Recommended practice for calibrating vacuum gauges of the ionization type.

This article represents a recommended practice for the calibration of ionization gauges using the comparison method. In this method, ionization gauges are compared to a working standard that has an SI traceable calibration. The ionization gauge is either of the hot-cathode ionization type or the cold-cathode ionization type. Details of the calibration apparatus, the principle of operation of the gauges, data analysis, uncertainty budget, and reporting the uncertainty are given.

Progress on vacuum-to-air mass calibration system using magnetic suspension to disseminate the Planck-constant realized kilogram.

The kilogram is the unit of mass in the International System of units (SI) and has been defined as the mass of the International Prototype Kilogram (IPK) since 1889. In the future, a new definition of the kilogram will be realized by fixing the value of the Planck constant. The new definition of the unit of mass will occur in a vacuum environment by necessity, so the National Institute of Standards and Technology (NIST) is developing a mass calibration system in which a kilogram artefact in air can be directly compared with a kilogram realized in a vacuum environment. This apparatus uses magnetic suspension to couple the kilogram in air to a high accuracy mass balance in vacuum.

The Dissemination of Mass in the United States: Results and Implications of Recent BIPM Calibrations of US National Prototype Kilograms.

The National Institute of Standards and Technology (NIST) is responsible for the dissemination of the unit of mass within the United States of America through the national prototype kilogram K20 and its check standard K4. These platinum-iridium artifacts have been in use since 1889 and are periodically sent to the International Bureau of Weights and Measures (BIPM) for recalibration. The following is a brief description of the roles of the national prototype kilograms in the dissemination of mass in the United States of America, and the implications for NIST mass calibration customers of the most recent recalibrations of K20 and K4.

The New Kilogram Definition and its Implications for High-Precision Mass Tolerance Classes.

The SI unit of mass, the kilogram, is the only remaining artifact definition in the seven fundamental units of the SI system. It will be redefined in terms of the Planck constant as soon as certain experimental conditions, based on recommendations of the Consultative Committee for Mass and Related Quantities (CCM) are met. To better reflect reality, the redefinition will likely be accompanied by an increase in the uncertainties that National Metrology Institutes (NMIs) pass on to customers via artifact dissemination, which could have an impact on the reference standards that are used by secondary calibration laboratories if certain weight tolerances are adopted for use. This paper will compare the legal metrology requirements for precision mass calibration laboratories after the kilogram is redefined with the current capabilities based on the international prototype kilogram (IPK) realization of the kilogram.

Screening American Indian/Alaska natives for alcohol abuse and dependence in medical settings.

As a result of the lethal effect that alcohol has had on the American Indian and Alaska Native population, it is vital to aggressively screen for hazardous/harmful use, alcohol abuse and dependence among American Indian/Alaska Natives entering medical settings. This is especially true in primary care settings where individuals may come in for a host of medical problems and may not be directly seeking help in reducing their use of alcohol. There are a number of strategies to screen for hazardous/harmful use and abuse of alcohol in primary care settings. These strategies include: screening questions/questionnaires, biochemical markers and collateral information. There is a growing body of literature which validates the use of some of the standard screening questionnaires among adult American Indians and Alaska Natives including the AUDIT and CAGE. Additionally, there are two instruments that have been validated in two vulnerable American Indian and Alaska Native populations: adolescents and pregnant women. These instruments are the CRAFFT for adolescents and the SAQ for pregnant women. There are currently no studies that were identified in this review that looked specifically at biochemical markers for American Indian and Alaska Natives. Finally, it is important to interview a patient's collaterals both to identify early problems with alcohol and as an adjunct to engaging the patient into treatment. Supportive collaterals can assist the patient to decrease or stop the use of alcohol and engage in treatment.

Changes in methadone maintenance therapy during and after pregnancy.

OBJECTIVE: The aim of this study is to better understand anticipated changes in daily methadone doses as a guide for prescription during pregnancy. METHODS: This retrospective case series involved a single cohort longitudinal design of 139 consecutively chosen women who began methadone therapy before 26 completed gestational weeks. Changes in the single daily dose were based on a standard opiate withdrawal scale and determined from early pregnancy until 6 weeks postpartum. RESULTS: As gestation advanced, the methadone dose increased (86%) rather than remained the same (8%) or decreased (7%). This gradual increase in daily dose during pregnancy (mean increase = 24 mg, 95% confidence level = 20-28 mg) was statistically significant (p < .001) regardless of the initial maintenance dose. By the sixth postpartum week, most subjects (85%) took within 10 mg of their dose at delivery (mean change in dose = -4 mg, 95% confidence interval = -6 to -2 mg). CONCLUSIONS: Daily doses of methadone increased until the third trimester, then remained essentially unchanged through the sixth postpartum week.

Vacuum Technology Considerations For Mass Metrology.

Vacuum weighing of mass artifacts eliminates the necessity of air buoyancy correction and its contribution to the measurement uncertainty. Vacuum weighing is also an important process in the experiments currently underway for the redefinition of the SI mass unit, the kilogram. Creating the optimum vacuum environment for mass metrology requires careful design and selection of construction materials, plumbing components, pumping, and pressure gauging technologies. We review the vacuum technology(1) required for mass metrology and suggest procedures and hardware for successful and reproducible operation.

Effects of buprenorphine and hepatitis C on liver enzymes in adolescents and young adults.

OBJECTIVE: The purpose of this study was to explore changes in transaminase values associated with buprenorphine treatment and hepatitis C status among opioid dependent subjects aged 15-21. METHODS: 152 subjects seeking treatment for opioid dependence were randomized to 2-week detoxification with buprenorphine/naloxone (DETOX) or 12 weeks buprenorphine/naloxone (BUP). Liver chemistries including transaminases were obtained baseline and at 4, 8, and 12 weeks. 111 patients had at least one set of transaminases during treatment and were included in analyses of treatment effects. RESULTS: Overall, 8/60 BUP participants vs. 12/51 DETOX participants had at least one elevated ALT value during follow-up (Chi-square n.s.). 5/60 BUP participants vs. 11/51 DETOX participants had at least one elevated AST value (Chi-square = 3.194, p = .048). Twenty-eight out of 152 participants were hepatitis C (HCV) positive at baseline, and 4 seroconverted within 12 weeks, 2 in each group. HCV status was significantly associated with transaminase abnormalities (p = .009 and p = .006 for ALT an AST, respectively). HCV status had a strong effect on transaminase abnormalities among participants assigned to DETOX, but not among those assigned to BUP. CONCLUSIONS: No evidence was found for hepatotoxicity of buprenorphine in this exploratory analysis. HCV was present in a significant minority of participants and was a significant predictor of transaminase elevation. Results suggest that stabilization on buprenorphine may decrease the frequency of transaminase abnormalities associated with HCV in opioid dependent young people. The high rate of seroconversion underscores the importance of effective treatment and prevention.

Case management: ongoing evaluation of patients' needs in an opioid treatment program.

PURPOSE/OBJECTIVE: Case management has been widely used in mental health and substance abuse services. There have been only a few studies that have examined the use of case management in opioid-treatment programs. In a project funded by the Centers of Substance Abuse Treatment, we looked at the use of case managers and specifically at the treatment needs of this unique population. Our case managers, with the aid of research assistants, surveyed the treatment needs of 189 patients entering an opioid-treatment program over a 3-year period. Patients completed the Needs Assessment Instrument at intake, 6 months, and 12 months. PRIMARY PRACTICE SETTING(S): The use of case managers to assess the needs of opioid-dependent patients is applicable to substance abuse treatment setting especially in opioid-treatment programs that provide methadone or buprenorphine maintenance. FINDINGS/CONCLUSIONS: The critical services most requested were vocational, employment, transportation, dental, emotional, and smoking cessation. There were changes over the 12-month follow-up period in the types and priority of services requested. IMPLICATION FOR CASE MANAGEMENT PRACTICE: The Needs Assessment Instrument is a useful tool for case mangers to assess treatment needs of patients and the overall clinic population. Once sufficient patients have been surveyed, the opioid-treatment program can plan needed services for the clinic. Specific social agencies can be contacted to provide key services. Service needs are not static and as patients improve they may need a different mix of services to support their continued abstinence.

A review of the community reinforcement approach in the treatment of opioid dependence.

This article reviews the Community Reinforcement Approach (CRA) in the treatment of opioid dependence. It covers the use of CRA with both methadone maintenance patients and patients withdrawing from opioids. The data reviewed in the use of CRA in combination with methadone maintenance shows improvement in a number of areas. These include the reduction of opioid use, as well as other drugs of abuse, improved legal status, less psychiatric symptoms, and improved vocational and social functioning. CRA coupled with vouchers can assist in retaining patients in treatment long enough to improve opioid detoxification rates from buprenorphine and coupled with naltrexone may sustain abstinence. Further, the use of a standardized computerized format may extend the utility of CRA.

Extended vs short-term buprenorphine-naloxone for treatment of opioid-addicted youth: a randomized trial.

CONTEXT: The usual treatment for opioid-addicted youth is detoxification and counseling. Extended medication-assisted therapy may be more helpful. OBJECTIVE: To evaluate the efficacy of continuing buprenorphine-naloxone for 12 weeks vs detoxification for opioid-addicted youth. DESIGN, SETTING, AND PATIENTS: Clinical trial at 6 community programs from July 2003 to December 2006 including 152 patients aged 15 to 21 years who were randomized to 12 weeks of buprenorphine-naloxone or a 14-day taper (detox). INTERVENTIONS: Patients in the 12-week buprenorphine-naloxone group were prescribed up to 24 mg per day for 9 weeks and then tapered to week 12; patients in the detox group were prescribed up to 14 mg per day and then tapered to day 14. All were offered weekly individual and group counseling. MAIN OUTCOME MEASURE: Opioid-positive urine test result at weeks 4, 8, and 12. RESULTS: The number of patients younger than 18 years was too small to analyze separately, but overall, patients in the detox group had higher proportions of opioid-positive urine test results at weeks 4 and 8 but not at week 12 (chi(2)(2) = 4.93, P = .09). At week 4, 59 detox patients had positive results (61%; 95% confidence interval [CI] = 47%-75%) vs 58 12-week buprenorphine-naloxone patients (26%; 95% CI = 14%-38%). At week 8, 53 detox patients had positive results (54%; 95% CI = 38%-70%) vs 52 12-week buprenorphine-naloxone patients (23%; 95% CI = 11%-35%). At week 12, 53 detox patients had positive results (51%; 95% CI = 35%-67%) vs 49 12-week buprenorphine-naloxone patients (43%; 95% CI = 29%-57%). By week 12, 16 of 78 detox patients (20.5%) remained in treatment vs 52 of 74 12-week buprenorphine-naloxone patients (70%; chi(2)(1) = 32.90, P < .001). During weeks 1 through 12, patients in the 12-week buprenorphine-naloxone group reported less opioid use (chi(2)(1) = 18.45, P < .001), less injecting (chi(2)(1) = 6.00, P = .01), and less nonstudy addiction treatment (chi(2)(1) = 25.82, P < .001). High levels of opioid use occurred in both groups at follow-up. Four of 83 patients who tested negative for hepatitis C at baseline were positive for hepatitis C at week 12. CONCLUSIONS: Continuing treatment with buprenorphine-naloxone improved outcome compared with short-term detoxification. Further research is necessary to assess the efficacy and safety of longer-term treatment with buprenorphine for young individuals with opioid dependence. TRIAL REGISTRATION: clinicaltrials.gov Identifier: NCT00078130.