bluuebunny/crossref_metadata_2025 huggingface dataset:
Precision associated with determination of dirt content of natural rubber
Authors: Ehabe E. , Ngolemasango F. , Bonfils F. , Sainte‐Beuve J.
Published: August 2002

The precision associated with determination of dirt in natural rubber is low even when similar testing procedures are applied. All measurements leading to this estimation involve the use of an analytical balance. For this reason the contribution of associated errors to the ultimate precision of dirt measurements was evaluated using analytical balances of varying degrees of precision. A mathematical model was proposed to estimate the compound standard error associated with dirt measurements, which was found to be ±0.001 mg. This signifies that, during dirt assay, the masses of test portions, empty sieves, and sieves containing dirt must be estimated to at least 3 significant figures. This error would further decrease with an increase in the quantity of dirt assayed. Prolonged maturation of coagula reduced the length of rubber chains, thus increasing the ease of dissolution of test portions during dirt analysis. Higher molar mass samples were mostly associated with poor reproducibility of dirt and macrogel content determinations. Increasing the mass of test portions improved the precision of dirt measurements, though the recommended sizes of these portions should be a compromise of economic considerations and practical testing conditions. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 81: 957–962, 2001
Phosphate‐containing flame‐retardant polymers with good compatibility to polypropylene. I. The effect of phosphate structure on its thermal behavior
Authors: Chiang Wen‐Yen , Hu Howard C.‐H.
Published: August 2002

Phosphate‐containing flame‐retardant polymers were synthesized via a partial‐substitution reaction of poly(vinyl acetate) with stearylphosphonic chloride (SPPC) and diethylchlorophosphate in various substitution ratios. SPPC had been previously synthesized from phosphonic dichloride and stearyl alcohol. The synthesized SPPC and the flame‐retardant polymer products were characterized by Fourier transform infrared (FTIR) spectra analysis. The quantitative analysis of phosphorus in the polymer products was carried out by EDS (Energy Dispersion Spectrummeter) analysis. The real substitution ratios of the polymer products were estimated by the atomic number ratio of carbon and phosphate in products from EDS data. Variations in the glass‐transition temperature and thermal‐decomposition temperature of the products were investigated. The char of polymer products produced after thermogravimetric analysis (TGA) was also analyzed by FTIR, and the results show that different phosphate substitution leads to different char developments during the heating of TGA. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 81: 1125–1135, 2001
Cyclic acetals: Synthesis and polymerization
Authors: Socha František , Dobáš Ivan , Šňupárek Jaromír
Published: August 2002

Mixtures of 5‐membered and 6‐membered 2‐vinyl (2‐propenyl or 2‐isopropyl)‐4‐hydroxymethylene or 5‐hydroxy‐substituted cyclic acetals were synthesized by the reaction of aldehydes with glycerol. Reesterification of the hydroxyl group in position 4 or 5 was achieved using methyl methacrylate. The compounds were subjected to radical copolymerization using different initiating systems. Both radical copolymerization and ring cleavage were observed to be dependent on the reaction conditions. The ring cleavage was confirmed on model compounds of 2‐substituted 5‐membered and 6‐membered cyclic acetals without any polymerizable substituent. The rate of the ring opening was measured and compared to the rate of copolymerization. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 81: 2875–2880, 2001
Monomer consumption rates during gelation at various temperatures: A fast transient fluorescence study
Authors: Pekcan Ö. , Kaya D.
Published: August 2002

The gelation during free‐radical crosslinking copolymerization (FCC) of methyl methacrylate (MMA) and ethylene glycol dimethacrylate (EGDM) was studied by using fast transient fluorescence (FTRF) technique. Pyrene (Py) was used as a probe for the FTRF experiments. Fluorescence lifetimes of Py from its decay traces were measured and used to monitor the gelation process at various temperatures. MMA consumption rates were measured during gelation process by using the Stern–Volmer model. Gelation activation energy ΔEG was measured and found to be 15.6 kcal mol−1. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 81: 3161–3168, 2001
Copolymers of chosen alkyl methacrylates with N‐phenylmaleimide and N‐(4‐halogenphenyl)maleimides: A UV‐aging study
Authors: Ryttel Anna
Published: August 2002

Homopolymers and copolymers of ethyl and butyl methacrylates with N‐phenylmaleimide, N‐(4‐chlorophenyl)maleimide, and N‐(4‐bromophenyl)maleimide were synthesized by free‐radical bulk polymerization with benzoyl peroxide as the initiator. The content of imide in the copolymers was about 5–10 or 7.5 wt %. The homopolymers and copolymers were irradiated with ultraviolet (UV) light in a climatic test chamber for various periods to study their aging behavior. After 100, 250, and 500 h, the structure, thermal stability, chemical resistance, and some physicomechanical properties were examined. The influence of UV radiation time on structure and the investigated properties of the homopolymers and copolymers were studied. The experimental results indicate that all investigated copolymers were resistant to UV radiation after 500 h. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 81: 3244–3250, 2001
Synthesis and characterization of poly(N‐vinyl pyrrolidone‐alt‐maleic anhydride): Conjugation with bovine serum albumin
Authors: Veron L. , Revol M. , Mandrand B. , Delair T.
Published: August 2002

Alternate N‐vinyl pyrrolidone/maleic anhydride (NVPMA) copolymers were obtained by radical solution polymerization in dioxane with various MA contents in the monomer feed. The conversion of each monomer was monitored by proton nuclear magnetic resonance spectroscopy (1H NMR), and the kinetics investigation showed that both monomers had identical polymerization rates if both monomers were present in the reaction mixture. The presence of excess NVP in the polymerization medium increased the kinetics of the polymerization and the molar masses of the resulting polymers. This increase was attributed to a cosolvent effect due to NVP, which is a better solvent for the polymer than dioxane. The hydrolysis rate constant of the polymers increased with pH, and NVPMA copolymers were more prone to hydrolysis (by a factor 10) than the methyl vinyl ether ones. Finally, the immobilization of bovin serum albumin (BSA) was investigated. A 25 mM phosphate buffer (pH 5.5) was the best medium to covalently bind 5 BSA molecules onto a 29 kDa NVPMA copolymer and 13 BSA molecules onto a 58 kDa sample, with grafting efficiencies > 90%. Noncovalent interactions with the hydrolyzed form of the polymer and BSA occured at pHs lower than the isoelectric point of BSA, and the resulting complexes were insoluble in water. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 81: 3327–3337, 2001
Synthesis and characterization of sulfonated poly(phenylene oxides) as membranes for polymer electrolyte membrane fuel cells
Authors: Vishnupriya B. , Ramya K. , Dhathathreyan K. S.
Published: August 2002

The synthesis of a thermally stable proton conducting polymer based on poly(phenylene oxide) (PPO) was carried out using 2,6‐dimethylphenol (DMP) and 2‐allylphenol (AP) as monomers. The copolymers using the two monomers were prepared with DMP to AP molar ratios of 20:80, 40:60, 60:40, and 80:20. The polymers and the copolymers were blended with poly(vinylidene fluoride) and cast as membranes. All the membranes were sulfonated and characterized for their suitability as a polymer electrolyte membrane. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 83: 1792–1798, 2002
Oxygen enrichment from air through multilayer thin low‐density polyethylene films
Authors: Huang Mei‐Rong , Li Sheng‐Xian , Dong Zhi‐Qing , Feng Wei , Wang Xin‐You , Gu Shu‐Ying , Wu Yan‐Hui , Huang Xiang‐An
Published: August 2002

Several multilayer thin low‐density polyethylene (LDPE) films were fabricated by blown thin film having a thickness of 7 μm and an area of 130 cm2. They were characterized for their oxygen‐enrichment performance from air by a constant pressure–variable volume method in a round permeate cell with an effective area of 73.9 cm2. The relationship between oxygen‐enrichment properties, including oxygen‐enriched air (OEA) flux, oxygen concentration, permeability coefficients of OEA, oxygen, nitrogen, as well as separation factor through the multilayer LDPE films, and operating parameters, including transfilm pressure difference, retentate/permeate flux ratio, temperature, as well as layer number, are all discussed in detail. It is found that all of the preceding oxygen‐enrichment parameters increase continuously with an increase of transfilm pressure difference from 0.1 to 0.65 MPa, especially for the trilayer and tetralayer LDPE films. The oxygen concentration and separation factor appear to rapidly increase within the retentate/permeate flux ratio below 200, and then become unchangeable beyond that, whereas the OEA flux and the permeability coefficients of OEA, oxygen, and nitrogen seem to remain nearly constant within the whole retentate/permeate flux ratio investigated, especially for the monolayer and bilayer LDPE films. The selectivity becomes inferior, whereas the permeability becomes superior, as the operating temperature increases from 23 to 31°C. The highest oxygen concentration was found to be 44.8% for monolayer LDPE film in a single step with air containing oxygen of 20.9% as a feed gas and operating pressure of 0.5 MPa at a retentate/permeate flux ratio of 340 and 23°C. The results demonstrate a possibility to prepare an oxygen‐enriching membrane directly from air, based on the easily obtained thin LDPE films. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 83: 3013–3021, 2002; DOI 10.1002/app.2331
Establishing management schemes on marine Special Areas of Conservation in Scotland
Authors: Baxter John M.
Published: August 2002

1. The challenges and critical points in the development of a management scheme for a marine Special Area of Conservation (SAC) are discussed.

2. The need for sufficient information to justify the selection of an area and, subsequently, to inform any debate on management decisions and a monitoring programme, together with the requirement to make such information readily and widely available are highlighted.

3. The development of a management scheme should be inclusive and involve all interested parties, so that there is ultimately as wide as possible ownership of the scheme.

4. It is important that sufficient opportunity is given for all issues to be adequately investigated, discussed and resolved. A realistic but flexible timetable needs to be set at the beginning of the process with a clear understanding by all those involved that there is a definite end point to this process.

5. The importance of identifying the potential benefits of marine SACs, and not just the possible constraints, is important in achieving these overall goals. Copyright © 2001 John Wiley & Sons, Ltd.
Cuticular hydrocarbons of the ectoparasitic wasp Cephalonomia hyalinipennis (Hymenoptera: Bethylidae) and its alternative host, the stored product pest Caulophilus oryzae (Coleoptera: Curculionidae)
Authors: Howard Ralph W. , Pérez‐Lachaud Gabriela
Published: August 2002

Cuticular hydrocarbons of an ectoparasitic wasp attacking two beetle hosts have been identified and examined for the influence of age, gender, mating status, and host on hydrocarbon composition. The 37 wasp hydrocarbons identified consisted of a series of n‐alkanes (C16 to C33), 3‐, 5‐, 9‐, 10‐, 11‐, and 12‐methyl alkanes and a series of Z‐7 and Z‐9 monoenes (C23:1 to C27:1). One C25:2 diene was found. No effects of hydrocarbon composition as a function of age, gender, or mating status were found for the wasps. Wasps reared on Hypothenemus hampei, however, had 12/37 significant abundance differences to those reared on Caulophilus oryzae, although all but one of these differences were for components in less than 2% relative abundance. The C25:2 diene from wasps reared on H. hampei was present in about 10% whereas from wasps reared on C. oryzae it was present in about 2%. The hydrocarbons of one host for this wasp, the coffee berry borer (Coleoptera: Scolytidae), have been previously reported [Howard and Infante, Ann. Entomol. Soc. Am. 89:700–709 (1996)]. The hydrocarbons of the alternative host, C. oryzae (Coleoptera: Curculionidae) consists of n‐alkanes (C17 to C31), 3‐, 4‐, 5‐, 7‐, 9‐, 11‐, 12‐, 13‐, 14‐, and 15‐methyl alkanes, and a series of dimethyl alkanes of the series 3, 17‐; 5, 11‐; 5, 17‐; 7, 11‐; 7, 13‐; 13, 17‐; and 15, 19‐. No unsaturated hydrocarbons were found. No significant differences in hydrocarbon composition were found between male and female C. oryzae. Hydrocarbon patterns of four species of Cephalonomia are compared and shown to be species‐specific. The data are discussed in terms of ecological and physiological parameters. Arch. Insect Biochem. Physiol. 50:75–84, 2002. Published 2002 Wiley‐Liss, Inc.
Pharmacokinetic assessment of an oral enalapril suspension for use in children
Authors: Rippley Ronda K. , Connor John , Boyle Janet , Bradstreet Thomas E , Hand Elizabeth , Lo Man‐Wai , Murphy M. Gail
Published: August 2002

The angiotensin‐converting enzyme (ACE) inhibitor enalapril is commonly used to treat pediatric hypertension. Because some children are unable to swallow tablets or require doses less than the lowest available enalapril tablet, an enalapril suspension was developed. This study examined the relative bioavailability of enalapril suspension (10 mg) (S) compared with 10‐mg marketed VASOTEC™ tablets (T) in 16 healthy adult subjects. The geometric mean ratio (S/T) estimate of urinary recovery of free enalaprilat, the active moiety, was 0.92 (90% confidence interval (CI): 0.80, 1.07). Urinary recovery data indicate that approximately 50% of the dose was absorbed (50% recovered in urine as enalapril plus enalaprilat) with about 30% of the dose recovered as free enalaprilat for both S and T. The geometric mean ratios (S/T) of serum AUC and Cmax were 1.01 (90% CI: 0.90, 1.13) and 0.98 (90% CI: 0.83, 1.16), respectively. Suspension Tmax was slightly shorter (0.5 h) than that for tablet, but this difference is not clinically significant. Both formulations were well tolerated and there were no clinically significant adverse experiences. We conclude that the bioavailability of enalapril oral suspension 10‐mg is similar to that of VASOTEC™ 10‐mg tablet. Instructions for compounding enalapril are provided. Copyright © 2000 John Wiley & Sons, Ltd.
Effects of extremely low frequency (50 Hz) magnetic field on morphological and biochemical properties of human keratinocytes
Authors: Manni Vanessa , Lisi Antonella , Pozzi Deleana , Rieti Sabrina , Serafino Annalucia , Giuliani Livio , Grimaldi Settimio
Published: August 2002

We investigated the effects on human keratinocytes (HaCaT) of exposure to a sinusoidal magnetic field of 2 mT (50 Hz). These cells are a good model for studying interaction of nonionising radiation, because they are not shielded from fields in vivo and also because they are resistant to both mechanical and thermal stimuli. We performed scanning microscopy which showed modification in shape and morphology in exposed cells. This modification is related to differential actin distribution as revealed by phalloidin fluorescence analysis. Moreover, the exposed cells show increased clonogenic capacity, as well as increased cellular growth as showed by clonogenicity assays and growth curves. Indirect immunofluorescence analysis using a fluorescent antibody against involucrin and β4 integrin, which are respectively differentiation and adhesion markers, revealed an increase of involucrin expression and segregation of β4 integrin in the cell membrane in cells exposed to 50 Hz; a higher percentage of the exposed cells shows a modified pattern of adhesion and differentiation markers. We also present evidence that exposure of HaCaT cells can interfere with protein kinase activity. Our observations confirm the hypothesis that electromagnetic fields at 50 Hz may modify cell membrane morphology and interfere with initiation of the signal cascade pathway and cellular adhesion. Bioelectromagnetics 23:298–305, 2002. © 2002 Wiley‐Liss, Inc.
Comparison of nitrophenylethyl and hydroxyphenacyl caging groups
Authors: Du Xinlin , Frei Heinz , Kim Sung‐Hou
Published: August 2002

Nitrophenylethyl (NPE)‐ and hydroxyphenacyl (HPA)‐caged nucleotides were employed in a time‐resolved Fourier transform IR spectroscopy study on Ras‐catalyzed guanosine triphosphate (GTP) hydrolysis. A fast kinetic component was observed following the photolysis of NPE‐caged nucleotides in the NPE‐GTP‐Ras complex. However, this kinetic component was not observed in the HPA‐GTP‐Ras experiment. This fast kinetic component was likely due to a chemical reaction between Ras and the detached caging group, nitrosoacetophenone. This communication serves as a note of caution in interpreting spectral changes and kinetic behavior of the enzymatic systems employing NPE‐caged compounds. © 2001 John Wiley & Sons, Inc. Biopolymers (Biospectroscopy) 62: 147–149, 2001
Iteration model of starch hydrolysis by amylolytic enzymes
Authors: Wojciechowski Piotr M. , Koziol Antoni , Noworyta Andrzej
Published: August 2002

An elaborate computer program to simulate the process of starch hydrolysis by amylolytic enzymes was been developed. It is based on the Monte Carlo method and iteration kinetic model, which predict productive and non‐productive amylase complexes with substrates. It describes both multienzymatic and multisubstrate reactions simulating the “real” concentrations of all components versus the time of the depolymerization reaction the number of substrates, intermediate products, and final products are limited only by computer memory. In this work, it is assumed that the “proper” substrate for amylases is the glucoside linkages in starch molecules. Dynamic changes of substrate during the simulation adequately influence the increase or decrease of reaction velocity, as well as the kinetics of depolymerization. The presented kinetic model, can be adapted to describe most enzymatic degradations of a polymer. This computer program has been tested on experimental data obtained for α‐ and β‐amylases. © 2001 John Wiley & Sons, Inc. Biotechnol Bioeng 75: 530–539, 2001.
Glycogen metabolism in aerobic mixed cultures
Authors: Dircks K. , Beun J. J. , van Loosdrecht M. , Heijnen J. J. , Henze M.
Published: August 2002

In this study, the metabolism of glycogen storage and consumption in mixed cultures under aerobic conditions is described. The experimental results are used to calibrate a metabolic model, which as sole stoichiometric variables has the efficiency of oxidative phosphorylation (δ) and maintenance requirement in units of adenosine triphosphate (mATP). Using the experimental data and values from the literature we show that δ and mATP are strongly coupled and that the values determined for glycogen and poly‐β‐hydroxybutyrate (PHB) metabolism are similar. We also demonstrate that storage of glycogen and subsequent growth occur without significant loss of energy, as compared with direct growth on glucose. For kinetic modeling, Monod kinetics is used most commonly in activated sludge models to describe the rate of microbial transformation. Monod kinetics, however, does not provide a good description of the data obtained. Second‐order kinetics gives a better description of the rate of glycogen degradation. Formation and consumption of glycogen appears to be much faster than for PHB. © 2001 John Wiley & Sons, Inc. Biotechnol Bioeng 73: 85–94, 2001.
Clinical anatomy research in a research‐driven anatomy department
Authors: Jones D.G. , Dias G.J. , Mercer S. , Zhang M. , Nicholson H.D.
Published: August 2002

Clinical anatomy is too often viewed as a discipline that reiterates the wisdom of the past, characterized more by description of what is known than by active investigation and critical analysis of hypotheses and ideas. Various misconceptions follow from an acceptance of this premise: the teaching of clinical anatomists is textbook based, there is no clinical anatomy research worthy of the name, and any research that does exist fails to utilize modern technology and does not stand comparison with serious biomedical research as found in cell and molecular biology. The aim of this paper is to challenge each of these contentions by reference to ongoing clinical research studies within this department. It is argued that all teaching (including that of clinical anatomy) should be research‐informed and that the discipline of clinical anatomy should have at its base a vigorous research ethos driven by clinically related problems. In interacting with physicians, the role of the clinical anatomist should be to promulgate a questioning scientific spirit, with its willingness to test and challenge accepted anatomic dicta. Clin. Anat. 3:228–232, 2002. © 2002 Wiley‐Liss, Inc.
Transcatheter closure of patent ductus arteriosus using Gianturco coils in adolescents and adults
Authors: Wang Jou‐Kou , Liau Chau‐Song , Huang Juey‐Jen , Hsu Kwan‐Leh , Lo Ping‐Han , Hung Jui‐Song , Wu Mei‐Hwan , Lee Yuan‐Teh
Published: August 2002

We present the short‐ and intermediate‐term results of transcatheter closure of patent ductus arteriosus with Gianturco coils in adolescents and adults. During a 5‐year period, 55 patients (44 females, 11 males) with ages ranging from 14 to 72 years (median, 23) underwent attempted transcatheter closure of patent ductus with the Gianturco coils. The diameter of the narrowest segment of the ductus ranged from 0.8 to 7.6 mm (3.9 ± 1.3 mm). The 55 patients were divided into three groups. Group I consisted of nine patients with a ductal diameter ≤ 3 mm, group II consisted of 27 patients with a ductal diameter > 3 mm but ≤ 4 mm, and group III consisted of 19 patients with a ductal diameter > 4 mm. Four‐ to five‐loop Gianturco coils were used, which were deployed via retrograde aortic route. Multiple‐coil technique was generally applied in group II patients. Balloon occlusion technique in combination with multiple‐coil technique was generally used in group III patients. Deployment of coil was successful in 51 patients (93%) but failed in 4. The success rate of coil deployment in group I, II, and III were 100% (9/9), 96% (26/27), and 84% (16/19), respectively. A mean of 1.9 ± 0.7 coils was deployed per patient. Of the four patients with unsuccessful coil deployment, three underwent surgery and one received implantation with Amplatzer duct occluder. Distal embolization of 21 coils occurred in 10 patients (3 in group II and 7 in group III), from whom 20 coils were retrieved with a gooseneck snare and 1 coil was removed during surgery. The mean diameter of ductus in the 10 patients with distal embolization was significantly larger than that in those without (5.2 ± 1.4 vs. 3.7 ± 1.1 mm; P < 0.01). Among the 51 patients with successful coil deployment, immediate complete closure was achieved in 20 (39%), while trivial to mild leak was present in 31 (61%). No significant complications were encountered. After a follow‐up period ranging from 5 to 42 months, four patients had a small residual shunt and three underwent a second intervention with complete occlusion. None had left pulmonary artery stenosis documented with Doppler echocardiography. Transcatheter closure of ductus with the Gianturco coils is safe and feasible in the majority of adolescents and adults. Taking high embolization rate in patients with a ductus diameter > 4 mm into consideration, controlled‐release coils, Buttoned device, or Amplatzer duct occluder can be a better choice. Cathet Cardiovasc Intervent 2002;55:513–518. © 2002 Wiley‐Liss, Inc.
Percutaneous ulnar artery approach for coronary angiography: A preliminary report in nine patients
Authors: Terashima Masayoshi , Meguro Taiichiro , Takeda Hisanao , Endoh Norio , Ito Yuko , Mitsuoka Mikio , Ohtomo Tatsushi , Murai Osamu , Fujiwara Satomi , Honda Hidehiko , Miyazaki Yasusuke , Kuhara Ryoji , Kawashima Osamu , Isoyama Shogen
Published: August 2002

The radial artery approach is becoming more popular for diagnostic cardiac catheterization and interventional procedures because of its lower incidence of access site complications and decreased patient discomfort after the procedure. However, Allen's test reveals inadequate blood supply through the ulnar artery to the hand, and therefore the approach does not seem to be suitable in 10%–30% of patients. Here we demonstrated a new percutaneous ulnar artery approach for coronary angiography in nine patients. We succeeded in obtaining an entry site into the left ulnar artery in seven patients. The average time for cannulation and that for catheterization procedure were comparable with those of the radial approach previously reported from other laboratories. Complications such as bleeding, loss of an ulnar pulse, ulnar nerve injury, and the formation of an aneurysm or fistula were not observed in any patient. The ulnar approach may be another technique that decreases patient discomfort and risk, while preserving the radial artery as a potential coronary bypass graft for surgical myocardial revascularization. Cathet Cardiovasc Intervent 2001;53:410–414. © 2001 Wiley‐Liss, Inc.
Supramolecular chirality induction in bis(zinc porphyrin) by amino acid derivatives: Rationalization and applications of the ligand bulkiness effect
Authors: Borovkov Victor V. , Yamamoto Naoyuki , Lintuluoto Juha M. , Tanaka Takumi , Inoue Yoshihisa
Published: August 2002

The achiral syn conformer (face‐to‐face) of the ethane‐bridged bis(zinc porphyrin) (syn‐ZnD) transforms into the corresponding chiral extended anti bis‐ligated species (anti‐ZnD·L2) in the presence of enantiopure ligands (L: amino acid derivatives). The mechanism of the supramolecular chirality induction is based on chiral ligand binding to zinc porphyrins and subsequent formation of either right‐ or left‐handed screw structures in anti‐ZnD·L2. The screw structure formation arises from steric interactions between the bulkiest substituent at the asymmetric carbon of the ligand and the peripheral ethyl groups of the neighboring porphyrin ring directed towards the covalent bridge. The sign and amplitude of the induced circular dichroism (CD) are dependent on the steric bulk of the substituents at the chiral center. The greater difference in size between the chiral center's substituents gives the stronger induced CD signal. Rationalization of the ligand bulkiness effect on chirality induction by amino acid derivatives, application of this supramolecular system for the determination of ligand absolute configuration, and relative bulkiness of the substituents at the asymmetric carbon are discussed. Chirality 13:329–335, 2001. © 2001 Wiley‐Liss, Inc.
Combined intraarterial 5‐fluorouracil and subcutaneous interferon‐α therapy for advanced hepatocellular carcinoma with tumor thrombi in the major portal branches
Authors: Sakon Masato , Nagano Hiroaki , Dono Keizo , Nakamori Shoji , Umeshita Koji , Yamada Akira , Kawata Sumio , Imai Yasuharu , Iijima Shohei , Monden Morito
Published: August 2002

BACKGROUND

The prognosis of hepatocellular carcinoma (HCC) invading into the major branches of the portal vein (Vp3) is extremely poor.

METHODS

Eleven consecutive patients with HCC and Vp3 were treated with 2–6 cycles of a “basic” combination therapy consisting of continuous arterial infusion of 5‐fluorouracil (450–500 mg/day, for the initial 2 weeks) and subcutaneous injection of interferon‐α (5 million international units, 3 times/week, 4 weeks). In the first 3 patients, methotrexate (90 mg/day 1 of every week), cisplatin (10 mg/day), and leucovorin (30 mg/days 2 and 3 of every week) also were administered for the initial 2 weeks (“full” regimen).

RESULTS

In 8 (73%) of 11 patients, an objective response (complete response [CR] or partial response [PR]) was observed with marked regression of tumor and decrease in tumor markers. The use of the full regimen was associated with objective response in all patients; instead, they developed thrombocytopenia or leukopenia. In the subsequent 8 patients with basic regimen, 5 patients showed CR (2 cases) or PR (3 cases; objective response rate, 63%), and leukopenia was observed only in 1 patient.

CONCLUSIONS

Simple combination therapy with subcutaneous interferon‐α and intraarterial 5‐fluorouracil therefore is a promising treatment modality for intractable HCC with Vp3. Cancer 2002;94:435–42. © 2002 American Cancer Society.
Prognostic importance of tumor size for localized conventional (clear cell) renal cell carcinoma
Authors: Delahunt Brett , Kittelson John M. , McCredie Margaret R. E. , Reeve Anthony E. , Stewart John H. , Bilous A. Michael
Published: August 2002

BACKGROUND

The T1 and T2 classifications of the International Union Against Cancer TNM classification system for renal cell carcinoma are based on primary tumor size, and in various editions of the classification, the cut points between T1 and T2 have been amended to provide clinical utility. In the current edition, the T1/T2 cut point is less than or equal to and greater than 7 cm. and more recently a subdivision of the T1 classification (less than or equal to and < 4 cm) has been proposed to identify patients suitable for partial nephrectomy. This study investigates the prognostic significance of tumor size in a series of organ‐confined clear cell renal cell carcinomas.

METHODS

One hundred thirty cases of organ‐confined clear cell renal cell carcinomas, with a minimum of 5 years' follow‐up, were identified from the New South Wales Cancer Registry. Tumor size was compared with survival using the method of Kaplan and Meier for TNM size categories, and proportional hazards regression was used for assessing size as a continuous variable. Proportional hazards regression also was used for multivariable comparisons of size and other prognostic parameters (Fuhrman grade, AgNOR score, and Ki‐67 index) against survival.

RESULTS

Of 116 cases for which tumor dimension was recorded, 25 patients had died of cancer‐related causes. Primary tumor size ranged from 12 to 140 mm (mean, 57.3 mm). The association between survival and size was significant irrespective of the TNM classification and was also significant when size was modeled continuously (P = 0.000125, hazard of death increased by 3.51 times for each doubling of tumor size). On univariate analysis, Fuhrman grade (P = 0.04) and AgNOR score (P = 0.015) were associated with survival; however, on multivariate analysis only tumor size retained significance.

CONCLUSIONS

Although the cut point of T1 and T2 TNM categories and the proposed T1 subdivision cut point correlate with survival, our finding that size is a continuous variable indicates that as a prognostic parameter for clear cell renal cell carcinoma, primary tumor size is relative rather than indicative. Cancer 2002;94:658–64. © 2002 American Cancer Society.

DOI 10.1002/cncr.10255
Utilization of BRCA1/2 genetic testing in the clinical setting
Authors: Lee Soo‐Chin , Bernhardt Barbara A. , Helzlsouer Kathy J.
Published: August 2002

BACKGROUND

Clinical testing for BRCA1/2 has been available since 1996. Interest in testing in the research and hypothetical situations has been consistently high, but there have been limited reports on its clinical utilization.

METHODS

This is a retrospective study of BRCA1/2 test utilization by high‐risk patients who were seen at the Johns Hopkins Breast and Ovarian Surveillance Service.

RESULTS

Between February 1996 and December 1999, 258 families who had at least a 10% chance of carrying a BRCA1/2 mutation were offered genetic testing. Of these, 26 families seen between February 1996 and October 1996 had access to free testing. Overall, 68 of 258 (26%) underwent genetic testing. Educational level, number of children or daughters, breast carcinoma screening behavior, smoking and drinking behavior, perceived risk of breast carcinoma, and family history was not associated with test utilization. Eligibility for free testing, prior history of breast or ovarian carcinoma, Ashkenazi Jewish versus non‐Ashkenazi Jewish heritage, genetic risk category, and age category were associated with test utilization, and in multivariate analysis, the first three remained statistically significant factors associated with genetic testing. Only 26% of the 50 patients who did not have access to free testing sought insurance reimbursement, of which greater than 50% (7 of 13) had a prior diagnosis of breast or ovarian carcinoma.

CONCLUSIONS

The actual utilization of BRCA1/2 genetic testing in a clinical setting is lower than in the research and hypothetical settings. Potential obstacles include cost, fear of insurance discrimination, and need to involve an affected family member in the testing process. Cancer 2002;94:1876–85. © 2002 American Cancer Society.

DOI 10.1002/cncr.10420
Low incidence of BCL‐6 gene alterations for diffuse large B‐cell lymphomas in Taiwan Chinese
Authors: Chen Po‐Min , Yang Muh‐Hwa , Yu I‐Ting , Lin Jen‐Tsun , Lin Yu‐Chen , Fan Frank S. , Wang Wei‐Shu , Yen Chueh‐Chuan , Chiou Tzeon‐Jye , Liu Jin‐Hwang
Published: August 2002

BACKGROUND

In Western populations, rearrangement of the BCL‐6 gene can be identified in 20–40% of patients with diffuse large B‐cell lymphoma (DLBCL). Analysis of the BCL‐6 gene has revealed the presence of point mutations or small deletions in 70% of DLBCL tumors; however, few studies have investigated BCL‐6 gene alteration in patients with non‐Hodgkins lymphoma (NHL) of Chinese descent.

METHODS

Samples from 135 Taiwanese patients with NHL were examined (28 samples of T‐cell NHL and 107 samples of B‐cell NHL; 59 samples from patients with DLBCL) for gene rearrangement and mutation of the BCL‐6 proto‐oncogene using Southern blot analysis and single‐strand conformation polymorphism (SSCP) followed by sequence analysis.

RESULTS

BCL‐6 rearrangement and point mutations were found in 14.8% of patients (n = 20) and in 7.4% of patients (n = 10), respectively. All BCL‐6 gene alterations occurred in patients with B‐cell NHL, and none occurred in patients with T‐cell NHL. Among the 59 patients with DLBCL, BCL‐6 gene rearrangements were identified in 10 patients (16.9%), and mutations were identified in 8 patients (13.6%), with the BCL‐6 mutation occurring independent of the BCL‐6 rearrangement. The incidence of BCL‐6 gene rearrangement and mutations in patients with extranodal DLBCL was 9.5% (2 of 21 patients) and 23.8% (5 of 21 patients), respectively. Univariate analysis and multivariate logistic regression found no association between BCL‐6 gene alternations and clinical characteristics, including extranodal tumors in patients with DLBCL, and no association between the BCL‐6 alterations and prognosis was found.

CONCLUSIONS

The incidence of BCL‐6 alterations was lower in Taiwanese patients with DLBCL compared with Western populations, and BCL‐6 gene alterations showed no prognostic significance in patients with DLBCL. Cancer 2001;94:2635–44. © 2002 American Cancer Society.

DOI 10.1002/cncr.10545
Auditory and lateral line inputs to the midbrain of an aquatic anuran: Neuroanatomic studies inXenopus laevis
Authors: Edwards Christofer J. , Kelley Darcy B.
Published: August 2002

Computation of rate in auditory signals is essential to call recognition in anurans. This task is ascribed to a group of central nervous sytem nuclei in the dorsal midbrain or torus semicircularis, homologous to the inferior colliculus of mammals. We have mapped the connections of the subnuclei of the torus semicircularis inXenopus laevisto determine which receive auditory and which receive lateral line information. Relative to terrestrial anurans, the torus ofX. laevisis hypertrophied and occupies the entire caudal, dorsal midbrain. Auditory input to the torus, that arising directly from the dorsal medullary nucleus, is present only in the laminar nucleus. The principal and magnocellular nuclei receive their input from the lateral line nucleus of the medulla. All three nuclei of the torus also have reciprocal connections with the superior olive and the nucleus of the lateral lemniscus. Ascending efferents from all three nuclei of the torus innervate central and lateral thalamic nuclei, and all have a weak reciprocal connection with the posterior thalamus. The laminar and magnocellular nuclei have reciprocal connections with the ventral thalamus, and all three nuclei of the torus receive descending input from the anterior entopeduncular nucleus. The laminar and magnocellular nuclei also receive descending input from the preoptic area. Based on our identification of toral nuclei and these results we assign a major function for the detection of water‐borne sounds to the laminar nucleus and a major function for the detection of near field disturbances in water pressure to the principal and magnocellular nuclei. J. Comp. Neurol. 438:148–162, 2001. © 2001 Wiley‐Liss, Inc.
Detection and relocation of cord blood nucleated red blood cells by laser scanning cytometry
Authors: Hennerbichler Simone , Schmied Rudolf , Petek Erwin , Kroisel Peter M. , Pertl Barbara , Tiran Beate , Dohr Gottfried , Wintersteiger Reinhold , Sedlmayr Peter
Published: August 2002

Background

Fetal nucleated red blood cells (NRBC) present in the peripheral blood of pregnant women at low frequency are a potential target for noninvasive prenatal diagnostics.

Methods

CD71‐enriched cells from male cord blood (CB) were stained for the gamma chain of HbF (Hb‐γ) and cytocentrifuged. Fluorescence in situ hybridization (FISH) was done for the Y chromosome. Following staining of the nucleus with TO‐PRO‐3, laser scanning cytometry was performed. Artificial mixtures of small volumes of male CB and blood drawn from nonpregnant females were analyzed.

Results

In CB, 59% of events double positive for Hb‐γ and TO‐PRO‐3 were identified as CB‐NRBC. In contamination studies, male fetal CB‐NRBC were identified perfectly on the basis of morphologic characteristics and FISH reactivity following relocation and visual assessment. Mean recovery was 8.7%.

Conclusions

Laser scanning cytometry of preenriched fetal NRBC may offer a promising way for noninvasive prenatal diagnostics. This is because it provides a virtual enrichment step and the position on the slides of cells visually confirmed to correspond to fetal NRBC is known. Further experimental procedures on well‐defined and located target cells may be feasible. Cytometry 48:87–92, 2002. © 2002 Wiley‐Liss, Inc.
Dirofilariasis of breast: Report of two cases diagnosed by fine‐needle aspiration biopsy
Authors: Ng W.K. , Siu T.H. , Fung Berry , Kong James H.B.
Published: August 2002

We report on 2 cases of dirofilariasis of the breast occurring in adult Chinese females residing in Hong Kong. The diagnosis was made by fine‐needle aspiration biopsies. The direct smears contained numerous acute inflammatory cells, including eosinophils. A partially necrotic adult nematode of about 400–450 μm in diameter was identified in the cell‐block sections of each case. The worm was characterized by a thick cuticle with longitudinal cuticular ridges and fine transverse surface striations, abundant somatic muscle, an intestine, and a reproductive tube or uterus. The morphologic features of this round worm were most compatible with those of Dirofilaria repens. While the clinical and radiologic findings of dirofilariasis of the breast are nonspecific and mimic those of breast neoplasms or inflammatory conditions, a definitive diagnosis is possible with fine‐needle aspiration biopsy. A correct diagnosis of dirofilariasis may help to spare patients from unnecessary medical and surgical interventions. Diagn. Cytopathol. 2002;26:22–25. © 2002 Wiley‐Liss, Inc.
Hepatocellular carcinoma‐fibrolamellar variant: Cytopathology of an unusual case
Authors: Kunz George , Chung Jeffrey , Ali Syed Z.
Published: August 2002

The fibrolamellar variant of hepatocellular carcinoma (FL‐HCC) is an uncommon visceral malignancy with a distinctly better prognosis. An accurate initial diagnosis, therefore, is essential for prognostic and therapeutic reasons. This case report describes the cytomorphology of an unusual case of FL‐HCC in a 13‐yr‐old boy who was found to have a hepatic mass with prominent intraluminal growth pattern seen predominantly in the right hepatic duct. A diagnosis of FL‐HCC was originally suspected on bile duct brushings obtained during endoscopic retrograde choleangiopancreaticogram (ERCP) and subsequently confirmed on fine‐needle aspiration (FNA) and surgical resection of the hepatic tumor. The cytomorphologic profile of FL‐HCC is distinctive in the right clinical setting, allowing an accurate preoperative identification of this malignancy on biliary brushing or FNA. Diagn. Cytopathol. 2002;26:257–261. © 2002 Wiley‐Liss, Inc.
Microglial ectonucleotidases: Identification and functional roles
Authors: Braun Norbert , Zimmermann Herbert
Published: August 2002

Microglial cells represent resident macrophages of the central nervous system where they resume a resting state of unknown physiological function. They are rapidly transformed into an activated state by acute pathological events affecting the nervous system. Activated microglia function in tissue repair and regeneration but may also enhance tissue damage. Cultured microglial cells express both P2Y and P2X receptors. Activation of the microglial P2X7 receptor can result in the release of cytokines or also mediate cytotoxicity in microglial cells. Microglial cells have developed mechanisms for controlling the surrounding concentrations of free extracellular ATP via a surface‐expressed ectonucleotidase chain. We analyzed the expression of the ectonucleotidases associated with resting microglia and microglia activated by two models of cerebral ischemia. Out of a plethora of enzymes with the potential to hydrolyze extracellular nucleotides, the major ectonucleotidases associated with microglia are NTPDase1, which hydrolyzes ATP and ADP, and ecto‐5′‐nucleotidase, which catalyzes the hydrolysis of AMP to adenosine. This is shown by enzyme histochemical analysis, immunocytochemistry, Northern hybridization, and the analysis of NTPDase1‐deficient mice. Our results suggest that a major function of resting microglia could be in the lowering of interstitial levels of ATP acting either via autocrine pathways or in the ATP‐involving signaling pathways between adjacent neurons and astrocytes. Enhanced activity of NTPDase1 may protect microglia, activated by various pathological settings, from overstimulation by ATP released from the injured tissue. The parallel increase in activity of ecto‐5′‐nucleotidase would facilitate the formation of the final hydrolysis product adenosine that exerts neuromodulatory and immunomodulatory actions and contributes to the protection of neurons. Drug Dev. Res. 53:208–217, 2001. © 2001 Wiley‐Liss, Inc.
β‐phenylethylidenehydrazine, a novel inhibitor of GABA transaminase
Authors: Paslawski T. , Knaus E. , Iqbal N. , Coutts R.T. , Baker G.B.
Published: August 2002

Phenylethylidenehydrazine (PEH), a proposed metabolite of phenelzine (PLZ), was synthesized in our laboratories and administered to rats in a series of time‐ and dose–response studies. Phenelzine is a monoamine oxidase (MAO) inhibiting antidepressant/antipanic drug that also causes marked elevations of brain levels of the inhibitory neurotransmitter (γ‐aminobutyric acid (GABA). Like PLZ, PEH inhibited GABA transaminase (GABA‐T) and caused marked, long‐lasting increases in rat brain levels of GABA. The addition of the double bond in PEH caused a marked decrease in its ability to inhibit MAO compared to PLZ. Given the ability of PEH to elevate GABA levels and its lack of significant effect on MAO, it may be a very effective and safe tool with which to study the role of GABA in anxiety disorders and may be a potentially useful compound to test against seizures, ischemia, mania, and stroke. Drug Dev. Res. 54:35–39, 2001. © 2001 Wiley‐Liss, Inc.
Zebrafish yolk‐specific not really started (nrs) gene is a vertebrate homolog of the Drosophila spinster gene and is essential for embryogenesis
Authors: Young Rodrigo M. , Marty Scott , Nakano Yoshiro , Wang Han , Yamamoto Daisuke , Lin Shuo , Allende Miguel L.
Published: August 2002

By using retroviral insertional mutagenesis in zebrafish, we have identified a recessive lethal mutation in the not really started (nrs) gene. The nrs mutation disrupts a gene located in linkage group 3 that is highly homologous to the spinster gene identified in Drosophila and to spinster orthologs identified in mammals. In flies, spinster encodes a membrane protein involved in lysosomal metabolism and programmed cell death in the central nervous system and in the ovary. In nrs mutant fish embryos, we detect an opaque substance in the posterior yolk cell extension at approximately 1 day after fertilization. This material progressively accumulates and by 48 hr after fertilization fills the entire yolk. By day 3 of embryogenesis, mutant embryos are severely reduced in size compared with their wild‐type siblings and they die a few hours later. By in situ hybridization, we show that the nrs mRNA is expressed in the yolk cell at the time the mutant phenotype becomes apparent. In wild‐type embryos, nrs message is present maternally and zygotically throughout embryogenesis and is also detected in adult animals. In nrs homozygous mutant embryos, nrs transcripts are undetectable at the time the phenotype becomes apparent, indicating that the retroviral insertion has most likely abolished expression of the nrs gene. Finally, the nrs phenotype can be partially rescued by microinjection of nrs encoding DNA. These results suggest that the nrs mutation affects an essential gene encoding a putative membrane‐bound protein expressed specifically in the yolk cell during zebrafish embryogenesis. © 2002 Wiley‐Liss, Inc.
Implementation of the European Municipal Waste Incineration Directive (89/429/EEC): lessons from four member states
Authors: Schucht Simone , Bültmann Alexandra , Eames Malcolm , Lulofs Kris
Published: August 2002

Researchers and policy‐makers accept that implementation decisively influences the effectiveness of European (EU) environmental policy. Member states follow a variety of compliance (or non‐compliance) paths. Whilst in a few leading states domestic legislation tends to pre‐empt EU controls, implementation gaps and policy failures are also prevalent. What are the reasons for these differences? Why do member states follow different compliance paths? Why do implementation gaps and policy failures occur? What factors can explain the different policy outcomes achieved? What lessons can be drawn for the future? This paper addresses these questions through a comparative analysis of the implementation of the European Directive on the Reduction of Air Pollution from Existing Municipal Waste Incineration Plants (89/429/EEC) in four Member States: Germany, the Netherlands, France and the United Kingdom. Monitoring and enforcement are found to have only limited explanatory power. National contextual variables, such as public and political environmental awareness, interactions both with environmental and non‐environmental policies, regulatory anticipation and uncertainty, the degree of autonomy and scope of regulatory agencies and the industrial and market structure of the regulated industry, must also be considered. On the basis of this analysis a number of conclusions are derived for the future design of environmental policies. Copyright © 2001 John Wiley & Sons, Ltd. and ERP Environment