bluuebunny/crossref_metadata_2025_split huggingface dataset:
Derivatization of amino acids with N,N‐dimethyl‐2,4‐dinitro‐5‐fluorobenzylamine for liquid chromatography/electrospray ionization mass spectrometry
Authors: Liu Zhongfa , Minkler Paul E. , Lin De , Sayre Lawrence M. 
Published: April 2004

AbstractDerivatization, separation and identification of amino acids with a novel compound, N,N‐dimethyl‐2,4‐dinitro‐5‐fluorobenzylamine (DMDNFB), using high‐performance liquid chromatography/electrospray ionization mass spectrometry (HPLC/ESI‐MS) was demonstrated. Compared to derivatization with 2,4‐dinitrofluorobenzene (DNFB), DMDNFB‐derivatized amino acids and dipeptides exhibit much larger ion current signals in the commonly used ESI positive mode, which was attributed to the introduction of the N,N‐dimethylaminomethyl protonatable site. Copyright © 2004 John Wiley & Sons, Ltd.
Identification by electrospray tandem mass spectrometry of spin‐trapped free radicals from oxidized 2‐oleoyl‐1‐palmitoyl‐sn‐glycero‐3‐phosphocholine
Authors: Reis A. , Domingues P. , Ferrer‐Correia A. J. V. , Domingues M. R. M. 
Published: April 2004

AbstractGPC radical species formed during oxidation of a glycerophosphocholine (16:0/18:1) under the Fenton reaction conditions were detected using a spin trap, 5,5‐dimethyl‐1‐pyrrolidineN‐oxide (DMPO). The stable spin‐trapped radical adducts were identified by mass spectrometry (MS) using electrospray (ES) as ionization method and characterized by tandem mass spectrometry (MS/MS). Radical adducts of oxidized freesn‐2 fatty acid and of oxidized intact GPC, containing one, two and three additional oxygen atoms, were assigned. DMPO adducts of oxidized intact GPC were observed as singly and doubly charged ions in ES‐MS, while adducts of oxidized free fatty acids were observed as singly charged ions. Oxidized freesn‐2 fatty acids and intact GPC‐DMPO adducts correspond to carbon‐ and oxygen‐centered radicals that were identified by MS/MS as alkyl, hydroxy‐alkyl, alkoxyl, hydroxy‐alkoxyl, peroxyl and hydroperoxide‐alkoxyl spin adducts. The DMPO molecule was attached predominantly at C9of the oleic chain. The fragmentation pathway of spin adducts with two DMPO molecules strongly suggests the presence of species that were simultaneously carbon‐ and oxygen‐centered radicals. Several fragments identified are consistent with the presence of isomeric structures contributing to the same ions. Copyright © 2004 John Wiley & Sons, Ltd.
Comparison of product ion spectra obtained by liquid chromatography/triple‐quadrupole mass spectrometry for library search
Authors: Gergov Merja , Weinmann Wolfgang , Meriluoto Jussi , Uusitalo Jouko , Ojanperä Ilkka 
Published: April 2004

AbstractReproducibility of product ion spectra acquired using a liquid chromatography/triple‐quadrupole mass spectrometry (LC/MS/MS) instrument over a 4‐year period, and with three other LC/MS/MS instruments, one from the same manufacturer and two from a different manufacturer, was examined. The MS/MS spectra of 30 drug substances were generated in positive electrospray ionization mode at low, medium, and high collision energies (20, 35, and 50 eV). Purity and Fit score percentages against a 400‐compound LC/MS/MS spectral library were calculated using an algorithm in which fragment intensity ratios and weighting factors were included. The long‐term reproducibility study was conducted using a brand A instrument; after 4 years the reproducibility of the product ion spectra was still 94%, expressed as average Purity score. The inter‐laboratory study involved two parts. Firstly, two LC/MS/MS spectral libraries, created independently in separate laboratories using brand A instruments, were compared with each other. The average Fit and Purity scores of spectra from one library against the other were better than 93 and 91%, respectively, when the same collision energies were used. Secondly, for the comparison of product ion spectra between brand A and brand B instruments, fragmentation conditions were first standardized for amitriptyline as the standard analyte. The average Fit scores of brand B spectra against the brand A spectral library varied between 79 and 85% at all three collision energies. These results indicate that, after standardizing the instrumental conditions, LC/MS/MS spectral libraries of drug substances are suitable for inter‐laboratory use. Copyright © 2004 John Wiley & Sons, Ltd.
Drug use by Brazilian students: associations with family, psychosocial, health, demographic and behavioral characteristics
Authors: De Micheli Denise , Formigoni Maria Lucia O. S. 
Published: April 2004

ABSTRACTAims  In the last few years, epidemiological studies in Brazil have detected significant increases in the use and abuse of psychoactive drugs by adolescents; however, there is a paucity of data on the factors associated with this use.Objectives  To assess the prevalence of drug use by students from public schools in a Brazilian city and to evaluate the influence of age, school achievement, family, psychosocial, health, demographic and behavioural characteristics on regular drug use.Design  This cross‐sectional study was conducted using a representative sample of 6417 students attending public schools in the city of Barueri, Brazil and included adolescents from the 5th grade of elementary school to the 3rd year of high school. The Brazilian version of the Drug Use Screening Inventory (DUSI‐R) was administered in the classroom by trained educational advisers without teachers being present.Findings  Prevalence rates for the previous month were: alcohol: 48%, tobacco: 22.5%, cannabis: 14%, inhalants/solvents: 5%, cocaine: 3%, tranquillizers: 0.5%, amphetamines: 0.9%, anabolic steroids: 0.1% and ecstasy: 0.9%. With the exceptions of tranquillizers and amphetamines, the older students reported significantly higher frequencies and amounts of drug use than the younger ones. Boys reported a significantly higher consumption of alcohol, cannabis, cocaine and ecstasy than girls, as well as higher percentages of frequent/heavy use. Logistic regression analysis detected that poor school achievement, a poor or bad relationship with those with whom they live, studying in the evening period, presence of antisocial behaviour, family problems and friends who use drugs were factors significantly associated with drug use.Conclusions  The findings suggest that preventive programmes should be more comprehensive in scope, rather than focusing only on information about the negative consequences of drug use.
Depression and hostility as predictors of long‐term outcomes among opiate users
Authors: Rao Sandhya R. , Broome Kirk M. , Simpson D. Dwayne 
Published: April 2004

ABSTRACTAims  This study used data from the national Drug Abuse Treatment Outcome Studies (DATOS) to investigate the associations that pre‐treatment depression and hostility have with drug use and criminal behavior at 1 year and 5 year follow‐up in patients with and without additional treatment involvement in the year prior to each follow‐up.Design  Following a naturalistic, non‐experimental evaluation design, admissions to methadone treatment were followed up approximately 1 and 5 years later. Data analysis was conducted using multiple logistic regression.Setting  Eighteen programs from DATOS were included.Participants  An analytic sample consisting of 727 patients at 1 year follow‐up and 432 patients at 5 year follow‐up was included.Findings  Multiple logistic regression analyses revealed that greater depression predicted less drug use in the year preceding each follow‐up, whereas greater hostility predicted increased drug use and more arrests at each follow‐up. Furthermore, these predictive relationships appeared only among individuals not involved in additional treatment.Conclusions  Depression and hostility showed opposite associations with outcomes, underscoring the need to assess these psychological conditions separately and tailor treatment plans appropriately.
Hepatitis C and its risk management among drug injectors in London: renewing harm reduction in the context of uncertainty
Authors: Rhodes Tim , Davis Mark , Judd Ali 
Published: April 2004

ABSTRACTAim  Recognizing the dearth of qualitative research on hepatitis C virus (HCV) infection associated with injecting drug use in the UK, this paper summarizes qualitative insights from a study exploring the social relations of HCV risk management among drug injectors in London.Method  Adopting an inductive approach to data collection and analysis, 59 depth tape‐recorded qualitative interviews were undertaken in 2001 with drug injectors recruited via drug user networks.Results  While access to injecting equipment was reportedly good, needle and syringe sharing continued in exceptional circumstances and in the context of ‘trust relationships’. Analyses of drug injectors’ accounts of variations of ‘I never share’ showed that this construction denoted less a descriptor of actual risk behaviour than presentation of perceived risk status. Paraphernalia sharing, including spoons and filters, was common. There was much confusion and uncertainty concerning HCV knowledge, including its medical and transmission risks. Injectors were aware of the provisionality and partiality of their HCV knowledge. Confusion also surrounded the meaning of HCV antibody test results, with some feeling that their positive diagnosis had been ‘trivialized’ by their experiences of HCV testing. Injectors tended to make sense of HCV risk in relation to HIV. With most viewing HCV prevalence as high and HCV transmission as an inevitable consequence of injecting, HCV risk was perceived as ubiquitous and unavoidable.Conclusions  There is an urgent need to renew UK policies of harm reduction in order to support perceptions that HCV is avoidable and preventable.
New Mexico's 1998 drive‐up liquor window closure. Study I: effect on alcohol‐involved crashes
Authors: Lapham Sandra C. , Gruenwald Paul J. , Remer Lillian , Layne Larry 
Published: April 2004

ABSTRACTAims  To determine the spatial relationship between drive‐up liquor window locations and alcohol‐related traffic crashes for 2 years before and after New Mexico banned drive‐through alcohol sales.Design  Current liquor licenses, crash data, roadway information and US Census data were used in this analysis. Cross‐sectional and longitudinal regression analyses were applied to the entire state, and to Albuquerque only.Findings  Of all NM liquor licenses, 189 (9%) included drive‐up sales, which co‐occurred with on‐ or off‐premise licenses (94%). The rate of non‐pedestrian alcohol‐related crashes relative to non‐pedestrian total crashes showed an increasing trend prior to closure and a decreasing trend after the closure. Cross‐sectional analyses in Albuquerque revealed that the percentage of alcohol‐involved crashes was not related to densities of on‐ or off‐premise outlets per kilometer of roadway, or to percentage of drive‐up outlets. Statewide, the percentage of drive‐up outlets was not significantly related to the percentage of alcohol‐related crashes within census tracts but was associated positively with the percentage of alcohol‐related crashes in surrounding census tracts. There was no statistically significant relationship between number of drive‐ups and percentage of alcohol‐related crashes in either longitudinal model.Conclusions  Despite the declining rate of alcohol‐related crashes following closure of drive‐up liquor windows, both in Albuquerque and statewide, regression models using spatial data do not demonstrate definitively an association between the decline and the closure of the drive‐up liquor windows.
Effect of pre‐treatment with nicotine patch on withdrawal symptoms and abstinence rates in smokers subsequently quitting with the nicotine patch: a randomized controlled trial
Authors: Schuurmans Macé M. , Diacon Andreas H. , Van Biljon Xandra , Bolliger Chris T. 
Published: April 2004

ABSTRACTAims  To determine whether 2‐week pre‐treatment with transdermal nicotine influences withdrawal symptoms or success rate of subsequent smoking cessation using nicotine patches.Design  Randomized controlled trial.Setting  Smoking cessation clinic.Participants  Healthy smokers (n = 200, 45% female) were allocated randomly to either active nicotine‐patch (AP, 15 mg daily, n = 100) or placebo‐patch (PP, n = 100) pre‐treatment. Baseline characteristics were well balanced except for daily cigarette consumption: mean (± SD) 23.1 (8) and 26.4 (11) for AP and PP groups, respectively (P = 0.021).Intervention  At the screening visit (− 2 weeks) subjects were counselled and started pre‐treatment with daily patches (AP or PP). From the quit date (week 0) onwards all subjects received active nicotine patches for 12 weeks (15 mg daily for 8 weeks, 10 and 5 mg daily for 2 weeks each) and counselling.Measurements  Follow‐up visits included measurement of exhaled carbon monoxide at the quit date, 2, 6, 10 and 26 weeks. Subjects documented daily cigarette consumption and severity of withdrawal symptoms (Wisconsin scale) from − 2 weeks to week 2. Outcome measures were withdrawal symptoms composite score and abstinence rates.Findings  There was no significant difference in withdrawal symptoms, but more subjects in the AP group were smoke‐free during the 6‐month study period. Overall sustained abstinence was documented in 17% of subjects at 6 months; 22% and 12% for AP and PP, respectively (P = 0.03). Retrospective subgroup analysis showed for subjects smoking >16 cigarettes/day sustained cessation rates were 22% and 9% for AP and PP, respectively (P = 0.01). No difference in adverse event rates was observed.Conclusions  Nicotine patch pre‐treatment before cessation did not reduce early withdrawal symptoms but increased sustained abstinence rates at 6 months. The nicotine pre‐treatment was equally effective in light and heavy smokers.
Addiction and spirituality
Authors: Cook Christopher C. H. 
Published: April 2004

ABSTRACTBackground  Spirituality is a topic of increasing interest to clinicians and researchers interested in addiction.Aims  To clarify the way(s) in which the concept of spirituality is understood and employed in practice by clinicians and researchers who publish papers on addiction and spirituality, and to develop a definition or description of spirituality which might receive widespread assent within the field.Design  A descriptive study of 265 published books and papers on spirituality and addiction.Findings  The study revealed a diversity and lack of clarity of understanding of the concept of spirituality. However, it was possible to identify 13 conceptual components of spirituality which recurred within the literature. Among these conceptual components of spirituality, ‘relatedness’ and ‘transcendence’ were encountered most frequently. ‘Meaning/purpose’, ‘wholeness (non‐)religiousness’ and ‘consciousness’ were encountered less frequently in the papers on addiction and spirituality than in an unsystematically ascertained sample of papers concerned with spirituality in relation to other areas of psychology and medicine. However, biases in the literature are notable. For example, the great majority of publications are from North America and the field is dominated by interest in Twelve‐Step and Christian spirituality.Conclusion  Spirituality, as understood within the addiction field, is currently poorly defined. Thirteen conceptual components of spirituality which are employed in this field are identified provisionally and a working definition is proposed as a basis for future research.
Twenty‐year trends in illicit drug use among young Israelis completing military duty
Authors: Neumark Yehuda D. , Grotto Itamar , Kark Jeremy D. 
Published: April 2004

ABSTRACTAim  This study examines patterns of illicit drug use in a national sample of young men and women in Israel over a 20‐year period.Design  Annual cross‐sectional data are analysed from an ongoing systematic sample of soldiers being discharged from active military service during the years 1982–2001.Setting  An anonymous questionnaire is self‐administered to soldiers on the day of discharge in an unsupervised setting.Participants  Between 1200 and 2800 individuals participated in the survey annually. A total of 40 518 people were included in the analysis. This sample frame is reflective of all Israel Defense Forces (IDF) releasees below the rank of Captain. Military recruits in Israel comprised about 80% of the country's 18‐year‐old Jewish male cohort in any given year, and about two‐thirds of the female population of this age.Findings  Time‐trends of drug use in Israel parallel those in the United States and European countries, although at much lower rates. Several indicators suggest a recent increase, particularly among women. Drug use is strongly inversely related to education level. Marijuana accounts for 65–75% of drug use in this young adult population.Conclusion  Jewish cultural background and the military policy of zero tolerance are assumed contributors to the low drug use levels. Recent upward trends suggest that intensified prevention, surveillance and research efforts are in order.
The contribution of research to Australian policy responses to heroin dependence 1990–2001: a personal retrospection*
Authors: Hall Wayne 
Published: April 2004

ABSTRACTPeriodic public concern about heroin use has been a major driver of Australian drug policy in the four decades since heroin use was first reported. The number of heroin‐dependent people in Australia has increased from several hundreds in the late 1960s to around 100 000 by the end of the 1990s. In this paper I do the following: (1) describe collaborative research on heroin dependence that was undertaken between 1991 and 2001 by researchers at the National Drug and Alcohol Research Centre; (2) discuss the contribution that this research may have made to the formulation of policies towards the treatment of heroin dependence during a period when the policy debate crystallized around the issue of whether or not Australia should conduct a controlled trial of heroin prescription; and (3) reflect on the relationships between research and policy‐making in the addictions field, specifically on the roles of investigator‐initiated and commissioned research, the interface between researchers, funders and policy‐makers; and the need to be realistic about the likely impact of research on policy and practice.
Self‐expanding metal stents for the palliation of malignant gastroduodenal obstruction in patients unsuitable for surgical bypass
Authors: Lindsay J. O. , Andreyev H. J. N. , Vlavianos P. , Westaby D. 
Published: April 2004

SummaryBackground : The primary therapeutic goals in patients with gastroduodenal obstruction secondary to advanced malignancy are the re‐introduction of an enteral diet and early discharge. The endoscopic placement of expandable metal stents has been proposed as an alternative technique for palliation in patients not suitable for surgery.Aim : To review our experience with gastroduodenal metal stent insertion for the palliation of malignant gastric and duodenal obstruction.Methods : A retrospective review was conducted of the notes of all patients who underwent gastroduodenal stent insertion in our unit.Results : Forty patients (mean age, 64.5 years; range, 34–93 years) underwent insertion of an enteral stent for malignant gastroduodenal obstruction. The primary tumour was gastric in 20 patients, pancreatico‐biliary in 15 and metastatic in five. A stent was successfully placed in all cases. Thirty‐two patients have subsequently died, the median (range) survival being 7 weeks (1 week to 10 months). Thirty‐three patients (82.5%) were discharged from hospital. During follow‐up, 12 patients (30%) returned to a solid diet, 20 (50%) required a soft diet, six (15%) tolerated liquids and two (5%) were unable to tolerate any enteral nutrition.Conclusion : The use of enteral stents achieves good palliation, allowing discharge from hospital and re‐introduction of an enteral diet.
SR 48692, a specific neurotensin receptor antagonist, has no effect on oesophageal motility in humans
Authors: Zerbib F. , Piche T. , Charles F. , Galmiche J.‐P. , Bruley Des Varannes S. 
Published: April 2004

SummaryBackground : The administration of exogenous neurotensin can reduce the lower oesophageal sphincter pressure, but it is unclear whether this effect is pharmacological or physiological.Aim : A specific neurotensin receptor antagonist (SR 48692) was used to assess the effect of endogenous neurotensin on lower oesophageal sphincter function.Methods : Twenty‐four healthy male subjects were included in a double‐blind, placebo‐controlled, randomized, cross‐over study designed to determine the effects of two single doses (90 and 300 mg, preceded by a loading dose) of SR 48692 on the resting lower oesophageal sphincter pressure, transient lower oesophageal sphincter relaxations, primary oesophageal peristalsis and oesophageal acid exposure. Oesophageal pH and motility recordings were performed during 1 h of fasting and 3 h post‐prandially. Plasma neurotensin‐like immunoreactivity release was determined by radioimmunoassay.Results : During fasting, the lower oesophageal sphincter pressure, transient lower oesophageal sphincter relaxation rate and reflux episodes were similar with the two doses of SR 48692 and placebo. Meal ingestion induced a rise in plasma neurotensin‐like immunoreactivity, a decrease in lower oesophageal sphincter pressure and an increase in both the transient lower oesophageal sphincter relaxation rate and the number of reflux episodes, which were not significantly modified by SR 48692. SR 48692 did not affect oesophageal primary peristalsis.Conclusion : This study shows that SR 48692, a specific neurotensin 1 receptor antagonist, has no effect on oesophageal motility in humans.
How useful are the rodent animal models of gastric adenocarcinoma?
Authors: Pritchard D. M. , Przemeck S. M. C. 
Published: April 2004

SummaryGastric cancer is the second most common cause of cancer‐related mortality world‐wide. In most cases, it develops via the pre‐malignant stages of atrophic gastritis, intestinal metaplasia and dysplasia, following Helicobacter pylori infection of susceptible individuals. A number of rodent models have recently provided valuable insights into the host, bacterial and environmental factors involved in gastric carcinogenesis. Wild‐type rodents do not develop gastric adenocarcinoma, but early studies showed that the disease could be induced in several rodent species by chemical carcinogens. More recently, it has been demonstrated that gastric adenocarcinoma can be induced in Mongolian gerbils by H. pylori infection and in C57BL/6 mice by long‐term H. felis infection. These models have allowed the importance of Helicobacter virulence genes, host factors, such as gender, strain and immune response, and environmental factors, such as dietary salt, to be explored. A number of transgenic mice with alterations in various pathways, including the immune response, gastrin biosynthesis, parietal cell development, growth factors and tumour suppressors, have also provided models of various stages of gastric carcinogenesis. One model that has proved to be particularly valuable is the hypergastrinaemic INS‐GAS mouse, in which gastric carcinoma develops spontaneously in old animals, but the process is greatly accelerated by Helicobacter infection.