bluuebunny/crossref_metadata_2025 huggingface dataset:
Catalytic properties of novel cyclodextrin dimers in the hydrolytic cleavage of p‐nitrophenyl alkanoates
Authors: Luo Mei‐Ming , Xie Ru‐Gang , Xia Ping‐Fang , Tao Ling , Yuan De‐Qi , Zhao Hua‐Ming
Published: August 2002

Novel cyclodextrin (CD) dimers (3a–c) linked by multidentate ligands were prepared by reacting 6‐deoxy‐6‐(hydroxyethylamino)‐β‐CD (2) with p‐ and m‐bis(bromomethyl)benzene and 2,6‐bis(bromomethyl)pyridine, respectively. The catalytic properties of 2, 3b and 3c in the hydrolytic cleavage of p‐nitrophenyl alkanoates, namely acetate (PNPA), butanoate (PNPB), hexanoate (PNPH) and octanoate (PNPO), were examined. CD dimers 3b and 3c showed modest rate enhancements around neutrality. Although the catalytic rate constants (kc) in the presence of 3b or 3c did not vary significantly with the chain length of the esters, the Michaelis constants, KM, for ‘long‐chain’ esters (PNPH and PNPO) were much smaller than those for ‘short‐chain’ esters (PHPA and PNPB), and consequently the selectivity factors (kc/KM) for ‘long‐chain’ esters were much larger than those for ‘short chain’ esters, indicating that the CD dimers had good dimensional recognition ability and substrate selectivity in the hydrolytic cleavage of p‐nitrophenyl alkanoates. Addition of Cu2+ to the reaction media did not have much impact on KM, but led to an appreciable increase in kc, and therefore increases in kc/ku and kc/KM. The monomeric CD compound 2 showed essentially no selectivity in the hydrolysis of these esters. Kinetic consequences are briefly interpreted. Copyright ­© 2001 John Wiley & Sons, Ltd.
Chemistry and technology of 2‐alkenyl azlactones
Authors: Heilmann Steven M. , Rasmussen Jerald K. , Krepski Larry R.
Published: August 2002

The chronology of 2‐alkenyl azlactone research at 3M is discussed in terms of its origination; consideration of economics, overall safety, and opportunities for patent protection; elaboration of the chemistry; and, finally, applying lessons learned toward the development of commercial technologies. The chemistry is dominated by the presence of three electrophilic reaction centers and a readily polymerizable 2‐alkenyl group. Technological development has been focused in four general areas: acrylamide monomers, acrylamide materials, azlactone materials, and polymer modification. Application areas disinclude lithographic printing plates, contact lens materials, adhesives, dispersants for printing inks, and supports for immobilizing enzymes. © 2001 John Wiley & Sons, Inc. J Polym Sci Part A: Polym Chem 39: 3655–3677, 2001
Thermotropic liquid‐crystalline polyesters of 4,4′‐biphenol and phenyl‐substituted 4,4′‐biphenols with 4,4′‐oxybisbenzoic acid
Authors: Bhowmik Pradip K. , Han Haesook , Cebe James J. , Burchett Ronald A.
Published: August 2002

A series of thermotropic polyesters, derived from 4,4′‐biphenol (BP), 3‐phenyl‐4,4′‐biphenol (MPBP), and 3,3′‐bis(phenyl)‐4,4′‐biphenol (DPBP), 4,4′‐oxybisbenzoic acid (4,4′‐OBBA), and other aromatic dicarboxylic acids as comonomers, were prepared by melt polycondensation and were characterized for their thermotropic liquid‐crystalline (LC) properties with a variety of experimental techniques. The homopolymer of BP with 4,4′‐OBBA and its copolymers with either 50 mol % terephthalic acid or 2,6‐naphthalenedicarboxylic acid had relatively high values of the crystal‐to‐nematic transition (448–460 °C), above which each of them formed a nematic LC phase. In contrast, the homopolymers of MPBP and DPBP had low fusion temperatures and low isotropization temperatures and formed nematic melts above the fusion temperatures. Each of these two polymers also exhibited two glass‐transition temperatures, which were associated with vitrified noncrystalline (amorphous) regions and vitrified LC domains, as obtained directly from melt polycondensation. As expected, they had higher glass‐transition temperatures (176–211 °C) than other LC polyesters and had excellent thermal stability (516–567 °C). The fluorescence properties of the homopolymer of DPBP with 4,4′‐OBBA, which was soluble in common organic solvents such as chloroform and tetrahydrofuran, were also included in this study. For example, it had an absorption spectrum (λmax = 259 and 292 nm), an excitation spectrum (λex = 258 and 292 nm with monitoring at 350 nm), and an emission spectrum (λem = 378 nm with excitation at 330 nm) in chloroform. © 2001 John Wiley & Sons, Inc. J Polym Sci Part A: Polym Chem 40: 141–155, 2002
Controlling molecular mobility and ductile–brittle transitions of polycarbonate copolymers
Authors: Wu Jinhuang , Xiao Chaodong , Yee Albert F. , Klug Christopher A. , Schaefer Jacob
Published: August 2002

To control molecular mobility and study its effects on mechanical properties, we synthesized two series of poly(ester carbonate) and polycarbonate copolymers with different linkages: (Bxt)n (x = 3, 5, 7, 9) and (BxT)n (x = 1, 3, 5, 7, 9), where t represents the terephthalate, T represents the tetramethyl bisphenol A carbonate linkages, and B is the conventional bisphenol‐A (BPA) carbonate. These two series of materials have distinct differences in their relaxation behaviors and chain mobility, as indicated by the π‐flip motion of the phenylene rings in the Bx blocks. Uniaxial tensile tests of the copolymers indicate that the brittle–ductile transition (BDT) temperatures of the copolymers are correlated to whether the γ‐relaxation peaks due to the Bx sequence is fully established. The materials possessing more fully established low‐temperature γ peaks give rise to a lower BDT. Also, the locations of the γ peaks are correlated to the ring flips of the Bx blocks of polymer chains. © 2001 John Wiley & Sons, Inc. J Polym Sci Part B: Polym Phys 39: 1730–1740, 2001
Miscibility of polycarbonates with copolymers containing cyclohexylmethacrylate
Authors: Park D. S. , Kim J. H. , Kim M. J. , Kim C. K. , Lee J. W.
Published: August 2002

We prepared various copolymers containing styrene and methacrylates to examine their miscibility with polycarbonates such as bisphenol A polycarbonate (PC), dimethylpolycarbonate (DMPC), and tetramethylpolycarbonate (TMPC). Among the various copolymers examined, poly(methyl methacrylate‐co‐cyclohexylmethacrylate) [P(MMA–CHMA)] copolymers containing proper amounts of cyclohexylmethacrylate (CHMA) formed miscible blends with PC and DMPC, whereas TMPC did not form a miscible blend with P(MMA–CHMA). However, TMPC was miscible with poly(styrene‐co‐cyclohexylmethacrylate) [P(S–CHMA)] copolymers containing less than about 40 wt % CHMA, whereas PC and DMPC were always immiscible with P(S–CHMA). Miscible blends exhibited lower critical solution temperature (LCST)‐type phase behavior. Binary interaction energies were calculated from the observed phase boundaries with lattice–fluid theory combined with a binary interaction model. The quantitative interaction energy of each binary pair indicated that the phenyl ring substitution of polycarbonate with methyl groups did not lead to interactions that were favorable for miscibility with methyl methacrylate (MMA) and CHMA, but it did lead to favorable interactions with styrene. The addition of CHMA to MMA initially increased the LCST but ultimately led to immiscibility with PC and DMPC; however, addition of CHMA to styrene always decreased the LCST with TMPC. The increased LCST of PC or DMPC blends stemmed from intramolecular repulsion between MMA and CHMA, whereas the decreased LCST of TMPC/P(S–CHMA) blends with CHMA content came from negative interaction energy between styrene and CHMA. © 2001 John Wiley & Sons, Inc. J Polym Sci Part B: Polym Phys 39: 1948–1955, 2001
Confocal microscopy studies of shear‐induced coalescence in blends of poly(butyl methacrylate) and poly(2‐ethylhexyl methacrylate)
Authors: Vorobyova Olga , Winnik Mitchell A.
Published: August 2002

This article reports the results of confocal fluorescence microscopy studies of shear‐induced coalescence in binary blends of poly(2‐ethylhexyl methacrylate) (PEHMA; 90 wt %) and poly(butyl methacrylate) (PBMA; 10 wt %). We prepared the blends by casting a mixture of latex dispersions of the components onto a substrate and allowing the film to dry under ambient conditions. The initial morphology of the film was a dispersion of 120‐nm PBMA spheres in a continuous PEHMA matrix. One‐fifth of the PBMA particles were labeled with anthracene, the emission of which we observed with confocal microscopy. The blends were sheared in a parallel‐plate rheometer at 80 and 100 °C for 1 and 10 h. Careful image analysis allowed us to estimate the mean size of the dispersed phase and the width of the size distribution. The results were compared with the theoretical limits of Wu and Taylor. After 10 h of shearing, the mean particle size decreased and the particle distribution became narrower in comparison with the results obtained after 1 h of shearing. We explain this result by inferring that before the sample reached steady‐state morphology, its rate of coalescence was greater than the rate of particle breakup. © 2001 John Wiley & Sons, Inc. J Polym Sci Part B: Polym Phys 39: 2317–2332, 2001
Phase‐separated, conducting composites from polyaniline and benzobisthiazole rigid‐rod polymer
Authors: Tan Loon‐Seng , Simko Sharon R. , Bai Shih Jung , Vaia Richard A. , Taylor Barney E. , Houtz Marlene D. , Alexander Max D. , Spry Robert J.
Published: August 2002

As an alternative method for processing polyaniline (PANI) from its conducting (protonated) state, vacuum casting of PANI from a methanesulfonic acid (MSA) solution provided films with electrical conductivity values of about 130–150 S/cm. In addition, we similarly prepared blended films of PANI · MSA and poly(p‐phenylene benzobisthiazole) (PBZT). This process eliminated the need for a subsequent protonation step and had the additional advantage that the conjugated PBZT may provide alternative conducting pathways. Conductivity values of the composite films ranged from 100 pS/cm to 124 S/cm, and the films displayed critical concentration behavior with a PANI threshold concentration of 2.75% and a critical exponent of 4. Transmission electron micrographs displayed phase‐separated regions with PANI forming a continuous network at high concentrations. Thermogravimetric analysis results demonstrated the thermal and thermooxidative stability advantage of the blends due to the PBZT component. © 2001 John Wiley & Sons, Inc. J Polym Sci Part B: Polym Phys 39: 2539–2548, 2001
Prospective longitudinal study of urinary eosinophil protein X in children with asthma and chronic cough
Authors: Labbé André , Aublet‐Cuvelier Bruno , Jouaville Lionel , Beaugeon G. , Fiani Lilia , Petit Isabelle , Ouchchane Lemlih , Doly M.
Published: August 2002

Airway inflammation is the principal abnormality in asthma and many other respiratory diseases. Eosinophils are the cells primarily involved in this process. The aim of this study was to analyze sequential changes in urinary eosinophil protein X (EPX) a biological marker of eosinophil activation in asthmatic children and chronic coughers, and to confirm the importance of such changes in evaluating the inflammatory process once regular treatment was initiated.

Eighty‐eight asthmatic children (AC), 33 children with chronic cough (CC), and 34 control children were included in the study. All those with respiratory disease underwent allergy tests (serum total IgE, serum‐specific IgE for common allergens, peripheral blood eosinophil (PBE), and skin prick tests) and a pulmonary function test (PFT), and had chest X‐ray and serum eosinophil cationic protein (s‐ECP) and urinary EPX assays. All subjects attended the outpatient clinic every 3 months, irrespective of the treatment prescribed following inclusion in this investigation.

At baseline, urinary EPX concentrations were higher in children with asthma and those with chronic cough than in controls (mean 171.1 and 131.3, respectively, vs. 60.2 μg/mmol creatinine, P < 0.001). CC children had lower eosinophil counts (0.25 vs. 0.39×109/L, P < 0.02) than those with asthma. There was no significant difference between the AC and CC groups in urinary EPX and s‐ECP levels. s‐ECP concentrations were significantly higher (P < 0.01) in atopic vs. nonatopic patients (44 vs. 29.9 ng/mL), but no significant difference was observed for urinary EPX. Concentrations of urinary EPX were significantly correlated with s‐ECP levels (r = 0.24, P < 0.025) and with PBE (r = 0.38, P < 0.01). No correlation was found between urinary EPX values and PFT results. In AC receiving inhaled steroids after the start of the study, there was a significant reduction after 3 months in urinary EPX (−54, P < 0.02). In contrast, there was no significant change in PBE levels.

Urinary EPX concentrations are sensitive, noninvasive technique that could be useful to the clinician in the evaluation of manifestations of airway inflammation. Pediatr Pulmonol. 2001; 31:354–362. © 2001 Wiley‐Liss, Inc.
Cystic fibrosis in three children with bronchopulmonary dysplasia
Authors: Holmgren N.L. , Faro Albert , Gondor M.I. , Orenstein D.M.
Published: August 2002

Cystic fibrosis (CF) and bronchopulmonary dysplasia (BPD) are two common causes of chronic lung disease in children. Patients with BPD or CF often have recurrent respiratory symptoms, failure to thrive, and/or metabolic alkalosis during infancy and childhood. Thus, recognizing the diagnosis of CF in an infant with BPD can be difficult. We present three infants with both BPD and CF. The infants shared a history of respiratory distress and prolonged oxygen requirements. All three also had difficulty gaining weight, even after pancreatic enzyme supplementation was instituted. Metabolic alkalosis was observed in two infants. Previous studies in children with CF suggest that early diagnosis may impact both lung health and nutritional status. A high index of suspicion is necessary for clinicians to identify these children early and intervene with appropriate therapy. Pediatr Pulmonol. 2001; 31:474–477. © 2001 Wiley‐Liss, Inc.
Respiratory syncytial virus immune globulin: Decisions and costs
Authors: Barton Leslie L. , Grant Kathryn L. , Lemen Richard J.
Published: August 2002

A decision analysis was used to evaluate the economic effectiveness of respiratory syncytial virus immune globulin (RSVIG) prophylaxis on selected pediatric populations at risk for developing RSV bronchiolitis or all respiratory illness‐related hospitalizations. We compared costs, outcomes, and cost‐effectiveness of administering RSVIG to no treatment in different pediatric populations, including those at risk of developing RSV‐bronchiolitis and those at risk of developing any respiratory illness‐related hospitalization.

We observed that if only infants at high risk of severe RSV infections received treatment with RSVIG, a calculated cost saving of about $27,000 per hospitalization prevented were realized. If the Food and Drug Administration (FDA)‐approved indications for RSVIG were followed, the cost to prevent one hospitalization due to RSV bronchiolitis would be over $53,000. If the aim, however, was to prevent all respiratory illness‐related hospitalizations for this broader population, a much lower cost ($4,000) to prevent one hospitalization would result. In this situation, cost neutrality was possible, with a therapy cost of $2,843 compared to the actual average therapy cost of $4,444. Sensitivity analysis showed that the model was relatively insensitive to all variables, with the exceptions of costs related to RSVIG and intensive care unit (ICU) admissions.

We conclude that RSVIG resulted in cost savings if therapy were reserved for the infants who are at highest risk for developing severe RSV infections. RSVIG is not cost‐effective for preventing RSV bronchiolitis when used according to the FDA‐approved indications. Education that emphasizes frequent hand‐washing, avoidance of passive smoking, and lessening exposure to sick children remains the least expensive prevention tool. Pediatr Pulmonol. 2001; 32:20–28. © 2001 Wiley‐Liss, Inc.
Work of breathing associated with pressure support ventilation in two different ventilators*†
Authors: Sanders Ronald C. , Thurman Tracy L. , Holt Shirley J. , Taft Kathleen , Heulitt Mark J.
Published: August 2002

The purpose of this study was to compare the work of breathing during pressure support ventilation (PSV) with positive end expiratory pressure (PEEP) utilizing the Siemens SV300® (SV300) and Dräger Evita 4® (EV4) ventilators. Our hypothesis was that patients' work of breathing (WOBP) would be unchanged in PSV utilizing flow triggering (FT) in both the SV300® and EV4®. We compared two ventilators using six healthy, intubated, sedated, spontaneously breathing pigs weighing approximately 10 kg each. WOBP (j/L) and ventilator work of breathing (WOBV) (j/L) were measured using a portable monitor which utilizes an esophageal balloon and flow transducer. Each breath was further analyzed for duration of inspiratory effort and negative deflection of pressure needed to trigger PSV. Animals were studied with the SV300® and EV4® on a pressure support of 5 cmH2O and PEEP settings of 0 and 5 cmH2O. Data were analyzed using the Wilcoxon signed rank test with significance set at P ≤ 0.05

WOBP was 90% (PS 5, PEEP 0) and 52% (PS 5, PEEP 5) lower on the SV300® compared to the EV4®. WOBV was 94% (PS 5, PEEP 0) and 39% (PS 5, PEEP 5) higher on the SV300® when compared to the EV4®. The change in airway pressure (delta p) from baseline and most negative deflection of pressure were greater with the EV4® as compared to the SV300®, although delta pressure was not found to be statistically significant on PS of 5 cmH2O and PEEP of 5 cmH2O. The SV300® also had shorter duration of inspiratory effort from initiation of breath to most negative deflection of pressure and to maximum flow than the EV4®.

In conclusion, these results suggest there are significant differences in WOBP between the SV300® and EV4® ventilators. Response time of the ventilators may explain the differences in duration of inspiratory effort and the patient's work of breathing and thus may have an impact on weaning time for ventilated patients. Pediatr Pulmonol. 2001; 32:62–70. © 2001 Wiley‐Liss, Inc.
Airway in the oculo‐auriculo‐vertebral spectrum: Two cases and a review of the literature
Authors: McCarthy Vincent P. , Zimo Deborah A. , Lucas Melinda A.
Published: August 2002

Two patients with oculo‐auriculo‐vertebral syndrome and multiple airway anomalies are presented. Both patients had esophageal atresia with a distal tracheoesophageal fistula and tracheomalacia due to innominate artery compression. Pulmonary hypoplasia, obstructive sleep apnea, and a laryngeal anomaly were also noted. The literature of airway anomalies and obstructive sleep apnea described in association with the oculo‐auriculo‐vertebral spectrum is reviewed. Pediatr Pulmonol. 2001; 32:250–256. © 2001 Wiley‐Liss, Inc.
Corticosteroid therapy reversed progressive chronic granulomatous lung disease following deterioration on interferon‐γ treatment
Authors: Halamish Ariel , Klar Aharon , Shoseyov David , Blinder George , Hurvitz H.
Published: August 2002

We describe a patient who suffered from chronic progressive granulomatous lung disease. He had no clinical or microbiological evidence of infection. After failure of treatment with interferon‐γ and trimethoprim‐sulfamethoxazole, he responded dramatically to corticosteroids. Pediatr Pulmonol. 2001; 32:257–260. © 2001 Wiley‐Liss, Inc.
Calcium, dairy products, and the risk of prostate cancer
Authors: Tavani Alessandra , Gallus Silvano , Franceschi Silvia , La Vecchia Carlo
Published: August 2002

BACKGROUND

Calcium intake has been suggested to play a role in the etiology of prostate cancer, since it is inversely related to vitamin D levels, which, in turn, would have an antiproliferative effect on human cancer cell lines. The hypothesis that high calcium and low vitamin D levels are associated with prostate cancer risk, however, remains unconvincingly demonstrated.

METHODS

This relation was investigated in a case—control study of prostate cancer conducted in Northern Italy between 1985 and 1992 on 288 cases and 762 controls admitted to hospital for acute non‐neoplastic diseases.

RESULTS

No significant relation was found for calcium intake: compared to the lowest quintile of intake, the multivariate odds ratios (OR) of prostatic cancer, after adjusting for age, study center, education, body mass index, and meat intake, for increasing intake quintiles were 1.21, 0.68, 0.64, 1.12, with no trend in risk. The OR was 0.99 for an increment of 500 mg per day of calcium. The risk estimates were consistent in two strata of age (<65 and ≥65 years at diagnosis).

CONCLUSIONS

Our results do not support an association between calcium and the risk of prostate cancer. However, the present study cannot address the effect of calcium in the ranges where an increased risk of prostate cancer has been noted previously, and with specific reference to advanced disease. Prostate 48:118–121, 2001. © 2001 Wiley‐Liss, Inc.
Impact of preoperative serum PSA level from 0 to 10 ng/ml on pathological findings and disease‐free survival after radical prostatectomy
Authors: Shekarriz Bijan , Upadhyay Jyoti , Bianco Fernando J. , Tefilli Marcos V. , Tiguert Rabi , Gheiler Edward L. , Grignon David J. , Pontes J. Edson , Wood David P.
Published: August 2002

Background

To determine the impact of various preoperative serum prostate specific antigen (PSA) levels in the range from 0.1 to 10 ng/ml on pathological stage and disease‐free survival after radical prostatectomy.

Methods

We selected a cohort of 585 patients who underwent radical prostatectomy between 1991–1996 for clinically localized prostate cancer and presented with preoperative serum PSA levels from 0.1 to 10 ng/ml.

Results

Pathological organ‐confined disease was present in 57.6% of patients. The rate of organ‐confined disease decreased from an average of 85% for patients with a PSA value < 2 ng/ml, to 46.8% for patients with a PSA value > 7 ng/ml. We found statistically significant correlations between preoperative serum PSA level and overall pathological stage (P = 0.001), pathologically organ‐confined disease (P = 0.001), margin positive rates (P = 0.001), extra prostatic extension (P = 0.001), and seminal vesicle invasion (P = 0.001). The overall disease‐free survival rate was 87%, with a median follow up of 42.4 months. Disease free survival was significantly better for patients with PSA up to 4 ng/ml (P = 0.005).

Conclusions

Our data suggests that PSA detection programs should strive to detect prostate cancer in men before the PSA level rises above 7 ng/ml. In addition, since patients with a PSA level < 4 ng/ml had better disease‐free survival rates than those with a PSA level between 4.1–10 ng/ml, eliminating an arbitrary cutoff of 4 ng/ml, may lead to improved disease‐free survival. Prostate 48:136–143, 2001. © 2001 Wiley‐Liss, Inc.
Growth of heterotopic LNCaP prostate cancer tumor in nude mice is not affected by dietary calcium
Authors: Balaji K.C. , Huryk R.F. , Verhulst S. , Fair W.R.
Published: August 2002

BACKGROUND

We attempted to provide experimental evidence linking increased dietary calcium to progression of prostate cancer, as suggested by some epidemiological studies, using a heterotopic prostate cancer nude mice model.

METHODS

Twenty heterotopic LNCaP prostate cancer tumor bearing nude mice were randomly assigned to one of the four groups: (I) high fat/low calcium diet, (II) high fat and high calcium diet, (III) high fat diet fortified with Vitamin D3, and (IV) high fat and high calcium diet fortified with Vitamin D3. In addition to weekly animal weights and tumor size measurements, the serum prostate specific antigen (PSA), 25‐hydroxy Vitamin D3, calcium, phosphorus, total protein, albumin (to account for bound calcium) [1], and serum alkaline phosphatase (a measure of bone loss) [2] were determined at the termination of experiments.

RESULTS

Although the serum calcium and 25‐hydroxy Vitamin D3 were significantly higher in groups III and IV compared to groups I and II (P < 0.05), there was no significant difference between the tumor growth rates, final tumor weights (P = 0.9), and the serum PSA levels (P = 0.94) between the four groups.

CONCLUSIONS

The results suggest that dietary calcium does not significantly affect the growth of heterotopic LNCaP prostate cancer in nude mice. Prostate 48:265–273, 2001. © 2001 Wiley‐Liss, Inc.
Effect of an EGF‐R selective tyrosine kinase inhibitor and an anti‐androgen on LNCaP cells: Identification of divergent growth regulatory pathways
Authors: Jones Helen E. , Barrow Denise , Dutkowski Carol M. , Goddard Lindy , Smith Christopher , Harper Maureen E. , Nicholson Robert I.
Published: August 2002

BACKGROUND

The effect of an EGF‐R selective tyrosine kinase (EGF‐RTK) quinazoline inhibitor ZM252868 was determined on the androgen‐sensitive human prostatic tumour cell line LNCaP, which can also respond via the EGF‐R‐regulated growth pathway for cell proliferation. Potential interaction or ‘cross‐talk’ between steroid and the growth factor mitogen‐activated protein kinase (MAPK) signalling pathway was also investigated.

METHODS

The responses of LNCaP cells to various growth factors in the absence and presence of the EGF‐RTK inhibitor and/or steroid and anti‐androgen Casodex, was determined using cell population analysis. The effect of the inhibitor on the expression of androgen receptor, EGF‐R and activated MAPK was assessed immunocytochemically and changes in the MAPK signalling cascade were also determined using Western blotting techniques.

RESULTS

The ZM252868 inhibitor had no effect on LNCaP basal growth. At 100 nM and 1 μM concentrations, the inhibitor reduced the marked EGF‐ and TGF‐α‐stimulated LNCaP cell growth by 60% and to basal levels, respectively. Both bFGF‐ and 5α‐DHT‐stimulated growth were unaffected in this concentration range. The inhibitor (1 μM) decreased the expression of immunoreactive EGF‐R but had no effect on androgen receptor levels. Activation of MAPK by EGF was noted, being down‐regulated by the inhibitor at a concentration of 1 μM. MAPK was not activated by 5α‐DHT. The anti‐androgen Casodex reduced 5α‐DHT‐stimulated cell growth but had no effect on EGF‐R mediated LNCaP growth or EGF‐stimulated activated MAPK activity. Treatment with EGF and 5α‐DHT in combination produced an additive effect on cell proliferation, with the anti‐androgen and the EGF‐RTK inhibitor only reducing the 5α‐DHT‐ or EGF‐stimulated portion of growth, respectively.

CONCLUSIONS

The study demonstrated the efficacy and selectivity of the ZM252868 inhibitor in inhibiting EGF‐R mediated LNCaP cell growth. Additionally, no interaction between androgen and EGF‐R mediated growth pathways was determined. Prostate 49:38–47, 2001. © 2001 Wiley‐Liss, Inc.
Model of three‐dimensional structure of vitamin D receptor and its binding mechanism with 1α,25‐dihydroxyvitamin D3
Authors: Rotkiewicz Piotr , Sicinska Wanda , Kolinski Andrzej , DeLuca Hector F.
Published: August 2002

Comparative modeling of the vitamin D receptor three‐dimensional structure and computational docking of 1α,25‐dihydroxyvitamin D3 into the putative binding pocket of the two deletion mutant receptors: (207–423) and (120–422, Δ [164–207]) are reported and evaluated in the context of extensive mutagenic analysis and crystal structure of holo hVDR deletion protein published recently. The obtained molecular model agrees well with the experimentally determined structure. Six different conformers of 1α,25‐dihydroxyvitamin D3 were used to study flexible docking to the receptor. On the basis of values of conformational energy of various complexes and their consistency with functional activity, it appears that 1α,25‐dihydroxyvitamin D3 binds the receptor in its 6‐s‐trans form. The two lowest energy complexes obtained from docking the hormone into the deletion protein (207–423) differ in conformation of ring A and orientation of the ligand molecule in the VDR pocket. 1α,25‐Dihydroxyvitamin D3 possessing the A‐ring conformation with axially oriented 1α‐hydroxy group binds receptor with its 25‐hydroxy substituent oriented toward the center of the receptor cavity, whereas ligand possessing equatorial conformation of 1α‐hydroxy enters the pocket with A ring directed inward. The latter conformation and orientation of the ligand is consistent with the crystal structure of hVDR deletion mutant (118–425, Δ [165–215]). The lattice model of rVDR (120–422, Δ [164–207]) shows excellent agreement with the crystal structure of the hVDR mutant. The complex obtained from docking the hormone into the receptor has lower energy than complexes for which homology modeling was used. Thus, a simple model of vitamin D receptor with the first two helices deleted can be potentially useful for designing a general structure of ligand, whereas the advanced lattice model is suitable for examining binding sites in the pocket. Proteins 2001;44:188–199. © 2001 Wiley‐Liss, Inc.
Computer modeling and molecular dynamics simulations of ligand bound complexes of bovine angiogenin: Dinucleotide topology at the active site of RNase a family proteins
Authors: Madhusudhan M.S. , Sanjeev B.S. , Vishveshwara S.
Published: August 2002

We have undertaken the modeling of substrate‐bound structures of angiogenin. In our recent study, we modeled the dinucleotide ligand binding to human angiogenin. In the present study, the substrates CpG, UpG, and CpA were docked onto bovine angiogenin. This was achieved by overcoming the problem of an obstruction to the B1 site by the C‐terminus and identifying residues that bind to the second base. The modeled complexes retain biochemically important interactions. The docked models were subjected to 1 ns of molecular dynamics, and structures from the simulation were refined by using simulated annealing. Our models explained the enzyme's specificity for both B1 and B2 bases as observed experimentally. The nature of binding of the dinucleotide substrate was compared with that of the mononucleotide product. The models of these complexes were also compared with those obtained earlier with human angiogenin. On the basis of the simulations and annealed structures, we came up with a consensus topology of dinucleotide ligands that binds to human and bovine angiogenins. This dinucleotide conformation can serve as a starting model for ligand‐bound complex structures for RNase A family of proteins. We demonstrated this capability by generating the complex structure of CpA bound to eosinophil‐derived neurotoxin (EDN) by fitting the consensus topology of CpA to the crystal structure of native EDN. Proteins 2001;45:30–39. © 2001 Wiley‐Liss, Inc.
Photochemical transformation of acifluorfen under laboratory and natural conditions
Authors: Vialaton Delphine , Baglio Daniela , Paya‐Perez Ana , Richard Claire
Published: August 2002

Acifluorfen was irradiated in pure water at various excitation wavelengths and pH values. Numerous photoproducts were obtained which were identified by [1H]NMR and /or HPLC–MS/MS. The main reaction pathways were photo‐decarboxylation, photo‐cleavage of the ether bonding with formation of phenolic compounds, photo‐dechlorination and photo‐Claisen type rearrangement. Decarboxylation was observed in acidic and neutral media whereas cleavage of the ether bonding dominated in basic media. The photo‐Claisen type rearrangement only occurred on excitation at short wavelengths. The quantum yield of photolysis was significantly lower at 313 nm (6.1 × 10−5) than at 254 nm (2.0 × 10−3). The photoreactivity of acifluorfen was then studied in conditions approaching environmental conditions. Acifluorfen was dissolved in pure water, in water containing humic substances or in a natural water, and exposed to solar light in June at Clermont‐Ferrand (latitude 46 °N). In pure water, the half‐life was estimated at 10 days and photo‐decarboxylation accounted for 30% of the conversion. The presence of humic substances (10 mg litre−1) did not affect the rate of photo‐transformation. However, the half‐life of acifluorfen dissolved in the natural water was only 6.8 days.

© 2001 Society of Chemical Industry
Peptide T revisited: conformational mimicry of epitopes of anti‐HIV proteins
Authors: Picone Delia , Rivieccio Angela , Crescenzi Orlando , Caliendo Giuseppe , Santagada Vincenzo , Perissutti Elisa , Spisani Susanna , Traniello Serena , Temussi Piero Andrea
Published: August 2002

Peptide T (ASTTTNYT), a fragment corresponding to residues 185–192 of gp120, the coat protein of HIV, is endowed with several biological properties in vitro, notably inhibition of the binding of both isolated gp120 and HIV‐1 to the CD4 receptor, and chemotactic activity. Based on previous nuclear magnetic resonance (NMR) studies performed in our laboratory, which were consistent with a regular conformation of the C‐terminal pentapeptide, and SAR studies showing that the C‐terminal pentapeptide retains most of the biological properties, we designed eight hexapeptides containing in the central part either the TNYT or the TTNY sequence, and charged residues (D/E/R) at the two ends. Conformational analysis based on NMR and torsion angle dynamics showed that all peptides assume folded conformations, albeit with different geometries and stabilities. In particular, peptides carrying an acidic residue at the N‐terminus and a basic residue at the C‐terminus are characterized by stable helical structures and retain full chemotactic activity. The solution conformation of peptide ETNYTR displays strong structural similarity to the region 19–26 of both bovine pancreatic and bovine seminal ribonuclease, which are endowed with anti‐HIV activity. Moreover, the frequent occurrence, in many viral proteins, of TNYT and TTNY, the two core sequences employed in the design of the hexapeptides studied in the present work, hints that the sequence of the C‐terminal pentapeptide TTNYT is probably representative of a widespread viral recognition motif. Copyright © 2001 European Peptide Society and John Wiley & Sons, Ltd.
Progress in the methods of analysis of restricted distortional buckling of composite bridge girders
Authors: Ronagh Hamid R
Published: August 2002

The problem of restricted distortional buckling (RDB) is described in this paper, together with an overview of the history of progress in this area over recent years. A simple method for the distortional buckling analysis of composite steel/concrete bridge girders is then revisited here in a new form. The approach is based on the analogy between the buckling phenomenon, and that of a beam on an elastic foundation that is well known in structural engineering. In this analogy, the bottom flange of the steel joist is simulated as a beam that is resting on the elastic foundation of the web, and that is subjected to an axial force whose distribution can be determined from the bending moment diagram of the composite bridge girder. In order to present the problem mathematically and simply, a simple finite element model with two nodes and three degrees of freedom per node is developed. The method is then used to provide design curves for a range of loading patterns. Owing to the simplicity and clarity of the model, it may is useful for implementation in design practice.
Shock spectra and damage boundary curves for hyperbolic tangent cushioning system and their important features
Authors: Wang Zhi‐Wei
Published: August 2002

By applying the method suggested in the author's previous paper, shock spectra and damage boundary curves are investigated for a hyperbolic tangent cushioning system under the action of rectangular, half‐sine, terminal‐peak saw‐tooth and initial‐peak saw‐tooth acceleration pulses, respectively. The shock spectrum is affected not only by the damping parameter but also by the dimensionless pulse peak, and both the damping parameter and the dimensionless fragility influence the damage boundary curve for this cushioning system. Some important features of a hyperbolic tangent cushioning system that differs from a tangent cushioning system are discussed in detail. Copyright © 2001 John Wiley & Sons, Ltd.
Influence of PET bottle weight, closure performance and filling Technique on the oxygen content of soya cooking oil
Authors: de Oliveira Léa Mariza , Sarantópoulos Claire , Bordin Maurício , Nakandakari Yuri
Published: August 2002

The use of PET bottles for edible oil in Brazil is increasing but there is a trend to reduce bottle weight for economic reasons, which decreases the oxygen barrier of the package. The barrier performance of a 20 g PET bottle for 900 ml soya oil, submitted to gas flushing with gaseous N2 and pressurization with liquid N2, was compared with a 27 g PET conventional bottle. During 8 months storage at 25°C the internal pressure, dissolved oxygen and oxygen in the headspace were evaluated and did not change significantly. Liquid N2 pressurization did not improve the efficiency of reducing O2 in the headspace compared to N2 gas flushing. Copyright © 2001 John Wiley & Sons, Ltd.
Organizational correlates of perceptions of quality outcomes for ISO 9000 registration: a preliminary analysis
Authors: Bellamy Alphonso R. , Fowler Rhonda , Boyless John
Published: August 2002

The purpose of this study was to explore the impact that the organizational factors of planning and implementation processes have on individual perceptions of quality outcomes related to The International Organization for Standardization (ISO) 9000 registration. Results indicate that the planning and implementation processes of ISO 9000 registration do indeed have an influence on the ways in which individuals evaluate the impact that registration has on quality outcomes. The study further showed that personality factors also influence perceptual judgments of ISO 9000 registration success. Copyright © 2001 John Wiley & Sons, Ltd.
Statistical sampling – practical advice in the field of quality assurance
Authors: Scott Martin
Published: August 2002

Although many people who conduct experiments accept that in certain scenarios some sort of sampling is necessary, it is often unclear why a clear and pre‐defined sampling process is so important, and indeed, why it is needed at all. As a consequence, statisticians are often called in, sometimes at the last minute, to select the most ‘appropriate’ sample using some sort of complex computer algorithm behind closed doors. The method of selecting the sample remains a secret to those outside the realms of statistics, thereby making the process of sampling and statistics in general, ever more elusive to the nonstatistician and thus ensuring that the future prospects of careers for statisticians remain as attractive as ever. Is the process of sampling difficult to understand and implement? The answer is NO. In fact, the concept of sampling is simple and the methods far from complicated. It is often the case, however, that topics of a mathematical nature are poorly explained and are consequently poorly understood. It is thus sometimes necessary that an appropriate introduction and helpful explanation regarding their use, process of implementation, and possible benefits be made available. Copyright © 2001 John Wiley & Sons, Ltd.
Some characteristics of a good monitor
Authors: Nickols Pamela Charnley
Published: August 2002

Do you know anyone like this?

Strong and healthy, patient, sociable, persuasive, knowledgeable, determined, hardworking, numerate and well trained, unsociable, nosey and doggedly persistent possessed of psychic powers. If so you may wish to recommend that he or she becomes a monitor. Copyright © 2001 John Wiley & Sons, Ltd.
What's new?
Authors: Bohaychuk Wendy
Published: August 2002

The What's New? section in the Quality Assurance Journal aims to draw your attention to items of importance to QA professionals. Each item will be linked to the relevant internet address which you might add to your ‘favorites’ folders. If there is any other new information which should be brought to the attention of readers, please let us know by e‐mailing wbohaychuk@gcrpc.com Copyright © 2001 John Wiley & Sons, Ltd.
Multivariate monitoring of batch process startup
Authors: Wurl Robin C. , Albin Susan L. , Shiffer Irwin J.
Published: August 2002

A batch process is finite in duration and can be separated into two stages: startup and production. We develop a methodology to monitor a batch process during the startup stage to reduce the length of the startup stage. We focus on processes that are characterized by multiple process parameters and product characteristics. Because of the complex interdependencies characterizing the process parameters and product characteristics, it is more effective to evaluate them simultaneously. To address the multivariate nature of the process we use a multivariate statistical model: PLS (Projection to Latent Structures). PLS has been applied to several applications in statistical process monitoring. We present a new application of PLS to the startup stage of a batch process. Iterative adjustments made during startup in search of an acceptable production zone consume considerable amounts of material, labor and equipment time. We develop a monitoring procedure to reduce the time as well as the number of iterations and adjustments needed for startup. A PLS model is constructed, using baseline data, to characterize the relationship among process parameters during good production. The startup stage is monitored using the PLS characterization to determine if the process is consistent with good production. We illustrate the improved startup operations with an example from a batch process in filament extrusion, the application that motivates this work. Copyright © 2001 John Wiley & Sons, Ltd.
QED‐SCF, MCSCF, and coupled‐cluster methods in quantum chemistry
Authors: Ohsaku Tadafumi , Yamaguchi Kizashi
Published: August 2002

We investigate a method of combining the techniques of quantum chemistry with QED. In our theory, we treat the N‐electron system and the Dirac sea on an equal footing; we regard both of them as the dynamical degrees of freedom of a many‐body system. After the introduction of our QED‐SCF method, the QED‐SCF solutions are classified on the basis of group‐theoretical operations such as time‐reversal, parity and O(3) rotational symmetry. The natural orbitals of general QED‐SCF solutions are determined by diagonalizing the first‐order density matrix. Thus, we obtain the possibility of treating the system under strong QED effect by the methods of quantum chemistry, such as QED‐MCSCF and QED coupled‐cluster approaches. © 2001 John Wiley & Sons, Inc. Int J Quantum Chem, 2001
On the calculation of arbitrary multielectron molecular integrals over Slater‐type orbitals using recurrence relations for overlap integrals. III. Auxiliary functions \documentclass{article}\pagestyle{empty}\begin{document}$Q_{nn'}^{q}$\end{document} and \documentclass{article}\pagestyle{empty}\begin{document}$G_{-nn'}^{q}$\end{document}
Authors: Guseinov I. I. , Mamedov B. A.
Published: August 2002

The auxiliary functions \documentclass{article}\pagestyle{empty}\begin{document}$Q_{nn'}^{q}(p,pt)$\end{document} and \documentclass{article}\pagestyle{empty}\begin{document}$G_{-nn'}^{q}(p_{a},p,pt)$\end{document} which are used in our previous paper [Guseinov, I. I.; Mamedov, B. A. Int J Quantum Chem 2001, 81, 117] for the computation of multicenter electron‐repulsion integrals over Slater‐type orbitals (STOs) are discussed in detail, and the method is given for their numerical computation. The present method is suitable for all values of the parameters pa, p, and pt. Three‐ and four‐center electron‐repulsion integrals are calculated for extremely large quantum numbers using relations for auxiliary functions obtained in this paper. © 2001 John Wiley & Sons, Inc. Int J Quantum Chem, 2001
Anomalous energy losses for light projectiles traversing a polyvinylformyl resin*
Authors: Porter L. E.
Published: August 2002

Measurements of the stopping powers of the polyvinylformyl resin known as formvar for 0.67–1.75 MeV protons, 1.19–3.02 MeV alpha particles, and 3.9–10.4 MeV 7Li ions have been analyzed in terms of modified Bethe–Bloch theory for the purpose of extracting values of the dominant parameters of the formalism employed. These parameters are the target mean excitation energy and the Barkas‐effect parameter, plus a single effective‐charge parameter to characterize the interactions of 4He and 7Li projectiles with the target. Whereas results for the Barkas‐effect parameter agreed well with the expected value of 1.4±0.1, results for the mean excitation energy lay about 20% below the value of 71.9 eV based on the assumption of linear additivity of stopping effects. Speculation as to the source of this difference is offered. © 2001 John Wiley & Sons, Inc. Int J Quantum Chem, 2001
Theoretical study on the electronic structure and properties of synthetic MoFe3S3 compounds*
Authors: Stavrev K. K. , Urahata S. , Herz T. , Han J. , Coucouvanis D.
Published: August 2002

We examine the electronic structure of a series of MoFe3S3 compounds whose spectroscopic and structural parameters have been recently published (J. Han, K. Beck, N. Ockwig, D. Coucouvanis, J Am Chem Soc 1999, 121, 10448). The synthetic Mo/Fe/S compounds under examination are close structural and functional analogs of essential parts of the FeMo‐cofactor in the enzyme nitrogenase. Using the ZINDO program and the projected unrestricted Hartree–Fock (PUHF) method, we have demonstrated that these compounds exhibit antiferromagnetic coupling between the metal atoms, with calculated triplet and singlet ground states. The metal atoms are found in reduced oxidation states, namely Mo(III), Fe(II), and Fe(I), in agreement with the experimental isomer shifts and the Mössbauer data previously reported. The addition of carbonyl groups to the MoFe3S3 clusters leads to a withdrawal of electron density from the Mo/Fe/S core and thus affects the strength of the metal–metal and metal–sulfur bonds in the compounds. We also show that the removal of pyridine from the coordination of the Mo atom has a notable effect on the electron delocalization in the Mo/Fe/S core and may lead to preferential localization of the electron density on the iron atoms. © 2001 John Wiley & Sons, Inc. Int J Quantum Chem, 2001
Molecular magnetism via resonating valence bonds for conjugated radicals and selected transition metal complexes
Authors: Klein D. J. , March N. H.
Published: August 2002

Currently there is considerable interest in the nature of exchange interactions leading to unpaired electrons in molecular and cluster magnets. Here, the focus is largely at a qualitative level, via a novel “mean‐field” resonance‐theoretic view, to deal with exchange couplings, so as to allow unpaired electrons in either (or both of) the π‐ and σ‐parts of a (largely organic) bipartite (or alternate) molecular network. The (quantitative) number and (qualitative) location of unpaired spins are dealt with by this simple approach, which also offers some (qualitative) information on the occurrence of low‐lying higher‐spin states. To illustrate the approach it is applied to a variety of systems where the spin sources are conjugated π‐network molecules and polymers, carbenes, variously defected graphites, and a few species involving transition metals, especially Cu. The discussion deals not only with traditional conjugated organics compounds but also with selected inorganic species. © 2001 John Wiley & Sons, Inc. Int J Quantum Chem, 2001