bluuebunny/crossref_metadata_2025 huggingface dataset:
Cancer‐specific worry interference in women attending a breast and ovarian cancer risk evaluation program: impact on emotional distress and health functioning
Authors: Trask Peter C. , Paterson Amber G. , Wang Catharine , Hayasaka Satoru , Milliron Kara J. , Blumberg Laurie R. , Gonzalez Richard , Murray Susan , Merajver Sofia D.
Published: August 2002

Intrusive thoughts about cancer, often identified as ‘cancer‐specific worries’ or ‘cancer‐specific distress’, have been postulated to be associated with dysfunction in women at increased risk of developing breast or ovarian cancer. The current study discusses the development and validation of a measure designed to assess women's perceptions of the interference such worries create in their daily functioning. Analyses revealed that approximately two‐thirds of a high‐risk breast cancer clinic sample perceived worries about breast cancer as interfering with their functioning across a variety of life domains. Multiple regression analyses indicated that worry interference scores predicted Profile of Mood States (POMS) Anxiety and Confusion, and Short Form‐36 (SF‐36) Role‐Emotional and Mental Health scores after the effects of other variables such as frequency of worry about breast cancer, and having a family history of cancer had been considered. Women who perceived their worries as interfering with their functioning reported higher levels of anxiety and confusion, and diminished mental health and role functioning. The results add to the expanding area of anxiety/distress in at‐risk populations by providing (1) a direct measure of the perceived interference associated with breast cancer‐specific thoughts, (2) a validation of the measure via its associations with standard measures of emotional distress and health functioning, and (3) evidence of the measure's incremental predictive value in explaining distress and quality of life, after consideration of background variables, such as having a family history of cancer. Copyright © 2001 John Wiley & Sons, Ltd.
Psychosocial adjustment in children of mothers with breast cancer
Authors: Hoke Lizbeth A.
Published: August 2002

Thirty‐five children of 28 mothers diagnosed with breast cancer during the previous year were compared to 34 children of 24 mothers with recent benign breast biopsies. Mothers and children, ages 8–16, completed questionnaires about mood, behavior problems and social functioning to assess whether children of mothers with breast cancer were at increased risk for adjustment problems. Significant differences were not found between children in the breast cancer group and the comparison group on any of the measures, even though mothers with breast cancer reported more psychological distress than mothers with benign biopsies. In addition, children in both groups were functioning better than normative samples on some adjustment measures. Variables measuring the mother's illness and treatment were not significantly related to children's adjustment in the breast cancer group. Findings suggested that some adolescents whose mothers had breast cancer did better in social and academic activities when their mothers were more distressed, while adolescents whose mothers had benign biopsies did less well when their mothers were distressed. The study's small sample size limits conclusions that can be drawn; however, clinical and research implications are discussed, given other reports that some children of parents with cancer may experience adjustment problems. Copyright © 2001 John Wiley & Sons, Ltd.
Health status and life satisfaction among breast cancer survivor peer support volunteers
Authors: Alex Matthews B. , Baker Frank , Hann Danette M. , Denniston Maxine , Smith Tenbroeck G.
Published: August 2002

Two measures of health‐related quality of life (HRQOL), the Medical Outcomes Survey Short Form 36 (SF‐36) and the Satisfaction with Life Domains Scale for Cancer (SLDS‐C), were compared to examine the relationship between health status and life satisfaction among breast cancer survivors (BCSs). A total of 586 BCSs, all of whom were volunteers in peer support programs, met inclusion criteria and completed the self‐report measures. Significant correlation coefficients were shown between life satisfaction and measures of health status. SF‐36 scores were significantly higher for physical functioning, emotional well‐being, and vitality subscales compared to population norms. BCSs expressed greatest dissatisfaction with their sexual ability, physical strength, and bodies in general. Small age differences were found. Results suggest that incorporating multiple measures of HRQOL contribute to the understanding and measurement of the effects of cancer on perceived health status and life satisfaction. Copyright © 2002 John Wiley & Sons, Ltd.
Successful treatment of methicillin‐resistant Staphylococcus aureus pulmonary infection with linezolid in a patient with cystic fibrosis
Authors: Ferrin Marianne , Zuckerman Jonathan B. , Meagher Alison , Blumberg Emily A.
Published: August 2002

Methicillin‐resistant Staphylococcus aureus (MRSA) is a significant cause of pulmonary infection in patients with cystic fibrosis (CF). Because these organisms are frequently multidrug‐resistant, most patients require intravenous therapy with vancomycin. We report on the first case of successful treatment of a pulmonary exacerbation due to MRSA in a CF patient with a new antimicrobial, linezolid. We demonstrated equivalence of intravenous and oral dosing in this patient, suggesting that oral linezolid may be an excellent alternative to intravenous vancomycin for CF patients infected with MRSA. Pediatr Pulmonol. 2002; 33:221–223. © 2002 Wiley‐Liss, Inc.
Mucociliary clearance in cystic fibrosis
Authors: Robinson Michael , Bye Peter T.B.
Published: August 2002

Abnormal mucociliary clearance (MCC) is one of the central hypotheses for the development of lung disease in patients with cystic fibrosis (CF). However, attempts to demonstrate this decrease of MCC in vivo have proved to be somewhat less definitive, with the evidence barely favoring impaired clearance. Any apparent disparities are most likely due to the variety of methodologies used by different laboratories to measure MCC. The limitations of the various methodologies are examined in this review, in an attempt to better facilitate comparison of results. A number of physical and pharmacological therapies have been developed to promote mucus clearance from the CF airway. A summary of the results of interventional studies utilizing the measurement of MCC as an outcome measure is presented. Pediatr Pulmonol. 2002; 33:293‐306. © 2002 Wiley‐Liss, Inc.
Polyamines in prostatic epithelial cells and adenocarcinoma; the effects of androgen blockade
Authors: Cohen Ronald J. , Fujiwara Kunio , Holland John W. , McNeal John E.
Published: August 2002

Background

Recent identification of eosinophilic prostatic secretory granules (PSG) as the major secretory mechanism of the prostate gland and their loss in neoplasia has prompted scrutiny of their chemical constituents. Polyamines, in particular spermine and spermidine (sp/spd) are the major cations found within prostatic secretions, yet their secretory mechanism in normal and neoplastic tissues has not been investigated.

Methods

Normal prostatic tissues and adenocarcinoma from intact and chemically castrated men were preserved in a glutaraldehyde‐based fixative (Solufix®). Immunostains for sp/spd were performed before and after harsh acid hydrolysis whereby all protein was removed from tissue sections.

Results

Sp/spd immunoreactivity correlated with PSG as recognized in routine stains in tissues from intact patients before and after acid digestion. Decrease in sp/spd in untreated carcinomas was directly related to loss of PSG. After chemical castration, normal glands were mostly devoid of sp/spd while surviving malignant cells stained positively, despite a significant reduction or absence of PSG. Similarly, cancers progressing after castration were intensely decorated with anti‐spermine, despite an almost complete loss of PSG. Cytoplasmic sp/spd staining of these androgen resistant clones was in contrast to normal glands no longer acid resistant.

Conclusions

The intense eosinophilia of PSG is attributable to polyamines. Androgen blockade arrests sp/spd production in normal tissue. In contrast, sp/spd production continues in androgen resistant tumor clones, thereby uncoupling polyamines from their normal androgen dependent environment. Prostate 49:278–284, 2001. © 2001 Wiley‐Liss, Inc.
Prostatic tumor cell plasticity involves cooperative interactions of distinct phenotypic subpopulations: Role in vasculogenic mimicry
Authors: Sharma Navesh , Seftor Richard E.B. , Seftor Elisabeth A. , Gruman Lynn M. , Heidger Paul M. , Cohen Michael B. , Lubaroff David M. , Hendrix Mary J.C.
Published: August 2002

BACKGROUND

Tumor cell plasticity represents a significant clinical challenge in that the fate and function of tumor cells can be elusive until a tumor mass is evident. A remarkable example of plasticity is tumor cell vasculogenic mimicry, recently described in aggressive uveal and cutaneous melanoma, in addition to ovarian carcinoma, whereby tumor cells express endothelial‐associated genes and form de novo vasculogenic‐like networks in three‐dimensional (3‐D) culture. In the current investigation, we examined whether there is evidence for vasculogenic mimicry in heterogeneous prostatic neoplasms.

METHODS

Dunning rat and human prostate cancer cell lines (comprised of epithelial‐ and fibroblastic‐like tumor subpopulations) were tested for their ability to express selected endothelial‐associated genes, laminin, the α6β1 laminin‐binding integrin, and for their potential to form perfusable tubular networks in 3‐D culture. Simultaneous morphological analysis of tumor‐lined channels in rat and human tumors was also performed.

RESULTS

Green fluorescent protein labeling of prostatic clonal subpopulations revealed unique cooperative interactions of epithelial‐ and fibroblastic‐like tumor cells in the formation of perfusable vasculogenic‐like networks. Furthermore, while these cell lines were shown to express various vascular markers, prostatic tumor cell‐lined channels were also detected in vivo in high grade tumors, and occurred in some cases in close proximity to conventional endothelial‐lined vasculature.

CONCLUSIONS

A multidisciplinary approach to assess vasculogenic mimicry by prostatic tumor cells has revealed supportive evidence that it occurs in invasive, heterogeneous prostate cancer cell lines, and circumstantially in aggressive rat and human tumors. These results reflect the plasticity of aggressive prostatic tumor cells and may provide new prognostic markers for clinical diagnosis and new therapeutic intervention strategies. Prostate 50: 189–201, 2002. © 2002 Wiley‐Liss, Inc.
Growth inhibition of prostate cancer xenografts by halofuginone*†
Authors: Gavish Zohar , Pinthus Jehonathan H. , Barak Vivian , Ramon Jacob , Nagler Arnon , Eshhar Zelig , Pines Mark
Published: August 2002

BACKGROUND

Halofuginone, an inhibitor of collagen type I synthesis, is an anti‐angiogenic agent. Here we evaluated the efficacy of halofuginone to inhibit prostate cancer (PC) xenografts representing various phenotypes of the disease.

METHODS

An androgen‐dependent (CWR22), an androgen‐independent (PC3), and a neuroendocrine (WISH‐PC2) PC xenograft were used. Halofuginone was given orally or injected intraperitoneally. Tumor size, collagen α1(I) gene expression (in situ hybridization), collagen content (sirius red staining), angiogenesis (immunohistochemistry with factor VIII antibodies), and apoptosis/necrosis (DNA fragmentation) were evaluated.

RESULTS

Halofuginone inhibited the growth of all subcutaneously implanted xenografts and of WISH‐PC2 when transplanted orthotopically. The effect was dose‐dependent (WISH‐PC2) and accompanied by decrease in plasma PSA levels (CWR22). In all xenografts, halofuginone inhibited collagen α1(I) gene expression, reduced collagen content, and endothelial cell number resulting in an increase in apoptosis/necrotsis.

CONCLUSIONS

Oral administration of halofuginone slowed the progression of PC xenografts representing a broad range of phenotypes. Halofuginone may become a new modality for PC prevention. Prostate 51: 73–83, 2002. © 2002 Wiley‐Liss, Inc.
Ecto‐diadenosine polyphosphates hydrolase activity on human prostasomes
Authors: Minelli Alba , Allegrucci Cinzia , Liguori Lavinia , Ronquist Gunnar
Published: August 2002

BACKGROUND

Ecto‐diadenosine polyphosphates are ubiquitous compounds with several physiological roles. Ecto‐diadenosine polyphosphates hydrolase control their actions by degrading and terminating their signaling. The present work deals with the identification and partial characterization of ecto‐diadenosine polyphosphates hydrolase on human prostasomes.

METHODS

Reverse‐phase and paired‐ion HPLC techniques have been used.

RESULTS

Prostasomes have an ecto‐diadenosine polyphosphates hydrolase that leads to the degradation of several diadenosine compounds. Kinetic parameters of the enzyme show that diadenosine tetraphosphate is the preferred substrate that is further metabolized by the prostasome‐ecto‐nucleotidases to adenosine. The ecto‐enzyme is bound to the prostasome‐membranes through a GPI‐anchor and is activated by physiological concentration of Ca+2, Mg+2, and Mn+2. Its optimum pH is also in the slightly alkaline physiological range. Human spermatozoa do not possess this hydrolytic activity, but they can acquire it after fusion with prostasomes.

CONCLUSIONS

The existence of an enzyme capable of degrading diadenosine compounds and can be transferred to human spermatozoa suggests new physiological implications for the role of prostasomes in fertilization. Prostate 51: 1–9, 2002. © 2002 Wiley‐Liss, Inc.
Confirmation of the prostate cancer susceptibility locus HPCX in a set of 104 German prostate cancer families
Authors: Bochum Sylvia , Paiss Thomas , Vogel Walther , Herkommer Kathleen , Hautmann Richard , Haeussler Juergen
Published: August 2002

BACKGROUND

Several prostate cancer (PCa) susceptibility loci have been reported, but attempts to confirm them in independent data sets have produced inconsistent results. It is not yet clear, how much of this variation is due to differences between different populations. HPCX was originally identified in a combined data set of PCa families from the USA and Scandinavia. Considerable differences in the frequency of linked families were observed in this heterogeneous family sample as well as in following studies.

METHODS

In order to estimate the significance of HPCX in the German population, DNA samples from 104 PCa families were genotyped at six polymorphic markers spanning a region of approximately 14 cM on Xq27‐28, which includes the proposed HPCX candidate locus.

RESULTS

In the entire data set, a maximum NPL Z score of 1.20 (P = 0.11) at marker DXS984 was observed. Statistically significant evidence for linkage was obtained in the subset of 63 families with early‐onset disease (i.e., ≤ 65 years) with a maximum NPL Z score of 2.32 (P = 0.009) at the same location.

CONCLUSION

Our results confirm the existence of a prostate cancer susceptibility gene on Xq27‐28 also in the German population. Prostate 52: 12–19, 2002. © 2002 Wiley‐Liss, Inc.
Loss of heterozygosity at 13q14 and 13q21 in high grade, high stage prostate cancer
Authors: Dong Jin‐Tang , Boyd James C. , Frierson Henry F.
Published: August 2002

Background

Loss of heterozygosity (LOH) at chromosome 13q has been frequently detected in prostate cancer, and three regions (i.e., 13q14, 13q21, and 13q33) may harbor tumor suppressor genes important in this neoplasm. In this study, we examined the frequency of 13q LOH in advanced prostate cancers, in order to determine the clinicopathologic relevance of 13q LOH.

Methods

LOH was determined by analyzing microsatellite markers in 41 cases of microdissected predominantly high grade prostate cancer tissues and their matched nonneoplastic cells. The results were compared with those generated previously for lower grade, asymptomatic cancers.

Results

The frequencies of LOH at 13q14, 13q21, and 13q33 were 62% (21/34), 57% (20/35), and 34% (11/32), respectively. In comparison to previous results, LOH at 13q14 and 13q21 but not 13q33 was more frequent in prostate cancers that produced local clinical symptoms (bladder outlet obstruction) than those that did not (P < 0.05). LOH at 13q14 was also significantly more frequent in high grade and high stage cancers than those that were lower grade and lower stage (P < 0.05).

Conclusions

Although the target genes on 13q have not been identified in carcinomas of the prostate, LOH at 13q14 in particular is associated with clinically significant prostate cancers. Further fine mapping of these loci may lead to identification of tumor suppressor genes that are deleted in aggressive carcinomas of the prostate. Prostate 49:166–171, 2001. © 2001 Wiley‐Liss, Inc.
The effect of the herbicide glyphosate on non‐target spiders: Part I. Direct effects on Lepthyphantes tenuis under laboratory conditions
Authors: Haughton Alison J , Bell James R , Wilcox Andrew , Boatman Nigel D
Published: August 2002

We examined the toxic effects of glyphosate to adult female Lepthyphantes tenuis (Araneae, Linyphiidae), a common spider of agricultural habitats. The overspray technique was used to investigate the effect of the herbicide on forty individuals in each of six glyphosate treatments (2160, 1440, 1080, 720, 360 and 180 g ha−1) and a distilled water control. Spiders collected from the wild were individually placed in exposure chambers and checked every 24 h over a 72‐h experimental period. Mortality of L tenuis remained at less than 10% in all treatments at 24 and 48 h after spray application, and only increased marginally (to 13%) after 72 h. These results support other limited data which suggest that glyphosate is ‘harmless’ to non‐target arthropods. More extended laboratory testing to investigate any side‐effects of glyphosate on the life history of L tenuis and other non‐beneficial invertebrates is required.

© 2001 Society of Chemical Industry
The effect of the herbicide glyphosate on non‐target spiders: Part II. Indirect effects on Lepthyphantes tenuis in field margins
Authors: Haughton Alison J , Bell James R , Boatman Nigel D , Wilcox Andrew
Published: August 2002

We have examined the indirect effect of the herbicide glyphosate on the spider Lepthyphantes tenuis in field margins. Glyphosate was applied to a randomised block design field experiment comprising 360, 720 and 1440 g glyphosate AE ha−1 treatments and an unsprayed control. Spiders were sampled in each month from June to October 1998. Spider abundance was significantly lower in all the treatments than in the unsprayed control. Abundance was also significantly lower in the 720 and 1440 g treatments than in the 360 g treatment. No significant difference could be detected between the 720 and 1440 g treatments. Poisson regression models showed that patterns of decline in L tenuis were related to increasing dead vegetation and decreasing vegetation height. Glyphosate applications only had a within‐season indirect habitat effect on L tenuis as field margins sprayed 16 months after an application of 360 g glyphosate ha−1 showed no detrimental effect.

© 2001 Society of Chemical Industry
Synthesis and antigenic properties of reduced peptide bond analogues of an immunodominant epitope of the melanoma MART‐1 protein
Authors: Quesnel Anne , Zerbib Anne , Connan Francine , Guillet Jean‐Gérard , Briand Jean‐Paul , Choppin Jeannine
Published: August 2002

Backbone modifications have been introduced into the melanoma derived peptide MART‐1(27‐35) to increase its binding to class I major histocompatibility complex HLA‐A2 molecule, and ultimately to enhance its immunogenicity. Each analogue was obtained by replacing one peptide bond at a time in the natural epitope by the aminomethylene (CH2‐NH) surrogate. All analogues displayed an increased resistance to proteolysis. Interestingly, the comparative results showed that five analogues bound more efficiently to HLA‐A2 than the parent peptide. On the other hand, two pseudopeptide/HLA‐A2 complexes were recognized by one melanoma‐specific T cell clone. Close examination of the impact of such modifications at the molecular level provides useful supports for the rational design of stable compounds with applications in anti‐tumour specific immunotherapy and in vaccine development. Copyright © 2001 European Peptide Society and John Wiley & Sons, Ltd.
Central nervous system stimulatory action from the root extract of Plumbago zeylanica in rats
Authors: Bopaiah C. P. , Pradhan N.
Published: August 2002

The effects of a 50% ethanol extract of the root of Plumbago zeylanica (P. zeylanica) were investigated on locomotor behaviour and central dopaminergic activity in rats. The effects on the ambulatory behaviour were assessed along with the levels of dopamine (DA) and its metabolite homovanillic acid (HVA) in the striatum after a single oral dose (100, 200 and 300 mg/kg body weight) of the extract. The extract significantly increased the spontaneous motility in animals. The ambulatory and rotatory behaviour in the treated groups were higher than in the control group (p < 0.05). There were marked differences in the ambulatory behaviour between 100 and 300 mg/kg, indicating that the responses were stimulatory and dose‐dependent. The stereotypic behaviour which is characteristic of a dopamine agonist showed biphasic effects. However, there was no significant difference between the groups (p > 0.05). The results showed that the extract of the root of P. zeylanica specifically enhanced the spontaneous ambulatory activity without inducing stereotypic behaviour. The neurochemical estimations revealed elevated levels of DA and HVA in striatum compared with the control rats (p < 0.01). The levels were higher for the 100 mg/kg treated group than the other groups. The levels declined by increasing the dosage of the extract to 200 mg/kg and 300 mg/kg, however, these levels remained higher than the control group. The relationship between motor activity and levels of dopamine are not parallel. These behavioural and biochemical results indicated stimulatory properties of the extract of the root of P. zeylanica, which may be mediated by dopaminergic mechanisms in the rat brain. Copyright © 2001 John Wiley & Sons, Ltd.
Trigonella foenum graecum (fenugreek) seed extract as an antineoplastic agent
Authors: Sur P. , Das M. , Gomes A. , Vedasiromoni J. R. , Sahu N. P. , Banerjee S. , Sharma R. M. , Ganguly D. K.
Published: August 2002

The antineoplastic effect of Trigonella foenum graecum seed extract has been evaluated in the Ehrlich ascites carcinoma (EAC) model in Balb‐C mice. Intra‐peritoneal administration of the alcohol extract of the seed both before and after inoculation of EAC cell in mice produced more than 70% inhibition of tumour cell growth with respect to the control. Treatment with the extract was found to enhance both the peritoneal exudate cell and macrophage cell counts. The extract also produced a significant antiinflammatory effect. We report here the antiinflammatory and antineoplastic effects, of Trigonella foenum graecum seed extract. Copyright © 2001 John Wiley & Sons, Ltd.
Protective effect of Acorus calamus against acrylamide induced neurotoxicity
Authors: Shukla Pradeep K. , Khanna Vinay K. , Ali M. M. , Maurya R. R. , Handa S. S. , Srimal R. C.
Published: August 2002

Exposure of rats to acrylamide (ACR) caused hind limb paralysis in 58% of the animals on day 10 and decreased behavioural parameters, namely distance travelled, ambulatory time, stereotypic time and basal stereotypic movements compared with the control group. These rats also had a decrease in the reduced glutathione (GSH) content and glutathione‐S‐transferase (GST) activity in the corpus striatum and an increase in striatal dopamine receptors, as evident by an increase in the binding of 3H‐spiperone to striatal membranes. Treatment with the ethanol:water (1:1) extract of the rhizomes of Acorus calamus (AC‐002) increased the GSH content and GST activity in the corpus striatum while insignificant changes were observed in other parameters. Rats treated with ACR and AC‐002 in combination had a lower incidence of paralysis (18%) compared with those treated with ACR alone on day 10 of the experiment. The rats also showed a partial recovery in other behavioural parameters. The levels of GSH content and GST activity increased in the corpus striatum, while the dopamine receptors decreased compared with the ACR treated rats. The results suggest that the neurobehavioural changes produced by ACR may be prevented following treatment with Acorus calamus rhizomes. Copyright © 2002 John Wiley & Sons, Ltd.
Screening of Chinese and Mongolian herbal drugs for anti‐human immunodeficiency virus type 1 (HIV‐1) activity
Authors: Ma Chao‐mei , Nakamura Norio , Miyashiro Hirotsugu , Hattori Masao , Komatsu Katsuko , Kawahata Takuya , Otake Toru
Published: August 2002

Water and methanol extracts of 30 Chinese and Mongolian medicinal plants were tested for their human immunodeficiency virus type‐1 (HIV‐1) inhibitory activity. Of the 60 extracts, 23 showed anti‐HIV ac‐tivity. Bioassay‐guided fractionation of one of the most active extracts, the methanol extract of the root tuber of Stephania cepharantha, led to the isolation of two alkaloids, aromoline and FK‐3000 as potent inhibitory substances. They completely inhibited the cytopathic effects of HIV‐1 on MT‐4 cells at 31.3 and 7.8 μg/mL, respectively. Copyright © 2002 John Wiley & Sons, Ltd.
Möbius aromaticity in small [n] trans‐annulenes?
Authors: Havenith Remco W. A. , van Lenthe Joop H. , Jenneskens Leonardus W.
Published: August 2002

It is shown that the approximations for the derivation of the Hückel–Möbius rules used in (semi‐)empirical studies cannot be maintained at the ab initio level of theory. As the orbital degeneracy, obtained using the Hückel approximations, is not maintained at the ab initio level, the [4n+2] and [4n] Hückel–Möbius rules do not apply exactly. The existence of possible Möbius character for cis, cis, trans‐cyclohexatriene (trans‐benzene, 2) and cis, cis, cis, trans‐cyclooctatetraene (trans‐4) is investigated; their structural and magnetic properties show that both compounds possess neither antiaromatic nor aromatic properties, respectively. The lack of cyclic π‐electron conjugation is due to the reduced overlap between the pπ‐orbitals. This is demonstrated for trans‐4 in which the trans double bond is forced into the geometry of that of the cyclononatetraenyl cation (6). In that case, trans‐4 possesses aromatic properties (NICS −12.9 ppm). © 2001 John Wiley & Sons, Inc. Int J Quantum Chem 85: 52–60, 2001
Structural elucidation of disinfection by‐products in treated drinking water
Authors: Taguchi Vince Y.
Published: August 2002

Two unusual disinfection by‐products have been detected periodically in the gas chromatography/mass spectrometry (GC/MS) characterization analyses of semi‐volatile organics in treated drinking water. The electron ionization (EI) mass spectra contained mono‐chlorinated and mono‐brominated ions at m/z 107/109 and 151/153, respectively. Library searching techniques suggested mono‐halogenated butanol structures but no matches could be found. Positive ion chemical ionization (CI) spectra contained mono‐chlorinated and mono‐brominated ions at m/z 105/107 and 149/151, respectively. No [M + H]+ ions were initially observed. Accurate mass measurements confirmed the empirical formulae for the significant ions in the EI spectra and the mono‐halogenated butanol structures. Further CI experiments with other reagent gases and instruments revealed possible molecular weights of 139 and 183 Da, respectively. Tandem mass spectrometry (MS/MS) experiments in EI and CI were used to elucidate the fragmentation schemes. The two compounds have been tentatively identified as 1‐aminoxy‐1‐chlorobutan‐2‐ol and 1‐aminoxy‐1‐bromobutan‐2‐ol, respectively. Copyright © 2001 John Wiley & Sons, Ltd.
The pathogenesis of influenza in humans
Authors: Zambon Maria C.
Published: August 2002

The rapid evolution of influenza A and B viruses contributes to annual influenza epidemics in humans. In addition, pandemics of influenza are also caused by influenza A viruses, whereas influenza B does not have the potential to cause pandemics because there is no animal reservoir of the virus. Study of the genetic differences between influenza A and influenza B viruses, which are restricted to humans, may be informative in understanding the factors that govern mammalian adaptation of influenza A viruses.

Aquatic birds provide the natural reservoir for influenza A viruses, but in general, avian influenza is asymptomatic in feral birds. Occasionally, however, highly pathogenic strains of influenza cause serious systemic infections in domestic poultry. The pathogenicity of these strains is related to the presence of a polybasic cleavage sequence in the precursor of the surface glycoprotein haemagglutinin, which makes the glycoprotein susceptible to activation by ubiquitous proteases such as furin and PC6.

However, the mechanism of pathogenicity may differ in highly pathogenic strains of human influenza, such as the H1N1 pandemic strain of 1918 and the H5N1 strain involved in the outbreak in Hong Kong in 1997. Binding of host proteases by the viral neuraminidase to assist activation of the haemagglutinin, shortening of the neuraminidase and substitutions in the polymerase gene, PB2, have all been suggested as alternative molecular correlates of pathogenicity of human influenza viruses. Additionally, systemic spread in humans of pathogenic subtypes has not been demonstrated and host factors such as interferons may be crucial in preventing the spread of the virus outside the respiratory tract. Copyright © 2001 John Wiley & Sons, Ltd.
Taiwan's environment, resource sustainability and green consumerism: perceptions of university students
Authors: Wong Koon Kwai
Published: August 2002

It is argued that university students are the future elite members and decision‐makers of a society, therefore the attitudes and behaviour of Taiwanese students will have a significant effect upon the future course of development of Taiwan. This article discusses university students' perceptions of the environment, resource sustainability, and green consumerism in Taiwan. A total of 345 students studying at the National Taiwan University completed the survey questionnaire in October 1996. It is encouraging to find that most students appear to be concerned with, and aware of, the environmental and resource sustainability issues of Taiwan. Furthermore, the paper reveals students' attitude toward priority of development options, their consumption patterns and their participation in environmental protection campaigns. Students advocate a fundamental change of the prevalent wasteful lifestyle to achieve the long‐term sustainability of Taiwan. Copyright © 2001 John Wiley & Sons, Ltd and ERP Environment
Electron inelastic mean free path for Ti, TiC, TiN and TiO2 as determined by quantitative reflection electron energy‐loss spectroscopy
Authors: Fuentes G. G. , Elizalde E. , Yubero F. , Sanz J. M.
Published: August 2002

Electron inelastic mean free paths (IMFP) have been estimated for Ti, TiC, TiN and TiO2 for energies between 250 and 2000 eV. The IMFP values have been derived from the respective energy‐loss function (i.e. Im{−1/ϵ}) on the basis of the model developed by Yubero and Tougaard for quantitative analysis using reflection electron energy‐loss spectra (REELS). The IMFPs have been analysed in terms of the Bethe equation for inelastic scattering and compared with the values predicted by the TPP‐2M equation. We have distinguished between λREELS(E0) and λ∞(E0), whereby the first takes into account surface effects as they appear in REELS experiments and λ∞(E0) is the value that is approached when the surface is ignored. The IMFPs determined here are observed to decrease in the order Ti > TiN ∼ TiC > TiO2 as the density of valence electrons contributing to inelastic scattering processes increases. Furthermore, we observe a general good agreement with those values predicted by the TPP‐2M formulae, except for TiO2 for which differences of up to 30–40% have been observed. Copyright © 2002 John Wiley & Sons, Ltd.
Evaluating the safety of medicines, with particular reference to contraception
Authors: Skegg David C. G.
Published: August 2002

Toxicological studies and clinical trials cannot be expected to predict all important adverse effects of medicines and contraceptives. Post‐marketing surveillance is essentially an epidemiological task that involves detecting associations between drugs and events. The first alerts about drug safety problems have often come from case reports, but epidemiological studies are needed to confirm adverse (or beneficial) effects and to provide quantitative information. This article illustrates methodological principles by considering three examples from the field of contraceptive safety: oral contraceptives and breast cancer, intrauterine contraception and pelvic inflammatory disease, and newer oral contraceptives and venous thromboembolism. Key issues that emerge include bias and confounding, the place of subgroup analyses, random error, and the use of computerized databases. In research on contraceptive and drug safety, conclusions usually need to be based on careful assessment of multiple observational studies. Copyright © 2001 John Wiley & Sons, Ltd.
Zero‐inflated models for regression analysis of count data: a study of growth and development
Authors: Cheung Yin Bin
Published: August 2002

Poisson regression is widely used in medical studies, and can be extended to negative binomial regression to allow for heterogeneity. When there is an excess number of zero counts, a useful approach is to used a mixture model with a proportion P of subjects not at risk, and a proportion of 1‐P at‐risk subjects who take on outcome values following a Poisson or negative binomial distribution. Covariate effects can be incorporated into both components of the models. In child assessment, fine motor development is often measured by test items that involve a process of imitation and a process of fine motor exercise. One such developmental milestone is ‘building a tower of cubes’. This study analyses the impact of foetal growth and postnatal somatic growth on this milestone, operationalized as the number of cubes and measured around the age of 22 months. It is shown that the two aspects of early growth may have different implications for imitation and fine motor dexterity. The usual approach of recording and analysing the milestone as a binary outcome, such as whether the child can build a tower of three cubes, may leave out important information. Copyright © 2002 John Wiley & Sons, Ltd.
Collection of standardized information on infant feeding in the context of mother‐to‐child transmission of HIV
Authors: Gaillard Philippe , Piwoz Ellen , Farley Tim M. M.
Published: August 2002

Complete avoidance of breast‐feeding is the surest way to avoid mother‐to‐child transmission (MTCT) of HIV through breast‐feeding, but replacement feeding exposes infants, especially those born in developing countries, to the risk of other infectious diseases with consequent increase in morbidity and mortality. One study has suggested that exclusive breast‐feeding during the first months of life carries a lower risk of HIV transmission than when other foods are given in addition to breast milk. Other studies have provided limited data on the risks of HIV transmission according to different patterns of breast‐feeding, but studies have used different definitions of breast‐feeding patterns and have analysed their data with adjustment on different risk factors. This hampers our ability to understand the mechanisms underlying HIV transmission through breast milk and the risks associated with different infant feeding practices. Consequently it is difficult to determine the best interventions to reduce the risk of transmission and the development of optimal policies. In collaboration with research teams involved with infant feeding research, the World Health Organization has developed a tool to assist studies on MTCTto collect information in a standardized manner, using common definitions and terms. The purpose is to facilitate comparisons between studies and the quantification of the risks of transmission according to various feeding patterns, after adjusting for potential confounding variables. The tool includes a core questionnaire to record infant feeding practices and other key information on the mother's and the infant's health. It also provides guidance on methods of analysis and presentation of the complex data on infant feeding. The tool can be used in prospective research studies on MTCT prevention, as well as providing the framework to assess infant feeding patterns in intervention programmes, such as those providing intensive counselling to mothers on infant feeding. The tool will facilitate the compilation of information from these studies which will ultimately provide scientific basis for updating guidelines and policies on infant feeding by mothers infected with HIV. Copyright © 2001 John Wiley & Sons, Ltd.
Current and future challenges in the design and analysis of cluster randomization trials
Authors: Klar Neil , Donner Allan
Published: August 2002

Randomized trials in which the unit of randomization is a community, worksite, school or family are becoming widely used in the evaluation of life‐style interventions for the prevention of disease. The increasing interest in adopting a cluster randomization design is being matched by rapid methodological developments. In this paper we describe several of these developments. Brief mention is also made of issues related to economic analysis and to the planning and conduct of meta‐analyses for cluster randomization trials. Recommendations for reporting are also discussed. Copyright © 2001 John Wiley & Sons, Ltd.
Independent data monitoring committees: rationale, operations and controversies
Authors: Ellenberg Susan S.
Published: August 2002

Data monitoring committees (DMCs) have become an increasingly common component of randomized clinical trials in recent years. As experience has accumulated, and more individuals and organizations have become involved in such activities, a variety of approaches to the operation of such committees has inevitably arisen. Because these committees play such a critical role in the process of new drug development, it is important to consider the implications of the different approaches that are being used. It is also timely to consider the present and possible future regulatory status of data monitoring committees. Published in 2001 by John Wiley & Sons, Ltd.
Paradigm shifts in clinical trials enabled by information technology
Authors: Marks Ronald G. , Conlon Michael , Ruberg Stephen J.
Published: August 2002

The use of the world wide web for clinical trials changes the processes of performing clinical research in several fundamental ways. Greatly improved security, monitoring capability, and accuracy and timeliness of study conduct can be achieved while lowering cost. Data quality is enhanced while co‐ordinating centre effort is reduced. The web provides a natural environment for linking the various components of clinical research, leading to new levels of simplicity and efficiency. It also enhances opportunities for recruitment of study investigators and patients. Other information technology tools and databases can be used to assist in this regard as well. Web‐based trials change the relationship of the investigator site to the study and the site to the co‐ordinating centre. Different roles and responsibilities lead to simplified processes and more and higher quality data. Many standard co‐ordinating centre activities, such as randomization, protocol implementation and amending, document tracking, adverse event reporting, site monitoring, report generation and data analysis are all fundamentally changed in a web‐based trial. Opportunities are enhanced to identify potential investigators and support their successful study conduct. As the role of investigator sites is changed in web‐based research, more primary care medical providers can be attracted to research, providing more typical patients to studies than those sometimes available through more traditional research sites, especially those at academic study sites. Other activities can now be co‐ordinated electronically with the advent of the web. The Institutional Review Board (IRB) can use online tools to control investigator participation, resulting in improved study efficiency and patient safety. A web‐based research pharmacy provides tremendous efficiencies in managing and distributing study medications. Financial payments to the sites can be performed and recorded electronically, or even administered based on timeliness and quality of the data. Our early experience with web‐based trials indicates that there can be tremendous gains in study efficiency and accuracy by restructuring processes, roles and responsibilities through a comprehensive centralized, web‐based trial. The future appears bright for web‐based clinical trials. Copyright © 2001 John Wiley & Sons, Ltd.
Imputation of missing values in the case of a multiple item instrument measuring alcohol consumption
Authors: Gmel Gerhard
Published: August 2002

Missing values in survey instruments are a common problem for survey researchers. It is aggravated in the case of instruments used to measure alcohol consumption: they usually consist of item batteries from which summary measures, such as grams of pure alcohol per day, are constructed, and a missing value (for example, quantity or frequency) in regard to a single item for only one of several beverages results in a missing summary measure across all of the beverages, though the values for the remaining items are known. The present paper examines different approaches to imputation of missing values, feasible with standard statistical software packages. Hot‐deck imputation is shown to have certain advantages, but even single‐value imputation (for example, median imputation) results in values that are comparable to those of the other three imputation methods. Copyright © 2001 John Wiley & Sons, Ltd.
Evaluation of an adjusted chi‐square statistic as applied to observational studies involving clustered binary data
Authors: Jung Sin‐Ho , Ahn Chul , Donner Allan
Published: August 2002

A simple adjustment to the Pearson chi‐square test has been proposed for comparing proportions estimated from clustered binary observations. However, the assumptions needed to assure the validity of this test have not yet been thoroughly addressed. These assumptions will hold for experimental comparisons, but could be violated for some observational comparisons. In this paper we investigate the conditions under which the adjusted chi‐square statistic is valid and examine its performance when these assumptions are violated. We also introduce some alternative test statistics that do not require these assumptions. The test statistics considered are then compared through simulation and an example presented based on real data. The simulation study shows that the adjusted chi‐square statistic generally produces empirical type I errors close to nominal under the assumption of a common intracluster correlation coefficient. Even if the intracluster correlations are different, the adjusted chi‐square statistic performs well when the groups have equal numbers of clusters. Copyright © 2001 John Wiley & Sons, Ltd.
How does institutional change affect heterogeneity among firms?
Authors: Walker Gordon , Madsen Tammy L. , Carini Gary
Published: August 2002

This paper examines the variation in performance of incumbents and entrants following the deregulation of prices and entry in the airline industry. Our approach is similar to earlier studies of interfirm performance heterogeneity across industries. Drawing on theories of industry evolution, we hypothesize that the performance of entrants will have higher variance than incumbents. Further, given the opportunities offered by price deregulation, we propose that incumbents will have higher variance in performance under deregulation than in the earlier regime. The findings indicate that entrant performance heterogeneity is significantly greater than incumbent performance heterogeneity following deregulation, but that the variation in performance among incumbents does not significantly change when deregulation occurs. The second result is surprising given the range of service and process innovations that incumbents initiated. These results suggest that the distinction between entrants and incumbents is critical to future studies of performance variation within and across industries. Copyright © 2002 John Wiley & Sons, Ltd.
Emergent maintenance of ERP: new roles and relationships
Authors: Hirt Sabine Gabriele , Swanson E. Burton
Published: August 2002

How a firm supports its enterprise resource planning system after putting it into production, when its maintenance may be said to be emergent, is critical to the benefits it will eventually derive. Here we report a longitudinal case study of one firm's emergent maintenance of its SAP R/3 system. The study reveals that maintenance‐related roles and relationships differ substantively from those typical of traditional maintenance. We view this firm's maintenance practices to be a harbinger of broader and longer‐term change in maintaining application portfolios. We suggest that the roles and relationships involved are likely to be more complex and therefore more varied in organizational form. In particular, we anticipate: (1) greater sharing of the maintenance task among more participants, with the firm's users often assuming the lead, supported by vendors and third parties; (2) the IS department often playing a more limited, but still key role in providing a portfolio's ongoing support services; and (3) a contingency approach to maintenance, the best approach being a function of specific organizational and systems circumstances. Copyright © 2001 John Wiley & Sons, Ltd.
Management observation and communication theory and organizational information
Authors: Swanson G. A.
Published: August 2002

The identification of basic principles that apply to all aspects of the knowledge domain of a discipline is important. Such fundamentals define the discipline and instruct its development. This process, nevertheless, may be pursued too narrowly—and schools of management thought often do so. These schools of thought generally seek principles and methods that apply equally in all different kinds of organizations. In doing so, they ignore an important aspect of the objects they observe, that organizations are part of a highly dynamic, currently ongoing, evolutionary process. Relatively recent emergents, exchange‐based societies are composed of organizations competing for survival with dynamic, ever‐changing internal purposes and external goals. The competition itself is management and unique management patterns emerge in different organizations. Management science needs a conceptual framework that instructs the development of organization‐specific management theories. Management observation and communication theory (MOCT) is one step in this direction.

MOCT is essentially an integration of linguistic–mathematical theory (L‐M theory) and living systems theory (LST). L‐M theory is a pure system—defined by the interrelationships of its own elements, and thus does not depend on any particular empirical element. LST views existence in the context of concrete systems and particularly from the vantage of living systems. By integrating these general systems theories, MOCT instructs the discovery and development of internal purposes and external goals unique to particular organizations. L‐M theory synthesizes information about an organization's internal processes into general statements of purposes and connects those statements to similarly general statements of external goals. LST focuses MOCT on the processes and structures managers control and in which they compete.

This paper overviews the central ideas and methods of MOCT. Some examples of methods suggested by the theory are given to illustrate how MOCT is applied. Copyright © 2001 International Society for the Systems Sciences.