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PubMed2001

Sample treatment in chromatography-based speciation of organometallic pollutants.

Speciation analysis is nowadays performed routinely in many laboratories to control the quality of the environment, food and health. Chemical speciation analyses generally include the study of different oxidation state of elements or individual organometallic compounds. The determination of the different chemical forms of elements is still an analytical challenge, since they are often unstable and concentrations in different matrices of interest are in the microg l(-1) or even in the ng l(-1) range (e.g., estuarine waters) or ng g(-1) in sediments and biological tissues. For this reason, sensitive and selective analytical atomic techniques are being used as available detectors for speciation, generally coupled with chromatography for the time-resolved introduction of analytes into the atomic spectrometer. The complexity of these instrumental couplings has a straightforward consequence on the duration of the analysis, but sample preparation to separate and transfer the chemical species present in the sample into a solution to be accepted readily by a chromatographic column is the more critical step of total analysis, and demands considerable operator skills and time cost. Traditionally, liquid-liquid extraction has been employed for sample treatment with serious disadvantages, such as consumption, disposal and long-term exposure to organic solvent. In addition, they are usually cumbersome and time-consuming. Therefore, the introduction of new reagents such as sodium tetraethylborate for the simultaneous derivatization of several elements has been proposed. Other possibilities are based in the implementation of techniques for efficient and accelerated isolation of species from the sample matrix. This is the case for microwave-assisted extraction, solid-phase extraction and microextraction, supercritical fluid extraction or pressurized liquid extraction, which offer new possibilities in species treatment, and the advantages of a drastic reduction of the extraction time and the embodiment into on-line flow analysis systems. This new generation of treatment techniques constitutes a good choice as fast extraction methods for feasible species-selective analysis of organometallic compounds under the picogram level, that can be used for national regulatory agencies, governmental and industrial quality control laboratories, and consequently, for manufacturers of analytical instrumentation.

Chromatography↗
PubMed2003

Demographic effects on the Trail Making Test in a drug abuse treatment sample.

Appreciation of the importance of screening for cognitive impairment among substance abusing populations has increased in recent years. In this article, demographic effects on the Trail Making Test (TMT), a test often used for screening for cognitive impairment, are examined in a sample of patients in drug abuse treatment programs. A sample of 5,619 males and 2,902 females was drawn from electronic files of data from the Drug Abuse Treatment Outcome Study (DATOS). The DATOS was a naturalistic cohort study that collected data from 1991 to 1993 in 96 programs in 11 cities in the US. Data were analyzed to determine the effects of demographic variables on the two parts of the TMT in this large sample of patients. Consistent with previous research, demographic variables such as age, gender, education level, and ethnicity were statistically significantly related to both TMT Parts A and B. More importantly, however, the percentage of variance accounted for was quite small. These results suggest that, while clearly present, demographic effects on the TMT are weak.

Adolescent↗
PubMed1997

How constant is an individual's route of heroin administration? Data from treatment and non-treatment samples.

Three routes of heroin use were identified--injecting, 'chasing the dragon' and snorting. Whilst injecting and 'chasing the dragon' accounted for virtually all current heroin use, snorting had been the first route of use for nearly a fifth of heroin users in both the treatment and community samples. Overlap of lifetime experience of the different routes was widespread, with the majority of heroin users in both the treatment and community samples having used heroin by more than one route. Although less than half of the treatment sample had used heroin by injection on the first occasion, more than 90% had injected at least once, and over 80% had at some time used by 'chasing the dragon'. Only a quarter of the community sample had first used heroin by injecting, and yet, by the time of interview, two-thirds of the sample had injected. The majority of durable changes in route of heroin use were towards injecting and 'chasing the dragon', with transitions to snorting being extremely rare. For both the samples, transitions to injecting were twice as frequent as transitions to 'chasing'. Snorting appeared to be an unstable route of use, with almost all who initially snorted their heroin now using by injecting or 'chasing the dragon'.

Administration, Inhalation↗
PubMed2004

A chemometric approach to the comparison of different sample treatments for metals determination by atomic absorption spectroscopy in aceto Balsamico tradizionale di Modena.

A comparison of different digestion procedures has been carried out for the analysis of metal concentration in samples of vinegars and Aceto Balsamico Tradizionale of Modena (ABTM) coming from an unique barrel set. In particular, classical wet, dry ashing, and closed vessel microwave digestion procedure have been utilized and compared for each investigated species. In a few cases, direct metal determination on ABTM (without treatment procedure) is proposed as possible alternative to sample manipulation. Flame atomic absorption spectrometry was used for the quantification of iron and zinc, while graphite furnace atomic absorption spectrometry was used for all the other elements (i.e., chromium, manganese, cobalt, nickel, copper, cadmium, and lead). The comparison among the different sample treatments was carried out by the use of statistical and chemometric tools. In particular, principal component analysis and ANOVA approaches were used to discriminate between the diverse analytical methods. Furthermore, for all the dissolving techniques, the analytical metal recovery was always evaluated by the application of the recovery function on the same sample matrix. In general, the recoveries were fairly good, ranging from 90 to 103%, except for Cd and Pb with dry ashing, which showed recovery values close to 55% and 67%, respectively. As regards the metals concentration of the investigated samples, the experimental data reveal for some species the presence of concentration slightly over the legal limit fixed for wine and wine vinegar.

Acetic Acid↗
PubMed1989

Alcohol use by heroin addicts: evidence for an inverse relationship. A study of methadone maintenance and drug-free treatment samples.

This study examines the relationship between the patterns of use of alcohol and heroin by narcotics addicts, and evaluates the hypothesis--frequently reported during methadone maintenance--that this form of treatment can be causally implicated in an increased consumption of alcohol. Data were obtained on lifetime patterns of alcohol and heroin use of 375 Anglo and Chicano male addicts sampled from two treatment sources: the nonmethadone (drug-free) California Civil Addict Program (CAP) and several Southern California Methadone Maintenance (MM) programs. Repeated-measures MANOVAs revealed that alcohol and heroin consumption were inversely related throughout the addicts' careers. This pattern was evident in the addiction, treatment, and postdischarge stages of Anglo and Chicano addict careers, in both the CAP and MM samples. Consequently, the authors reject the hypothesis that increased alcohol consumption is caused solely by addicts' participation in methadone maintenance treatment. Rather, the findings suggest that addicts' alcohol use during methadone treatment reflects a lifetime pattern of increased alcohol use following any decline in heroin intake.

Adult↗
PubMed2006

Automated sample treatment by flow techniques prior to liquid-phase separations.

Sample preparation (SP) is an integral and important part of an analytical process. Lately, SP has been the topic of increased interest in research and development of novel advanced technologies. Major needs in this aspect are miniaturization, automation, and enrichment. Among other methodologies, flow techniques can be conveniently and effectively coupled to liquid-phase separation technologies for on-line sample preparation. This paper reviews the current trends in on-line automated sample preparation by flow-through techniques prior to liquid-phase separations. Strategies and interfaces developed to couple flow techniques with liquid chromatography, capillary electrophoresis, and mass spectrometry are described. Advantages and limitations of the coupling are discussed. The paper also highlights certain selected applications of these coupled systems.

Chromatography, Liquid↗
PubMed1998

The validity of self-reported cocaine use in a criminal justice treatment sample.

Recent studies comparing self-admitted cocaine use with hair and urine test results have raised concerns about underreporting due to variations across situations and settings. Because of the frequent need for self-report data in conducting treatment evaluations, more information is needed on factors that affect the credibility of this information. The present study examines records of cocaine use collected as part of an evaluation of prison-based treatment (N=396). Specifically, self-reported cocaine use from 6-month postrelease follow-up interviews, completed with treatment graduates and a comparison sample of parolees who were eligible but not sent to treatment, was examined in relation to urine and hair test results. Overall, cocaine use was underreported when compared to hair test results, but underreporting was lower for program graduates than for the untreated comparison group. Furthermore, program graduates originally admitted to prison on a drug-related arrest were the most likely to underreport cocaine use, seemingly due to a heightened concern about potential consequences, such as returning to prison on another drug-related charge. Given that the validity of self-report for high-risk individuals varies greatly and is difficult to predict across studies, future research with criminal justice samples should continue to assess the validity of these measures under specific research conditions and for diverse types of individuals.

Adult↗
PubMed2001

Using the Trail Making test to screen for cognitive impairment in a drug abuse treatment sample.

The Trail Making test (TMT) is a brief paper and pencil neuropsychological test often used for screening for cognitive impairment. The value of the TMT is examined in a sample of 5619 males and 2902 females was drawn from electronic files of data from the Drug Abuse Treatment outcome Study (DATOS), a naturalistic, prospective cohort study that collected data from 1991-1993 in 96 programs in 11 cities in the United States. Data were analyzed to determine the effects of specific drugs of abuse on parts A and B of the TMT in this large sample of patients in drug abuse treatment programs. Most subjects, regardless of type of drug abused, on TMT parts A and B appeared to fall within normal limits relative to commonly accepted cutoff scores. These results suggest that the TMT parts A and B would have great value as screening measures for cognitive impairment in a drug abuse treatment population.

Adult↗
PubMed2000

Addiction severity index data from general membership and treatment samples of HMO members. One case of norming the ASI.

The Addiction Severity Index (ASI) is a widely used interview among substance-dependent populations in treatment. Its value as a treatment planning and evaluation tool has been diminished by the lack of comparative data from nonclinical samples. The present study included four scales from the ASI collected on samples of adult subscribers to a large health maintenance organization (HMO) in northern California, as well as an adult clinical sample from the same geographic region with the same HMO insurance, thereby offering informative contrasts. Interviews (N = 9,398) of non-alcohol-dependent or abuse adults from a random sample of members of a large HMO were analyzed. We collected complete ASI data on the alcohol, drug, medical, and psychiatric composite scales and partial data on the employment scale. A sample of 327 adult members of the same HMO from one of the counties included in the survey, who were admitted to treatment for alcohol and/or drug addiction, was administered the same ASI items at treatment admission. Analyses compare problem severities in the two samples by age and gender. The general membership reported some problems in most of the ASI problem areas, although at levels of severity that were typically far below those seen in the clinical sample. General membership and clinical samples were somewhat similar in medical status and in employment. As expected, alcohol, drug, and psychiatric status were much more severe in the clinical sample. The data from the HMO general membership sample provide one potential comparison group against which to judge the severity of problems presented by drug- and alcohol-dependent patients at treatment admission and at posttreatment follow-up. The authors discuss the implications for treatment planning and the evaluation of treatment outcome.

Adolescent↗
PubMed1995

Social relationships and abstinence from cocaine in an American treatment sample.

In an extension of earlier work relating social-relationship variables to post-treatment abstinence from abused drugs, 104 cocaine users were studied for 6 months after completing drug treatment. Social-relationship variables included social integration, perceived support and social-network cocaine use. The effects of social relationships on cocaine abstinence tended to be conditional on race. Greater social integration predicted abstinence for Caucasian Ss (n = 54), but not African-Americans (n = 50). Similar results occurred for perceived support. Social network drug-use data also showed race differences: the absence of current cocaine users and the presence of former users predicted abstinence only for Caucasians. Interpretation of these findings is complicated by the relationship we observed between race and route of cocaine administration, with African-American Ss far more likely than Caucasians to be crack smokers or injection users as compared to intranasal users. The effects of race could not be disentangled from the effects of route. Future studies of social relationships and cocaine abstinence should focus on identifying social factors that are protective for African-Americans and for smokers/injectors. Such studies are critical precursors to designing successful social-support interventions.

Adult↗
PubMed2003

Alcohol use outcomes and heavy drinking at 4-5 years among a treatment sample of drug misusers.

This paper investigates alcohol outcomes and heavy drinking among 418 drug misusers from the National Treatment Outcome Research Study who completed followup interviews at 1, 2, and 4-5 years. About a quarter of the sample were drinking heavily at intake. Alcohol consumption at followup was predicted by drinking prior to intake, and about a quarter of those who were classified as alcohol abstainers, medium-level drinkers, or heavy drinkers at intake, remained in the same drinking category at all assessment points. Drinking outcomes were not related to opioid use. Heavy drinkers at followup were more likely to be using non-opioid drugs. The poor drinking outcomes are a matter for concern. Drug misusers with concurrent alcohol problems may require special treatment provision. The extent of heavy drinking among drug misusers both before and after treatment indicates a need to develop and strengthen programs and interventions to tackle alcohol-related problems in this patient group.

Adult↗
PubMedDate not supplied

Influence of sample treatment on ESR signal of irradiated citrus.

ESR spectra of the hard seed cover and kernel coating of irradiated orange and tangerine fruits were obtained under different sample drying conditions to analyze the effect of treatment on ESR line at g = 2.0033 (line A). The spectra shows almost the same lines that appear in stalks, achenes, seeds and skins of fresh fruit. The peak-to-peak intensity of the line A of the spectra shows a linear variation with dose in the range studied (up to 5 kGy) under controlled sample preparation. Q-band ESR spectra shows that this line is composed for three different lines from different species. A1, A2 and A3. The A2 and A3 lines are associated with dose but grow also during drying of the sample and are probably due to 'cellulosic' components of the seed cover. The A1 line appears only when sample is dried and is probably associated with the quinones of the internal kernel coat.

Citrus↗
PubMed2001

Self-reports of physical, sexual and emotional abuse in an alcoholism treatment sample.

OBJECTIVE: There is a growing appreciation that emotional, physical and sexual abuse events are frequently part of the life histories of individuals in treatment for alcohol disorders. The present study examines reports of lifetime abuse in a clinical trial for treatment of alcohol dependency. METHOD: Data were obtained from baseline assessments conducted with participants (N = 1,726; 1,307 men) entering Project MATCH, a multisite clinical trial conducted at nine geographically dispersed research sites. Differences on a broad range of participant characteristics were examined by gender and by reported abuse type. RESULTS: More than half (59%) of the participants reported lifetime abuse. Women were more likely (77%) to report abuse than were men (54%). A lower proportion of men than women (6% vs 31%) reported experiencing both physical and sexual abuse. Gender differences were found on the majority of psychosocial measures. Comparisons of the psychosocial measures by abuse type generally indicated that participants without abuse histories had better functioning than did participants reporting abuse. CONCLUSIONS: The high frequency of lifetime abuse in this geographically dispersed sample underscores the necessity for including assessment of emotional, physical and sexual abuse with alcoholism treatment seeking populations. Participants reporting such events may require other treatment in addition to that for alcohol dependency.

Adult↗
PubMed2005

Five-year trajectories of health care utilization and cost in a drug and alcohol treatment sample.

BACKGROUND: The study examined the effect of individual characteristics on longitudinal patterns of health care utilization and cost among individuals entering chemical dependency (CD) treatment. METHOD: Structured interviews and computerized administrative databases were linked to obtain severity, utilization and cost data. Total medical costs and their components were examined for the 6 months prior to intake through 5 years post-intake. Statistical analyses were conducted using the hierarchical linear modeling framework. RESULTS: Age was positively correlated with total medical costs. Women had higher inpatient utilization and higher inpatient, primary care and total cost at baseline (p<.05). However, they had steeper decline in primary care costs. While age was not related to inpatient and ER use at baseline (after controlling for psychiatric and medical severity), older individuals had smaller declines in hospital days and inpatient cost over time. Individuals with high medical and psychiatric severity had higher utilization and costs (p<.01). Those who were abstinent had higher costs. CONCLUSIONS: There are important differences in patient characteristics and treatment outcomes that influence utilization and cost trajectories. The relationship between medical severity at intake and primary care cost pre-intake among patients with drug and alcohol problems suggests an opportunity to identify and treat drug and alcohol problems in primary care settings. It also suggests that medical evaluations and treatment should not be overlooked during CD treatment. The positive association between abstinence and trajectories of primary care and total medical costs suggests that maintaining abstinence over a long term requires some kind of continuing care either in primary care settings or via additional contacts with specialty CD departments.

Adult↗
PubMed1996

DSM-IV alcohol dependence and drug abuse/dependence in a treatment sample of whites, blacks and Mexican Americans.

This paper examines the association between DSM-IV alcohol dependence, drug use and DSM-IV drug/abuse dependence in a sample of White (n = 256), Black (n = 263) and Mexican American (n = 212) men consecutively admitted to five alcohol treatment programs in a Northern California county. Results show that drug use is higher among Blacks and Mexican Americans than among Whites. About 35% of the Whites 43% of the Blacks and 35% of the Mexican Americans are both alcohol and drug dependent. Among alcohol dependent individuals, about 44% of the Whites, 72% of the blacks and 52% of the Mexican Americans report using at least one drug other than alcohol once a week or more in the 12 months previous to the interview. The drug most frequently used by Whites is marijuana, followed by cocaine and amphetamines. The drug most frequently used by Blacks and Mexican Americans is cocaine, followed by marijuana. Severity of drug dependence is inversely related to severity of alcohol dependence among Whites. Alcohol treatment programs for Whites, Blacks and Mexican Americans must offer assessment, treatment matching and relapse prevention that takes into consideration this high prevalence of drug use and dependence.

Adolescent↗
PubMed2003

The Maudsley bipolar disorder project. Clinical characteristics of bipolar disorder I in a Catchment area treatment sample.

The clinical characteristics of bipolar I disorder (BD1) have prognostic and therapeutic importance. The aim of this study was to examine the effect of demographic and clinical variables on the course of BD1. We reviewed the case notes of all BD1 patients (n = 63) receiving treatment in a London psychiatric service during a 1-month period. Depressive and manic onsets were equally likely without any gender difference. The earlier the age of onset, the more likely it was for patients to experience psychotic features. Only depressive onsets predicted a higher number of episodes of the same polarity. Male gender and substance abuse were associated with younger age at first presentation, while women with co-morbid substance abuse had more manic episodes. Male patients were more likely than females to be unemployed or single.

Adult↗
PubMed1985

Electroimmunoassay of rat apolipoproteins A-I, A-IV, and E. A procedure for sample treatment to increase the sensitivity in diluted fractions.

Methods for the quantitative determination of rat apolipoproteins A-I, A-IV, and E by electroimmunoassay are described. Apolipoproteins present in diluted samples of biological fluids (approx. 2 ml) were concentrated by precipitation with deoxycholate and trichloroacetic acid. The protein pellets were solubilized in 0.1 ml of 0.5 M NaOH and these samples were delipidated with tetramethylurea and assayed. This protocol enables the measurement of apolipoprotein concentrations that are at least 10 times lower than normally detectable; 0.2 micrograms of apolipoprotein A-IV, 0.2 micrograms of apolipoprotein A-I, and 0.8 micrograms of apolipoprotein E can be easily detected in samples of 2 ml.

Animals↗
PubMed1991

A sensitive sandwich enzyme-linked immunosorbent assay of rat apolipoprotein A-I: effect of various sample treatments on apolipoprotein A-I immunoreactivity and an application to young and aged rat sera.

A highly sensitive sandwich enzyme-linked immunosorbent assay for rat apo A-I was developed. Samples and standards were added to each well of microtiter plates precoated with immunoaffinity-purified IgG. Bound apo A-I was detected with immunoaffinity-purified Fab'-horseradish peroxidase conjugate by a colorimetric method. The sensitivity reached 2.5 pg/well, and the working range for the measurement of serum apo A-I concentration was 0.1 to 1.0 ng/well. The mean intra- and interassay coefficients of variation were 2.8 and 4.1%, respectively. The epitopes of apo A-I in serum were effectively exposed by the use of 6 mol/liter guanidine.HCl. Serum apo A-I concentrations in 36- to 40-week-old rats (62.3 +/- 8.6 mg/dl, mean +/- SD, n = 16) were significantly higher (P less than 0.05) than those in 8- to 12-week-old rats (55.1 +/- 4.3 mg/dl, n = 9). But the age-related change of serum apo A-I was much smaller than that of serum apo E. Apo A-I was contained in smaller HDL particles (or HDL2) in normal rat serum.

Aging↗