1–4) reactions, the variational effect is small over the whole temperature range, whereas the small‐curvature effect is important in the lower temperature range. Finally, the overall rate constants are fitted to the three‐parameter expression over the whole temperature range 200–2000 K as 5.8 × 108T1.68exp(−929/T), 1.7 × 108T1.80exp(−691/T), 2.58 × 108T1.71exp(−706/T), and 1.0 × 107T2.08exp(−544/T) cm3 mol−1 s−1 for the n = 4, 3, 2, and 1 reactions. Our work may represent the first theoretical study of the kinetic isotope effect for the H‐attack on the GeH bonding. © 2002 Wiley Periodicals, Inc. J Comput Chem 23: 1366–1374, 2002
Neuromodulation of arthropod mechanosensory neurons
Authors: Torkkeli Päivi H. , Panek Izabela 
Published: October 2002

AbstractArthropod mechanosensory afferents have long been known to receive efferent synaptic connections onto their centrally located axon terminals. These connections cause presynaptic inhibition by attenuating the action potentials arriving at the axon terminals, thus reducing the synaptic potentials in the postsynaptic neurons. This type of inhibition can specifically reduce the excitation of selected postsynaptic neurons while leaving others unaffected. However, recent research has demonstrated that sensory signals detected by arthropod mechanosensory neurons can also be synaptically modulated before they ever arrive at the axon terminals. In arachnids and crustaceans, wide and complex networks of synapses on all parts of the afferent neurons, including the somata and dendrites, provide mechanisms to inhibit or enhance the responses to mechanical stimuli as they are being detected. This modulation will affect the signal transmission to all axonal branches and postsynaptic cells of the affected receptor neuron. In addition to the increased complexity of mechanosensory information transmission produced by these synapses, a variety of circulating neuroactive substances also modulate these neurons by acting on their postsynaptic receptors. Microsc. Res. Tech. 58:299–311, 2002. © 2002 Wiley‐Liss, Inc.
Combined biochemistry and histocytochemistry as a tool to investigate Ecto‐ATPase in the cardiac muscle
Authors: Zinchuk Vadim S. , Okada Teruhiko , Seguchi Harumichi 
Published: October 2002

AbstractEcto‐ATPase (ecto‐adenosine triphosphatase), a key enzyme of cardiac metabolism, is responsible for modulation of the concentration of extracellular nucleotides in the heart. We present methodology consisting of the combined use of biochemical and histocytochemical techniques to study its properties. Using samples from essentially the same preparation, we applied biochemistry and histocytochemistry to determine biochemical characteristics of ecto‐ATPase and an in situ localization of its reactivity. Our results indicated that detected enzyme resists fixation, depends on divalent ions, and hydrolyzes ATP, but not AMP or ADP‐β‐S. Reaction product of the enzyme activity was found confined to the extracellular surface of the plasma membrane of cardiac myocytes and endothelial cells due to the corresponding orientation of the enzyme active sites. Experiments using an inhibitor justified specificity of the reaction. When used together with molecular biological and immunocytochemical techniques, the present methodological approach should be capable of yielding important information about the actual ability of ecto‐ATPase to operate. Microsc. Res. Tech. 58:427–431, 2002. © 2002 Wiley‐Liss, Inc.
Aminoglycoside‐derived cationic lipids as efficient vectors for gene transfection in vitro and in vivo
Authors: Belmont Philippe , Aissaoui Abderrahim , Hauchecorne Michelle , Oudrhiri Noufissa , Petit Laure , Vigneron Jean‐Pierre , Lehn Jean‐Marie , Lehn Pierre 
Published: October 2002

AbstractBackgroundCationic lipids are at present very actively investigated for gene transfer studies and gene therapy applications. Basically, they rely on the formation of DNA/lipid aggregates via electrostatic interactions between their cationic headgroup and the negatively charged DNA. Although their structure/activity relationships are not well understood, it is generally agreed that the nature of the positive headgroup impacts on their transfection activity. Thus, we have directed our efforts toward the development of cationic lipids with novel cationic moieties. In the present work, we have explored the transfection potential of the lipophilic derivatives of the aminoglycoside kanamycin A. Indeed, aminoglycosides, which are natural polyamines known to bind to nucleic acids, provide a favorable scaffold for the synthesis of a variety of cationic lipids because of their structural features and multifunctional nature.Methods and resultsWe report here the synthesis of a cationic cholesterol derivative characterized by a kanamycin A headgroup and of its polyguanidinylated derivative. The amino‐sugar‐based cationic lipid is highly efficient for gene transfection into a variety of mammalian cell lines when used either alone or as a liposomal formulation with the neutral phospholipid dioleoylphosphatidylethanolamine (DOPE). Its polyguanidinylated derivative was also found to mediate in vitro gene transfection. In addition, colloidally stable kanamycin‐cholesterol/DOPE lipoplexes were found to be efficient for gene transfection into the mouse airways in vivo.ConclusionsThese results reveal the usefulness of cationic lipids characterized by headgroups composed of an aminoglycoside or its guanidinylated derivative for gene transfection in vitro and in vivo. Copyright © 2002 John Wiley & Sons, Ltd.
Gutted adenoviral vector growth using E1/E2b/E3‐deleted helper viruses
Authors: Barjot Catherine , Hartigan‐O'Connor Dennis , Salvatori Giovanni , Scott Jeannine M. , Chamberlain Jeffrey S. 
Published: October 2002

AbstractBackgroundHelper‐dependent, or gutted, adenoviruses (Ad) lack viral coding sequences, resulting in reduced immunotoxicity compared with conventional Ad vectors. Gutted Ad growth requires a conventional Ad to supply replication and packaging functions in trans. Methods that allow high‐titer growth of gutted vectors while reducing helper contamination, and which use safer helper viruses, will facilitate the use of gutted Ad vectors in vivo.MethodsReplication‐defective helper viruses were generated that are deleted for Ad E1, E2b and E3 genes, but which contain loxP sites flanking the packaging signal. Complementing Ad packaging cell lines (C7‐cre cells) were also generated by transfecting 293 cells with the Ad E2b genes encoding DNA polymerase and pre‐terminal protein, and with a cre‐recombinase plasmid.ResultsWe show that C7‐cre cells allow efficient production of gutted Ad using ΔE1 + ΔE2b + ΔE3 helper viruses whose growth can be limited by cre‐loxP‐mediated excision of the packaging signal. Gutted Ad vectors carrying ∼28 kb cassettes expressing full‐length dystrophin were prepared at high titers, similar to those obtained with E2b+ helpers, with a resulting helper contamination of <1%.ConclusionsThese new packaging cell lines and helper viruses offer several significant advantages for gutted Ad vector production. They allow gutted virus amplification using a reduced number of passages, which should reduce the chances of selecting rearranged products. Furthermore, the residual helper contamination in gutted vector preparations should be less able to elicit immunological reactions upon delivery to tissues, since E2b‐deleted vectors display a profound reduction in viral gene expression. Copyright © 2002 John Wiley & Sons, Ltd.
Antiretroviral drug resistance among HIV‐1 infected children failing treatment
Authors: Mullen Jane , Leech Susan , O'Shea Siobhan , Chrystie Ian L. , du Mont Gillian , Ball Colin , Sharland Michael , Cottam Fiona , Zuckerman Mark , Rice Philip , Easterbrook Philippa 
Published: October 2002

AbstractHigh levels of HIV‐1 replication occur following perinatal infection and antiretroviral drugs may not fully suppress viral load during the early years of childhood. Adherence to treatment may also be difficult among children. These two factors will contribute to development of drug resistance but limited paediatric data are available. This study has, therefore, evaluated the prevalence of drug resistance among children and assessed the contribution of adherence to failing therapy. Samples from 26 children who had experienced virological failure to antiretroviral therapy were tested for drug resistance using the Visible Genetics TRUGENE™ HIV‐1 genotyping assay. HIV‐1 subtype was determined using a peptide‐based EIA and drug adherence determined by physician assessment. Twenty‐four children were black African, 23 of whom were infected with a non‐B subtype. HIV RNA sequence data was obtained for 21 of the 26 children; at treatment failure resistance mutations were detected in the protease gene of 7 (33%) and the reverse transcriptase gene of 19 (90%). A lower proportion of children had evidence of drug resistance at nadir and no resistance mutations were detected prior to treatment. Genotypic resistance was common in those treated with lamivudine (10/11, 91%), nevirapine (6/8, 75%), and zidovudine (7/11, 64%). The prevalence of mutations was lower among those receiving other nucleoside reverse transcriptase inhibitors and protease inhibitors. In 50% of children, drug adherence was >90%. Antiretroviral drug resistance was common among this group of children failing therapy, the majority of whom were infected with non‐B subtypes of HIV‐1. As adherence to treatment was low in 50%, this was likely to be an important contributory factor. J. Med. Virol. 68:299–304, 2002. © 2002 Wiley‐Liss, Inc.
Antibody responses to Epstein‐Barr virus‐encoded latent membrane protein‐1 (LMP1) and expression of LMP1 in juvenile Hodgkin's disease
Authors: Meij Pauline , Vervoort Marcel B.H.J. , Bloemena Elisabeth , Schouten Tabitha E. , Schwartz Cindy , Grufferman Seymour , Ambinder Richard F. , Middeldorp Jaap M. 
Published: October 2002

AbstractA large group of juvenile Hodgkin's disease patients (n = 242, mean age 11.7 years, 75% [n = 181] seropositive) was evaluated for anti‐Epstein‐Barr virus (EBV) antibody responses and the presence of EBV‐encoded EBER‐RNA and latent membrane protein‐1 (LMP1)‐protein expression in the tumor. The molecular diversity of anti‐EBV antibody responses in Hodgkin's disease patients with EBV‐positive and‐negative tumors was studied by enzyme‐linked immunosorbent assay (ELISA) and immunoblot. Using purified recombinant LMP1 protein as antigen, the presence of antibodies to LMP1 was related to expression of LMP1 in the tumor cells and specific EBV‐serological patterns. Antibodies to LMP1 were detected in 30% of the EBV‐seropositive Hodgkin's disease patients. The presence of antibodies to LMP1 was not associated with a distinct anti‐EBV antibody diversity profile (ELISA), but a significantly higher percentage of patients with antibodies to LMP1 had antibodies to ZEBRA and viral capsid antigen (VCA)‐p18 (Immunoblot). Significantly more patients with an EBV‐positive tumor had detectable antibody responses to LMP1, but the presence of antibodies to LMP1 did not reflect the expression of LMP1 protein in the tumor cells. Interestingly, all patients with the strongest antibody responses to LMP1 had EBV‐negative tumors, suggesting immunological selection in vivo. J. Med. Virol. 68:370–377, 2002. © 2002 Wiley‐Liss, Inc.
Enhancing the antitumoral effect of hypericin‐mediated photodynamic therapy by hyperthermia
Authors: Chen Bin , Roskams Tania , de Witte Peter A.M. 
Published: October 2002

AbstractBackground and ObjectivesIn the previous study, we have found a synergistic effect on the RIF‐1 tumor cell killing when hypericin‐mediated photodynamic therapy (PDT) was combined with hyperthermia. The purpose of the present study was to investigate the antitumoral effect of hypericin‐PDT in combination with hyperthermia in the RIF‐1 mouse tumor model.Study Design/Materials and MethodsTumor response to PDT in combination with hyperthermia was compared to the response to PDT or hyperthermia alone. To explore the possible mechanism involved in the interaction of PDT and hyperthermia, we determined the tumor cell survival by in vivo/in vitro cell survival assay and analyzed the functional blood vessels by Hoechst 33342 staining. The mode of cell death was examined by TUNEL assay.ResultsEnhanced tumor response was obtained by PDT immediately followed by hyperthermia. Tumor cell survival assay revealed that indirect vascular effect contributed greatly to the overall tumor cell death induced by PDT with hypericin, whereas direct tumor cytotoxicity played a major role in hyperthermia‐induced tumor cell killing. Combining PDT with hyperthermia brought about a synergistic interaction on direct tumor cell killing. Even though PDT or hyperthermia alone induced severe blood vessel shutdown and the combined treatments led to significant potentiation of the vascular damage as examined by Hoechst staining, the gain in tumor cell death as a result of this secondary vascular effect was limited after the combined treatments. Following the cellular damage by PDT in combination with hyperthermia, tumor cells were triggered to undergo apoptosis.ConclusionsOur study demonstrated the possibility of using hyperthermia to potentiate the antitumoral effect of hypericin‐mediated PDT. Lasers Surg. Med. 31:158–163, 2002. © 2002 Wiley‐Liss, Inc.
The body consumed: Reflexivity and cosmetic surgery
Authors: Askegaard Søren , Gertsen Martine Cardel , Langer Roy 
Published: October 2002

AbstractWe live in a time with increasing focus on the body and its perfection. The marketing environment is replete with products and services catering to the health, well‐being, and beauty of bodies and, it is implied, of our souls. One of the more drastic and consequently also much debated and, at times, tabooed type of service and consumption within this field is cosmetic surgery. This article is based on interviews with 15 women who have had cosmetic operations. It examines what motivated their decision to have surgery; some of their thoughts and feelings before, during and after the process; and the ways in which the operation has influenced their life and self‐identity subsequently. The material is analysed within a theoretical framework resting mainly on Anthony Giddens' work on self‐identity in late modernity. This implies that cosmetic surgery is understood to be part of the individual's reflexive construction of self‐identity, and leads to a focus on issues such as self‐determination, self‐esteem, and the relationship between body and identity. Finally, some relations between self‐identity and the marketing institution are discussed. © 2002 Wiley Periodicals, Inc.
Customer familiarity and its effects on satisfaction and behavioral intentions
Authors: Söderlund Magnus 
Published: October 2002

AbstractWhen customer familiarity increases, customer expertise is likely to increase. Although expertise is known to affect information processing in several ways, few studies have examined the effects of familiarity on customers' evaluations and behavioral intentions. In this study, it was found that a high level of prepurchase familiarity was associated with more extreme (i.e., more polarized) postpurchase responses in customer satisfaction, repurchase intentions, and word‐of‐mouth intentions compared to a low prepurchase level of familiarity. More specifically, when service performance was high, high‐familiarity customers expressed a higher level of satisfaction and behavioral intentions than did less familiar customers. On the other hand, when performance was low, high‐familiarity customers expressed lower levels of satisfaction and behavioral intentions than did low‐familiarity customers. © 2002 Wiley Periodicals, Inc.
Structure and expression of the follicle‐stimulating hormone receptor gene in a marsupial, Macropus eugenii
Authors: Mattiske D. , Pask A.J. , Shaw J.M. , Shaw G. 
Published: October 2002

AbstractFollicle stimulating hormone (FSH) is essential for folliculogenesis. The function of FSH is mediated through its receptor (FSHr) and modulation of the receptor is thought to be the mechanism by which the responsiveness of follicles to gonadotrophins is regulated. FSHr is alternatively spliced to produce several transcripts in all eutherian species studied. However, controversy exists over the significance of alternatively spliced transcripts. In this study, we cloned and characterised the tammar wallaby (Macropus eugenii) FSHr gene and examined its expression. Comparison of gene structure and function between marsupials and eutherians enables identification of conserved features that are likely to be of functional significance. Tammar FSHr shares 94% amino acid similarity with human FSHr and is expressed in both the adult testis and ovary suggesting a similar function for this gene in both marsupials and eutherians. Tammar FSHr undergoes alternate splicing to produce four transcripts consistent with the splice variants seen in eutherians. These results strongly suggest that alternate splicing is of functional significance in the ovary since it has remained a highly conserved character of this gene for over 100 million years of divergent evolution.Mol. Reprod. Dev. 63: 24–31, 2002. © 2002 Wiley‐Liss, Inc.
The epidemiology of developmental disabilities in low‐income countries
Authors: Durkin Maureen 
Published: October 2002

AbstractAlthough most of the world's children live in developing countries and may be at high risk for disability, very little is known about the prevalence and causes of developmental disabilities in these countries. This paper discusses methodological difficulties contributing to this lack of knowledge, and provides an overview of what is known about the epidemiology of developmental disabilities in low‐income countries. At least some forms of developmental disability appear to be more common in low‐income countries than in wealthier countries, despite the probability of higher mortality among children with disabilities in low‐income countries. For example, most studies of severe mental retardation in low‐income countries report prevalences greater than 5 per 1,000 children, while prevalence estimates from industrialized countries are consistently below this. Major risk factors for developmental disabilities in some low‐income countries include specific genetic diseases, a higher frequency of births to older mothers, consanguinity, and specific micronutrient deficiencies and infections. Trauma and toxic exposures are also important risk factors, but their contributions to the etiology of developmental disabilities in low‐income countries are not well documented. Though many of the causes of developmental disabilities are understood and preventable, proven methods of prevention are not being fully implemented in developing countries. Epidemiologic studies are needed to raise awareness of the public health impacts of developmental disabilities in low‐income countries and to provide a basis for setting priorities and designing efficient interventions. MRDD Research Reviews 2002;8:206–211. © 2002 Wiley‐Liss, Inc.
Psychometric characteristics of dyspnea descriptor ratings in emergency department patients with exacerbated chronic obstructive pulmonary disease
Authors: Parshall Mark B. 
Published: October 2002

AbstractThe purpose of this study was to evaluate the reliability, content validity, and factor structure of dyspnea sensory quality descriptor ratings in emergency department (ED) patients with exacerbated chronic obstructive pulmonary disease (COPD). During an ED visit 104 patients with COPD rated the intensity of 16 dyspnea sensory quality descriptors (numerical ratings of 0–10) in relation to how they felt when they decided to come to the ED (Decision) and 1 week before the visit. Content validity of 15 descriptors was supported. Factor analysis of Decision ratings resulted in seven descriptors and three factors (α=.88; 74% common variance): Smothering/Suffocating/Hunger for air (α=.87); Effort/Work (α=.87); and Tight/Constricted (α=.74). Results indicate that the intensity of sensory quality descriptors can be measured reliably in COPD patients during an exacerbation of COPD. The initial descriptor list of descriptors could be cut by more than half while retaining satisfactory psychometric properties. © 2002 Wiley Periodicals, Inc. Res Nurs Health 25:331–344, 2002
Spine length measurement in the first trimester of pregnancy
Authors: De Biasio P. , Ginocchio G. , Vignolo M. , Ravera G. , Venturini P. L. , Aicardi G. 
Published: October 2002

AbstractObjectivesThe aim of the study was to evaluate spine length as an indicator of skeletal growth in the first trimester of pregnancy and to provide a nomogram of spine length at the end of the first trimester of pregnancy.MethodsThe study was carried out on 420 single pregnancies, at gestational ages ranging from 11 to 14 weeks, using high‐resolution transabdominal echography. Biparietal diameter and crown–rump length (CRL) were measured to date the pregnancy. Using the same scanning plane used to measure CRL, the whole spine length in antero‐dorsal position can be visualized as a double hyperechoic line from 10 weeks of gestation onwards. Spine length was measured three times by one observer and the mean of the three measurements was considered as definitive. Forty fetuses had multiple measurements for interobserver and intraobserver error analysis.ResultsLinear relationship between spine length, and gestational age, biparietal diameter and CRL were demonstrated. Spine length (millimetres) as a function of gestational age (days) was expressed by the regression equation: spine length = 1.09 × (gestational age in days) −60.56, with a determination coefficient of R2 = 0.744. Spine length ranged from 21.5 mm at 11 weeks to 41.9 mm at 14 weeks.ConclusionThe data obtained showed that spine length increased progressively from the end of the first trimester to the beginning of the second. A high correlation between spine length, gestational age, biparietal diameter, and CRL was observed. Spine length measurement could therefore be considered a good indicator of fetal growth. Copyright © 2002 John Wiley & Sons, Ltd.