bluuebunny/crossref_metadata_2025 huggingface dataset:
Intravenous pyruvic acid application in minipigs partially protects acetylcholine‐esteratic but not butyrylcholine‐esteratic activity in plasma from inhibition by paraoxon
Authors: Petroianu Georg A. , Ewald Vanessa , Thyes Caroline , Missler Anke , Maleck Wolfgang H.
Published: January 2003

Intoxications with organophosphorus compounds such as paraoxon (POX) are frequent. Oximes are the only enzyme reactivators clinically available. In vitro and in vivo studies have shown that l‐lactate reduces the inhibition of plasma acetylcholine‐esteratic activity (AChEA) (in vitro and in vivo) and plasma butyrylcholine‐esteratic activity (BChEA) (at least in vitro and possibly in vivo) by POX. However, a short infusion of 10 g of lactate was unable to elevate the plasma lactate level for >3 h. In this study we tested a substance related to l‐lactate, i.e. pyruvic acid. The purpose of this animal experimental study (female minipigs with historical control group) was to determine in vivo whether intravenous (i.v.) pyruvic acid application under normoxic/normocapnic/normohydrogenaemic conditions is able to elevate blood lactate levels and whether it is able to protect AChEA and BChEA from POX inhibition.

Animals were anaesthetized, intubated and mechanically ventilated. Each received 1 mg kg−1 body wt. of POX in 50 ml of saline over 50 min and 10 g (ca. 0.5 g kg−1 body wt.) of i.v. pyruvic acid in 50 ml of saline over 50 min. They were compared with a historical control group of six animals that received only 1 mg kg−1 body wt. of POX in 50 ml of saline over 50 min. In central venous blood measurements of plasma AChEA and BChEA, the measurements were performed before (baseline), immediately after POX (50 min after start) and 110, 170, 230, 290, 530 and 1010 min after the start of infusion. A 10 g aliquot of i.v. pyruvic acid had a statistically significant protective effect in vivo on AChEA but not on BChE activity. Further study of the in vivo effects of pyruvic acid and l‐lactate after paraoxon intoxication and a formal comparison with standard oxime therapy seems warranted. Also, a combination therapy with l‐lactate and pyruvic acid in vivo should be investigated. Copyright © 2003 John Wiley & Sons, Ltd.
Oestrogenic activity of benzylparaben
Authors: Darbre P. D. , Byford J. R. , Shaw L. E. , Hall S. , Coldham N. G. , Pope G. S. , Sauer M. J.
Published: January 2003

Previous work has demonstrated that the alkyl esters of p‐hydroxybenzoic acid (parabens) possess oestrogenic activity, which increases with length of alkyl chain from methylparaben to n‐butylparaben and with branching in the alkyl chain from n‐butylparaben to isobutylparaben. This study reports on the oestrogenic activity of benzylparaben in a variety of assays in vitro and in vivo. Benzylparaben was able to displace [3H]oestradiol from cytosolic oestrogen receptor (ER) of MCF7 human breast cancer cells by 22% at 1000‐fold molar excess, by 40% at 10 000‐fold molar excess, by 57% at 100 000‐fold molar excess and by 100% at 1 000 000‐fold molar excess. It was able to increase expression of a stably transfected oestrogen responsive reporter gene (ERE‐CAT) in MCF7 cells after 24 h at 10−5M/10−4M and after 7 days at 10−6M/10−5M/10−4M. Proliferation of MCF7 cells could be increased by 10−6M/10−5M benzylparaben and this could be inhibited by 10−7M pure anti‐oestrogen ICI 182,780, indicating that growth effects were ER mediated. Further evidence for ER‐mediation was provided from the ability of benzylparaben to increase the growth of a second oestrogen‐dependent human breast cancer cell line ZR‐75‐1, but not the oestrogen‐insensitive MDA‐MB‐231 cell line. When tested in the presence of 10−10M 17β‐oestradiol, benzylparaben gave no antagonist response on the growth of either MCF7 or ZR‐75‐1 cells. Finally, benzylparaben could increase uterine weight in the immature mouse following topical application of three daily doses of 33 mg to dorsal skin. These results demonstrate that the oestrogenicity of methylparaben can be increased by the addition of an aryl group as well as by lengthening or branching the alkyl grouping. Copyright © 2003 John Wiley & Sons, Ltd.
Protective effects of erdosteine against doxorubicin‐induced cardiomyopathy in rats
Authors: Fadillioǧlu Ersin , Erdoǧan Hasan , Söǧüt Sadik , Kuku Irfan
Published: January 2003

The usefulness of doxorubicin (DXR) is limited by its cardiotoxicity. In order to improve future DXR therapy by using a new antioxidant agent, an experimental study was designed. This study was undertaken to determine whether DXR‐induced cardiotoxicity is prevented by erdosteine, a mucolytic agent showing antioxidant properties. Three groups of male Sprague‐Dawley rats (60 days old) were used: one group was untreated as a control; the other groups were treated with DXR (single i.p. dosage of 20 mg kg−1 body wt.) or DXR plus erdosteine (10 mg kg−1 day−1, orally), respectively. The DXR treatment without erdosteine increased antioxidant enzyme activities and also increased lipid peroxidation in myocardial tissue. The rats treated with DXR plus erdosteine produced a significant decrease in lipid peroxidation in comparison with control and DXR groups. Furthermore, erdosteine administration led to an increase in antioxidant enzyme activities in comparison with the control group. Erdosteine treatment also increased the activities of catalase (CAT) and glutathione peroxidase (GSH‐Px) in comparison with the DXR group. There was no significant difference in lipid peroxidation of myocardial tissue between control and DXR plus erdosteine‐treated rats. It was concluded that erdosteine caused an increase in the activities of antioxidant enzymes, especially GSH‐Px and CAT, protecting the heart tissue sufficiently from oxidative damage to membrane lipids and other cellular components induced by DXR. Copyright © 2003 John Wiley & Sons, Ltd.
In vitro protection of plasma cholinesterases by metoclopramide from inhibition by paraoxon
Authors: Petroianu G. , Kühn F. , Thyes C. , Ewald V. , Missler A.
Published: January 2003

Metoclopramide (MCP) is a dopamine receptor antagonist and serotonine receptor agonist widely used as an antiemetic and gastric prokinetic drug. In addition MCP is a reversible inhibitor of cholinesterases from human central nervous system and blood. MCP may have a cholinesterase protective effect against inhibition by organophosphates.

The purpose of the study was to quantify “in vitro” by means of the IC50‐shift the extent of MCP conferred protection, using paraoxon (POX) as an inhibitor. POX is a widely used organophospate responsible for a large number of accidental or suicidal exposures.

Cholinesteratic activities (ChE) (with acetyl‐thiocholine (A) and butyryl‐thiocholine (B) as substrates) in human plasma were measured photometrically in the presence of different POX concentrations and IC50 was calculated. Determinations were repeated in the presence of increasing MCP concentrations. It appears that the shift induced by the presence of MCP increases with the MCP concentration in a linear manner.

In the presence of a clinically easily achievable plasma concentration of 1 µM MCP the IC50 of POX for ChE ‘shifts’ by a factor of ≈2–3. The protective effect of metoclopramide on cholinesterases could be of practical relevance in the treatment of paraoxon poisoning. We conclude that in vivo testing of MCP as an organophosphate protective agent is warranted. Copyright © 2003 John Wiley & Sons, Ltd.
Constraints to expanding access to health interventions: an empirical analysis and country typology
Authors: Ranson M. Kent , Hanson Kara , Oliveira‐Cruz Valeria , Mills Anne
Published: January 2003

This paper adopts three approaches to classifying countries by level of constraint, in order to inform the choice of strategies for expanding access to health interventions in different contexts. We find substantial heterogeneity across the 84 low‐income and (all) sub‐Saharan African countries analysed. Poor sub‐Saharan African countries are the most highly constrained; Asian countries, in general, less constrained; and the two Asian giants, China and India, consistently fall above the median. Former Soviet Union countries rank low in terms of governance, but high for health systems variables. Only 10 per cent of the total population of the countries included lives in countries with the greatest constraints. The potential applications of the analysis are discussed, as are the limitations of the cross‐sectional, macro level approach. Copyright © 2003 John Wiley & Sons, Ltd.
Approaches to overcoming constraints to effective health service delivery: a review of the evidence
Authors: Oliveira‐Cruz Valeria , Hanson Kara , Mills Anne
Published: January 2003

This paper reviews the current evidence base regarding efforts to overcome constraints to effective health service delivery in low and middle‐income countries. A systematic literature review was chosen as the approach to gather and analyse existing knowledge about how to improve the ‘close‐to‐client’ health system. We focused on three levels of constraints: community and household, the health services delivery level itself, and health sector policy and strategic management. In total, 116 studies were reviewed and their main findings presented. The results should be interpreted with caution due to the considerable limitations in the existing evidence base. Copyright © 2003 John Wiley & Sons, Ltd.
Constraints to scaling‐up health related interventions: the case of Chad, Central Africa
Authors: Wyss Kaspar , Doumagoum Moto Daugla , Callewaert Bart
Published: January 2003

This analysis of constraints to scaling‐up health‐related interventions in Chad shows that emphasis has to be put on systemic approaches which address absorptive capacity, on removal of structural constraints, and on efficient and equitable production of health services. In the production of services the development of infrastructure must not exceed the development of human resources. If the millennium development goals are to be achieved, major investments in basic and in‐service training and in management skills are crucially needed. In addition, the study shows the importance of promoting health services which actively seek to fulfil community demands and those of disadvantaged groups. Copyright © 2003 John Wiley & Sons, Ltd.
Intervening to address constraints through health sector reforms in Tanzania: some gains and the unfinished business
Authors: Munishi Gaspar Kilala
Published: January 2003

This paper describes two projects designed to address health sector constraints. The Community Health Fund attempts to create a community‐owned and community‐managed prepayment scheme. Although membership growth has been disappointing, substantial funds have been mobilized and the scheme replicated in nine additional districts. The Dar Urban Health Project aimed to improve various dimensions of health service quality, and provides a model which can be replicated elsewhere. The two cases concentrated largely on relaxing constraints related to the availability of inputs, while leaving unresolved macro‐level general infrastructural and policy‐related constraints. This omission partly explains the limited gains in relaxing constraints at the input level. Copyright © 2003 John Wiley & Sons, Ltd.
Nutritional value and functional properties of a hydrocolloidal soybean and oat blend for use in Asian foods
Authors: Inglett George E , Carriere Craig J , Maneepun Saipin , Boonpunt Thanawan
Published: January 2003

A rheological study was conducted to determine the functional properties of a hydrocolloidal blend of soybean flour and oat bran, called Soytrim. Soytrim was prepared by thermomechanically processing soybean and oat products. After finding that Soytrim had similar rheological characteristics to coconut and soybean milk products, two studies were conducted to investigate its use in improving the nutritional value of some Asian foods by reducing the saturated fat content and increasing the soluble fibre content. In the first study, four Thai foods were prepared using a 60 g kg−1 Soytrim suspension to replace some of the coconut milk, with subsequent sensory, chemical and physical analysis. A 750 g kg−1 substitution of Soytrim for coconut milk in green chicken curry gave a 74.7% reduction in saturated fat content and a 142.8% increase in soluble fibre content. Total substition of Soytrim for coconut milk in fermented soybean dip gave a 96.2% reduction in saturated fat and a 10.6% increase in soluble fibre. Total substitution in mungbean conserve gave a 97.0% reduction in saturated fat and a 19.0% increase in soluble fibre. A 500 g kg−1 substitution of soytrim for coconut milk in sweetened condensed cassava paste gave a 48.7% reduction in saturated fat and 37.5% increase in soluble fibre. Sensory evaluation of these foods revealed no distinguishable changes in acceptability at the 500 g kg−1 replacement level, but unacceptability with total substitution. In the second study, more widely consumed Asian foods, soymilk and tofu, were combined with Soytrim. These foods could also be made more nutritious when combined with Soytrim at rates of substitution up to 300 g kg−1, with satisfactory acceptability at this replacement level. In all the Asian foods studied, the hydrocolloidal blend of soybean flour and oat bran could add nutritional value by reducing saturated fat and increasing soluble fibre.

© 2002 Society of Chemical Industry
Fumonisin contamination of maize hybrids visibly damaged by Sesamia
Authors: Avantaggiato Giuseppina , Quaranta Fabrizio , Desiderio Ersilio , Visconti Angelo
Published: January 2003

Sesamia nonagrioides Lefebvre (Lepidoptera: Noctuidae) is the main insect pest of maize cultivated in Mediterranean areas, causing an increase in broken plants, a reduction in yield and a decline in grain quality. An investigation of Sesamia attacks and fumonisin accumulation on 25 maize hybrids sown as a second crop after wheat has been performed under field conditions in Central Italy in 2000. The hybrids tested in this study showed different degrees of insect damage, ranging from 12 to 57% of damaged ears per hybrid. Over 50% of the tested hybrids showed strong insect damage, with more than 30% of harvested ears visibly damaged by Sesamia. Fungal contamination by Fusarium verticillioides and F proliferatum, two well‐known producers of fumonisins, was detected in both symptomless and insect‐damaged samples. Fumonisin analysis of healthy‐looking and insect‐damaged ear samples of each hybrid showed 100% incidence of positive samples, with fumonisin contents ranging from 0.01 to 20 mg kg−1 for healthy‐looking ears and from 27 ± 32 to 287 ± 221 mg kg−1 for insect‐damaged ears. Extremely high levels of fumonisins were found in ear samples visibly damaged by Sesamia, with individual values of up to 694 mg kg−1 and average values exceeding 100 mg kg−1 in more than 50% of the hybrids. A good correlation (r = 0.749) was found between fumonisin contamination and the degree of insect damage by Sesamia of the tested hybrids, calculated on the basis of percentage of ears visibly damaged by insects and with more than 5% kernel loss. This finding leads to the conclusion that insect damage by Sesamia on maize could be used as an early indicator of fumonisin contamination.

© 2002 Society of Chemical Industry
Origin and practical significance of the sticky dough factor in 1BL/1RS wheats
Authors: Barbeau W E , Schwarzlaff S S , Uriyo M G , Johnson J M , Harris C H , Griffey C A
Published: January 2003

When translocated into wheat, the short arm of the 1R chromosome of rye carries with it linked resistance genes to powdery mildew, stripe rust, leaf rust and stem rust. The translocation is also reported to increase yield potential of hard wheats. However, many doughs made from some 1BL/1RS hard wheats are unacceptable for breadmaking purposes because of excessive stickiness and mixing intolerance. 1BL/1RS wheats may be sticky because of: the inheritance of secalin proteins from rye and absence of key glutenin subunits; higher amounts and/or differences in the composition of cell wall polysaccharides, β‐glucans and pentosans; and/or the presence of a ferulic acid ester moiety residing with the water‐soluble fraction of 1BL/1RS flours. None of these hypotheses has been proven or disproven, to date, as a cause of excessive stickiness. Investigators have found that 1BL/1RS doughs are not uniformly sticky and are in some instances less sticky than non‐1BL/1RS doughs. Significant genotype–environment interactions have been reported for dough stickiness and flour quality characteristics of 1BL/1RS wheats. Investigators have generally failed to find significant differences in the breadmaking performance of 1BL/1RS and non‐1BL/1RS hard wheats despite a report that 1BL/1RS doughs break down and soften during high‐speed mixing. The 1BL/1RS translocation has been shown to reduce cookie spread of soft wheat flours but has no deleterious effects on cake volume or texture.

© 2002 Society of Chemical Industry
Antioxidant and antimicrobial activities of Polygonum cognatum Meissn extracts
Authors: Yıldırım Ali , Mavi Ahmet , Kara Ayşe Aydan
Published: January 2003

The antioxidant activities, reducing powers, 2,2‐diphenyl‐l‐picrylhydrazyl (DPPH) radical‐scavenging activities, total phenolic compound contents and antimicrobial activities of ether, ethanol and hot water extracts of Polygonum cognatum Meissn were studied in vitro. The highest antioxidant activity was found in the water extract. However, there were no statistically significant differences among 15 µg ml−1 extract‐containing samples in linoleic acid emulsion (0.02 M, pH 7.0) during 120 h of incubation (P > 0.05). The reducing power of the water extract was the highest, but its reducing power was markedly lower than that of ascorbic acid. The highest DPPH radical‐scavenging activity was found in the water extract, with 50% DPPH radical scavenging at a concentration of 100 µg ml−1 dried water extract, while at the same concentration of dried ethanol extract the value was 12%. Surprisingly, no DPPH radical‐scavenging activity was observed in the ether extract. The concentrations of phenolic compounds found were 0.48, 0.50 and 0.01 µg ml−1 gallic acid equivalent in 10 µg ml−1 water, ethanol and ether extracts respectively. The ether and ethanol extracts showed antimicrobial activity against Staphylococcus aureus and Bacillus subtilis. The water extract did not show antimicrobial activity against the studied micro‐organisms.

© 2002 Society of Chemical Industry
Oxidation of substituted benzaldehydes by quinolinium chlorochromate: A structure and solvent dependent kinetic study
Authors: Jeyanthi G. Fatima , Elango K. P.
Published: February 2003

The kinetics of oxidation of several para‐substituted benzaldehydes by quinolinium chlorochromate was studied under pseudo‐first‐order conditions in different (hydrogen bond donor and hydrogen bond acceptor) neat organic solvents. The operation of nonspecific and specific solvent–solvent–solute interactions was explored by correlating the rate data with solvent parameters through correlation analysis. Both electron‐releasing and electron‐withdrawing substituents enhanced the rate and the Hammett plot showed a break in the reactivity order indicating applicability of dual mechanism. An explanation in conformity with structure and solvent effects on reactivity has been proposed. © 2003 Wiley Periodicals, Inc. Int J Chem Kinet 35: 154–158, 2003
The demand for game day attendance in college football: an analysis of the 1997 Division 1‐A season
Authors: Price Donald I. , Sen Kabir C.
Published: January 2003

This paper develops a predictive model which includes game, team and university specific factors that are likely to influence game day demand for Division 1‐A college football. Attendance during the 1997 regular season is used as the dependent variable. Tobit estimates of two separate equations reveal that the quality of both teams, traditional rivalry and membership of specific conferences have a significant influence on demand. In addition, colleges with lower enrollments and a higher percentage of off‐campus students attract smaller crowds. The presence of a nearby professional football team also detracts from a college team's drawing power. Copyright © 2003 John Wiley & Sons, Ltd.
Explaining the profitability of foreign banks in Shanghai
Authors: Leung M.K. , Young T. , Rigby D.
Published: January 2003

This paper uses survival analysis to examine the factors determining the time taken for branches of foreign banks in Shanghai, China to make a positive rate of return after entering that market. Particular attributes of banks including the parent bank's size, early entry and the number of branches the bank has in China are found to reduce time to profitability. Market conditions in Shanghai, captured by levels of foreign direct investment and Eurodollar interest rates, are also found to have significant effects. A number of managerial implications are drawn from the analysis in light of the greater access to the Chinese banking markets following China's accession to the WTO. To ensure long‐term profitability in Shanghai, the foreign bank needs to contain costs and risks in the new markets, formulate an effective market penetration strategy, identify appropriate customer target groups, attract businesses from firms of different countries, seek early entry and undertake more fee‐income generating businesses. Copyright © 2003 John Wiley & Sons, Ltd.
A prospective study of minimally invasive techniques in pediatric surgical oncology: preliminary report
Authors: Warmann Steven , Fuchs Jörg , Jesch Nathalie K. , Schrappe Martin , Ure Benno M.
Published: January 2003

Background

Thoracoscopic and laparoscopic techniques play a major role in pediatric surgery. However, minimally invasive surgery (MIS) has not yet established itself in pediatric surgical oncology. The authors present a prospective study investigating the role of MIS in children with cancer.

Procedure

All children with abdominal or thoracic tumors requiring surgery were registered between September, 2000 and February, 2002. Decisions regarding procedures and approaches—conventional or minimally invasive—were made by the interdisciplinary team. Data on diagnoses, surgical procedures, complications, and conversion rates were registered prospectively.

Results

Seventy‐four patients received 78 operations, 21 (26.9%) of the 78 operations were minimally invasive. Seven of 16 tumor biopsies (43.8%) and 9 of 57 tumor resections (15.8%) were performed using MIS, which was also exclusively used for diagnostic interventions. Conversions to standard techniques only occurred in 5 of 9 tumor resections. No major complications were encountered in the MIS group.

Conclusions

MIS was practical in every fourth patient in our experience so far. It proved to be an excellent approach in diagnostic interventions and tumor biopsies, whereas efficacy is limited in tumor resections. Further factors (tumor recurrence, trocar site recurrence, tumor growth, and dissemination after CO2 insufflation) have to be evaluated. Our data encourage the continuation of the study. Med Pediatr Oncol 2003;40:155–157. © 2003 Wiley‐Liss, Inc.
Outcome after relapse in an unselected cohort of children and adolescents with Ewing sarcoma
Authors: Shankar A.G. , Ashley S. , Craft A.W. , Pinkerton C.R.
Published: January 2003

Background

Survival after relapse in patients with Ewing sarcoma is very poor and this retrospective study attempts to identify of prognostic factors predicting survival after relapse.

Procedure

A total of 191 patients with localised Ewing sarcoma were registered in the ET‐2 trial of the United Kingdom Children's Cancer Study Group (UKCCSG). All patients received standardised primary treatment with chemotherapy and surgery and or radiotherapy as local modality treatment. Sixty‐four patients who relapsed are included in this report. Treatment at relapse was variable and included chemotherapy, surgery, radiotherapy and high dose therapy (HDT) or megatherapy with peripheral stem cell transplantation (PBSCT) or autologous bone marrow transplantation (ABMT) in various combinations. A subgroup of patients had only non‐specific symptomatic treatment at relapse. Both univariate and multivariate methods were used to investigate variables affecting survival after relapse.

Results

The overall actuarial median survival from relapse for all patients was 14 months (95% CI 11–16 months). Univariate analysis showed that males had a longer survival (median, 16 months vs. 11 months); patients who relapsed while on treatment did worse (median, 3 months vs. 16 months) and patients who had a longer disease‐free interval (DFI) prior to relapse had a better outcome (DFI <1 year, median survival = 3 months; DFI 1–2 years, survival = 8 months; DFI > 2 years, median survival = 24 months,P < 0.001). Multivariate analysis confirmed that duration of first remission was the only factor associated with longer survival after relapse.

Conclusions

These data suggest that although aggressive therapy may delay disease progression after relapse for some children, the course of the disease after relapse is usually fatal. International co‐operative studies are needed to evaluate new strategies. Med Pediatr Oncol 2003;40:141–147. © 2003 Wiley‐Liss, Inc.
Hodgkin disease in ataxia‐telangiectasia patients with poor outcomes
Authors: Sandoval Claudio , Swift Michael
Published: January 2003

Background

To determine the presenting clinicopathologic features and treatment outcomes of 11 ataxia‐telangiectasia (A‐T) patients with Hodgkin disease.

Procedure

We reviewed the charts of 412 A‐T patients to ascertain cases of Hodgkin disease. The data analyzed included date of diagnosis, duration of symptoms, chest radiographic findings, stage and histology, therapy, and outcome.

Results

The six male and five female patients had a median age at diagnosis of 12.2 years. Eight patients presented with fever, cough, and/or cervical lymphadenopathy with a median duration of symptoms of 3 months. Five patients had abnormal chest radiographic findings a median of 3 months prior to diagnosis and were treated with antibiotics for presumed pneumonia. Mediastinal and hilar adenopathy in addition to bilateral infiltrates were present. Histopathology reports were available for nine patients. Three had nodular sclerosing and two each had lymphocyte depleted, mixed cellularity, and not otherwise specified histology. Eight patients had stage IV disease, one had stage III, and in two the staging was not documented. Six patients received reduced‐dose chemotherapy, two received radiation therapy, two did not receive therapy, and in one the treatment was not documented. In no patient did the Hodgkin disease remit and all died with a median survival of 3 months. Eight died of pneumonia and three of multiple system organ failure.

Conclusions

A‐T patients with Hodgkin disease have markedly reduced survival compared to Hodgkin disease in the general population. Their poor outcomes may be due to advanced Hodgkin disease, failure to recognize coincident chronic lung disease, and the use of non‐standard treatment regimens. Med Pediatr Oncol 2003;40:162–166. © 2003 Wiley‐Liss, Inc.
DNQ–novolac photoresists revisited: 1H and 13C NMR evidence for a novel photoreaction mechanism
Authors: Roy Debmalya , Basu P. K. , Raghunathan P. , Eswaran S. V.
Published: January 2003

Photoactive compounds, such as diazonaphthoquinone (DNQ) esters, blended with novolac resins, solvents and certain additives, serve as photoresists. These are used for printing of electronic circuits at the micron or sub‐micron level. Patterns are generated based on changes in the physical and chemical properties of the exposed and unexposed photoresist surfaces (printed circuit boards). The huge polarity change between the exposed and unexposed photoresists is exploited in the technique of microlithography. It is believed that the large polarity difference is due to acid formation in the exposed photoresist by a photochemical reaction of DNQ on exposure to light. However, it has also been suggested that in the unexposed part of a photoresist, the novolac resin undergoes an azo coupling reaction with DNQ, leading to an increase in the molecular weight of the resin, rendering it more insoluble in base. The protons in the para positions of the m‐cresol units incorporated in the novolac resin are believed to take part in this azo coupling reaction with DNQ. In this paper, we propose a novel mechanism of action of positive photoresists in the unexposed part of photoresists for dissolution inhibition using molecular modelling, 1H NMR, 13C NMR and DEPT‐135 NMR spectroscopic techniques. Our results enable us to propose that the diazo group of DNQ attacks the methylene bridges rather than the aromatic moiety of the resin. This mechanism explains the pattern formation observed using even p‐cresol‐based resins, where no free para positions are present in the aromatic ring. Copyright © 2003 John Wiley & Sons, Ltd.
Non‐empirical calculations of NMR indirect carbon–carbon coupling constants: 2. Strained polycarbocycles
Authors: Krivdin Leonid B.
Published: January 2003

High‐level non‐empirical calculations of carbon–carbon spin–spin coupling constants in a series of strained polycarbocycles have been carried out, in excellent agreement with available experimental data. The utmost importance of electronic correlation effects in this case has been demonstrated and it has been shown that the Second‐Order Polarization Propagator Approach (SOPPA) is an adequate method to account for those effects. It has been demonstrated that the most reliable basis sets to calculate J(C,C) at the SOPPA level are the correlation‐consistent basis sets of Dunning and co‐workers augmented with inner core s‐functions or decontracted in their s‐parts. The nature of the unusual bridgehead–bridgehead bonds in bicyclobutane and propellane in terms of s‐characters of bonding hybrids and also the hybridization effects in spiropentane are discussed based on the arguments derived from the current calculations of J(C,C) in the title compounds. The values of the unknown J(C,C) in propellane and spiropentane are predicted with high reliability. Copyright © 2003 John Wiley & Sons, Ltd.
19F, 13C NMR analysis of an oxygen carrier, perfluorotributylamine, and perfluoropentanoic acid
Authors: Ribeiro Anthony A. , Umayahara Keiko
Published: January 2003

NMR relaxation measurement of perfluorocarbons (PFCs), such as perfluorotributylamine (FTBA), is a convenient method for the determination of oxygen concentrations in tissues and tumors. Previous relaxation studies of FTBA used different 19F NMR assignments causing some confusion. Fluorine‐detected 19F, 13C HMQC and HMBC and selectively 19F‐decoupled 13C NMR provided unequivocal 19F and 13C assignments for FTBA and perfluoropentanoic acid (FPA). Based on those assignments, 13C spin–lattice relaxation time constants (T1) and effective correlation times for FTBA and FPA are reported and discussed. Copyright © 2003 John Wiley & Sons, Ltd.
Configurational assignment in alkyl‐branched sugars via the geminal C,H coupling constants
Authors: Schulte Jürgen , Lauterwein Jürgen , Klessinger Martin , Thiem Joachim
Published: January 2003

The measurement of the magnitude and sign of 2J(C,H) couplings offers a reliable way to determine the absolute configuration at a carbon center in a fixed cyclic system. A decrease of the dihedral angle ϕ in the O—CA—CB—H fragment always leads to a change of the 2J(CA,HB) coupling to more negative values, independent of the type and position of substituents at the two carbon centers. The orientations of the two substituents at C‐3 of the epimeric pair 1 and 2 were determined unambiguously through the measurement of the geminal coupling constants between C‐3 and the hydrogen atoms at C‐2 and C‐4. In particular, 2J(C‐3,H‐2ax) with −1.5 Hz, ϕ = 174° in 1 and −6.6 Hz, ϕ = 47° in 2, and 2J(C‐3,H‐4) with +1.5 Hz, ϕ = 175° in 1 and −4.7 Hz, ϕ = 49° in 2 showed the greatest differences between the two epimers. Both couplings therefore allow the determination of the absolute configuration at C‐3. It should be noted, however, that the size of the coupling constants can be different for dihedral angles of nearly identical size, when there are different numbers of electronegative substituents on the two coupling pathways, i.e. no O‐substituent at C‐2, but one axial O‐substituent at C‐4. It becomes clear that it is not sufficient to measure the magnitude of 2J coupling constants only, but that the sign of the geminal coupling is needed to identify the absolute configuration at a chiral center. The coupling of C‐3 with H‐2eq is not useful for the determination of the configuration at C‐3, as the similarity of the dihedral angles ϕ (O—C‐3—C‐2—H‐2eq) (57° in 1 and 70° in 2) leads to identical coupling constants (−6.1 Hz) for both epimers. Copyright © 2003 John Wiley & Sons, Ltd.
Deuterium isotope effects on 15N chemical shifts of double Schiff bases in the solid state and solution
Authors: Dziembowska T. , Ambroziak K. , Rozwadowski Z. , Schilf W. , Kamieński B.
Published: January 2003

The proton transfer equilibrium in a series of double Schiff base derivatives of trans‐1,2‐diaminocyclohexane in solution and the solid state was studied by means of 15N NMR spectroscopy and analysis of the deuterium isotope effect on the chemical shifts Δ15N(D). The presence of a proton transfer equilibrium in the N‐2‐hydroxynaphthylidene moieties of the Schiff bases studied in the solid state at room temperature was evidenced. The results confirmed the interrelation of the two hydrogen bonds in double Schiff base derivatives of trans‐1,2‐diaminocyclohexane. Copyright © 2003 John Wiley & Sons, Ltd.
Structure elucidation and 13C NMR spectral assignments of 3α‐hydroxyolean‐12‐en‐30‐oic acid, a new triterpene from Bocconia arborea
Authors: Chávez María Isabel , Julián Aníbal , Delgado Guillermo
Published: January 2003

The structure and 13C NMR assignments of 3α‐hydroxyolean‐12‐en‐30‐oic acid (20‐epi‐katonic acid), a novel pentacyclic triterpene isolated from the aerial parts of Bocconia arborea (Papaveraceae), are reported. Copyright © 2003 John Wiley & Sons, Ltd.
A new cytotoxic limonoid from Odontadenia macrantha from the Suriname rainforest
Authors: Prakash Chaturvedula V. S. , Schilling Jennifer K. , Wisse Jan H. , Miller James S. , Evans Randy , Kingston David G. I.
Published: January 2003

Bioassay‐guided fractionation of the methanol extract of Odontadenia macrantha afforded a new limonoid, odontadenin A (1) and two known triterpenoids, lupeol (2) and α‐amyrin (3). The structure of 1 was established on the basis of 1D and 2D NMR and high‐resolution fast atom bombardment mass spectrometric data. The new compound was found to possess moderate cytotoxicity against A2780, the ovarian cancer cell line. Copyright © 2003 John Wiley & Sons, Ltd.
An inverse radiation problem of simultaneous estimation of heat transfer coefficient and absorption coefficient in participating media
Authors: Park H. M. , Lee W. J.
Published: January 2003

An inverse radiation problem is investigated where the spatially varying heat transfer coefficient h(z) and the absorption coefficient κ in the radiant cooler are estimated simultaneously from temperature measurements. The inverse radiation problem is solved through the minimization of a performance function, which is expressed by the sum of square residuals between calculated and observed temperature, using the conjugate gradient method. The gradient of the performance function is evaluated by means of the improved adjoint variable method that can take care of both the function estimation and the parameter estimation efficiently. The present method is found to estimate h(z) and κ with reasonable accuracy even with noisy temperature measurements. Copyright © 2002 John Wiley & Sons, Ltd.
Application of a new differential quadrature methodology for free vibration analysis of plates
Authors: Karami G. , Malekzadeh P.
Published: January 2003

A new methodology is introduced in the differential quadrature (DQ) analysis of plate problems. The proposed approach is distinct from other DQ methods by employing the multiple boundary conditions in a different manner. For structural and plate problems, the methodology employs the displacement within the domain as the only degree of freedom, whereas along the boundaries the displacements as well as the second derivatives of the displacements with respect to the co‐ordinate variable normal to the boundary in the computational domain are considered as the degrees of freedom for the problem. Employing such a procedure would facilitate the boundary conditions to be implemented exactly and conveniently. In order to demonstrate the capability of the new methodology, all cases of free vibration analysis of rectangular isotropic plates, in which the conventional DQ methods have had some sort of difficulty to arrive at a converged or accurate solution, are carried out. Excellent convergence behaviour and accuracy in comparison with exact results and/or results obtained by other approximate methods were obtained. The analogous DQ formulation for a general rectangular plate is derived and for each individual boundary condition the general format for imposing the given conditions is devised. It must be emphasized that the computational efforts of this new methodology are not more than for the conventional differential quadrature methods. Copyright © 2002 John Wiley & Sons, Ltd.
On numerical analyses in the presence of unstable saturated porous materials
Authors: Benallal A. , Comi C.
Published: January 2003

The numerical analysis of the dynamic evolution problem concerning an elastic–plastic saturated porous media in the presence of softening (or non‐associativity) is considered in the framework of the Biot formulation extended to take into account plastic phenomena. The finite step boundary value problem, obtained by discretization in time of the continuous initial boundary value problem, is studied and the issue of its ill‐posedness is particularly addressed. The conditions for the loss of ellipticity are established for the linearized problem solved at each iteration when using the Newton–Raphson scheme. In particular, the roles of the algorithmic properties on this loss of ellipticity are derived in detail. The integration scheme of the balance of mass equation plays a major role and it is shown that the fluid flow (Darcy's law) does indeed introduce a length scale but in addition to being dependent on the integration time step, it is found to be insufficient for regularization. To illustrate and corroborate the obtained results, a one‐dimensional example (exhibiting all the features of the three‐dimensional situation) is considered and the corresponding linearized finite step problem is solved in closed form. Copyright © 2002 John Wiley & Sons, Ltd.
Expression of haem oxygenase in cirrhotic rat liver
Authors: Wei Chang‐Li , Lee Kang‐Hoe , Khoo Hoon‐Eng , Hon Wei‐Min
Published: February 2003

The haem oxygenase (HO)/carbon monoxide (CO) system has been implicated as a modulator of hepatobiliary function. This study investigated HO expression in the process of cirrhosis development, as well as its relationship to nitric oxide synthase (NOS). Liver cirrhosis was induced in rats by chronic bile duct ligation (BDL). HO mRNA expression was evaluated by competitive RT‐PCR, while protein expression was determined by immunoblotting and immunohistochemistry. In liver tissue where cirrhosis had fully developed, the expression levels of HO‐1 were greatly enhanced at both mRNA and protein level compared with sham livers. Immunohistochemistry showed that HO‐1 was induced in hepatocytes and enhanced in some of the Kupffer‐like cells in BDL livers. In contrast, there was no difference between the sham and the BDL livers for the expression levels of HO‐2. Interestingly, administration of the NOS inhibitor aminoguanidine (AG) or NG‐nitro‐L‐arginine methyl ester inhibited HO‐1 expression. To study further the role of HO‐1 in the development of liver cirrhosis, hepatocytes were isolated from the rats at different time points after BDL operation. HO‐1 was expressed in hepatocytes at high levels during the early onset of cirrhosis but dropped slightly at a later stage of cirrhosis. Zinc protoporphyrin IX (ZnPP), an HO inhibitor, blocked HO‐1 expression in hepatocytes from BDL cirrhotic rats, but enhanced the activity of inducible NOS (iNOS) in BDL hepatocytes. In conclusion, HO‐1 was induced in the hepatocytes of rats undergoing cirrhosis, suggesting that HO‐1 plays a role in the development of liver cirrhosis. Induction of HO‐1 may be mediated partially by iNOS. However, once it is induced, HO‐1 may be important in modulating iNOS activity, thus playing a protective role in liver cirrhosis. Copyright © 2003 John Wiley & Sons, Ltd.
The diagnosis of gestational diabetes in a multiethnic population: which diagnostic criteria should be used with respect to maternal outcome?
Authors: Pullen F , Grenfell A
Published: January 2003

Aim.

To determine whether the diagnosis of gestational diabetes should be based on a plasma glucose of ≥9.0 mmol/L 2 h post 75 g glucose load rather than the WHO recommended level of ≥7.8 mmol/L in terms of maternal post‐natal glucose tolerance.

Methods.

This was a retrospective study in which all women delivered between 1995 and 1999 with a 2 h blood glucose following 75 g oral glucose load of 7.8–8.9 mmol/L (group A) were compared to those with a 2 h value of 9.0–11.0 mmol/L (group B).

Results.

Groups A and B were similar in terms of age (32.5 ± 5.7 years versus 32.8 ± 4.7 years), parity (1.4 versus 1.3), gestational age (38.8 ± 1.7 weeks versus 38.5 ± 2.3 weeks) and infants born >97 percentile (6.9% versus 5.6%). The ethnic make‐up of each group was also similar; group A consisted of 11 White, 57 Asian, 25 Black and eight Mediterranean women, group B of seven White, 37 Asian, 26 Black and one Mediterranean women. Postpartum, none from group A and one (1.4%) from group B (Asian) had diabetes, eight (7.9%) from group A (three Asian, five Black) and eight (11.2%) from group B (six Asian, one Black, one White) had impaired glucose tolerance while three (2.9%) from group A (one Asian, one Black, one White) and one (1.4%) from group B (Asian) had impaired fasting glucose. Subsequent oral glucose tolerance tests in those women with impaired glucose tolerance post‐partum have shown that in group A three have reverted to normal, two have remained as impaired glucose tolerance, one has developed diabetes and two have been lost to follow‐up, while in group B two have reverted to normal, three have remained as impaired glucose tolerance and one has developed diabetes with two being lost to follow‐up. In those with impaired fasting glucose post‐natally all three women from group A have developed diabetes while the one from group B has remained normal.

Conclusions.

These results suggest that with respect to maternal post‐natal carbohydrate tolerance current WHO recommendations for the diagnosis of GDM should be used for women from ethnic minority populations. Copyright © 2002 John Wiley & Sons, Ltd.
Diabetes and driving in the UK
Authors: Durston JC
Published: January 2003

In the interest of road safety those who suffer with a medical condition likely to cause a sudden disabling event at the wheel or inability to safely control their vehicle from any other cause should not drive.

Diabetes is one of many medical conditions that may adversely affect driving ability and is therefore subject to legal requirements for the issue of a driving licence. The main concern is hypoglycaemia, especially if this is associated with impaired awareness. Other complications are also taken into account.

The secretary of State for Transport, Local Government and the Regions (DfT) has responsibility, via his medical advisors at the Drivers Medical Group at DVLA, to ensure that all licence holders are fit to drive. © Crown Copyright 2002. Reproduced with the permission of Her Majesty's Stationery Office. Published by John Wiley & Sons, Ltd.
Quadriparesis as initial presentation of hyperosmolar non‐ketotic diabetes
Authors: De P , Fergusson A , Kallarackal G , Wild S , Poolman M , Child DF
Published: January 2003

Acute onset quadriparesis can be a manifestation of a variety of neurological and metabolic conditions. We report the case of a 47‐year‐old alcoholic gentleman who presented with acute onset weakness of all four limbs associated with hypokalemia and very high blood glucose (hyperosmolar nonketotic diabetes—HNKD) detected for the first time. He was confirmed as having type 2 diabetes (detectable insulin and C‐peptide levels) and his quadriparesis completely resolved on potassium replacement and treatment with insulin. HNKD is discussed along with the possible mechanisms of hypokalemia in this patient presenting with reversible limb weakness as an initial manifestation of type 2 diabetes. Copyright © 2002 John Wiley & Sons, Ltd.
The influence of lipophilicity and formulation on the distribution of pesticides in laboratory‐scale sediment/water systems
Authors: Bromilow Richard H , Evans Avis A , Nicholls Peter H
Published: January 2003

Pesticide reaching surface waters will be sorbed by sediment. This sorption process and the influence of pesticide formulation have been examined at 10 °C in small‐scale systems having 2‐cm depth of sediment and 8‐cm overlying water stirred gently. Eight pesticides (triasulfuron, isoproturon, chlorotoluron, phenmedipham, difenoconazole, chlorpyrifos, pendimethalin and permethrin), spanning a range of physicochemical properties, were applied individually to the water. Sorption equilibrium was reached at between 15 and 30 days, the proportion of pesticide then in the sediment ranging from 20% for the acidic and therefore polar triasulfuron to 97% for the lipophilic permethrin; this behaviour was not influenced by formulation. Sorption coefficients measured in batch tests over 2 h gave good estimates of the equilibrium distribution. Some degradation was observed for all compounds over 90 days; for some compounds and formulations, enhanced degradation occurred after 20 to 60 days. It is concluded that lipophilicity is the chief determinant of pesticide distribution in sediment/water systems.

© 2003 Society of Chemical Industry
Variation in response to neonicotinoid insecticides in peach‐potato aphids, Myzus persicae (Hemiptera: Aphididae)
Authors: Foster Stephen P , Denholm Ian , Thompson Robin
Published: January 2003

Laboratory bioassays applying the neonicotinoid insecticides imidacloprid, acetamiprid and nitenpyram against clones of the peach‐potato aphid Myzus persicae (Sulzer) demonstrated that these compounds effectively circumvent the known carboxylesterase, modified acetylcholinesterase (MACE) and knock‐down (kdr) insecticide resistance mechanisms in this species. However, some clones showed cross‐tolerance (up to 18‐fold) of these compounds relative to susceptible standards. A survey assessing the frequency of neonicotinoid tolerance in M persicae in the UK, based on samples collected from the field and glasshouses between 1997 and 2000, showed that such tolerance is still rare. Experiments on neonicotinoid‐susceptible and ‐tolerant populations of M persicae under simulated field conditions in the laboratory showed that, although the latter were well controlled by imidacloprid applied at recommended application rates, they were more likely to survive and reproduce when this compound was applied at lower concentrations. Such conditions are probably periodically present in imidacloprid‐treated field and glasshouse crops. Selection favouring tolerant forms of M persicae could lead to increases in their frequency and the evolution of more potent resistance to neonicotinoids.

© 2003 Society of Chemical Industry