bluuebunny/crossref_metadata_2025_split huggingface dataset:
In vivo modulation of a cortical functional sensory representation shortly after topical cholinergic agent application
Authors: Penschuck Silke , Chen‐Bee Cynthia H. , Prakash Neal , Frostig Ron D. 
Published: October 2002

AbstractThe aim of the present study was to determine whether cholinergic increase in the size of a functional representation (collective evoked response from a large population of neurons) can be observed shortly (within an hour) after treatment onset and whether nicotinic receptors can participate in this type of modulation. Cholinergic agonist application has been found previously to increase the response of a single cortical neuron to a stimulus. Also, pairing cholinergic basal forebrain stimulation with delivery of a tone has been reported to increase the size of that tone's functional representation. Whereas the increase in a single cortical neuron response can occur within seconds after cholinergic agonist application, to date the increase in the size of a functional representation has only been investigated within one to several weeks after the onset of pairing basal forebrain stimulation with tone delivery. Furthermore, primarily muscarinic receptors have been implicated in these types of changes in cortical activity. By using optical imaging of intrinsic signals in vivo, we found that the size of a whisker's functional representation in the primary somatosensory cortex of the rat increases substantially within 69 or 46 minutes after topical application of either a muscarinic or nicotinic agonist to the exposed cortex, respectively, and decreases within 23 minutes after topical application of a muscarinic antagonist. For each cholinergic agent, we verified that delivery of a cholinergic agent by means of topical application can lead to the agent's successful penetration through the cortical layers in the time allotted to complete an imaging experiment. Furthermore, the time course of penetration for each agent was characterized. Based on the combined imaging/penetration results, we speculate on potential sites of cholinergic action in the cortex. Irrespective of the exact mechanism of action, we demonstrate here that an increase in the size of a functional sensory representation can occur shortly by means of activation of either nicotinic or muscarinic receptors. J. Comp. Neurol. 452:38–50, 2002. © 2002 Wiley‐Liss, Inc.
A note on the equivalence of two recent time‐integration schemes for N‐body problems
Authors: Graham E. , Jelenić G. , Crisfield M. A. 
Published: October 2002

AbstractThis paper investigates the relationship between the energy‐ and momentum‐conserving time‐integration scheme of Simo and Gonzalez (Papers—American Society of Mechanical Engineers—All Series, 1993; 93(4)) and a momentum‐conserving time‐integration scheme due to Betsch and Steinmann (Int. J. Numer. Meth. Engng 2000; 49: 599) for N‐body problems. The schemes are shown to be identical if the potential energy of interaction between masses is a polynomial function of the distances between the masses, of degree two or lower. In addition, they are shown to recover the same relative equilibria. Copyright © 2002 John Wiley & Sons, Ltd.
Application of triangular differential quadrature to problems with curved boundaries
Authors: Zhong Hongzhi 
Published: October 2002

AbstractThe recently proposed concept of triangular differential quadrature is consolidated and extended to curvilinear triangles. First, a unit isosceles right triangle is taken as a standard triangle on which all derivatives are expressed in accordance with the triangular differential quadrature rule. Geometric transformations in which the basis functions for determination of weighting coefficients in the triangular differential quadrature are employed to map an arbitrary curvilinear triangle onto the standard triangle are introduced. A simple example is provided to validate the present strategy. Copyright © 2002 John Wiley & Sons, Ltd.
Novel stability criteria for bidirectional associative memory neural networks with time delays
Authors: Liao Xiaofeng , Yu Juebang , Chen Guanrong 
Published: October 2002

AbstractIn this paper, the bidirectional associative memory (BAM) neural network with axonal signal transmission delay is considered. This model is also referred to as a delayed dynamic BAM model. By combining a number of different Lyapunov functionals with the Razumikhin technique, some sufficient conditions for the existence of a unique equilibrium and global asymptotic stability of the network are derived. These results are fairly general and can be easily verified. Besides, the approach for the analysis allows one to consider several different types of activation functions, including piecewise linear sigmoids with bounded activations as well as C1‐smooth sigmoids. It is believed that these results are significant and convenient in the design and applications of BAM neural networks. Copyright © 2002 John Wiley & Sons, Ltd.
EVA: a better TCP version for resource‐insufficient networks
Authors: Li Jung‐Shian , Ma Chung‐Wen 
Published: October 2002

AbstractTCP Vegas exhibits unfair congestion avoidance mechanism, which aggravates when there are insufficient network resources to accommodate buffer space of a pipe (bandwidth delay product). To remedy this shortcoming, we propose an Enhanced VegAs (EVA) that employs three auxiliary mechanisms: Δ revision, congestion detection and congestion tendency detection. A 2kfactorial design with replications is used to study the effect of the three mechanisms. Our results show that TCP EVA achieves better performance than Vegas under various network conditions. Furthermore, congestion avoidance schemes, such as TCP EVA, perform much better than congestion control schemes, such as TCP Reno, in resource‐insufficient networks. Copyright © 2002 John Wiley & Sons, Ltd.
Standard measures of executive function in predicting instrumental activities of daily living in older adults
Authors: Bell‐McGinty Sandra , Podell Kenneth , Franzen Michael , Baird Anne D. , Williams Michael J. 
Published: October 2002

AbstractObjectiveThe purpose of this study was to examine the ability of specific, commonly used neuropsychological tests of executive function to predict functional status among a group of elderly subjects.MethodsFifty study participants underwent a brief neuropsychological evaluation of executive functions and assessment of instrumental activities of daily living (IADL).ResultsA multiple stepwise regression analysis indicated that executive function tests accounted for 54% of the variance in functional status. An examination of the standardized regression coefficients revealed that Trail Making Test‐Part B and the Wisconsin Card Sorting Test were the only two of the five executive function tests that significantly predicted functional status. These executive function measures contributed significantly to the prediction of functional status even after statistically controlling for age, sex, and education.ConclusionThus, the common clinical measures of executive function are useful in predicting functional status in older adults. Copyright © 2002 John Wiley & Sons, Ltd.
Psychotropics among the home‐dwelling elderly—increasing trends
Authors: Linjakumpu T. , Hartikainen S. , Klaukka T. , Koponen H. , Kivelä S.‐L. , Isoaho R. 
Published: October 2002

AbstractObjectiveTo assess the level of and changes in the use of psychotropics among the home‐dwelling elderly in the 1990s.MethodsA descriptive analysis based on data from two cross‐sectional interview and health examination surveys of elderly persons aged 64 years or over conducted in Lieto, a typical semi‐rural Finnish municipality, in 1990–91 and 1998–99. National prescription data were utilized to compare the use of psychotropics in the late 1990s by all Finnish home‐dwelling elderly and the elderly in Lieto. In Lieto drug information was obtained from 1131 persons in 1990–91 and from 1197 in 1998–99, and the mean age of the informants was 73 years in both surveys. The brand names of the prescription drugs (both irregular and regular medication) taken by each interviewee during seven days prior to the interview were recorded and categorized by the Anatomical Therapeutic Chemical (ATC) classification system.ResultsEvery fourth person was taking at least one psychotropic drug in both surveys. Most users were on regular psychotropic medication. The use of hypnotics and antidepressants increased most during the study period. Polypharmacy and the use of psychotropics were most prevalent among those aged 85 years or over, with women predominating. Concomitant use of two or more psychotropics increased statistically significantly from 7% to 10% between the surveys. The young elderly, aged 64–71 years, used cyclic antidepressants equally commonly in both surveys. None of the young elderly used new atypical antipsychotics in 1998–99.ConclusionsPsychotropics tend to be overprescribed and overused among the elderly, a group at the highest risk of adverse drug reactions. The tendency of prescribing for the elderly is not going in a better direction. New‐generation psychotropics were not used. The need for long‐standing use of psychotropics should be assessed regularly. Copyright © 2002 John Wiley & Sons, Ltd.
Nutrition and pharyngeal cancer: Results from a case‐control study in Spain
Authors: Uzcudun Ana Escribano , Retolaza Iñaki Rabanal , Fernández Pilar Bravo , Sánchez Hernández José Javier , Grande Antonio García , García Alfredo García , Olivar Lara Miralles , de Diego Sastre Ignacio , Barón Manuel González , Bouzas José Gavilán 
Published: October 2002

AbstractBackgroundOropharyngeal and hypopharyngeal cancer is increasing all over the world, frequently affecting more and more women and younger individuals and not only the typical 50‐ to 60‐year‐old heavy smoker and drinking man. In addition, 5‐year overall survival rate remains poor (30% to 40% in most series), despite advances in treatment. Therefore, it is crucial to understand as accurately as possible the risk factors for these malignancies to improve primary prevention.MethodsWe report the results from a case‐control study of pharyngeal cancer risk factors conducted in Spain involving 232 consecutive patients who were gender‐ and age‐matched with 232 controls. Data were collected by interviewer‐administered personal interview.ResultsOur results show that low intake of fruit, fruit juice, uncooked vegetables, dietary fiber–containing foods (legume and cereals), fish, milk, and dairy products is an independent risk factor for pharyngeal cancer and that high consumption of meat and fried foods also increases the risk once data are adjusted for tobacco smoking and alcohol drinking.ConclusionsAlthough findings for fruit, juice, and uncooked vegetables are in accordance with those from other authors and can be explained on a biologic basis, the relationship between pharyngeal cancer and dietary excess of saturated fatty acids needs experimental investigation. Findings for milk, dairy products, and fish also warrant more detailed epidemiologic research because of conflicting data reported in the literature and because of the reportedly ambiguous role of retinol in human cancers. No conclusive explanations for the protective effect of dietary fiber–containing foods can be put forward today. Our results are uniquely attributable to oropharyngeal and hypopharyngeal cancers because of the small size of our nasopharyngeal cancer subsample. © 2002 Wiley Periodicals, Inc. Head Neck 24: 830–840, 2002
Lipopolysaccharide‐induced metastatic growth is associated with increased angiogenesis, vascular permeability and tumor cell invasion
Authors: Harmey Judith H. , Bucana Corazon D. , Lu Weixin , Byrne Anne Marie , McDonnell Susan , Lynch Conor , Bouchier‐Hayes David , Dong Zhongyun 
Published: October 2002

AbstractEndotoxin/lipopolysaccharide (LPS), a cell wall component of Gram‐negative bacteria, is a potent inflammatory stimulus. We previously reported that LPS increased the growth of experimental metastases in a murine tumor model. Here, we examined the effect of LPS exposure on key determinants of metastasis—angiogenesis, tumor cell invasion, vascular permeability, nitric oxide synthase (NOS) and matrix metalloproteinase 2 (MMP2) expression. BALB/c mice bearing 4T1 lung metastases were given an intraperitoneal (i.p.) injection of 10 μg LPS or saline. LPS exposure resulted in increased lung weight and incidence of pleural lesions. LPS increased angiogenesis both in vivo and in vitro. Vascular permeability in lung tissue was increased 18 hr after LPS injection. LPS increased inducible nitric oxide synthase (iNOS) and MMP2 expression in lung tumor nodules. 4T1 cells transfected with green fluorescent protein (4T1‐GFP) were injected via lateral tail vein. LPS exposure resulted in increased numbers of 4T1‐GFP cells in mouse lung tissue compared to saline controls, an effect blocked by the competitive NOS inhibitor, NG methyl‐L‐arginine (NMA). LPS‐induced growth and metastasis of 4T1 experimental lung metastases is associated with increased angiogenesis, vascular permeability and tumor cell invasion/migration with iNOS expression implicated in LPS‐induced metastasis. © 2002 Wiley‐Liss, Inc.
A population‐based prospective study of Chlamydia trachomatis infection and cervical carcinoma
Authors: Wallin Keng‐Ling , Wiklund Fredrik , Luostarinen Tapio , Ångström Tord , Anttila Tarja , Bergman Frank , Hallmans Göran , Ikäheimo Irma , Koskela Pentti , Lehtinen Matti , Stendahl Ulf , Paavonen Jorma , Dillner Joakim 
Published: October 2002

AbstractPersistent human papillomavirus (HPV) infection is an established cause of cervical cancer, but the role of other sexually transmitted agents, most notably Chlamydia trachomatis, has not been well defined. The women participating in the population‐based cervical cancer screening program in Västerbotten county of Northern Sweden were followed up for up to 26 years to identify 118 women who developed cervical cancer after having had a normal Pap smear (on average 5.6 years later; range 0.5 months–26 years). As controls, we selected another 118 women who were matched by birth cohort, time‐point of sampling of the baseline normal smear and who had a normal smear at the time when the corresponding case was diagnosed with cancer. The Pap smears and cervical cancer biopsies were analyzed by PCR for C. trachomatis DNA and for HPV DNA. At baseline, C. trachomatis DNA was present in 8% of cases but not among any one of the controls. The relative risk for cervical cancer associated with past C. trachomatis infection, adjusted for concomitant HPV DNA positivity, was 17.1 (95% CI 2.6–∞).The presence of C. trachomatis and of HPV were not interrelated. Whereas C. trachomatis was primarily found in specimens taken many years before cancer diagnosis, HPV DNA was associated with a short lag time before cancer diagnosis. Whereas most women who were HPV DNA‐positive in the prediagnostic smear were also positive for the same virus in the cervical cancer biopsy, none of the women were positive for C. trachomatis in both the prediagnostic smear and in the subsequent cervical cancer. In conclusion, a prior cervical C. trachomatis infection was associated with an increased risk for development of invasive cervical cancer. © 2002 Wiley‐Liss, Inc.
In vivo evaluation of 188Re‐labeled alpha‐melanocyte stimulating hormone peptide analogs for melanoma therapy
Authors: Miao Yubin , Owen Nellie K. , Whitener Donna , Gallazzi Fabio , Hoffman Timothy J. , Quinn Thomas P. 
Published: October 2002

AbstractThe purpose of our study was to optimize melanoma tumor uptake of 188Re‐CCMSH and reduce its nonspecific kidney retention. Nephrotoxicity is often a serious problem associated with targeted radiotherapy, therefore, increasing the tumor/kidney uptake ratio of 188Re‐CCMSH is crucial for optimizing its therapeutic efficacy. Structural modification of the peptide and amino acid co‐infusion were investigated as strategies to improve the tumor/kidney uptake ratio of 188Re‐CCMSH. The substitution of Lys11 with Arg11 was examined to determine if removal of lysine from the peptide would improve kidney clearance without sacrificing tumor uptake. The pharmacokinetics of 188Re‐CCMSH and 188Re‐(Arg11)CCMSH were determined in B16/F1 murine melanoma‐bearing C57 mice. Tumor uptake values of 188Re‐CCMSH and 188Re‐(Arg11)CCMSH were 15.03 ± 5.20% ID/g and 20.44 ± 1.91% ID/g at 1 hr postinjection and 1.94 ± 0.47% ID/g and 3.50 ± 2.32% ID/g at 24 hr postinjection. Renal retention of 188Re‐(Arg11)CCMSH was 11.79 ± 1.29 ID/g and 3.67 ± 0.51 ID/g at 1 hr and 4 hr postinjection, which was a greater than 50% reduction compared to 188Re‐CCMSH. The Arg for Lys substitution in 188Re‐(Arg11)CCMSH resulted in improved tumor uptake and reduced kidney retention. Renal retention of both 188Re‐CCMSH and 188Re‐(Arg11)CCMSH were significantly reduced by co‐injection of 20 mg of L‐lysine, L‐arginine and a combination of L‐lysine:L‐arginine. Tumor/kidney uptake values for 188Re‐CCMSH and 188Re‐(Arg11)CCMSH were maximally reduced by 52.9% and 46.3%, respectively. However, even with amino acid co‐injection, the tumor/kidney ratio of 188Re‐CCMSH was lower than that of 188Re‐(Arg11)CCMSH. Improved tumor uptake and reduced kidney retention of 188Re‐(Arg11)CCMSH will facilitate targeted irradiation of melanoma tumors while minimizing the dose to the kidneys. © 2002 Wiley‐Liss, Inc.
Cell adhesion on poly(propylene fumarate‐co‐ethylene glycol) hydrogels
Authors: Tanahashi Kazuhiro , Mikos Antonios G. 
Published: October 2002

AbstractWe synthesized poly(propylene fumarate‐co‐ethylene glycol) block copolymers [P(PF‐co‐EG)] that were crosslinked to form hydrogels and investigated the effect of copolymer composition on cell adhesion to the hydrogels. These copolymers were water soluble when the molar ratio of ethylene glycol repeating unit to propylene fumarate repeating unit was higher than 4.4. The water content of swollen hydrogels increased from 29 to 63% and the water contact angle decreased from 38 to 21° as the molar ratio increased from 0.6 to 4.4. No significant change in either property was observed for ratios higher than 4.4. In a cell adhesion assay under serum‐free conditions, the number of adherent platelets and smooth muscle cells decreased from 21 to 2% and from 78 to 20% of the initial seeding density, respectively, as the molar ratio increased from 0.6 to 7.8. Adherent smooth muscle cells did not spread on the hydrogels of the compositions tested. Adherent platelets did not show any filopodia. These results suggest that the hydrophilicity of P(PF‐co‐EG) hydrogels is one of the factors affecting cell adhesion, and that copolymer modification may be required for enhancing cell adhesion for an application involving the copolymers as in situ crosslinkable cell carriers. © 2002 Wiley Periodicals, Inc. J Biomed Mater Res 62: 558–566, 2002
Introduction of the green fluorescent protein gene into hematopoietic stem cells results in prolonged discrepancy of in vivo transduction levels between bone marrow progenitors and peripheral blood cells in nonhuman primates
Authors: Hanazono Yutaka , Terao Keiji , Shibata Hiroaki , Nagashima Takeyuki , Ageyama Naohide , Asano Takayuki , Ueda Yasuji , Kato Ikunoshin , Kume Akihiro , Hasegawa Mamoru , Ozawa Keiya 
Published: October 2002

AbstractBackgroundThe green fluorescent protein (GFP) has proven a useful marker in retroviral gene transfer studies targeting hematopoietic stem cells (HSCs) in mice. However, several investigators have reported very low in vivo peripheral blood marking levels in nonhuman primates after transplantation of HSCs transduced with the GFP gene. We retrovirally marked cynomolgus monkey HSCs with the GFP gene, and tracked in vivo marking levels within both bone marrow progenitor cells and mature peripheral blood cells following autologous transplantation after myeloablative conditioning.MethodsBone marrow cells were harvested from three cynomolgus macaques and enriched for the primitive fraction by CD34 selection. CD34+ cells were transduced with one of three retroviral vectors all expressing the GFP gene and were infused after myeloablative total body irradiation (500 cGy × 2). Following transplantation, proviral levels and fluorescence were monitored among clonogenic bone marrow progenitors and mature peripheral blood cells.ResultsAlthough 13–37% of transduced cells contained the GFP provirus and 11–13% fluoresced ex vivo, both provirus and fluorescence became almost undetectable in the peripheral blood within several months after transplantation regardless of the vectors used. However, on sampling of bone marrow at multiple time points, significant fractions (5–10%) of clonogenic progenitors contained the provirus and fluoresced ex vivo reflecting a significant discrepancy between GFP gene marking levels within bone marrow cells and their mature peripheral blood progeny. The discrepancy (at least one log) persisted for more than 1 year after transplantation. Since no cytotoxic T lymphocytes against GFP were detected in the animals, an immune response against GFP is an unlikely explanation for the low levels of transduced peripheral blood cells. Administration of granulocyte colony stimulating factor and stem cell factor resulted in mobilization of transduced bone marrow cells detectable as mature granulocyte progeny which expressed the GFP gene, suggesting that transduced progenitor cells in bone marrow could be mobilized into the peripheral blood and differentiated into granulocytes.ConclusionsLow levels of GFP‐transduced mature cells in the peripheral blood of nonhuman primates may reflect a block to differentiation associated with GFP; this block can be overcome in part by nonphysiological cytokine treatment ex vivo and in vivo. Copyright © 2002 John Wiley & Sons, Ltd.
Epidermal growth factor receptor targeting enhances adenoviral vector based suicide gene therapy of osteosarcoma
Authors: Witlox M. A. , van Beusechem V. W. , Grill J. , Haisma H. J. , Schaap G. , Bras J. , van Diest P. , de Gast A. , Curiel D. T. , Pinedo H. M. , Gerritsen W. R. , Wuisman P. I. J. M. 
Published: October 2002

AbstractBackgroundDespite improvements in the treatment of osteosarcoma (OS) there are still too many patients who cannot benefit from current treatment modalities. Therefore, new therapeutic approaches are warranted. Here we explore the efficacy of targeted adenoviral based suicide gene therapy.Methods and resultsImmunohistochemistry and FACS analysis detected low or absent expression levels of the primary adenovirus receptor CAR on human primary OS and human OS cell lines. These results predict a low infection efficiency and thus a reduced therapeutic effect. Targeting the adenoviruses to another receptor highly expressed on OS could overcome this limitation. We found epidermal growth factor receptor (EGFR) to be widely expressed on primary OS. Immunohistochemistry on primary tumor samples and FACS analysis on primary short‐term cultures and four OS cell lines showed that EGFR was consistently expressed. The recombinant bispecific single‐chain antibody 425‐s11 redirects adenoviral vectors towards the EGFR. Adenovirus transduction experiments in the presence or absence of 425‐s11 showed significantly enhanced gene transfer with the targeted adenoviral vector compared with the native vector (OS cell lines 2.5 to 7.2 times enhanced gene transfer and OS primary short term cultures 1.7 to 10 times enhanced gene transfer). On this basis, targeted suicide gene therapy experiments with AdCMVHSV‐TK in combination with ganciclovir were performed. These experiments demonstrated up to 3.5‐fold enhanced kill of OS cell lines and primary short‐term cultures by the EGFR targeted vector.ConclusionsSuicide gene therapy with adenovirus targeted towards EGFR may have favorable therapeutic characteristics for future gene therapy applications in OS. Copyright © 2002 John Wiley & Sons, Ltd.