bluuebunny/crossref_metadata_2025 huggingface dataset:
Evaluation of infant methylenetetrahydrofolate reductase genotype, maternal vitamin use, and risk of high versus low level spina bifida defects
Authors: Volcik Kelly A. , Shaw Gary M. , Lammer Edward J. , Zhu Huiping , Finnell Richard H.
Published: March 2003

BACKGROUND

Several studies have suggested that homozygosity for the C677T 5,10‐methylenetetrahydrofolate reductase (MTHFR) variant is a potential risk factor for neural tube defects (NTDs), as individuals homozygous for the C677T allele have slightly elevated homocysteine concentrations under conditions of low folic acid intake. It has been hypothesized that maternal folic acid supplementation prevents NTDs by partially correcting reduced MTHFR activity associated with the variant form of the enzyme.

METHODS

Genomic DNA was extracted from newborn screening blood spots obtained from 145 infants with spina bifida (SB) and 260 nonmalformed control infants. The MTHFR C677T genotype was determined by restriction enzyme digestion of PCR amplification products with Hinf1. We investigated whether infant MTHFR genotype influenced the risk for the anatomic level of the SB lesion (high vs. low); we also explored whether maternal vitamin use influenced this risk.

RESULTS

Compared to controls, the frequency of SB infants with the homozygous 677 TT genotype was greatest in those infants with high level SB defects (26%; odds ratio [OR] = 2.9; 95% confidence interval [CI] = 0.9–10.1) than for those with low level SB defects (22%; OR = 1.8; 95% CI = 0.9–3.2). Furthermore, homozygous 677TT infants whose mothers did not use vitamins containing folic acid had a modestly increased risk of SB (OR = 1.8; 95% CI = 0.8–3.9), with this risk increasing more than three‐fold (OR = 5.5; 95% CI = 0.8–28.1) for those infants with high level SB defects whose mothers did not use vitamins.

CONCLUSIONS

Based upon our observations, it is suggested that the association between the infant MTHFR homozygous variant genotype and spina bifida risk may be conditional upon both lesion level and maternal vitamin use. Birth Defects Research (Part A) 67:154–157, 2003. © 2003 Wiley‐Liss, Inc.
Combination therapy with folic acid and methionine in the prevention of retinoic acid‐induced cleft palate in mice
Authors: Reynolds Paul R. , Schaalje G. Bruce , Seegmiller Robert E.
Published: March 2003

BACKGROUND

During formation of the secondary palate, clefting may result when critical developmental events are altered. The purpose of this study was to reduce the incidence of retinoic acid (RA)‐induced cleft palate (CP) in mice by the co‐administration of folic acid (FA), methionine (ME) or a combination of both.

METHODS

Four groups of time‐pregnant Swiss Webster mice were injected intraperitoneally with 50 mg/kg RA on gestational day (GD) 10. Likewise, 4.0 mg/kg FA and 187 mg/kg ME were administered on GD 8–11. The experiment included a control group (RA plus H2O) and three experimental groups, (RA plus therapeutic doses of FA, ME, or FA + ME). Necropsies were carried out on GD 18 and pups were analyzed for teratogenic effects.

RESULTS

Litters that received no therapy exhibited 100% CP with individual pups showing 76% susceptibility. Each therapy administered separately reduced the frequency of CP to approximately 6%, and the combination of FA and ME completely prevented the occurrence of RA‐induced cleft palate (0%). A second experiment was conducted in which therapy levels were decreased by 25%. Litters that did not receive therapy experienced 100% clefting and individual pups exhibited CP at 86%. These therapies administered separately did not alter significantly the frequency of cleft palate.The combined doses of FA and ME, however, lowered significantly the frequency of left palate to 46%. Decreases in limb and tail defects with FA + ME therapy were also observed in both experiments.

CONCLUSIONS

Although FA and ME, at appropriate levels, can reduce individually the frequency of RA‐induced cleft palate and other defects in mice, the results from the present study suggest that there is an additive interaction between the two therapeutic agents that can reduce further the teratogenic impact of RA. Further studies are needed to assess the mechanism of action of concomitant doses of FA and ME in the reduction of drug‐induced birth defects. Birth Defects Research (Part A) 67168–173, 2003. © 2003 Wiley‐Liss, Inc.
Embryonic and adult vasculogenesis
Authors: Drake Christopher J.
Published: March 2003

Two mechanisms account for the formation of blood vessels, vasculogenesis and angiogenesis. Unfortunately, the terms vasculogenesis and angiogenesis literally have the same meaning, i.e., the genesis of blood vessels, and thus do little to distinguish between the two processes. Despite the nomenclature, the two processes are clearly distinct. Vasculogenesis, the de novo formation of blood vessels from mesoderm, is driven by the recruitment of undifferentiated mesodermal cells to the endothelial lineage and the de novo assembly of such cells into blood vessels. Angiogenesis is the generation of new blood vessels from endothelial cells of existing blood vessels, a process driven by endothelial cell proliferation. Recent years have seen dramatic changes in our understanding of the process of vasculogenesis, expanding the scope of its occurrence beyond the earliest stages of development to include involvement in neovascular processes throughout development as well as in the adult. In this review, emphasis is placed on discussion of emerging perspectives on the process of vasculogenesis in both the embryo and the adult. Birth Defects Research (Part C) 69:73–82, 2003. © 2003 Wiley‐Liss, Inc.
X‐ray studies on ligands
Authors: Deschamps Jeffrey R. , Flippen‐Anderson Judith L. , George Clifford
Published: March 2003

Advances in x‐ray crystallographic data collection, structure solution, and refinement/validation have reduced the time required and expanded the range of samples amenable to x‐ray crystallographic studies. Consequently, we can now collect complete atomic resolution data sets on physically smaller crystals and solve larger problems by direct methods beyond what could have been accomplished even five years ago. Applying these improved methods to the study of opioid ligands has enhanced our knowledge of the opioid pharmacophore. Despite considerable progress, it is still difficult to define the pharmacophoric parameters required for highly selective and potent opioid peptides. In part this is due to the conformational flexibility remaining even in conformationally constrained peptides. © 2003 Wiley Periodicals, Inc. Biopolymers (Pept Sci) 66:287–293, 2002.
Structural models for dimerization of G‐protein coupled receptors: The opioid receptor homodimers
Authors: Filizola Marta , Weinstein Harel
Published: March 2003

Among the most exciting functional features of G‐protein coupled receptors (GPCRs) that are coming into focus lately are those relating to the role and structural characteristics of their oligomerization (mostly homo‐ and heterodimers). The structural underpinnings of these novel functional insights are still not clear, as current experimental techniques have not yet succeeded in identifying the dimerization interfaces between GPCR monomers. Two computational approaches have recently been designed in our lab to provide reasonable three‐dimensional (3D) molecular models of the transmembrane (TM) regions of GPCR dimers based on a combination of the structural information of receptor monomers and analyses of correlated mutations in receptor families. The modeling of GPCR heterodimers has been described recently. We present here a related approach for modeling of GPCR homodimers that identifies the interfaces in the most likely configurations of the complexes. The approach is illustrated for the three cloned opioid receptor subtypes (OPRD, OPRM, and OPRK). © 2002 Wiley Periodicals, Inc. Biopolymers (Pept Sci) 66:317–325, 2002
Chalcogenide‐Lewis Acid Mediated Reactions of Electron‐Deficient Alkynes with Aldehydes
Authors: Kinoshita Sayaka , Kinoshita Hironori , Iwamura Tatsunori , Watanabe Shin‐ichi , Kataoka Tadashi
Published: March 2003

Reactions of but‐3‐yn‐2‐one (2) with aldehydes 1 in the presence of a Lewis acid and dimethyl sulfide (3 a) predominantly gave (E)‐α‐(halomethylene)aldols 4–5 in high yields, while reactions of methyl propiolate (6 a) mainly afforded (Z)‐3‐halogeno‐2‐(hydroxymethyl)acrylates 7–8 in low to moderate yields. A reaction of dimethyl acetylenedicarboxylate (10) with 1 a in the presence of TiCl4 and 1,1,3,3‐tetramethylthiourea (3 c) produced maleate (E)‐11 (40 %) and butenolide 12 (40 %). When a reaction of 6 a with 1 a was carried out in the presence of TiBr4 and 3 a (0.2 equiv) at −20 °C for 60 h, 3‐(methylthio)‐2‐(hydroxyalkyl)acrylate 9 a was obtained in an 8 % yield. Experiments were conducted in order to elucidate the formation mechanism of 9 a, and it was made clear that 9 a was formed via the processes of the Michael addition of sulfide 3 a to alkynoate 6 a and an aldol reaction with 1 a and demethylation.
Can patient selection for bladder preservation be based on response to chemotherapy?
Authors: Sternberg Cora N. , Pansadoro Vito , Calabrò Fabio , Schnetzer Sylvia , Giannarelli Diana , Emiliozzi Paolo , De Paula Francesco , Scarpone Paolo , De Carli Piero , Pizzo Maurizio , Platania Andrea , Amini Mostafà
Published: March 2003

BACKGROUND

Neoadjuvant chemotherapy for patients with muscle‐invasive bladder carcinoma is given to treat micrometastases and to preserve the bladder. The objective of this study was to evaluate the possibility of bladder preservation in patients with muscle‐invasive bladder carcinoma who were treated with neoadjuvant methotrexate, vinblastine, doxorubicin, and cisplatin (M‐VAC) chemotherapy.

METHODS

One hundred four consecutive patients with T2–T4,N0,M0 transitional cell carcinoma of the bladder were treated with 3 cycles of neoadjuvant M‐VAC chemotherapy. After clinical restaging, 52 patients underwent transurethral resection of the bladder (TURB) alone, 13 patients underwent partial cystectomy, and 39 patients underwent radical cystectomy.

RESULTS

The median survival for the entire group was 7.49 years (95% confidence interval, 4.86–10.0 years). Forty‐nine patients (49%) were T0 at the time of TURB after receiving M‐VAC. Thirty‐one of 52 patients (60%) who received chemotherapy and underwent TURB alone were alive at a median follow‐up of 56 + months (range, 10–160 + months): Twenty‐three patients (44%) in that TURB group maintained an intact bladder. Of 13 responding patients with monofocal lesions who underwent partial cystectomy, only 1 patient required salvage cystectomy, and survival generally was good. The 5‐year survival rate for this group was 69%. With a long median follow‐up of 88 + months (range, 16–158 months), 4 patients (31%) were alive with a functioning bladder. In the radical cystectomy group, the median follow‐up was 45 months (range, 4–172 + months), and 15 of 39 patients (38%) patients remained alive. In 77 patients who had their tumors down‐staged to T0 or superficial disease, the median follow‐up was 63 months (range, 4–172 + months), and the 5‐year rate survival was 69%. This is in contrast to a 5‐year survival rate of only 26% in 27 patients who failed to respond and had a status ≥ T2 after receiving chemotherapy (median follow‐up, 31 months; range, 7–156 + months). The median survival for 27 elderly patients (age ≥ 70 years; median age, 73 years; range, 70–82 years) was 90 months (7.5 years). For elderly patients who underwent TURB and partial cystectomy, the 5‐year survival rate was 67% with a 109‐month (9‐year) median survival; 47% of patients preserved their bladders intact. The median follow‐up of the living elderly patients was 61 months (range, 20–120 + months).

CONCLUSIONS

Bladder sparing in selected patients on the basis of response to neoadjuvant chemotherapy is a feasible approach that should be confirmed in prospective, randomized trials. Selected elderly patients are candidates for this approach. Cancer 2003;97:1644–52. © 2003 American Cancer Society.

DOI 10.1002/cncr.11232
Stricture of the proximal esophagus in head and neck carcinoma patients after radiotherapy
Authors: Laurell Göran , Kraepelien Thomas , Mavroidis Panayiotis , Lind Bengt K. , Fernberg Jan‐Olof , Beckman Mats , Lind Magnus G.
Published: March 2003

BACKGROUND

It is well recognized that many patients with head and neck carcinoma have problems with food intake and malnutrition. The objective of the current study was to determine the clinical pattern of patients with nonneoplastic stricture of the upper esophagus after radiotherapy for head and neck carcinoma.

METHODS

A retrospective chart study of 22 patients with stricture of the proximal esophagus diagnosed between 1993 and 1999 at Karolinska Hospital was performed. The dose volume histograms of the first 2 cm and 5 cm, respectively, of the proximal esophagus were calculated.

RESULTS

Five of the patients (23%) had total obliteration. The first 2 cm of the esophagus received at least 60 grays (Gy) in > 80% of the volume. Radiation injury was not reported to occur at doses < 60 Gy. There was a correlation found between dysphagia during radiotherapy and the development of proximal esophageal stricture. Stricture was diagnosed 1–60 months (median, 6 months) after radiotherapy. In 18 patients, the stricture was treated with single or repeated endoscopic dilation. These treatments allowed a nearly normal diet in 78% of the patients.

CONCLUSIONS

Stricture of the upper esophagus is one deglutition disorder that is reported to occur after radiotherapy for head and neck carcinoma. In the current study, the authors emphasize the importance of knowing the tolerance of the normal esophagus to irradiation as well as early diagnosis of stricture of the proximal esophagus because this condition may lead to physical and emotional distress. Cancer 2003;97:1693–700. © 2003 American Cancer Society.

DOI 10.1002/cncr.11236
Spatial test filters for dynamic model large‐eddy simulation with finite elements
Authors: Tejada‐Martínez A. E. , Jansen K. E.
Published: March 2003

In this article we will develop spatial filters required in the dynamic model of small‐scale turbulent fluid motions in large‐eddy simulation with finite elements. The characterization of these finite element filters is crucial because it is seen to have an impact on incompressible Navier–Stokes simulation results. Copyright © 2003 John Wiley & Sons, Ltd.
A preconditioner freeze strategy for numerical solution of compressible flows
Authors: Silva R. S. , Almeida R. C. , Galeão A. C.
Published: March 2003

It is well known that Krylov–Schwarz methods are well suited for solving linear systems of equations in high‐latency, distributed memory environments and constitute powerful tools when combined with Newton–Krylov methods to solve Computational Fluid Dynamics problems. Nevertheless, the computational costs related to the Jacobian and the preconditioner evaluation can sometimes be prohibitive. In this work a strategy to reduce these costs is presented, based on evaluating a new preconditioner only after it had been frozen for several time steps. Numerical experiments show the computational gain achieved with the proposed strategy. Copyright © 2003 John Wiley & Sons, Ltd.
A novel boundary element method to solve free torsion problems
Authors: Songying Chen , Leqin Wang , Guijun Li
Published: March 2003

The free torsion boundary integral equation is established using the Weighted Residual Method. The divergence free property of the boundary integrand is established. Evaluation of the warp function on the boundary is transformed into numerical evaluation of warp potential functions on the boundary of the free torsion pillar, with no singular numerical integrals. Copyright © 2003 John Wiley & Sons, Ltd.
Fluorescence lifetime‐resolved pH imaging of living cells
Authors: Lin Hai‐Jui , Herman Petr , Lakowicz Joseph R.
Published: March 2003

Background

The regulation and maintenance of intracellular pH are critical to diverse metabolic functions of the living cells. Fluorescence time‐resolved techniques and instrumentations have advanced rapidly and enabled the imaging of intracellular pH based on the fluorescence lifetimes.

Methods

The frequency‐domain fluorescence lifetime imaging microscopy (FLIM) and fluorophores displaying appropriate pH‐dependent lifetime sensitivities were used to determine the temporal and spatial pH distributions in the cytosol and vesicular compartment lysosomes.

Results

We found that cytosolic pH levels are different in 3T3 fibroblasts, Chinese hamster ovary (CHO) cells, and MCF‐7 cells when using the pH probe carboxy‐SNAFL2. We also tracked the transient cytosolic pH changes in the living CHO cells after treatments with proton pump inhibitors, ion exchanger inhibitors, and weak base and acid. The intracellular lysosomal pH was determined with the acidic lifetime probes DM‐NERF dextrans, OG‐514 carboxylic acid dextrans, and LysoSensor DND‐160. Our results showed that the resting lysosomal pH value obtained from the 3T3 fibroblasts was between 4.5 and 4.9. The increase of lysosomal pH induced by the treatments with proton pump inhibitor and ionophores also were observed in our FLIM measurements.

Conclusions

Our lifetime‐based pH imaging data suggested that FLIM can measure the intracellular pH of the resting cells and follow the pH fluctuations inside the cells after environmental perturbations. To improve the z‐axis resolution to the intracellular lifetime‐resolved images, we are investigating the implementation of the pseudo‐confocal capability to our current FLIM apparatus. Cytometry Part A 52A:77–89, 2003. © 2003 Wiley‐Liss, Inc.
Obsessions and compulsions in anorexia nervosa subtypes
Authors: Halmi Katherine A. , Sunday Suzanne R. , Klump Kelly L. , Strober Michael , Leckman James F. , Fichter Manfred , Kaplan Allan , Woodside Blake , Treasure Janet , Berrettini Wade H. , Al Shabboat Mayadah , Bulik Cynthia M. , Kaye Walter H.
Published: March 2003

Objective

Obsession and compulsions in anorexia nervosa (AN) patients are often confused with the preoccupations and rituals that are characteristic of obsessive‐compulsive disorder (OCD). We examined the type and frequency of characteristic OCD obsessions and compulsions in a large sample of AN patients.

Method

In personal interviews with 324 AN patients, we assessed lifetime histories of eating disorder symptomatology and obsessive‐compulsive behaviors with valid semistructured interviews. Checklist category sums on the Yale‐Brown Obsessive Compulsive Scale were compared between AN and OCD subjects using generalized estimating equations.

Results

Lifetime obsessions and compulsions occurred in 68% of the AN restricting type and in 79.1% of the AN binge/purge type. The AN subgroups did not differ from OCD controls inr frequency of obsessions in the symmetry and somatic categories or in the compulsion categories of ordering and hoarding. In all other categories, the AN subgroups had a significantly lower frequency compared with the OCD controls.

Discussion

Some common phenotype characteristics shared by most AN and OCD patients suggest these disorders may share common brain behavioral pathways. However, the lack of complete overlap indicates they most likely have different loci of pathology within those pathways. © 2003 by Wiley Periodicals, Inc. Int J Eat Disord 33: 308–319, 2003.
Early‐onset anorexia nervosa: Is there evidence of limbic system imbalance?
Authors: Chowdhury Uttom , Gordon Isky , Lask Bryan , Watkins Beth , Watt Hilary , Christie Deborah
Published: March 2003

Objective

This study, part of a continuing effort to understand the pathophysiology of the brain in early‐onset anorexia nervosa, attempts to validate findings from an earlier study of regional cerebral blood flow and to correlate any abnormalities in blood flow with eating disorder psychopathology.

Method

Fifteen newly referred children and adolescents with a diagnosis of anorexia nervosa (AN) underwent regional cerebral blood flow (rCBF) examination using single‐photon computerized tomography (SPECT) and the Eating Disorders Examination (EDE) for children.

Results

Mean age was 14 years 11 months (SD = 1.35). Mean weight for height ratio was 82.79 % (SD = 10.66). SPECT findings showed that 11 (73%) had asymmetry (hypoperfusion) of blood flow in at least one area. Regions of the brain showing hypoperfusion included the temporal lobe (n = 9), parietal lobe (n = 5), frontal lobe (n = 3), thalamus (n = 3), and the caudate nuclei (n = 1). The median EDE subscale scores were high for all four subscales. Those patients with hypoperfusion had higher median EDE subscale scores than those without hypoperfusion, although the differences were not statistically significant.

Conclusions

Most patients in our study had abnormal rCBF, predominantly affecting the temporal lobe, confirming our previous findings. There was no association with the EDE scores. The findings support earlier suggestions of an imbalance in neural pathways or circuits, possibly within the limbic system. This hypothesis is considered within the context of current knowledge and suggestions made with regard to how it might be tested. © 2003 by Wiley Periodicals, Inc. Int J Eat Disord 33: 388–396, 2003.
The eating disorders medicine cabinet revisited: A clinician's guide to appetite suppressants and diuretics
Authors: Roerig James L. , Mitchell James E. , de Zwaan Martina , Wonderlich Stephen A. , Kamran Shehzad , Engbloom Sara , Burgard Melissa , Lancaster Kathryn
Published: March 2003

Objective

This article explores the frequencies of use of alternative medications, available products, and their potential toxicities.

Method

Survey data were gathered from 39 consecutive patients diagnosed with bulimia nervosa who were seeking treatment. A survey of area outlets (health food stores, pharmacies, grocery stores) was conducted to establish a database of available agents. Putative active ingredients were identified. MEDLINE literature searches, as well as reviews of specialized texts, were performed to identify the potential toxicities of the ingredients.

Results

Diet pill use was found in 64% of patients; 18 % reported use in the past month. The survey identified 167 products. Diuretic use was found in 31% of patients; 21% reported use in the past month. Twenty‐five diuretic products were identified.

Discussion

Alternative medicines are frequently used in the population of patients seeking treatment for bulimia nervosa. An abundance of products are available with potentially significant toxicities. © 2003 by Wiley Periodicals, Inc. Int J Eat Disord 33: 443–457, 2003.
Schema‐level cognitions in patients with binge eating disorder: A case control study
Authors: Waller Glenn
Published: March 2003

Objective

This study examined the schema‐level cognitions (core beliefs) of patients with binge eating disorder to determine whether these patients differ from those with bulimia nervosa. A case control method (matching groups for age and body mass index [BMI]) was used, to avoid the confounding factors that are found in most studies of this sort.

Method

All clinical women were recruited from a specialist eating disorder clinic. The index group consisted of 25 women with DSM‐IV diagnoses of binge eating disorder, who were compared with a clinical group of 25 women with bulimia nervosa and a group of 25 women with no eating disorder. Groups were closely matched for age and BMI. Each participant completed a well‐validated measure of core beliefs.

Results

Although the binge eating disorder group had a range of more negative core beliefs than nonclinical women, the differences between the clinical groups were much smaller. The binge eating disorder group had more negative core beliefs than the bulimia nervosa group in many areas. However, the bulimia nervosa group was distinguished by having the highest level of abandonment beliefs, and this difference may account for the difference in the presence of purging behaviors.

Conclusions

Levels of abandonment beliefs seem to be crucial in understanding the behavioral differences between these clinical groups—particularly the absence of purging behaviors. However, the relevance of these beliefs to treatment outcome and to other aspects of psychopathology remains to be established. © 2003 by Wiley Periodicals, Inc. Int J Eat Disord 33: 458–464, 2003.
Essential oils of six Gomidesia spp. from southern Brazil
Authors: Limberger Renata P. , Simões‐Pires, Cláudia A. , Sobral Marcos , Menut Chantal , Bessiere Jean‐Marie , Henriques Amélia T.
Published: March 2003

Essential oils from Gomidesia schaueriana, G. sellowiana, G. spectabilis, G. anacardiifolia, G. palustris and G. tijucensis, collected in Southern Brazil, were analysed by GC and GC–MS. Fifty‐two compounds were identiﬁed, representing 92–98% of the oil contents. All samples were rich in cyclic sesquiterpenes (about 90%), mainly those from the cadinene and germacrene cyclization pathway. The oils from G. schaueriana, G. spectabilis, G. anacardiifolia and G. palustris were quite similar, with a predominance of β‐caryophyllene, germacrene D, bicyclogermacrene, spathulenol, globulol and α‐cadinol. G. sellowiana was rich in spathulenol, followed by geranylgeraniol, and G. tijucensis was characterized by the presence of α‐ and β‐selinene. Copyright © 2003 John Wiley & Sons, Ltd.
Chemical constituents of the essential oils of Goniothalamus uvariodes King
Authors: Ahmad Fasihuddin bin , Jantan Ibrahim bin
Published: March 2003

The leaf, bark and root oils of Goniothalamus uvariodes King were investigated by capillary GC and GC–MS. The leaf oil was made up mainly of sesquiterpenoids, with β‐cubebene (15.2%) as the dominant component. The other major components were elemol (9.7%), epi‐α‐cadinol (6.2%), α‐muurolene (4.8%) and viridiﬂorol (4.8%). The bark oil was also rich in sesquiterpenoids, with β‐eudesmol (31.5%), γ‐eudesmol (16.0%), hedycaryol (13.6%), α‐eudesmol (5.6%) and (Z)‐nerolidol (5.2%) as the major constituents. However, the major group of compounds in the root oil was monoterpenoids, of which terpinen‐4‐ol (39.5%) and 1,8‐cineole (14.0%) were the main representatives. Copyright © 2003 John Wiley & Sons, Ltd.
Comparative composition of decanted and recovered essential oils of Eucalyptus citriodora Hook
Authors: Rajeswara Rao B. R. , Kaul P. N. , Syamasundar K. V. , Ramesh S.
Published: March 2003

The chemical composition of decanted (obtained directly by steam distillation of the leaves) and recovered (extracted from distillation water using hexane) essential oils of Eucalyptus citriodora were examined. The decanted oil was richer in citronellal (70.3%), citronellol (8.8%), citronellyl acetate (1.3%) and β‐caryophyllene (2.6%). The recovered oil was richer in isopulegol (53.0%), borneol (10.0%), menthol (5.3%), neral (6.9%), geraniol (1.4%) and eugenol (4.6%). Citronellal, the major constituent of the decanted oil, was absent in the recovered oil. Copyright © 2003 John Wiley & Sons, Ltd.
Essential oils of some Boswellia spp., Myrrh and Opopanax
Authors: Başer K. H. C. , Demirci B. , Dekebo Aman , Dagne Ermias
Published: March 2003

The essential oils obtained by hydrodistillation of resins of Boswellia neglecta, B. pirottae, B. rivae, Commiphora myrrha (myrrh) and C. guidottii (opopanax or scented myrrh) were analysed using GC–MS. α‐Thujene (19.2%), α‐pinene (16.7%) and terpinen‐4‐ol (12.5%) were found to be the major components in B. neglecta; limonene (14.8%) in B. rivae; trans‐verbenol (15.5%) and terpinen‐4‐ol (14.6%) in B. pirottae; (E)‐β‐ocimene (33%) in gum opopanax and furanoeudesma‐1,3‐diene (34%) in myrrh. Copyright © 2003 John Wiley & Sons, Ltd.
Syntheses and odour descriptions of cyclopropanated compounds: 4.1 modiﬁcation of aliphatic dienols
Authors: Kiyota Hiromasa , Takai Takafumi , Kuwahara Shigefumi
Published: March 2003

Several long‐chain aliphatic dienols used as commercial odourants were modiﬁed with cyclopropane rings, and their characteristics were examined. We used commercially available (2E, 4E)‐2, 4‐decadien‐1‐ol, (3Z, 6Z)‐3, 6‐nonadien‐1‐ol, and (2E, 6Z)‐2, 6‐nonadien‐1‐ol as parent compounds. Monocyclopropanation of the two double bonds in each compound resulted in a signiﬁcant increase of odour quality. However, dicyclopropanated analogues lost their original odour quality and intensity. Copyright © 2003 John Wiley & Sons, Ltd.
Chemical composition of the leaf volatile oil of Psidium guajava L. growing in Nigeria
Authors: Ogunwande Isiaka A. , Olawore Nureni O. , Adeleke Kasali A. , Ekundayo Olusegun , Koenig Wilfried A.
Published: March 2003

The composition of the volatile oil obtained from the hydrodistillation of the leaves of Psidium guajava L., growing in Nigeria, was studied by GC–MS. Forty‐two compounds, representing more than 90% of the volatile mixture, were identiﬁed. The signiﬁcant compounds were limonene (42.1%) and β‐caryophyllene (21.3%). Copyright © 2003 John Wiley & Sons, Ltd.
Analytic approximation formulae for pricing forward‐starting Asian options
Authors: Tsao Chueh‐Yung , Chang Chuang‐Chang , Lin Chung‐Gee
Published: March 2003

In this article we first identify a missing term in the Bouaziz, Briys, and Crouhy (1994) pricing formula for forward‐starting Asian options and derive the correct
one. First, illustrate in certain cases that the missing term in their pricing formula could induce large
pricing errors or unreasonable option prices. Second, we derive new analytic approximation formulae for valuing
forward‐starting Asian options by adding the second‐order term in the Taylor series. We show that
our formulae can accurately value forward‐starting Asian options with a large underlying asset's
volatility or a longer time window for the average of the underlying asset prices, whereas the pricing errors
for these options with the previously mentioned formula could be large. Third, we derive the hedge ratios for
these options and compare their properties with those of plain vanilla options. © 2003 Wiley Periodicals,
Inc. Jrl Fut Mark 23:487–516, 2003
Alloantigen gene therapy for head and neck cancer: Evaluation of animal models
Authors: Gleich Lyon L. , Li Ya‐Qin , Li Shunan , Gluckman Jack L. , Stambrook Peter J.
Published: March 2003

Background.

Human trials of alloantigen gene therapy, using the class I major histocompatibility complex (MHC) HLA‐B7, have demonstrated the potential efficacy of this treatment for head and neck cancer. Its mechanism remains unclear. An immune‐competent mouse model of MHC gene therapy to test factors potentially important to the tumor response is needed.

Methods.

Two cell lines were used, B4B8 cells that grow in Balb/c mice and SCC‐VII cells that grow in C3H mice. The mouse MHC H2‐Kb was used as the therapeutic gene, because it is an alloantigen to both mice strains. Plasmids that encode the H2‐Kb cDNA were prepared, and the cell lines were transfected. Mice were injected subcutaneously with naive cells to determine the tumor kinetics and serve as controls. Mice were injected with H2‐Kb transfected cells and tumor growth was compared with controls. Mice that did not grow tumor were rechallenged with naive cells to assess for tumor immunity. Mice were injected with transfected and naive cells admixed to determine whether the concentration of the alloantigen is important.

Results.

B4B8 tumors grew slowly, whereas SCC‐VII tumors grew rapidly. Transfection with H2‐Kb plasmid prevented or inhibited tumor growth of both the B4B8 and SCC‐VII tumors. This growth inhibition was independent of the number of cells injected. In the mice that did not grow tumor, tumor immunity was demonstrated after challenge with naive cells in both models. There was no relationship between induction of immunity and the timing of the challenge or initial cell quantity. The mice injected with a mixture of naive and transfected cells grew tumor, although growth was delayed in the B4B8 model.

Conclusions.

The results demonstrate that the two mouse models can serve as a rapid and slow growing tumor model of alloantigen gene therapy. In addition, it was noted that initial tumor cell number is not a significant factor for predicting tumor response and demonstrated that in both of these models alloantigen gene therapy results in significant antitumor immunity. © 2003 Wiley Periodicals, Inc. Head Neck 25: 274–279, 2003
Erosion models: quality of spatial predictions
Authors: Jetten Victor , Govers Gerard , Hessel Rudi
Published: March 2003

An Erratum has been published for this article in Hydrological Processes 18(3) 2004, 595. An overview is given on the predictive quality of spatially distributed runoff and erosion models. A summary is given of the results of model comparison workshops organized by the Global Change and Terrestrial Ecosystems Focus 3 programme, as well as other results obtained by individual researchers. The results concur with the generally held viewpoint in the literature that the predictive quality of distributed models is moderately good for total discharge at the outlet, and not very good for net soil loss. This is only true if extensive calibration is done: uncalibrated results are generally bad. The more simple lumped models seem to perform equally well as the more complex distributed models, although the latter produce more detailed spatially distributed results that can aid the researcher. All these results are outlet based: models are tested on lumped discharge and soil loss or on hydrographs and sedigraphs. Surprisingly few tests have been done on the comparison of simulated and modelled erosion patterns, although this may arguably be just as important in the sense of designing anti‐erosion measures and determining source and sink areas. Two studies are shown in which the spatial performance of the erosion model LISEM (Limburg soil erosion model) is analysed. It seems that: (i) the model is very sensitive to the resolution (grid cell size); (ii) the spatial pattern prediction is not very good; (iii) the performance becomes better when the results are resampled to a lower resolution and (iv) the results are improved when certain processes in the model (in this case gully incision) are restricted to so called ‘critical areas’, selected from the digital elevation model with simple rules.

The difficulties associated with calibrating and validating spatially distributed soil erosion models are, to a large extent, due to the large spatial and temporal variability of soil erosion phenomena and the uncertainty associated with the input parameter values used in models to predict these processes. They will, therefore, not be solved by constructing even more complete, and therefore more complex, models. However, the situation may be improved by using more spatial information for model calibration and validation rather than output data only and by using ‘optimal’ models, describing only the dominant processes operating in a given landscape. Copyright © 2003 John Wiley & Sons, Ltd.
Testing distributed soil erosion and sediment delivery models using 137Cs measurements
Authors: He Q. , Walling D. E.
Published: March 2003

Spatially distributed models of soil erosion and sediment delivery have been increasingly used in studies of catchment sediment dynamics in recent years. Distributed models permit both the spatial heterogeneity of catchment land use, soil properties and topography, and the spatial interaction of soil erosion and sediment transport processes to be represented and can, therefore, provide spatially distributed predictions of soil redistribution rates for complex three‐dimensional terrain. However, validation of such distributed models has been severely hampered by the lack of information on the spatial distribution of sediment mobilization and deposition within catchments, and has commonly been restricted to comparison of predicted and measured sediment outputs from catchments. The use of the fallout radionuclide 137Cs for documenting soil redistribution affords a means of assembling distributed information on medium‐term rates and patterns of soil redistribution within a catchment which can be used for model testing. The present study uses the 137Cs technique to investigate erosion and sediment delivery processes within a cultivated field in Devon, UK, and the results have been used to test four spatially distributed soil erosion and sediment delivery models, namely the widely used AGNPS and ANSWERS models, a topography‐based sediment delivery model, and a topography‐driven soil erosion model. Copyright © 2003 John Wiley & Sons, Ltd.
Delineation of erosion classes in semi‐arid southern African grasslands using vegetation indices from optical remote sensing data
Authors: Hochschild Volker , Märker Michael , Rodolfi Giuliano , Staudenrausch Helmut
Published: March 2003

As stated by many authors in the recent past, soil erosion is one of the major environmental problems in southern Africa and it will become even more severe in the future due to population growth and potential climatic changes. This study concerns the detection of different land degradation stages in semi‐arid grassland areas in the upper Mbuluzi‐river catchment (Kingdom of Swaziland). It has been carried out within the framework of an interdisciplinary EU‐funded project aimed at developing an integrated water resources management system (IWRMS) for water resources analyses and prognostic scenario planning in semi‐arid catchments of Southern Africa (Flügel et al., 2001 URL: http://www.iwrms.uni‐jena.de/download/Eu‐reports/report_final.pdf). Within this more general framework, particular attention was focused on the determination of high‐resolution morphometric parameters for detailed erosion process studies, as well as on the derivation of relationships between vegetation cover and bare soil. The latter has subsequently been used to delineate the vegetation cover density and C‐factor values for erosion models such as the revised universal soil loss equation. The examples from Southern Africa show that the methods applied are able to identify areas affected by different types of erosion. Furthermore, it is possible to estimate the parameters for a subsequent erosion modelling. Copyright © 2003 John Wiley & Sons, Ltd.
Integrating geographical information systems, remote sensing, ground truthing and modelling approaches for regional erosion classification of semi‐arid catchments in South Africa
Authors: Flügel Wolfgang‐Albert , Märker Michael , Moretti Sandro , Rodolfi Giuliano , Sidrochuk Aleksey
Published: March 2003

Water resources management is an important issue in southern African countries. With respect to water quality problems, the understanding of the dynamics of integrated soil erosion processes in river basins is of crucial importance. This study is on the delineation of response units (RUs) in the Mkomazi River catchment (KwaZulu/Natal; South Africa). It was carried out within the framework of an interdisciplinary EU‐funded project aimed at developing an integrated water resources management system for water resources analyses and prognostic scenario planning in semi‐arid catchments of southern Africa. Within this more general framework, particular attention was focused on the identification of sediment source areas. For this purpose, the RUs concept was applied to delineate erosion RUs (ERUs). The ERUs were subsequently used to identify heterogeneously distributed areas within a river catchment characterized by specific hydrological and erosion dynamics and features. Therefore, they can be applied as modelling entities in physically based hydrological and erosion models. Spatially distributed input data from the catchment were derived by remote sensing techniques and geographical information systems analyses. Taking into account the high amount of sediments produced by gully erosion, not considered in USLE‐type models, special attention was focused on gully erosion using a dynamic gully erosion model. The example from southern Africa shows that the methods applied are able to identify areas affected by gully erosion. Furthermore, it was possible to estimate the entire amount of soil loss, including gully erosion. Copyright © 2003 John Wiley & Sons, Ltd.
Simulation of event‐based and long‐term spatial redistribution of Chernobyl‐derived radiocaesium within catchments using geographical information system embedded models
Authors: van der Perk Marcel , Slávik Ondrej
Published: March 2003

The Chernobyl accident contaminated vast areas of Europe with radiocaesium (137Cs) in 1986. To evaluate long‐term and event‐based redistribution of Chernobyl‐derived 137Cs at the catchment scale, two geographical information system embedded models have been developed. The first model simulates 137Cs redistribution using a monthly time step based on a long‐term soil erosion model. The second model simulates lateral radiocaesium transport at the event scale based on the existing Limburg soil erosion model. This model accounts for surface runoff, soil erosion and deposition, and radiocaesium exchange between the topsoil layer, runoff water, and suspended sediment. Both models have been tested and applied to the Mochovce catchment, western Slovakia. The spatial distribution of 137Cs activity in soil simulated by the long‐term model was used as input for the event‐based model to assess the changes in 137Cs transport during rainfall events between 1986 and 2002. Soil erosion events in the first months after initial fallout input before ploughing caused a considerable decline in the 137Cs soil inventories, which were estimated at 8·9% of the total initial inventory. The majority of 137Cs transport during rainfall events occurs in particulate form. Both the absolute amounts of particulate 137Cs transport and the fraction of particulate 137Cs transport were shown to be positively related to suspended sediment transport. Between 1986 and 2002, dissolved 137Cs transport has declined by a factor of about 26, which can be largely attributed to the increased sorption to sediment particles. Particulate 137Cs transport has declined by a factor of about two, which can be largely attributed to the decrease in soil 137Cs. The 137Cs inventories in soil have decreased by a factor between three and four at the steep hillslopes, but have remained at about the same level as the initial fallout input at the valley bottoms. Copyright © 2003 John Wiley & Sons, Ltd.
Quantification of erosion patterns in the Brahmaputra–Jamuna River using geographical information system and remote sensing techniques
Authors: Khan Nasreen Islam , Islam Aminul
Published: March 2003

There is significant evidence of frequent and rapid erosion and fast rates of bank line retreat along the river Brahmaputra–Jamuna within Bangladesh. This study is aimed at quantifying the actual rates of bank erosion along the river based on time series analysis of satellite images and historical maps. Analysis shows that the erosion rates in the Brahmaputra–Jamuna River were 160 m year−1 between 1973 and 1992, indicating the severity of erosion hazard along the river. This study also revealed the fact that the river has migrated westwards at an average movement rate of 50 m year−1 during the period of 1830–1992. In 1830, the river had an average width of 6·2 km, but by 1992 the average width had increased to 10·6 km. The channel has widened at an average rate of 27 m year−1 during 1830–1914. After that, it has widened at an average rate of 65 m year−1. The average width of the river has increased about 130 m year−1 since 1973. Analysis of the Landsat images shows that, over the whole river, riverine islands most often persist from 1 to 7 years, but 30% have lasted for 14 years or more. Accretion has taken place in the middle and lower reaches north of the east bank and in the extreme north of the west bank between 1973 and 1992. The rate of accretion is not comparable with the rate of bank erosion of the Brahmaputra–Jamuna River. Copyright © 2003 John Wiley & Sons, Ltd.
A test of three soil erosion models incorporated into a geographical information system
Authors: Svorin Josefine
Published: March 2003

An examination is carried out of the application of three soil erosion models, USLE/RUSLE, SLEMSA and the Morgan, Morgan and Finney method, to the Simeto catchment in Sicily, and of the differences in the results using the three models. The models are incorporated into a grid‐based geographical information system, and the results are validated qualitatively and quantitatively. The significance of the choice of method to estimate the distributed input parameters and the method to validate the quality of the models are discussed. Copyright © 2003 John Wiley & Sons, Ltd.
Investigating reservoir sediment and watershed erosion using a geographical information system
Authors: Chang Tiao J. , Bayes Travis D. , McKeever Scott
Published: March 2003

Most economic developments may have been at the expense of soil conservation. Soil erosion results in impacts on reservoir sediment, crop yield, and water quality. This study introduces the procedure of using a geographical information system for investigating reservoir sediments and soil erosion of the corresponding watershed. First, the bathymetric surface of a reservoir is surveyed using two real‐time kinematic global position systems and a sonar‐based depth gauge. Using the on‐board computer, receivers, and sonar, bathymetric readings are recorded three times a second to establish actual coordinates and depth measurements. Data are then converted using a digital terrain model to obtain the current image bathymetric surface. The image of original bathymetric surfaces when constructed can be obtained by digitizing the existing map. The subtraction of these two images is used to estimate the amount of sediment deposits. Next, parameters of rainfall‐runoff erosivity factor, soil erodibility factor, slope length factor, slope steepness factor, cover‐management factor, and support practice factor are evaluated for each grid of the corresponding watershed. The average annual soil loss from each grid is estimated by the revised universal soil loss equation to obtain the total amount of the soil loss for the watershed. Using the example of Charles Mill Lake, Ohio, USA, the estimated average amount of sediment deposits in the lake was about 2·44 × 104 m3 year−1. On the other hand, the estimated soil erosion from the corresponding watershed was about 4·22 × 108 kg year−1 or 1·56 × 105 m3 year−1. Hence, it can be concluded that about 15·6% of the soils eroded from the watershed have been deposited in the lake. Copyright © 2003 John Wiley & Sons, Ltd.
Application of an optimization technique to a physically based erosion model
Authors: Santos Celso A. G. , Srinivasan Vajapeyam S. , Suzuki Koichi , Watanabe Masahiro
Published: March 2003

The difficulties involved in calibration of physically based erosion models have been partly attributable to the lack of robust optimization tools. This paper presents the essential concepts and application to optimize channel and plane parameters in an erosion model, with a global optimization method known as the SCE‐UA (Duan et al., 1992. Water Resources Research 28(4): 1015–1031), which has recently shown promise as an effective and efficient optimization method for calibrating watershed models. It is based on the simplex method, and in order to improve its efficiency by making the simplex expand in a direction of more favourable conditions, or contract if a move was taken in a direction of less favourable conditions, new evolution steps have been introduced. The physically based erosion model that was chosen is called WESP (watershed erosion simulation program), developed by Lopes and Lane (1988. In Sediment Budgets, Bordas MP, Walling DE (eds). IAHS Publication no. 174. IAHS: Wallingford). The optimization technique was tested with the field data collected in an experimental watershed located in a semi‐arid region of Brazil. On the basis of these results, the recommended erosion parameter values for a semi‐arid region are given, which could serve as an initial estimate for other similar areas. Copyright © 2003 John Wiley & Sons, Ltd.