bluuebunny/crossref_metadata_2025 huggingface dataset:
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

Background

Despite 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 results

Immunohistochemistry 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.

Conclusions

Suicide 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.
Kinetics and reactivity of substituted anilines with 2‐chloro‐5‐nitropyridine in dimethyl sulfoxide and dimethyl formamide
Authors: El‐Bardan Ali A. , El‐Subruiti Gehan M. , El‐Hegazy Fatma El‐Zahraa M. , Hamed Ezzat A.
Published: October 2002

The kinetics of the reaction of substituted anilines with 2‐chloro‐5‐nitropyridine were studied in dimethyl sulfonide (DMSO) and dimethyl formamide (DMF) at different amine concentrations and temperatures in the range 45–60°C. In both solvents the reaction was not a base‐catalyzed one. A plot of ΔH# versus ΔS# for the reaction in DMSO and DMF gave good straight lines with isokinetic temperatures 128°C and 105°C, respectively. Good linear relationships were obtained from the plots of log k1 against σ° values at all temperatures with negative ρ values (−1.63 to −1.28 in DMSO) and (−1.26 to −0.90 in DMF). © 2002 Wiley Periodicals, Inc. Int J Chem Kinet 34: 645–650, 2002
Effects of Er:YAG laser irradiation on human dentin: Polarizing microscopic, light microscopic and microradiographic observations, and FT‐IR analysis
Authors: Ishizaka Yaeko , Eguro Toru , Maeda Toru , Tanaka Hisayoshi
Published: October 2002

Background and Objectives

The effects of Er:YAG laser irradiation on dentin have not been sufficiently investigated. The purpose of this study was to investigate the effects of Er:YAG laser irradiation on dentin.

Study Design/Materials and Methods

After cavities were prepared using Er:YAG laser irradiation or rotary cutting instruments, histological observations of cavity‐floor dentin utilizing polarizing microscopy, microradiography and light microscopy, and analysis of composition of cavity‐floor dentin using Fourier‐transformed (FT‐IR) spectrometry were conducted.

Results

In the laser‐treated side, a deeply stained basophilic layer was observed. The number of odontoblastic processes present was obviously less in the laser‐treated side than in the bur‐treated side. FT‐IR analysis revealed that compared to the bur‐treated side, a broad background peak at around 1,600 cm−1 was present.

Conclusions

Er:YAG laser irradiation might have denatured the organic materials of dentin. Lasers Surg. Med. 31:171–176, 2002. © 2002 Wiley‐Liss, Inc.
Photoeradication of Helicobacter pylori using 5‐aminolevulinic acid: Preliminary human studies
Authors: Wilder‐Smith Clive H. , Wilder‐Smith Petra , Grosjean Pierre , van den Bergh Hubert , Woodtli Alain , Monnier Philippe , Dorta Gian , Meister Friedrich , Wagnières Georges
Published: October 2002

Background and Objectives

Helicobacter pylori (HP) is an endemic pathogenic bacterium causing gastritits and gastroduodenal ulceration in humans and is linked to the development of gastric malignancies. These first human in vivo studies investigated the photoeradication of HP using laser and white light.

Study Design/Materials and Methods

In 13 HP‐positive volunteers, a zone of gastric antrum was irradiated with laser (410 nm, 50 J/cm2) or endoscopic white light (10 J/cm2) 45 minutes after oral 5‐aminolevulinic acid (5‐ALA) 20 mg/kg. HP‐eradication was assessed by biopsy urease test and HP‐culture from irradiated and control zones 5 minutes, 4 and 48 hours post‐irradiation.

Results

A maximum eradication effect was achieved at 4 hours post‐irradiation when 85% of biopsies in the monochromatic and 66% in the white light exposed zones, and 58 and 33% in the respective control zones were HP‐negative.

Conclusions

HP numbers were greatly reduced following exposure to 5‐ALA and either laser or white light in vivo. Photoeradication appears feasible, but further light dosimetry and the development of convenient application methods is required. Lasers Surg. Med. 31:18–22, 2002. © 2002 Wiley‐Liss, Inc.
Cryogen spray cooling efficiency: Improvement of port wine stain laser therapy through multiple‐intermittent cryogen spurts and laser pulses
Authors: Aguilar Guillermo , Díaz Sergio H. , Lavernia Enrique J. , Nelson J. Stuart
Published: October 2002

Background and Objectives

Cryogen spray cooling (CSC) is used to minimize the risk of epidermal damage during laser treatment of port wine stain (PWS) birthmarks. Unfortunately, CSC may not provide the necessary protection for patients with high concentrations of epidermal melanin. The objectives of this study are to: (1) provide a definition of cooling efficiency (η) based on the amount of heat removed per unit area of skin for a given cooling time; (2) using this definition, establish the η of previously reported spray nozzles; (3) identify the maximum benefit expected in PWS laser therapy based solely on improvement of η; and (4) study the feasibility of using multiple‐intermittent cryogen spurts and laser pulses to improve PWS laser therapy.

Study Design/Materials and Methods

A theoretical definition to quantify η is introduced. Subsequently, finite difference heat diffusion and Monte Carlo light distribution models are used to study the spatial and temporal temperature distributions in PWS skin considering: (1) the current approach to PWS laser therapy consisting of a single cryogen spurt followed by a single pulsed dye laser exposure (SCS‐SLP approach); and (2) multiple cryogen spurts and laser pulses (MCS‐MLP approach). At the same time, an Arrhenius‐type kinetic model is used to compute the epidermal and PWS thermal damages (ΩE and ΩPWS, respectively) for a high epidermal melanin concentration (20%), corresponding to skin types V–VI.

Results

The η corresponding to a wide range of heat transfer coefficients (h) is quantified. For reported CSC nozzle devices η varies from 40 to 98%. Using the SCS‐SLP approach, it is shown that even η = 100% cannot prevent excessive ΩE for a skin types V–VI. In contrast, the MCS‐MLP approach provides adequate epidermal protection while permitting PWS photocoagulation for the same skin types.

Conclusions

The new proposed definition allows to compute the cooling efficiency of CSC nozzle devices. Computer models have been developed and used to show that the SCS‐SLP approach will not provide adequate epidermal protection for darker skin patients (skin types V–VI), even for η = 100%. In contrast, the MCS‐MLP approach may be a viable solution to improve PWS laser therapy for darker skin patients. Lasers Surg. Med. 31:27–35, 2002. © 2002 Wiley‐Liss, Inc.
Direct experience and the strength of the personal norm–behavior relationship
Authors: Thøgersen John
Published: October 2002

This study investigates whether the behavioral influence of personal norms with regard to repeated pro‐social behavior depends on direct experience of this behavior. Based on previous norm and attitude research, it is hypothesized that (a) direct experience strengthens the influence of personal norms on behavior, and (b) direct experience is a stronger moderator in this case than in the attitude–behavior case. The case in question is the purchase of organic red wine. It is found that the outcome of consumers' choice between organic and nonorganic wine depends on their personal (moral) norms, after controlling for attitudes and subjective social norms. However, the influence of personal norms, though not of attitude, depends on whether the consumer has direct experience of buying organic red wine. Hence, both hypotheses are confirmed. © 2002 Wiley Periodicals, Inc.
Hepatoblastoma: Assessment of criteria for histologic classification
Authors: Rowland Jon M.
Published: October 2002

Background

Comparison of outcomes in different clinicopathologic studies of hepatoblastoma requires reproducible histologic classification. This review examines the diagnostic criteria employed by different pathologists for the classification of subtypes of hepatoblastoma and identifies specific problem areas.

Procedure

A selected review of published literature is provided.

Results

Published studies demonstrate that uniform criteria have not been applied in the classification of hepatoblastoma. These discrepancies hinder attempts to compare outcome data from different studies. Sampling error and potential treatment effects further complicate analysis of the published literature on the relationship between morphologic classification and outcome.

Conclusions

Standardized criteria are essential to allow reproducible histologic classification of hepatoblastoma. There is significant variation in diagnostic criteria used to define the major subtypes of hepatoblastoma in published studies. Additional potential problems are identified in sampling methods and treatment effects. Med Pediatr Oncol 2002;39:478–483. © 2002 Wiley‐Liss, Inc.
Chemotherapy for suspected hepatoblastoma without efforts at surgical resection is a bad practice
Authors: Finegold Milton J.
Published: October 2002

Background

US and European practices differ with respect to treating hepatoblastoma (HB). Should chemotherapy be given prior to resection in all cases, and even without biopsy confirmation (SIOPEL)?

Procedure and Results

US data indicate that 40% of HBs are primarily resectable with no operative mortality and that those with pure fetal histology and low mitotic rate do not require toxic chemotherapy. They also suggest that those with a significant fraction of small undifferentiated cells do not respond to otherwise effective chemotherapy. Both US and European studies report a significant error rate in the clinical and imaging diagnosis of HB.

Conclusions

Although only 6.5% of confirmed HBs fall into categories that would be managed differently by US standards, there is no justification for denying those patients a more appropriate treatment nor should the 6–10% of cases that are misdiagnosed as HB be treated incorrectly. Med Pediatr Oncol 2002;39:484–486. © 2002 Wiley‐Liss, Inc.
Data from frequency‐volume charts versus maximum free flow rate, residual volume, and voiding cystometric estimated urethral obstruction grade and detrusor contractility grade in men with lower urinary tract symptoms suggestive of benign prostatic hyperplasia
Authors: van Venrooij Ger E.P.M. , Eckhardt Mardy D. , Boon Tom A.
Published: October 2002

Aims

To examine associations of data from frequency‐volume charts with maximum free flow rate, residual volume, and voiding cystometric estimated urethral obstruction grade and detrusor contractility in men with lower urinary tract symptoms suggestive of benign prostatic hyperplasia (BPH).

Methods

The 160 men included in the study met the criteria of the International Scientific Committee on BPH, i.e., they voided more than 150 mL during uroflowmetry, their residual volume and prostate size were estimated, and they completed frequency‐volume charts correctly. From the frequency‐volume charts, voiding habits and fluid intake were evaluated. Pressure‐flow studies were performed as well.

Results

Increasing residual volume was related to a decrease of maximum voided volume and to a decrease of maximum free flow rate. Cystometric capacity was little affected by residual volume. Low contractility did not result in high residual volume. A marked decrease in voided volumes with increasing obstruction grade was observed, due to a decrease of cystometric capacity and an increase of residual volume. Detrusor contractility was little associated with voided volumes. A higher voiding frequency was related to a higher fluid intake. However, increased standardized frequency (number of voidings per 1,000 mL) was associated with a substantial reduction of fluid intake.

Conclusions

Infravesical obstruction is the most important factor influencing voided volumes, cystometric capacity, and residual urine volume. Frequency of voiding was not influenced significantly because patients with small voided volumes minimized their fluid intake. Neurourol. Urodynam. 21:450–456, 2002. © Wiley‐Liss, Inc.
Comparison of the experience with acute and chronic electrically stimulated detrusor myoplasty
Authors: Van Savage John G. , Perez‐Abadia Gustavo , Palanca Lucio G. , Bardoel Janou W. , Harralson Thomas , Amin Mohammad , Palacio Martin , Tobin Gordon , Maldonado Claudio , Barker John H.
Published: October 2002

Aims

To evaluate the acute and chronic urodynamic effects of electrically stimulated detrusor myoplasty in dogs.

Methods

Eight female mongrel dogs were studied acutely and six dogs chronically (0 to 12 weeks postoperatively). Bladders were wrapped with the rectus abdominis muscle, keeping an intact blood supply and at least two intercostal nerves of the flap preserved. Bladders were electrically stimulated with bipolar electrodes inserted into the muscle. Urodynamics and post void residual were measured post operatively in the acute studies and every 2 weeks for 3 months in chronic studies.

Results

Acutely, the increase in intravesical pressure was 45±7 cm H2O, which resulted in a postvoid residual of 26±3%. In the chronic study, increases of intravesical pressure sufficient to empty the bladder during myoplasty electrical stimulation were not sustained, although detrusor compliance and flap viability were preserved.

Conclusions

The electrically stimulated detrusor myoplasty worked well acutely to increase vesical pressure sufficient to empty the bladder, but the chronically stimulated myoplasty did not maintain efficient bladder emptying primarily due to electrode problems. Further studies with improved electrode material and placement are required before clinical application of the electrically stimulated detrusor myoplasty can be assessed. Neurourol. Urodynam. 21:516–521, 2002. © Wiley‐Liss, Inc.
Early discharge following abdominal aortic aneurysm repair: Impact on patients and caregivers
Authors: Jones Mildred A. , Hoffman Leslie A. , Makaroun Michel S. , Zullo Thomas G. , Chelluri Lakshmipathi
Published: October 2002

Although early discharge is common place, little is known about its impact after abdominal aortic aneurysm (AAA) surgery. We sought to prospectively describe patient outcomes and caregiving experience after early discharge following elective AAA repair using a standard or endovascular grafting system (EGS) procedure. Fifty‐one patients (Standard, n=25; EGS, n=26) completed questionnaires on symptoms and health‐related quality of life (HRQoL) while hospitalized and 1, 4, and 8 weeks after discharge. Data were also obtained from caregivers. HRQoL decreased at Week 1 in both groups but returned to near baseline by Week 8. Standard AAA patients experienced more symptoms and activity limitations, but these were concentrated in Week 1. Most caregivers were positive about caregiving and required no additional resources. Findings suggest that most patients who undergo early discharge following elective AAA surgery experience few problems. Those problems that occur concentrate in the week following discharge, suggesting the need for closer monitoring at this time. © 2002 Wiley Periodicals, Inc. Res Nurs Health 25:345–356, 2002
Association between fetal nuchal translucency thickness in first trimester and subsequent gestational hypertension and preeclampsia
Authors: Tsai Ming‐Song , Lee Fa‐Kung , Cheng Chih‐Chien , Hwa Kuo‐Yuan , Cheong Mei‐Leng , She Bo‐Quing
Published: October 2002

Increased fetal nuchal translucency (NT) in the first trimester is associated with adverse pregnancy outcomes. Whether the increased NT is also associated with an increased frequency of pregnancy‐associated hypertension (PAH) is not known. Seven hundred and seventy‐nine pregnant women who received NT‐based Down syndrome screening and delivered their babies at our hospital by September 2000 were enrolled into this study. Among these women, there are 46 cases of preeclampsia, 68 cases of gestational hypertension (GH); 665 women without any adverse pregnancy outcomes served as controls. Correlation analysis demonstrated that NT MoM (multiples of median) level had a positive association with maternal diastolic blood pressure at the time of admission for delivery (r = 0.104; p < 0.01). The severity of PAH was concordant with the stepwise increase of mean NT MoM level, which was 0.88 in control, 1.07 in gestational hypertension, and 1.13 in preeclampsia (p < 0.001). Using the 95th (1.52 MoM) and 90th (1.31 MoM) percentiles of NT thickness as cut‐offs, the sensitivities and odds ratios of the women at risk for developing GH after 20 weeks of gestation were 8.8%, 19.1% and 1.98, 2.15 respectively, while for preeclampsia were 10.9%, 28.3% and 2.49, 3.58 respectively. It is concluded that the pathological changes in the placenta responsible for the development of PAH may also influence the physiological decrease of NT thickness in late first trimester. However, the sensitivity of fetal NT measurement in first trimester is not sufficient as a single marker for predicting the pregnant women at risk for subsequent PAH. Copyright © 2002 John Wiley & Sons, Ltd.
Factors affecting the decision regarding amniocentesis in women at genetic risk because of age 35 years or older
Authors: Vergani Patrizia , Locatelli Anna , Biffi Anna , Ciriello Elena , Zagarella Andrea , Pezzullo John C. , Ghidini Alessandro
Published: October 2002

Objective

To evaluate the effects of anamnestic factors and sonographic findings on the patient's decision regarding amniocentesis in a cohort of women at genetic risk because of advanced age.

Methods

All women 35 years of age or older registered for prenatal care between January 1990 and December 1998 were asked about their attitude towards genetic amniocentesis during the course of individual genetic counseling and once again after ultrasound examination inclusive of markers of aneuploidies (nuchal fold thickness greater than 6 mm, renal pyelectasis, choroid plexus cysts, and hyperechogenic bowel). Their attitudes towards genetic amniocentesis before and after ultrasound examination were compared using chi‐square, Fisher's exact test, Mann–Whitney U‐test, and logistic regression analysis, with a two‐tailed p < 0.05 or an odds ratio (OR) with 95% confidence interval (CI) not inclusive of the unity considered significant.

Results

Among the 1486 women in the cohort, 1368 (97%) expressed an opinion towards genetic testing at the time of counseling: 501 (37%) were in favor and 867 (63%) were against having the procedure. After ultrasonographic examination, 33% (446/1368) of women opted for amniocentesis, 36% (146/402) after abnormal findings and 31% (300/966) after normal ultrasound findings. Significantly more women with abnormal than normal ultrasound findings opted for diagnostic testing in both groups. Overall, only 8% (115/1368) of women changed their attitude towards diagnostic testing after ultrasonographic examination. Normal sonographic findings were three times more likely to change the attitude of women initially interested in amniocentesis than abnormal sonographic findings did in women a priori not interested in the procedure (20% versus 7%, p < 0.001, OR = 3.2, 95% CI 1.8; 5.8).

Conclusions

In a cohort of women at genetic risk because of advanced age, the key determinant of the choice regarding genetic amniocentesis is the a priori opinion of the woman towards the procedure, which was expressed by 93% of women. Ultrasonography plays a secondary role in changing or confirming women's attitude towards invasive diagnostic testing. Normal sonographic findings affect women's decisions more powerfully than abnormal sonographic findings, suggesting that ultrasonography has an important reassuring function for the woman. Copyright © 2002 John Wiley & Sons, Ltd.
Aromatic polyamides derived from unsymmetrical diamines containing the phthalazinone moiety
Authors: Cheng Lin , Jian Xi Gao , Mao Shi Zhen
Published: October 2002

Two unsymmetrical and kink non‐coplanar heterocyclic diamines, 1,2‐dihydro‐2‐(4‐aminophenyl)‐4‐[4‐(4‐aminophenoxy)phenyl](2H)phthalazin‐1‐one and 1,2‐dihydro‐2‐(4‐aminophenyl)‐4‐[4‐(4‐aminophenoxy)‐3,5‐dimethylphenyl](2H) phthalazin‐1‐one, were successfully synthesized by readily available heterocyclic bisphenol‐like monomers through two steps in high yields. A series of novel poly(arylene ether amides)s containing the phthalazinone moiety with inherent viscosities of 1.16–1.67 dL/g were prepared by the direct polymerization of novel diamines and aromatic dicarboxylic acids using triphenyl phosphite and pyridine as condensing agents. The polymers were readily soluble in a variety of solvents such as N,N‐dimethylformamide, N,N‐dimethylacctamide, dimethyl sulfoxide, N‐methyl‐2‐pyrrolidone, and even in pyridine, chloroform and m‐cresol. The glass‐transition temperatures were in the range of 291–329 °C, and the temperatures for 5% weight loss in nitrogen were above 490 °C. © 2002 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 40: 3489–3496, 2002
Synthesis of lipo‐glycopolymer amphiphiles by nitroxide‐mediated living free‐radical polymerization
Authors: Götz Heide , Harth Eva , Schiller Stefan M. , Frank Curtis W. , Knoll Wolfgang , Hawker Craig J.
Published: October 2002

The nitroxide‐mediated living free‐radical polymerization of 1,2,5,6‐di(isopropylidene)‐D‐glucose‐2‐propenoate was achieved in dimethylformamide at 105 °C with an α‐hydrido alkoxyamine initiator functionalized with a lipophilicN,N‐di(octadecyl)amine group. The kinetics of the polymerization were investigated, and the mechanism was shown to be a living process allowing, after hydrolysis, controlled molecular weight, low‐polydispersity lipo‐glycopolymers to be prepared. The amphiphilic character of the macromolecule could be altered by either the exchange of the alkoxyamine at the chain end with hydrogen or the preparation of copolymers with lipophilic monomers such asN,N‐di(octadecyl)acrylamide. The surface and membrane‐forming properties of these novel lipopolymers demonstrate their amphiphilic character. © 2002 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 40: 3379–3391, 2002
Synthesis, structural analysis, and visualization of poly(2‐ethynyl‐9‐substituted carbazole)s and poly(3‐ethynyl‐9‐substituted carbazole)s containing chiral and achiral minidendritic substituents
Authors: Percec Virgil , Obata Makoto , Rudick Jonathan G. , De Binod B. , Glodde Martin , Bera Tushar K. , Magonov Sergei N. , Balagurusamy V. S. K. , Heiney Paul A.
Published: October 2002

The synthesis of 2‐ethynyl‐9‐substituted carbazole and 3‐ethynyl‐9‐substituted carbazole monomers containing first‐generation chiral and achiral dendritic (i.e., minidendritic) substituents, 2‐ethynyl‐9‐[3,4,5‐tris(dodecan‐1‐yloxy)benzyl]carbazole (2ECz), 3‐ethynyl‐9‐[3,4,5‐tris(dodecan‐1‐yloxy)benzyl]carbazole (3ECz), 2‐ethynyl‐9‐{3,4,5‐tris[(S)‐2‐methylbutan‐1‐yloxy]benzyl}carbazole (2ECz*), and 3‐ethynyl‐9‐{3,4,5‐tris[(S)‐2‐methylbutan‐1‐yloxy]benzyl}carbazole (3ECz*), is presented. All monomers were polymerized and copolymerized by stereospecific polymerization to produce cis‐transoidal soluble stereoisomers. A structural analysis of poly(2ECz), poly(2ECz*), poly(3ECz), poly(3ECz*), poly(2ECz*‐co‐2ECz), and poly(3ECz*‐co‐3ECz) by a combination of techniques, including 1H NMR, ultraviolet–visible, and circular dichroism spectroscopy, thermal optical polarized microscopy, and X‐ray diffraction experiments, demonstrated that these polymers had a helical conformation that produced cylindrical macromolecules exhibiting chiral and achiral nematic phases. Individual chains of these cylindrical macromolecules were visualized by atomic force microscopy. © 2002 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 40: 3509–3533, 2002
Impact of incorporating the 2C5 crystal structure into comparative models of cytochrome P450 2D6
Authors: Kirton Stewart B. , Kemp Carol A. , Tomkinson Nicholas P. , St.‐Gallay Steven , Sutcliffe Michael J.
Published: October 2002

Cytochrome P450 2D6 (CYP2D6) metabolizes approximately one third of the drugs in current clinical use. To gain insight into its structure and function, we have produced four different sets of comparative models of 2D6: one based on the structures of P450s from four different microorganisms (P450 terp, P450 eryF, P450 cam, and P450 BM3), another on the only mammalian P450 (2C5) structure available, and the other two based on alternative amino acid sequence alignments of 2D6 with all five of these structures. Principal component analysis suggests that inclusion of the 2C5 crystal structure has a profound effect on the modeling process, altering the general topology of the active site, and that the models produced differ significantly from all of the templates. The four models of 2D6 were also used in conjunction with molecular docking to produce complexes with the substrates codeine and 1‐methyl‐4‐phenyl‐1,2,3,6‐tetrahydropyridine (MPTP); this identified Glu 216 [in the F‐helix; substrate recognition site (SRS) 2] as a key determinant in the binding of the basic moiety of the substrate. Our studies suggest that both Asp 301 and Glu 216 are required for metabolism of basic substrates. Furthermore, they suggest that Asp 301 (I‐helix, SRS‐4), a residue thought from mutagenesis studies to bind directly to the basic moiety of substrates, may play a key role in positioning the B′‐C loop (SRS‐1) and that the loss of activity on mutating Asp 301 may therefore be the result of an indirect effect (movement of the B′‐C loop) on replacing this residue. Proteins 2002;49:216–231. © 2002 Wiley‐Liss, Inc.
Generic serial and parallel on‐line direct‐injection using turbulent flow liquid chromatography/tandem mass spectrometry
Authors: Grant Russell P. , Cameron Cheryl , Mackenzie‐McMurter Shelley
Published: October 2002

The development of turbulent flow chromatography (TFC) has enabled considerable growth in the utility of on‐line direct‐injection technologies. TFC has now become established in a large number of varied analytical environments, particularly drug discovery/pharmacokinetics, metabolite profiling, combinatorial library purification, pre‐clinical and clinical GLP applications. The utility of turbulent flow technology for in‐house pre‐clinical and clinical quantitative applications has necessitated extensive valve‐cleaning procedures, and consequently lengthy cycle‐times, to effectively remove the system carry‐over. In‐house requirements for assay validation require carry‐over less than 20% of the lowest level of quantification (LLOQ), corresponding to 0.02% carry‐over for a linear calibration range incorporating 3 orders. A generic turbulent flow chromatography protocol has been developed for drug discovery that incorporates polymeric turbulent flow extraction (cyclone) with C18‐based reverse‐phase chromatography. Further, multiple wash steps are incorporated within the methodology to meet in‐house requirements for carry‐over. Selection of novel switching‐valve materials based on polyarylethyl ketone (PAEK) and Hastelloy/Valcon E autosampler injection hardware has enabled us to significantly impact the cycle‐time required to reduce carry‐over. Consequently, optimal usage of switching valves has enabled parallel operation for a generic on‐line direct‐injection methodology to successfully reduce the total cycle‐time. Overall reductions from 4 min per sample to 90 s per sample are shown with comparable data quality using a proprietary target molecule from 0.1–100 ng/mL. This paper describes the hardware configuration and methodologies utilized to perform generic serial and parallel on‐line direct‐injection using a Turboflow HTLC 2300 system. Copyright © 2002 John Wiley & Sons, Ltd.
Direct determination of alkyl phosphates in human urine by liquid chromatography/electrospray tandem mass spectrometry
Authors: Hernández Félix , Sancho Juan V. , Pozo Oscar J.
Published: October 2002

A novel and rapid procedure based on liquid chromatography/tandem mass spectrometry (LC/MS/MS) for the determination of dialkyl phosphates (metabolites of organophosphorus pesticides) in human urine has been developed. After addition of 40 mM tetrabutylammonium acetate, 10 µL of urine sample were directly injected into the LC/MS/MS system. The method was validated yielding calibration curves with correlation coefficients greater than 0.997 and repeatability coefficient of variation (CV) lower than 9%. The accuracy and precision were evaluated by direct injection of spiked samples at 10 and 100 µg/L obtaining recoveries between 78 and 119% with coefficients of variation below 12%. Limits of detection of 1 µg/L for diethyl phosphate (DEP), diethylthiophosphate (DETP) and diethyldithiophosphate (DEDTP) and 2 µg/L for dimethyldithiophosphate (DMDTP) were achieved, all the analytes being detected in negative ion mode. The fragmentation pathway of dialkyl phosphates allowed us the use of an additional transition for confirmation in order to improve their identification in real‐world samples. The applicability of the LC/MS/MS method was demonstrated by applying it to the analysis of urine samples of farmers exposed to the organophosphorus pesticide chlorpyrifos. Good correlation between application of the product in the field (citrus orchards), concentration levels of dialkyl phosphates and levels of the chlorpyrifos‐specific metabolite (1,3,5‐trichloro‐2‐pyridinol) was obtained. Copyright © 2002 John Wiley & Sons, Ltd.
Alphavirus vectors and vaccination
Authors: Rayner Jonathan O. , Dryga Sergey A. , Kamrud Kurt I.
Published: October 2002

Alphaviruses are positive‐stranded RNA viruses that have a broad host range and therefore are capable of replicating in many vertebrate and invertebrate cells. The single‐stranded alphavirus genome is divided into two ORFs. The first ORF encodes the nonstructural proteins that are translated upon entry of the virus into the cytoplasm and are responsible for transcription and replication of viral RNA. The second ORF is under the control of a subgenomic promoter and normally encodes the structural proteins, which are responsible for encapsidation of viral RNA and final assembly into enveloped particles. Expression vectors have been engineered from at least three alphaviruses in which the structural protein gene region has been replaced by heterologous genes and have been shown to express high levels of the heterologous protein in cultured cells. These RNA vectors, known as replicons, are capable of replicating on their own but are not packaged into virus‐like particles unless the structural proteins are provided in trans. Thus, replicons are single cycle vectors incapable of spreading from infected to noninfected cells. Because of these features, alphavirus replicon vectors are being developed as a platform vaccine technology for numerous viral, bacterial, protozoan and tumour antigens where they have been shown to be efficient inducers of both humoral and T cell responses. In addition, as the alphavirus structural proteins are not expressed in vaccine recipients, antivector immune responses are generally minimal, allowing for multiple effective immunisations of the same individual. Copyright © 2002 John Wiley & Sons, Ltd.
An introduction to the use of neural networks in control systems
Authors: Hagan Martin T. , Demuth Howard B. , Jesús Orlando De
Published: October 2002

The purpose of this paper is to provide a quick overview of neural networks and to explain how they can be used in control systems. We introduce the multilayer perceptron neural network and describe how it can be used for function approximation. The backpropagation algorithm (including its variations) is the principal procedure for training multilayer perceptrons; it is briefly described here. Care must be taken, when training perceptron networks, to ensure that they do not overfit the training data and then fail to generalize well in new situations. Several techniques for improving generalization are discussed. The paper also presents three control architectures: model reference adaptive control, model predictive control, and feedback linearization control. These controllers demonstrate the variety of ways in which multilayer perceptron neural networks can be used as basic building blocks. We demonstrate the practical implementation of these controllers on three applications: a continuous stirred tank reactor, a robot arm, and a magnetic levitation system. Copyright © 2002 John Wiley & Sons, Ltd.
A review of hydroecological results of the Northern River Basins Study, Canada. Part 2. Peace–Athabasca Delta
Authors: Prowse T. D. , Conly F. M.
Published: October 2002

The Peace–Athabasca Delta (PAD) in northern Canada is one of the world's largest freshwater deltas. Concern developed over the ecological health of this system in the early 1970s following regulation of its main headwater tributary, the Peace River. Continued drying of the delta into the 1990s resulted in the initiation of two major science programs, the Northern River Basins Study and the Peace–Athabasca Delta Technical Studies. Recognizing the importance of water to restoring and maintaining biological productivity and diversity of the PAD, a series of studies was initiated to explain the reasons for the protracted drying and to design methods to restore flooding. These studies demonstrated that open‐water floods from the Peace River were unlikely to flood the ecologically sensitive perched basins within the PAD. Moreover they discovered that most large‐scale overbank flooding resulted from ice‐jams formed during spring break‐up. Increases in freeze‐up ice levels due to enhanced winter flows from the reservoir and a decrease in spring snowmelt runoff from downstream tributaries were suggested as being responsible for a decline in the frequency and severity of ice‐jam floods. Based on results from numerical modelling studies of ice‐jams, a flow augmentation strategy was designed to aid the formation of ice‐jams near the PAD. Results of a test trial based on this strategy are presented. An update is also provided about ecological studies conducted since the delta was recharged by floodwaters in 1996. Copyright © 2002 Environment Canada. Published by John Wiley & Sons, Ltd.
Classification of adsorbed protein static ToF‐SIMS spectra by principal component analysis and neural networks
Authors: Sanni O. D. , Wagner M. S. , Briggs D. , Castner D. G. , Vickerman J. C.
Published: October 2002

Analysis of the static time‐of‐flight secondary ion mass spectrometry (ToF‐SIMS) spectra of adsorbed protein films is reported using principal component analysis (PCA) and a novel artificial neural network (ANN) approach,NeuroSpectraNet, to classify chemically the spectra of the protein films. The ease of application and the efficiency with which each approach classified positive ion spectra from adsorbed films of 13 different proteins is reported and assessed. The ToF‐SIMS spectra of adsorbed protein films are especially difficult to analyze owing to the absence of unique peaks in the spectra of different proteins. Although PCA was able to differentiate successfully ToF‐SIMS spectra of adsorbed protein films using the ions generated from the fragmentation of the amino acids, differentiation of the spectra using the entire spectrum was unsuccessful. Outliers in several of the protein groups make classification of unknown spectra difficult, despite the use of only amino‐acid‐specific ions. However,NeuroSpectraNetsuccessfully classified the spectra from 11 of the protein films using the whole positive ion spectra after a vector analysis enhancement had been incorporated into the neural network. Full classification of all 13 proteins was achieved by using the combined positive and negative ion spectra. However, as with PCA, ANN classification was enhanced when the input patterns only contained amino‐acid‐specific ions. The complex and multivariate nature of static SIMS spectra is a domain well suited to the application of neural networks for pattern recognition and classification. Copyright © 2002 John Wiley & Sons, Ltd.
Intensive short courses in biostatistics for fellows and physicians
Authors: Ambrosius Walter T. , Manatunga Amita K.
Published: October 2002

At both of our universities we teach (with colleagues) introductory courses in statistics for fellows and physicians. We do not expect that those taking these courses will be able to do their own statistical work, but rather the intention is for them to ‘learn the language’ and to facilitate future collaboration. Basic principles of study design are introduced in the courses, as well as some of the most common statistical procedures. We will discuss the factors (what works and what does not) that may contribute to a successful course, a comparison to other courses, and our self‐evaluation strategy. Finally, we will cover the financial arrangements that we have made when teaching these courses. Copyright © 2002 John Wiley & Sons, Ltd.
Virtual‐machine‐based heterogeneous checkpointing
Authors: Agbaria Adnan , Friedman Roy
Published: October 2002

Checkpointingan application is the act of saving the application's state during its execution on stable storage, so that if the application fails it can berestartedfrom the last saved state, thereby avoiding loss of the work that was already done. Aheterogeneous checkpoint/restartmechanism allows one to restart an application on a possibly different hardware architecture and/or operating system than those in which the application was saved. This paper explores how to construct such a mechanism at the virtual machine level. That is, rather than dumping the entire state of the application process, the mechanism reported here dumps the state of the application as maintained by a virtual machine. During restart, the saved state is loaded into a new copy of the virtual machine, which continues running from there. The heterogeneous checkpoint/restart mechanism reported here was developed for the OCaml variant of ML. The paper reports on the main issues encountered in building such a mechanism and the design choices made, presents performance evaluations, and discusses some lessons and ideas for extending the work to native code OCaml and Java. Copyright © 2002 John Wiley & Sons, Ltd.
Influence of aging and social isolation on changes in brain monoamine turnover and biosynthesis of rats elicited by novelty stress
Authors: Miura Hideki , Qiao Hong , Ohta Tatsuro
Published: October 2002

Aging is a risk factor of human depression. Middle‐aged or older men are vulnerable to adverse life events and an absence of social contact and easily become depressed. In the present study, we investigated the influence of aging on responses to life events in socially isolated conditions. We applied isolation‐rearing (4 W) to two age groups, older (18 M) and younger (11 W), of male F344 rats that had been reared in a group and then examined responses to novelty stress (20 min). Changes in brain monoamines and their metabolites such as dopamine (DA), serotonin (5‐HT), dihydroxyphenylacetic acid (DOPAC), homovanilic acid (HVA), and 5‐hydroxyindoleacetic acid (5‐HIAA) were measured in six regions: the prefrontal cortex, nucleus accumbens, hippocampus, amygdala, midbrain, and raphe nuclei. MANOVA was carried out for rearing condition, age, and novelty stress. Isolation significantly changed monoamines and their metabolites, except in amygdala and raphe nuclei. Aging significantly altered them in all regions, although novelty stress did not. In the amygdala and midbrain, isolation significantly changed monoamine biosynthesis, with monoamine turnover remaining unchanged. In the prefrontal cortex and nucleus accumbens, aging significantly altered turnover, while biosynthesis remained unchanged. Novelty stress significantly varied only the turnover in the prefrontal cortex. The interaction between isolation and aging indicated that aging influences changes in turnover and biosynthesis elicited by isolation primarily at the center of the mesolymbic DA system, the midbrain, and in raphe nuclei of the 5‐HT system. In peripheral regions of the mesolymbic system, aging primarily affects changes in turnover induced by isolation. Synapse 46:116–124, 2002. © 2002 Wiley‐Liss, Inc.
Brain DA D2 receptors predict reinforcing effects of stimulants in humans: Replication study
Authors: Volkow Nora D. , Wang Gene‐Jack , Fowler Joanna S. , Thanos Pether , Logan Jean , Gatley Samuel J. , Gifford Andrew , Ding Yu‐Shin , Wong Chris , Pappas Naomi
Published: October 2002

We had shown that striatal DA D2 receptors levels predicted the reinforcing responses to the psychostimulant drug methylphenidate in nondrug‐abusing subjects. Here, we assessed the replicability of this finding. We measured D2 receptors with PET and [11C]raclopride (twice to determine stability) in seven nondrug‐abusing subjects to assess if they predicted the self‐reports of “drug‐liking” to intravenous methylphenidate (0.5 mg/kg). DA D2 measures were significantly correlated with “drug‐liking” in both evaluations (r = 0.82 and r = 0.78); subjects with the lowest levels reported the higher ratings of “drug‐liking” and vice versa. These results replicate our previous findings and provide further evidence that striatal DA D2 receptors modulate reinforcing responses to stimulants in humans and may underlie predisposition for drug self‐administration. Synapse 46:79–82, 2002. © 2002 Wiley‐Liss, Inc.
Chemotactic response of unicellular tetrahymena to a leukocyte attractant peptide and its repellent derivate: evolutionary conclusions.
Authors: Kõhidai László , Kovács Péter , Csaba György
Published: October 2002

Chemotactic properties of the leukocyte chemoattractant N‐formyl‐Norleucine‐Leucine‐Phenylalanine (NLP) and its antagonist N‐t‐BOC‐Norleucine‐Leucine‐Phenylalanine (BOC‐NLP) were investigated in unicellular Tetrahymena pyriformis cells. NLP express its attractant character in a two‐peak profile of concentration course (maximum at 10−8‐10−7 M and 10−11 M) while BOC‐NLP has a constant repellent character (maximum at 10−12 M). The observed homology of action concurs with our theory about the wide evolutionary background of signal molecules and receptors.
New Species of Lichenized and Non-Lichenized Ascomycetes from a Rainforest Canopy in Southern Venezuela
Authors: Komposch Harald , Aptroot André , Hafellner Josef
Published: October 2002

Four species of corticolous lichenized and non-lichenized ascomycetes are described from a tropical lowland rainforest in southern Venezuela: Mycomicrothelia xanthonica Komposch, Aptroot & Hafellner along with the closely related M. macrocarpa Komposch, Aptroot & Hafellner (Arthopyreniaceae), Pseudopyrenula cryptotheca Komposch, Aptroot & Hafellner (Trypetheliaceae), and Ancistrosporella psoromica Komposch, Aptroot & Hafellner (Opegraphaceae). Descriptions and illustrations are presented and the relationships of the taxa discussed. In addition, the following new combination is proposed: Ancistrosporella curvata (Aptroot) Komposch (Opegrapha curvata Aptroot). Ancistroporella G.Thor is regarded as typographical error and corrected to Ancistrosporella.
Nutritive Value of Terricolous Lichens for Reindeer in Winter
Authors: Storeheier Pål Vegar , Mathiesen Svein D. , Tyler Nicholas J. C. , Olsen Monica A.
Published: October 2002

In contrast to virtually all other species of ruminants, reindeer (Rangifer arandus) eat substantial amounts of lichens in winter. Several different species of lichens are eaten and most are highly palatable. The chemical composition and the in vitro digestibility of six species of terricolous lichens commonly eaten by reindeer were measured. Ruminal inoculum was obtained in winter from six free-ranging reindeer that had been grazing on natural pastures in northern Norway. Analysis of the plant parts recovered from their rumens confirmed that the animals had been eating a mixed diet that included both lichens and vascular plants. The chemical composition and the in vitro digestibility of the different species of lichens varied considerably between species and genera. Cetraria islandica, C. nivalis and Cladonia arbuscula were highly digestible [69-77% dry matter (DM)], Stereocaulon paschale was poorly digestible (43% DM), whereas Cladonia stellaris and C. gradlis had an intermediate digestibility (56-57% DM). Mixing ladonia stellaris with vascular plants (50:50) had no effect on the in vitro digestibility of the combined substrates. The in vitro digestibility of Cladonia stellaris in inoculum from two captive reindeer which had had no access to lichens was very low (10% DM). This shows that the source of inoculum used for digestibility trials has a major effect on the apparent digestibility of the substrates. Evidently, the extent to which reindeer are able to utilize lichens depends on the species that are selected and on what the animals have been eating recently.
Tyrosine kinase‐type receptor ErbB4 in chondrocytes: interaction with connective tissue growth factor and distribution in cartilage
Authors: Nawachi Kumiko , Inoue Miho , Kubota Satoshi , Nishida Takashi , Yosimichi Gen , Nakanishi Tohru , Kanyama Manabu , Kuboki Takuo , Yatani Hirofumi , Yamaai Tomoichiro , Takigawa Masaharu
Published: October 2002

In order to identify receptor molecules that participate in the growth and differentiation of chondrocytes, we cloned a number of cDNA fragments from HCS‐2/8 chondrocytic cells, by using tyrosine kinase‐specific primers for amplification. The mRNA expression of one such receptor, ErbB4, was increased by connective tissue growth factor/hypertrophic chondrocyte‐specific gene product (CTGF/Hcs24), which promotes all stages of the endochondral ossification in vitro. ErbB4 expression was observed through all stages of chondrocytic differentiation in vitro, corresponding to the wide distribution of CTGF/Hcs24 target cells. Furthermore, positive signals for erbB4 mRNA were detectable throughout most populations of chondrocytes, in growth and articular cartilage in vivo. These results demonstrate for the first time that ErbB4 is expressed in chondrocytes and may play some roles in chondrocytic growth and differentiation along with CTGF/Hcs24.